Sample records for additive layer manufacturing

  1. Determination of residual stresses in objects at their additive manufacturing by layer-by-layer photopolymerization method

    NASA Astrophysics Data System (ADS)

    Bychkov, P. S.; Chentsov, A. V.; Kozintsev, V. M.; Popov, A. L.

    2018-04-01

    A calculation-experimental technique is developed for identification of the shrinkage stresses generated in objects after their additive manufacturing by layer-by-layer photopolymerization. The technique is based on the analysis of shrinkage deformations at bending occurring in a series of samples in the form of plates-stripes with identical sizes, but with different time of polymerization which is predetermined during their production on the 3D printer.

  2. Evaluation of Advanced Polymers for Additive Manufacturing

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rios, Orlando; Carter, William G.; Kutchko, Cindy

    The goal of this Manufacturing Demonstration Facility (MDF) technical collaboration project between Oak Ridge National Laboratory (ORNL) and PPG Industries, Inc. (PPG) was to evaluate the feasibility of using conventional coatings chemistry and technology to build up material layer-by-layer. The PPG-ORNL study successfully demonstrated that polymeric coatings formulations may overcome many limitations of common thermoplastics used in additive manufacturing (AM), allow lightweight nozzle design for material deposition, and increase build rate. The materials effort focused on layer-by-layer deposition of coatings with each layer fusing together. The combination of materials and deposition results in an additively manufactured build that has sufficientmore » mechanical properties to bear the load of additional layers, yet is capable of bonding across the z-layers to improve build direction strength. The formulation properties were tuned to enable a novel, high-throughput deposition method that is highly scalable, compatible with high loading of reinforcing fillers, and inherently low-cost.« less

  3. Preliminary Investigation of Keyhole Phenomena during Single Layer Fabrication in Laser Additive Manufacturing of Stainless Steel

    NASA Astrophysics Data System (ADS)

    Matilainen, Ville-Pekka; Piili, Heidi; Salminen, Antti; Nyrhilä, Olli

    Laser additive manufacturing (LAM) is a fabrication technology that enables production of complex parts from metallic materials with mechanical properties comparable to conventionally manufactured parts. In the LAM process, parts are manufactured by melting metallic powder layer-by-layer with a laser beam. This manufacturing technology is nowadays called powder bed fusion (PBF) according to the ASTM F2792-12a standard. This strategy involves several different independent and dependent thermal cycles, all of which have an influence on the final properties of the manufactured part. The quality of PBF parts depends strongly on the characteristics of each single laser-melted track and each single layer. This study consequently concentrates on investigating the effects of process parameters such as laser power on single track and layer formation and laser-material interaction phenomena occurring during the PBF process. Experimental tests were done with two different machines: a modified research machine based on an EOS EOSINT M-series system and an EOS EOSINT M280 system. The material used was EOS stainless steel 17-4 PH. Process monitoring was done with an active illuminated high speed camera system. After microscopy analysis, it was concluded that a keyhole can form during laser additive manufacturing of stainless steel. It was noted that heat input has an important effect on the likelihood of keyhole formation. The threshold intensity value for keyhole formation of 106 W/cm2 was exceeded in all manufactured single tracks. Laser interaction time was found to have an effect on penetration depth and keyhole formation, since the penetration depth increased with increased laser interaction time. It was also concluded that active illuminated high speed camera systems are suitable for monitoring of the manufacturing process and facilitate process control.

  4. Additive Manufacturing of Shape Memory Alloys

    NASA Astrophysics Data System (ADS)

    Van Humbeeck, Jan

    2018-04-01

    Selective Laser Melting (SLM) is an additive manufacturing production process, also called 3D printing, in which functional, complex parts are produced by selectively melting patterns in consecutive layers of powder with a laser beam. The pattern the laser beam is following is controlled by software that calculates the pattern by slicing a 3D CAD model of the part to be constructed. Apart from SLM, also other additive manufacturing techniques such as EBM (Electron Beam Melting), FDM (Fused Deposition Modelling), WAAM (Wire Arc Additive Manufacturing), LENS (Laser Engineered Net Shaping such as Laser Cladding) and binder jetting allow to construct complete parts layer upon layer. But since more experience of AM of shape memory alloys is collected by SLM, this paper will overview the potentials, limits and problems of producing NiTi parts by SLM.

  5. Additive Manufacturing Infrared Inspection

    NASA Technical Reports Server (NTRS)

    Gaddy, Darrell

    2014-01-01

    Additive manufacturing is a rapid prototyping technology that allows parts to be built in a series of thin layers from plastic, ceramics, and metallics. Metallic additive manufacturing is an emerging form of rapid prototyping that allows complex structures to be built using various metallic powders. Significant time and cost savings have also been observed using the metallic additive manufacturing compared with traditional techniques. Development of the metallic additive manufacturing technology has advanced significantly over the last decade, although many of the techniques to inspect parts made from these processes have not advanced significantly or have limitations. Several external geometry inspection techniques exist such as Coordinate Measurement Machines (CMM), Laser Scanners, Structured Light Scanning Systems, or even traditional calipers and gages. All of the aforementioned techniques are limited to external geometry and contours or must use a contact probe to inspect limited internal dimensions. This presentation will document the development of a process for real-time dimensional inspection technique and digital quality record of the additive manufacturing process using Infrared camera imaging and processing techniques.

  6. Additive manufacturing in production: challenges and opportunities

    NASA Astrophysics Data System (ADS)

    Ahuja, Bhrigu; Karg, Michael; Schmidt, Michael

    2015-03-01

    Additive manufacturing, characterized by its inherent layer by layer fabrication methodology has been coined by many as the latest revolution in the manufacturing industry. Due to its diversification of Materials, processes, system technology and applications, Additive Manufacturing has been synonymized with terminology such as Rapid prototyping, 3D printing, free-form fabrication, Additive Layer Manufacturing, etc. A huge media and public interest in the technology has led to an innovative attempt of exploring the technology for applications beyond the scope of the traditional engineering industry. Nevertheless, it is believed that a critical factor for the long-term success of Additive Manufacturing would be its ability to fulfill the requirements defined by the traditional manufacturing industry. A parallel development in market trends and product requirements has also lead to a wider scope of opportunities for Additive Manufacturing. The presented paper discusses some of the key challenges which are critical to ensure that Additive Manufacturing is truly accepted as a mainstream production technology in the industry. These challenges would highlight on various aspects of production such as product requirements, process management, data management, intellectual property, work flow management, quality assurance, resource planning, etc. In Addition, changing market trends such as product life cycle, mass customization, sustainability, environmental impact and localized production will form the foundation for the follow up discussion on the current limitations and the corresponding research opportunities. A discussion on ongoing research to address these challenges would include topics like process monitoring, design complexity, process standardization, multi-material and hybrid fabrication, new material development, etc.

  7. Additive manufacturing of liquid/gas diffusion layers for low-cost and high-efficiency hydrogen production

    DOE PAGES

    Mo, Jingke; Zhang, Feng -Yuan; Dehoff, Ryan R.; ...

    2016-01-14

    The electron beam melting (EBM) additive manufacturing technology was used to fabricate titanium liquid/gas diffusion media with high-corrosion resistances and well-controllable multifunctional parameters, including two-phase transport and excellent electric/thermal conductivities, has been first demonstrated. Their applications in proton exchange membrane eletrolyzer cells have been explored in-situ in a cell and characterized ex-situ with SEM and XRD. Compared with the conventional woven liquid/gas diffusion layers (LGDLs), much better performance with EBM fabricated LGDLs is obtained due to their significant reduction of ohmic loss. The EBM technology components exhibited several distinguished advantages in fabricating gas diffusion layer: well-controllable pore morphology and structure,more » rapid prototyping, fast manufacturing, highly customizing and economic. In addition, by taking advantage of additive manufacturing, it possible to fabricate complicated three-dimensional designs of virtually any shape from a digital model into one single solid object faster, cheaper and easier, especially for titanium. More importantly, this development will provide LGDLs with control of pore size, pore shape, pore distribution, and therefore porosity and permeability, which will be very valuable to develop modeling and to validate simulations of electrolyzers with optimal and repeatable performance. Further, it will lead to a manufacturing solution to greatly simplify the PEMEC/fuel cell components and to couple the LGDLs with other parts, since they can be easily integrated together with this advanced manufacturing process« less

  8. Additive Layer Manufacturing for Launcher's Applications

    NASA Astrophysics Data System (ADS)

    Vilanova, J.; Romera, P.; Lasagni, F.; Zorrilla, A.; Perinan, A.

    2014-06-01

    In the next years the European space industry has the challenge of maintaining its competitiveness in launch vehicles (LV) production, due to the growth of competition worldwide. It has to assure its position developing new applied technologies. In this field the effort is focussed on the production of short series of customized products, like payloads, flight components or launcher parts. ALM (Additive Layer Manufacturing) could be a powerful tool that offers new competitiveness factors for this industry, comprising a set of emerging technologies that are becoming a competitor to forming, casting and machining as well as being utilised directly as a complementary alternative.Originally used for prototypes and models, now ALM becomes a very useful technology capable to fabricate functional parts for the space industrial sector. Its demands on rapid technologies are different to "earth" industries, and they aren't so easily satisfied because space is a field with different requirements depending on its application: launchers, reusable vehicles, satellites, probes, low gravity researches, manned spacecraft, or even moon and planetary exploration.This paper reports on the ALM potential applications, under ESA requirements, exploring the challenges and possibilities for its use in the launchers market, trying to answer two basic questions: the first one, whether ALM is a mature technology to be ready for its use as flight hardware; and the second one, if it can be used to reduce the product cycle, and consequently, the development, production and operational costs.

  9. Current use and potential of additive manufacturing for optical applications

    NASA Astrophysics Data System (ADS)

    Brunelle, Matthew; Ferralli, Ian; Whitsitt, Rebecca; Medicus, Kate

    2017-10-01

    Additive manufacturing, or 3D printing, has become widely used in recent years for the creation of both prototype and end-use parts. Because the parts are created in a layer-by-layer manner, the flexibility of additive manufacturing is unparalleled and has opened the design space to enable features like undercuts and internal channels which cannot exist on traditional, subtractively manufactured parts. This flexibility can also be leveraged for optical applications. This paper outlines some of the current uses of 3D printing in the optical manufacturing process at Optimax. Several materials and additive technologies are utilized, including polymer printing through fused deposition modeling, which creates parts by depositing a softened thermoplastic filament in a layerwise fashion. Stereolithography, which uses light to cure layers of a photopolymer resin, will also be discussed. These technologies are used to manufacture functional prototypes, fixtures, sealed housings, and other components. Additionally, metal printing through selective laser melting, which uses a laser to melt metal powder layers into a dense solid, will be discussed due to the potential to manufacture thermally stable opticalmechanical assembly frameworks and functional optics. Examples of several additively manufactured optical components will be shown.

  10. Inspection of additive manufactured parts using laser ultrasonics

    NASA Astrophysics Data System (ADS)

    Lévesque, D.; Bescond, C.; Lord, M.; Cao, X.; Wanjara, P.; Monchalin, J.-P.

    2016-02-01

    Additive manufacturing is a novel technology of high importance for global sustainability of resources. As additive manufacturing involves typically layer-by-layer fusion of the feedstock (wire or powder), an important characteristic of the fabricated metallic structural parts, such as those used in aero-engines, is the performance, which is highly related to the presence of defects, such as cracks, lack of fusion or bonding between layers, and porosity. For this purpose, laser ultrasonics is very attractive due to its non-contact nature and is especially suited for the analysis of parts of complex geometries. In addition, the technique is well adapted to online implementation and real-time measurement during the manufacturing process. The inspection can be performed from either the top deposited layer or the underside of the substrate and the defects can be visualized using laser ultrasonics combined with the synthetic aperture focusing technique (SAFT). In this work, a variety of results obtained off-line on INCONEL® 718 and Ti-6Al-4V coupons that were manufactured using laser powder, laser wire, or electron beam wire deposition are reported and most defects detected were further confirmed by X-ray micro-computed tomography.

  11. OPERATOR BURDEN IN METAL ADDITIVE MANUFACTURING

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Elliott, Amy M; Love, Lonnie J

    2016-01-01

    Additive manufacturing (AM) is an emerging manufacturing process that creates usable machine parts via layer-by-layer joining of a stock material. With this layer-wise approach, high-performance geometries can be created which are impossible with traditional manufacturing methods. Metal AM technology has the potential to significantly reduce the manufacturing burden of developing custom hardware; however, a major consideration in choosing a metal AM system is the required amount of operator involvement (i.e., operator burden) in the manufacturing process. The operator burden not only determines the amount of operator training and specialization required but also the usability of the system in a facility.more » As operators of several metal AM processes, the Manufacturing Demonstration Facility (MDF) at Oak Ridge National Labs is uniquely poised to provide insight into requirements for operator involvement in each of the three major metal AM processes. The paper covers an overview of each of the three metal AM technologies, focusing on the burden on the operator to complete the build cycle, process the part for final use, and reset the AM equipment for future builds.« less

  12. Additive manufacturing for steels: a review

    NASA Astrophysics Data System (ADS)

    Zadi-Maad, A.; Rohib, R.; Irawan, A.

    2018-01-01

    Additive manufacturing (AM) of steels involves the layer by layer consolidation of powder or wire feedstock using a heating beam to form near net shape products. For the past decades, the AM technique reaches the maturation of both research grade and commercial production due to significant research work from academic, government and industrial research organization worldwide. AM process has been implemented to replace the conventional process of steel fabrication due to its potentially lower cost and flexibility manufacturing. This paper provides a review of previous research related to the AM methods followed by current challenges issues. The relationship between microstructure, mechanical properties, and process parameters will be discussed. Future trends and recommendation for further works are also provided.

  13. Development and qualification of additively manufactured parts for space

    NASA Astrophysics Data System (ADS)

    O'Brien, Michael J.

    2018-02-01

    Additive manufacturing (commonly called "3D printing") fabricates the desired final part directly from the input CAD (Computer Aided Design) file by depositing and fusing layer upon layer of the source material. New engineering designs are possible in which a single optimized part with novel topology can replace several traditional parts. The complex physics of metal deposition leads to variations in quality and to new flaws and residual stresses not seen in traditional manufacturing. Additive manufacturing currently has gaps in knowledge. Mission assurance will require: qualification and certification standards; sharing of data in handbooks; predictive models relating processing, microstructure and properties; and development of closed loop process control and non-destructive evaluation to reduce variability.

  14. A study on the applications of AI in finishing of additive manufacturing parts

    NASA Astrophysics Data System (ADS)

    Fathima Patham, K.

    2017-06-01

    Artificial intelligent and computer simulation are the technological powerful tools for solving complex problems in the manufacturing industries. Additive Manufacturing is one of the powerful manufacturing techniques that provide design flexibilities to the products. The products with complex shapes are directly manufactured without the need of any machining and tooling using Additive Manufacturing. However, the main drawback of the components produced using the Additive Manufacturing processes is the quality of the surfaces. This study aims to minimize the defects caused during Additive Manufacturing with the aid of Artificial Intelligence. The developed AI system has three layers, each layer is trying to eliminate or minimize the production errors. The first layer of the AI system optimizes the digitization of the 3D CAD model of the product and hence reduces the stair case errors. The second layer of the AI system optimizes the 3D printing machine parameters in order to eliminate the warping effect. The third layer of AI system helps to choose the surface finishing technique suitable for the printed component based on the Degree of Complexity of the product and the material. The efficiency of the developed AI system was examined on the functional parts such as gears.

  15. Surface texture measurement for additive manufacturing

    NASA Astrophysics Data System (ADS)

    Triantaphyllou, Andrew; Giusca, Claudiu L.; Macaulay, Gavin D.; Roerig, Felix; Hoebel, Matthias; Leach, Richard K.; Tomita, Ben; Milne, Katherine A.

    2015-06-01

    The surface texture of additively manufactured metallic surfaces made by powder bed methods is affected by a number of factors, including the powder’s particle size distribution, the effect of the heat source, the thickness of the printed layers, the angle of the surface relative to the horizontal build bed and the effect of any post processing/finishing. The aim of the research reported here is to understand the way these surfaces should be measured in order to characterise them. In published research to date, the surface texture is generally reported as an Ra value, measured across the lay. The appropriateness of this method for such surfaces is investigated here. A preliminary investigation was carried out on two additive manufacturing processes—selective laser melting (SLM) and electron beam melting (EBM)—focusing on the effect of build angle and post processing. The surfaces were measured using both tactile and optical methods and a range of profile and areal parameters were reported. Test coupons were manufactured at four angles relative to the horizontal plane of the powder bed using both SLM and EBM. The effect of lay—caused by the layered nature of the manufacturing process—was investigated, as was the required sample area for optical measurements. The surfaces were also measured before and after grit blasting.

  16. A case study on topology optimized design for additive manufacturing

    NASA Astrophysics Data System (ADS)

    Gebisa, A. W.; Lemu, H. G.

    2017-12-01

    Topology optimization is an optimization method that employs mathematical tools to optimize material distribution in a part to be designed. Earlier developments of topology optimization considered conventional manufacturing techniques that have limitations in producing complex geometries. This has hindered the topology optimization efforts not to fully be realized. With the emergence of additive manufacturing (AM) technologies, the technology that builds a part layer upon a layer directly from three dimensional (3D) model data of the part, however, producing complex shape geometry is no longer an issue. Realization of topology optimization through AM provides full design freedom for the design engineers. The article focuses on topologically optimized design approach for additive manufacturing with a case study on lightweight design of jet engine bracket. The study result shows that topology optimization is a powerful design technique to reduce the weight of a product while maintaining the design requirements if additive manufacturing is considered.

  17. Additive manufacturing.

    PubMed

    Mumith, A; Thomas, M; Shah, Z; Coathup, M; Blunn, G

    2018-04-01

    Increasing innovation in rapid prototyping (RP) and additive manufacturing (AM), also known as 3D printing, is bringing about major changes in translational surgical research. This review describes the current position in the use of additive manufacturing in orthopaedic surgery. Cite this article: Bone Joint J 2018;100-B:455-60.

  18. Utilization of curve offsets in additive manufacturing

    NASA Astrophysics Data System (ADS)

    Haseltalab, Vahid; Yaman, Ulas; Dolen, Melik

    2018-05-01

    Curve offsets are utilized in different fields of engineering and science. Additive manufacturing, which lately becomes an explicit requirement in manufacturing industry, utilizes curve offsets widely. One of the necessities of offsetting is for scaling which is required if there is shrinkage after the fabrication or if the surface quality of the resulting part is unacceptable. Therefore, some post-processing is indispensable. But the major application of curve offsets in additive manufacturing processes is for generating head trajectories. In a point-wise AM process, a correct tool-path in each layer can reduce lots of costs and increase the surface quality of the fabricated parts. In this study, different curve offset generation algorithms are analyzed to show their capabilities and disadvantages through some test cases and improvements on their drawbacks are suggested.

  19. Emerging technologies in arthroplasty: additive manufacturing.

    PubMed

    Banerjee, Samik; Kulesha, Gene; Kester, Mark; Mont, Michael A

    2014-06-01

    Additive manufacturing is an industrial technology whereby three-dimensional visual computer models are fabricated into physical components by selectively curing, depositing, or consolidating various materials in consecutive layers. Although initially developed for production of simulated models, the technology has undergone vast improvements and is currently increasingly being used for the production of end-use components in various aerospace, automotive, and biomedical specialties. The ability of this technology to be used for the manufacture of solid-mesh-foam monolithic and coated components of complex geometries previously considered unmanufacturable has attracted the attention of implant manufacturers, bioengineers, and orthopedic surgeons. Currently, there is a paucity of reports describing this fabrication method in the orthopedic literature. Therefore, we aimed to briefly describe this technology, some of the applications in other orthopedic subspecialties, its present use in hip and knee arthroplasty, and concerns with the present form of the technology. As there are few reports of clinical trials presently available, the true benefits of this technology can only be realized when studies evaluating the clinical and radiographic outcomes of cementless implants manufactured with additive manufacturing report durable fixation, less stress shielding, and better implant survivorship. Nevertheless, the authors believe that this technology holds great promise and may potentially change the conventional methods of casting, machining, and tooling for implant manufacturing in the future. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  20. Fully additive manufacture of a polymer cantilever with an embedded functional layer

    NASA Astrophysics Data System (ADS)

    Kanazawa, Shusuke; Kusaka, Yasuyuki; Horii, Yoshinori; Ushijima, Hirobumi

    2018-03-01

    In this paper, we report on an efficient and unique printing-based process for fabricating a cantilever structure with an embedded functional layer. The process is used to form a micro suspended structure via the one-batch transfer of stacked layers from a dummy substrate. The mechanism of the transfer process is clearly explained by the order of adhesion strengths of all interfaces. As a demonstration, a strain gauge which consisted of a polymer cantilever with an embedded conductive wire was successfully fabricated. It is expected that the proposed process will widely contribute to the efficient manufacture of useful sensors and actuators.

  1. Surface-specific additive manufacturing test artefacts

    NASA Astrophysics Data System (ADS)

    Townsend, Andrew; Racasan, Radu; Blunt, Liam

    2018-06-01

    Many test artefact designs have been proposed for use with additive manufacturing (AM) systems. These test artefacts have primarily been designed for the evaluation of AM form and dimensional performance. A series of surface-specific measurement test artefacts designed for use in the verification of AM manufacturing processes are proposed here. Surface-specific test artefacts can be made more compact because they do not require the large dimensions needed for accurate dimensional and form measurements. The series of three test artefacts are designed to provide comprehensive information pertaining to the manufactured surface. Measurement possibilities include deviation analysis, surface texture parameter data generation, sub-surface analysis, layer step analysis and build resolution comparison. The test artefacts are designed to provide easy access for measurement using conventional surface measurement techniques, for example, focus variation microscopy, stylus profilometry, confocal microscopy and scanning electron microscopy. Additionally, the test artefacts may be simply visually inspected as a comparative tool, giving a fast indication of process variation between builds. The three test artefacts are small enough to be included in every build and include built-in manufacturing traceability information, making them a convenient physical record of the build.

  2. An In-Depth Review on Direct Additive Manufacturing of Metals

    NASA Astrophysics Data System (ADS)

    Azam, Farooq I.; Rani, Ahmad Majdi Abdul; Altaf, Khurram; Rao, T. V. V. L. N.; Aimi Zaharin, Haizum

    2018-03-01

    Additive manufacturing (AM), also known as 3D Printing, is a revolutionary manufacturing technique which has been developing rapidly in the last 30 years. The evolution of this precision manufacturing process from rapid prototyping to ready-to-use parts has significantly alleviated manufacturing constraints and design freedom has been outstandingly widened. AM is a non-conventional manufacturing technique which utilizes a 3D CAD model data to build parts by adding one material layer at a time, rather than removing it and fulfills the demand for manufacturing parts with complex geometric shapes, great dimensional accuracy, and easy to assemble parts. Additive manufacturing of metals has become the area of extensive research, progressing towards the production of final products and replacing conventional manufacturing methods. This paper provides an insight to the available metal additive manufacturing technologies that can be used to produce end user products without using conventional manufacturing methods. The paper also includes the comparison of mechanical and physical properties of parts produced by AM with the parts manufactured using conventional processes.

  3. Additive manufacturing: From implants to organs.

    PubMed

    Douglas, Tania S

    2014-05-12

    Additive manufacturing (AM) constructs 3D objects layer by layer under computer control from 3D models. 3D printing is one example of this kind of technology. AM offers geometric flexibility in its products and therefore allows customisation to suit individual needs. Clinical success has been shown with models for surgical planning, implants, assistive devices and scaffold-based tissue engineering. The use of AM to print tissues and organs that mimic nature in structure and function remains an elusive goal, but has the potential to transform personalised medicine, drug development and scientific understanding of the mechanisms of disease. 

  4. Additive Manufacturing Infrared Inspection

    NASA Technical Reports Server (NTRS)

    Gaddy, Darrell; Nettles, Mindy

    2015-01-01

    The Additive Manufacturing Infrared Inspection Task started the development of a real-time dimensional inspection technique and digital quality record for the additive manufacturing process using infrared camera imaging and processing techniques. This project will benefit additive manufacturing by providing real-time inspection of internal geometry that is not currently possible and reduce the time and cost of additive manufactured parts with automated real-time dimensional inspections which deletes post-production inspections.

  5. Computational Process Modeling for Additive Manufacturing (OSU)

    NASA Technical Reports Server (NTRS)

    Bagg, Stacey; Zhang, Wei

    2015-01-01

    Powder-Bed Additive Manufacturing (AM) through Direct Metal Laser Sintering (DMLS) or Selective Laser Melting (SLM) is being used by NASA and the Aerospace industry to "print" parts that traditionally are very complex, high cost, or long schedule lead items. The process spreads a thin layer of metal powder over a build platform, then melts the powder in a series of welds in a desired shape. The next layer of powder is applied, and the process is repeated until layer-by-layer, a very complex part can be built. This reduces cost and schedule by eliminating very complex tooling and processes traditionally used in aerospace component manufacturing. To use the process to print end-use items, NASA seeks to understand SLM material well enough to develop a method of qualifying parts for space flight operation. Traditionally, a new material process takes many years and high investment to generate statistical databases and experiential knowledge, but computational modeling can truncate the schedule and cost -many experiments can be run quickly in a model, which would take years and a high material cost to run empirically. This project seeks to optimize material build parameters with reduced time and cost through modeling.

  6. Operational Cybersecurity Risks and Their Effect on Adoption of Additive Manufacturing in the Naval Domain

    DTIC Science & Technology

    2017-12-01

    material and limiting overproduction issues experienced in traditional manufacturing . Figure 2 shows how AM may also speed productivity by reducing time...schematic from a file and have a computer printer create that item in real life layer by layer 30. Geek method of manufacture at low rate of production and...a three dimensional form. 46. Additive production technique utilizing material extruded onto a bed, usually in 3-axes. 47. Additive manufacturing

  7. Designing an in-situ ultrasonic nondestructive evaluation system for ultrasonic additive manufacturing

    NASA Astrophysics Data System (ADS)

    Nadimpalli, Venkata K.; Nagy, Peter B.

    2018-04-01

    Ultrasonic Additive Manufacturing (UAM) is a solid-state layer by layer manufacturing process that utilizes vibration induced plastic deformation to form a metallurgical bond between a thin layer and an existing base structure. Due to the vibration based bonding mechanism, the quality of components at each layer depends on the geometry of the structure. In-situ monitoring during and between UAM manufacturing steps offers the potential for closed-loop control to optimize process parameters and to repair existing defects. One interface that is most prone to delamination is the base/build interface and often UAM component height and quality are limited by failure at the base/build interface. Low manufacturing temperatures and favorable orientation of typical interface defects in UAM make ultrasonic NDE an attractive candidate for online monitoring. Two approaches for in-situ NDE are discussed and the design of the monitoring system optimized so that the quality of UAM components is not affected by the addition of the NDE setup. Preliminary results from in-situ ultrasonic NDE indicate the potential to be utilized for online qualification, closed-loop control and offline certification of UAM components.

  8. Build platform that provides mechanical engagement with additive manufacturing prints

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Elliott, Amelia M.

    A build platform and methods of fabricating an article with such a platform in an extrusion-type additive manufacturing machine are provided. A platform body 202 includes features 204 that extend outward from the body 202. The features 204 define protrusive areas 206 and recessive areas 208 that cooperate to mechanically engage the extruded material that forms the initial layers 220 of an article when the article is being fabricated by a nozzle 12 of the additive manufacturing machine 10.

  9. Design and development of a layer-based additive manufacturing process for the realization of metal parts of designed mesostructure

    NASA Astrophysics Data System (ADS)

    Williams, Christopher Bryant

    Low-density cellular materials, metallic bodies with gaseous voids, are a unique class of materials that are characterized by their high strength, low mass, good energy absorption characteristics, and good thermal and acoustic insulation properties. In an effort to take advantage of this entire suite of positive mechanical traits, designers are tailoring the cellular mesostructure for multiple design objectives. Unfortunately, existing cellular material manufacturing technologies limit the design space as they are limited to certain part mesostructure, material type, and macrostructure. The opportunity that exists to improve the design of existing products, and the ability to reap the benefits of cellular materials in new applications is the driving force behind this research. As such, the primary research goal of this work is to design, embody, and analyze a manufacturing process that provides a designer the ability to specify the material type, material composition, void morphology, and mesostructure topology for any conceivable part geometry. The accomplishment of this goal is achieved in three phases of research: (1) Design---Following a systematic design process and a rigorous selection exercise, a layer-based additive manufacturing process is designed that is capable of meeting the unique requirements of fabricating cellular material geometry. Specifically, metal parts of designed mesostructure are fabricated via three-dimensional printing of metal oxide ceramic powder followed by post-processing in a reducing atmosphere. (2) Embodiment ---The primary research hypothesis is verified through the use of the designed manufacturing process chain to successfully realize metal parts of designed mesostructure. (3) Modeling & Evaluation ---The designed manufacturing process is modeled in this final research phase so as to increase understanding of experimental results and to establish a foundation for future analytical modeling research. In addition to an analysis of

  10. Additive Manufacturing of PLA and CF/PLA Binding Layer Specimens via Fused Deposition Modeling

    NASA Astrophysics Data System (ADS)

    Li, Yuhang; Gao, Shiyou; Dong, Rongmei; Ding, Xuebing; Duan, Xiaoxi

    2018-02-01

    As one of the most popular additive manufacturing techniques, fused deposition modeling (FDM) is successfully applied in aerospace, automotive, architecture, and other fields to fabricate thermoplastic parts. Unfortunately, as a result of the limited nature of the mechanical properties and mass in raw materials, there is a pressing need to improve mechanical properties and reduce weight for FDM parts. Therefore, this paper presents an experiment of a special polylactic acid (PLA) and carbon fiber (CF)/PLA-laminated experimental specimen fabricated using the FDM process. The mechanical properties and mass analysis of the new composites for the PLA and CF/PLA binding layer specimen are investigated experimentally. Through the experimental analysis, one can conclude that the mass of laminated specimen is lighter than the CF/PLA specimen, and the tensile and flexural mechanical properties are higher than the pure PLA specimen.

  11. Five-Axis Ultrasonic Additive Manufacturing for Nuclear Component Manufacture

    NASA Astrophysics Data System (ADS)

    Hehr, Adam; Wenning, Justin; Terrani, Kurt; Babu, Sudarsanam Suresh; Norfolk, Mark

    2017-03-01

    Ultrasonic additive manufacturing (UAM) is a three-dimensional metal printing technology which uses high-frequency vibrations to scrub and weld together both similar and dissimilar metal foils. There is no melting in the process and no special atmosphere requirements are needed. Consequently, dissimilar metals can be joined with little to no intermetallic compound formation, and large components can be manufactured. These attributes have the potential to transform manufacturing of nuclear reactor core components such as control elements for the High Flux Isotope Reactor at Oak Ridge National Laboratory. These components are hybrid structures consisting of an outer cladding layer in contact with the coolant with neutron-absorbing materials inside, such as neutron poisons for reactor control purposes. UAM systems are built into a computer numerical control (CNC) framework to utilize intermittent subtractive processes. These subtractive processes are used to introduce internal features as the component is being built and for net shaping. The CNC framework is also used for controlling the motion of the welding operation. It is demonstrated here that curved components with embedded features can be produced using a five-axis code for the welder for the first time.

  12. Five-axis ultrasonic additive manufacturing for nuclear component manufacture

    DOE PAGES

    Hehr, Adam; Wenning, Justin; Terrani, Kurt A.; ...

    2016-01-01

    Ultrasonic additive manufacturing (UAM) is a three-dimensional metal printing technology which uses high-frequency vibrations to scrub and weld together both similar and dissimilar metal foils. There is no melting in the process and no special atmosphere requirements are needed. Consequently, dissimilar metals can be joined with little to no intermetallic compound formation, and large components can be manufactured. These attributes have the potential to transform manufacturing of nuclear reactor core components such as control elements for the High Flux Isotope Reactor at Oak Ridge National Laboratory. These components are hybrid structures consisting of an outer cladding layer in contact withmore » the coolant with neutron-absorbing materials inside, such as neutron poisons for reactor control purposes. UAM systems are built into a computer numerical control (CNC) framework to utilize intermittent subtractive processes. These subtractive processes are used to introduce internal features as the component is being built and for net shaping. The CNC framework is also used for controlling the motion of the welding operation. Lastly, it is demonstrated here that curved components with embedded features can be produced using a five-axis code for the welder for the first time.« less

  13. Additive manufacturing of glass for optical applications

    NASA Astrophysics Data System (ADS)

    Luo, Junjie; Gilbert, Luke J.; Bristow, Douglas A.; Landers, Robert G.; Goldstein, Jonathan T.; Urbas, Augustine M.; Kinzel, Edward C.

    2016-04-01

    Glasses including fused quartz have significant scientific and engineering applications including optics, communications, electronics, and hermetic seals. This paper investigates a filament fed process for Additive Manufacturing (AM) of fused quartz. Additive manufacturing has several potential benefits including increased design freedom, faster prototyping, and lower processing costs for small production volumes. However, current research in AM of glasses is limited and has focused on non-optical applications. Fused quartz is studied here because of its desirability for high-quality optics due to its high transmissivity and thermal stability. Fused quartz also has a higher working temperature than soda lime glass which poses a challenge for AM. In this work, fused quartz filaments are fed into a CO2 laser generated melt pool, smoothly depositing material onto the work piece. Single tracks are printed to explore the effects that different process parameters have on the morphology of printed fused quartz. A spectrometer is used to measure the thermal radiation incandescently emitted from the melt pool. Thin-walls are printed to study the effects of layer-to-layer height. Finally, a 3D fused quartz cube is printed using the newly acquired layer height and polished on each surface. The transmittance and index homogeneity of the polished cube are both measured. These results show that the filament fed process has the potential to print fused quartz with optical transparency and of index of refraction uniformity approaching bulk processed glass.

  14. Additive manufacturing of optical components

    NASA Astrophysics Data System (ADS)

    Heinrich, Andreas; Rank, Manuel; Maillard, Philippe; Suckow, Anne; Bauckhage, Yannick; Rößler, Patrick; Lang, Johannes; Shariff, Fatin; Pekrul, Sven

    2016-08-01

    The development of additive manufacturing methods has enlarged rapidly in recent years. Thereby, the work mainly focuses on the realization of mechanical components, but the additive manufacturing technology offers a high potential in the field of optics as well. Owing to new design possibilities, completely new solutions are possible. This article briefly reviews and compares the most important additive manufacturing methods for polymer optics. Additionally, it points out the characteristics of additive manufactured polymer optics. Thereby, surface quality is of crucial importance. In order to improve it, appropriate post-processing steps are necessary (e.g. robot polishing or coating), which will be discussed. An essential part of this paper deals with various additive manufactured optical components and their use, especially in optical systems for shape metrology (e.g. borehole sensor, tilt sensor, freeform surface sensor, fisheye lens). The examples should demonstrate the potentials and limitations of optical components produced by additive manufacturing.

  15. Mechanical properties of sheet metal components with local reinforcement produced by additive manufacturing

    NASA Astrophysics Data System (ADS)

    Ünsal, Ismail; Hama-Saleh, R.; Sviridov, Alexander; Bambach, Markus; Weisheit, A.; Schleifenbaum, J. H.

    2018-05-01

    New technological challenges like electro-mobility pose an increasing demand for cost-efficient processes for the production of product variants. This demand opens the possibility to combine established die-based manufacturing methods and innovative, dieless technologies like additive manufacturing [1, 2]. In this context, additive manufacturing technologies allow for the weight-efficient local reinforcement of parts before and after forming, enabling manufacturers to produce product variants from series parts [3]. Previous work by the authors shows that the optimal shape of the reinforcing structure can be determined using sizing optimization. Sheet metal parts can then be reinforced using laser metal deposition. The material used is a pearlite-reduced, micro-alloyed steel (ZE 630). The aim of this paper is to determine the effect of the additive manufacturing process on the material behavior and the mechanical properties of the base material and the resulting composite material. The parameters of the AM process are optimized to reach similar material properties in the base material and the build-up volume. A metallographic analysis of the parts is presented, where the additive layers, the base material and also the bonding between the additive layers and the base material are analyzed. The paper shows the feasibility of the approach and details the resulting mechanical properties and performance.

  16. Structural optimization under overhang constraints imposed by additive manufacturing technologies

    NASA Astrophysics Data System (ADS)

    Allaire, G.; Dapogny, C.; Estevez, R.; Faure, A.; Michailidis, G.

    2017-12-01

    This article addresses one of the major constraints imposed by additive manufacturing processes on shape optimization problems - that of overhangs, i.e. large regions hanging over void without sufficient support from the lower structure. After revisiting the 'classical' geometric criteria used in the literature, based on the angle between the structural boundary and the build direction, we propose a new mechanical constraint functional, which mimics the layer by layer construction process featured by additive manufacturing technologies, and thereby appeals to the physical origin of the difficulties caused by overhangs. This constraint, as well as some variants, is precisely defined; their shape derivatives are computed in the sense of Hadamard's method, and numerical strategies are extensively discussed, in two and three space dimensions, to efficiently deal with the appearance of overhang features in the course of shape optimization processes.

  17. Neutron Characterization for Additive Manufacturing

    NASA Technical Reports Server (NTRS)

    Watkins, Thomas; Bilheux, Hassina; An, Ke; Payzant, Andrew; DeHoff, Ryan; Duty, Chad; Peter, William; Blue, Craig; Brice, Craig A.

    2013-01-01

    Oak Ridge National Laboratory (ORNL) is leveraging decades of experience in neutron characterization of advanced materials together with resources such as the Spallation Neutron Source (SNS) and the High Flux Isotope Reactor (HFIR) shown in Fig. 1 to solve challenging problems in additive manufacturing (AM). Additive manufacturing, or three-dimensional (3-D) printing, is a rapidly maturing technology wherein components are built by selectively adding feedstock material at locations specified by a computer model. The majority of these technologies use thermally driven phase change mechanisms to convert the feedstock into functioning material. As the molten material cools and solidifies, the component is subjected to significant thermal gradients, generating significant internal stresses throughout the part (Fig. 2). As layers are added, inherent residual stresses cause warping and distortions that lead to geometrical differences between the final part and the original computer generated design. This effect also limits geometries that can be fabricated using AM, such as thin-walled, high-aspect- ratio, and overhanging structures. Distortion may be minimized by intelligent toolpath planning or strategic placement of support structures, but these approaches are not well understood and often "Edisonian" in nature. Residual stresses can also impact component performance during operation. For example, in a thermally cycled environment such as a high-pressure turbine engine, residual stresses can cause components to distort unpredictably. Different thermal treatments on as-fabricated AM components have been used to minimize residual stress, but components still retain a nonhomogeneous stress state and/or demonstrate a relaxation-derived geometric distortion. Industry, federal laboratory, and university collaboration is needed to address these challenges and enable the U.S. to compete in the global market. Work is currently being conducted on AM technologies at the ORNL

  18. The metallurgy and processing science of metal additive manufacturing

    DOE PAGES

    Sames, William J.; List, III, Frederick Alyious; Pannala, Sreekanth; ...

    2016-03-07

    Here, additive Manufacturing (AM), widely known as 3D printing, is a method of manufacturing that forms parts from powder, wire, or sheets in a process that proceeds layer-by-layer.Many techniques (using many different names) have been developed to accomplish this via melting or solid - state joining. In this review, these techniques for producing metal parts are explored, with a focus on the science of metal AM: processing defects, heat transfer, solidification, solid- state precipitation, mechanical properties, and post-processing metallurgy. The various metal AM techniques are compared, with analysis of the strengths and limitations of each. Few alloys have been developedmore » for commercial production, but recent development efforts are presented as a path for the ongoing development of new materials for AM processes.« less

  19. Additive Manufacturing of Silicon Carbide-Based Ceramic Matrix Composites: Technical Challenges and Opportunities

    NASA Technical Reports Server (NTRS)

    Singh, Mrityunjay; Halbig, Michael C.; Grady, Joseph E.

    2016-01-01

    Advanced SiC-based ceramic matrix composites offer significant contributions toward reducing fuel burn and emissions by enabling high overall pressure ratio (OPR) of gas turbine engines and reducing or eliminating cooling air in the hot-section components, such as shrouds, combustor liners, vanes, and blades. Additive manufacturing (AM), which allows high value, custom designed parts layer by layer, has been demonstrated for metals and polymer matrix composites. However, there has been limited activity on additive manufacturing of ceramic matrix composites (CMCs). In this presentation, laminated object manufacturing (LOM), binder jet process, and 3-D printing approaches for developing ceramic composite materials are presented. For the laminated object manufacturing (LOM), fiber prepreg laminates were cut into shape with a laser and stacked to form the desired part followed by high temperature heat treatments. For the binder jet, processing optimization was pursued through silicon carbide powder blending, infiltration with and without SiC nano powder loading, and integration of fibers into the powder bed. Scanning electron microscopy was conducted along with XRD, TGA, and mechanical testing. Various technical challenges and opportunities for additive manufacturing of ceramics and CMCs will be presented.

  20. Monitoring system for the quality assessment in additive manufacturing

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Carl, Volker, E-mail: carl@t-zfp.de

    Additive Manufacturing (AM) refers to a process by which a set of digital data -representing a certain complex 3dim design - is used to grow the respective 3dim real structure equal to the corresponding design. For the powder-based EOS manufacturing process a variety of plastic and metal materials can be used. Thereby, AM is in many aspects a very powerful tool as it can help to overcome particular limitations in conventional manufacturing. AM enables more freedom of design, complex, hollow and/or lightweight structures as well as product individualisation and functional integration. As such it is a promising approach with respectmore » to the future design and manufacturing of complex 3dim structures. On the other hand, it certainly calls for new methods and standards in view of quality assessment. In particular, when utilizing AM for the design of complex parts used in aviation and aerospace technologies, appropriate monitoring systems are mandatory. In this respect, recently, sustainable progress has been accomplished by joining the common efforts and concerns of a manufacturer Additive Manufacturing systems and respective materials (EOS), along with those of an operator of such systems (MTU Aero Engines) and experienced application engineers (Carl Metrology), using decent know how in the field of optical and infrared methods regarding non-destructive-examination (NDE). The newly developed technology is best described by a high-resolution layer by layer inspection technique, which allows for a 3D tomography-analysis of the complex part at any time during the manufacturing process. Thereby, inspection costs are kept rather low by using smart image-processing methods as well as CMOS sensors instead of infrared detectors. Moreover, results from conventional physical metallurgy may easily be correlated with the predictive results of the monitoring system which not only allows for improvements of the AM monitoring system, but finally leads to an optimisation of the

  1. Monitoring system for the quality assessment in additive manufacturing

    NASA Astrophysics Data System (ADS)

    Carl, Volker

    2015-03-01

    Additive Manufacturing (AM) refers to a process by which a set of digital data -representing a certain complex 3dim design - is used to grow the respective 3dim real structure equal to the corresponding design. For the powder-based EOS manufacturing process a variety of plastic and metal materials can be used. Thereby, AM is in many aspects a very powerful tool as it can help to overcome particular limitations in conventional manufacturing. AM enables more freedom of design, complex, hollow and/or lightweight structures as well as product individualisation and functional integration. As such it is a promising approach with respect to the future design and manufacturing of complex 3dim structures. On the other hand, it certainly calls for new methods and standards in view of quality assessment. In particular, when utilizing AM for the design of complex parts used in aviation and aerospace technologies, appropriate monitoring systems are mandatory. In this respect, recently, sustainable progress has been accomplished by joining the common efforts and concerns of a manufacturer Additive Manufacturing systems and respective materials (EOS), along with those of an operator of such systems (MTU Aero Engines) and experienced application engineers (Carl Metrology), using decent know how in the field of optical and infrared methods regarding non-destructive-examination (NDE). The newly developed technology is best described by a high-resolution layer by layer inspection technique, which allows for a 3D tomography-analysis of the complex part at any time during the manufacturing process. Thereby, inspection costs are kept rather low by using smart image-processing methods as well as CMOS sensors instead of infrared detectors. Moreover, results from conventional physical metallurgy may easily be correlated with the predictive results of the monitoring system which not only allows for improvements of the AM monitoring system, but finally leads to an optimisation of the quality

  2. Weld formation during material extrusion additive manufacturing.

    PubMed

    Seppala, Jonathan E; Hoon Han, Seung; Hillgartner, Kaitlyn E; Davis, Chelsea S; Migler, Kalman B

    2017-10-04

    Material extrusion (ME) is a layer-by-layer additive manufacturing process that is now used in personal and commercial production where prototyping and customization are required. However, parts produced from ME frequently exhibit poor mechanical performance relative to those from traditional means; moreover, fundamental knowledge of the factors leading to development of inter-layer strength in this highly non-isothermal process is limited. In this work, we seek to understand the development of inter-layer weld strength from the perspective of polymer interdiffusion under conditions of rapidly changing mobility. Our framework centers around three interrelated components: in situ thermal measurements (via infrared imaging), temperature dependent molecular processes (via rheology), and mechanical testing (via mode III fracture). We develop the concept of an equivalent isothermal weld time and test its relationship to fracture energy. For the printing conditions studied the equivalent isothermal weld time for T ref = 230 °C ranged from 0.1 ms to 100 ms. The results of these analysis provide a basis for optimizing inter-layer strength, the limitations of the ME process, and guide development of new materials.

  3. Development of an arthroscopically compatible polymer additive layer manufacture technique.

    PubMed

    Partridge, Simon W; Benning, Matthew J; German, Matthew J; Dalgarno, Kenneth W

    2017-06-01

    This article describes a proof of concept study designed to evaluate the potential of an in vivo three-dimensional printing route to support minimally invasive repair of the musculoskeletal system. The study uses a photocurable material to additively manufacture in situ a model implant and demonstrates that this can be achieved effectively within a clinically relevant timescale. The approach has the potential to be applied with a wide range of light-curable materials and with development could be applied to create functionally gradient structures in vivo.

  4. Additive Manufactured Product Integrity

    NASA Technical Reports Server (NTRS)

    Waller, Jess; Wells, Doug; James, Steve; Nichols, Charles

    2017-01-01

    NASA is providing key leadership in an international effort linking NASA and non-NASA resources to speed adoption of additive manufacturing (AM) to meet NASA's mission goals. Participants include industry, NASA's space partners, other government agencies, standards organizations and academia. Nondestructive Evaluation (NDE) is identified as a universal need for all aspects of additive manufacturing.

  5. 3D Printing, Additive Manufacturing, and Solid Freeform Fabrication: The Technologies of the Past, Present and Future

    NASA Astrophysics Data System (ADS)

    Beaman, Joseph

    2015-03-01

    Starting in the late 1980's, several new technologies were created that have the potential to revolutionize manufacturing. These technologies are, for the most part, additive processes that build up parts layer by layer. In addition, the processes that are being touted for hard-core manufacturing are primarily laser or e-beam based processes. This presentation gives a brief history of Additive Manufacturing and gives an assessment for these technologies. These technologies initially grew out of a commercial need for rapid prototyping. This market has a different requirement for process and quality control than traditional manufacturing. The relatively poor process control of the existing commercial Additive Manufacturing equipment is a vestige of this history. This presentation discusses this history and improvements in quality over time. The emphasis will be on Additive Manufacturing processes that are being considered for direct manufacturing, which is a different market than the 3D Printing ``Makerbot'' market. Topics discussed include past and present machine sensors, materials, and operational methods that were used in the past and those that are used today to create manufactured parts. Finally, a discussion of new methods and future directions of AM is presented.

  6. A new application for food customization with additive manufacturing technologies

    NASA Astrophysics Data System (ADS)

    Serenó, L.; Vallicrosa, G.; Delgado, J.; Ciurana, J.

    2012-04-01

    Additive Manufacturing (AM) technologies have emerged as a freeform approach capable of producing almost any complete three dimensional (3D) objects from computer-aided design (CAD) data by successively adding material layer by layer. Despite the broad range of possibilities, commercial AM technologies remain complex and expensive, making them suitable only for niche applications. The developments of the Fab@Home system as an open AM technology discovered a new range of possibilities of processing different materials such as edible products. The main objective of this work is to analyze and optimize the manufacturing capacity of this system when producing 3D edible objects. A new heated syringe deposition tool was developed and several process parameters were optimized to adapt this technology to consumers' needs. The results revealed in this study show the potential of this system to produce customized edible objects without qualified personnel knowledge, therefore saving manufacturing costs compared to traditional technologies.

  7. Terahertz imaging and tomography as efficient instruments for testing polymer additive manufacturing objects.

    PubMed

    Perraud, J B; Obaton, A F; Bou-Sleiman, J; Recur, B; Balacey, H; Darracq, F; Guillet, J P; Mounaix, P

    2016-05-01

    Additive manufacturing (AM) technology is not only used to make 3D objects but also for rapid prototyping. In industry and laboratories, quality controls for these objects are necessary though difficult to implement compared to classical methods of fabrication because the layer-by-layer printing allows for very complex object manufacturing that is unachievable with standard tools. Furthermore, AM can induce unknown or unexpected defects. Consequently, we demonstrate terahertz (THz) imaging as an innovative method for 2D inspection of polymer materials. Moreover, THz tomography may be considered as an alternative to x-ray tomography and cheaper 3D imaging for routine control. This paper proposes an experimental study of 3D polymer objects obtained by additive manufacturing techniques. This approach allows us to characterize defects and to control dimensions by volumetric measurements on 3D data reconstructed by tomography.

  8. Increasing component functionality via multi-process additive manufacturing

    NASA Astrophysics Data System (ADS)

    Coronel, Jose L.; Fehr, Katherine H.; Kelly, Dominic D.; Espalin, David; Wicker, Ryan B.

    2017-05-01

    Additively manufactured components, although extensively customizable, are often limited in functionality. Multi-process additive manufacturing (AM) grants the ability to increase the functionality of components via subtractive manufacturing, wire embedding, foil embedding and pick and place. These processes are scalable to include several platforms ranging from desktop to large area printers. The Multi3D System is highlighted, possessing the capability to perform the above mentioned processes, all while transferring a fabricated component with a robotic arm. Work was conducted to fabricate a patent inspired, printed missile seeker. The seeker demonstrated the advantage of multi-process AM via introduction of the pick and place process. Wire embedding was also explored, with the successful interconnect of two layers of embedded wires in different planes. A final demonstration of a printed contour bracket, served to show the reduction of surface roughness on a printed part is 87.5% when subtractive manufacturing is implemented in tandem with AM. Functionality of the components on all the cases was improved. Results included optical components embedded within the printed housing, wires embedded with interconnection, and reduced surface roughness. These results highlight the improved functionality of components through multi-process AM, specifically through work conducted with the Multi3D System.

  9. Additive manufacturing with polypropylene microfibers.

    PubMed

    Haigh, Jodie N; Dargaville, Tim R; Dalton, Paul D

    2017-08-01

    The additive manufacturing of small diameter polypropylene microfibers is described, achieved using a technique termed melt electrospinning writing. Sequential fiber layering, which is important for accurate three-dimensional fabrication, was achieved with the smallest fiber diameter of 16.4±0.2μm obtained. The collector speed, temperature and melt flow rate to the nozzle were optimized for quality and minimal fiber pulsing. Of particular importance to the success of this method is appropriate heating of the collector plate, so that the electrostatically drawn filament adheres during the direct-writing process. By demonstrating the direct-writing of polypropylene, new applications exploiting the favorable mechanical, stability and biocompatible properties of this polymer are envisaged. Copyright © 2017. Published by Elsevier B.V.

  10. Additive manufacturing of tools for lapping glass

    NASA Astrophysics Data System (ADS)

    Williams, Wesley B.

    2013-09-01

    Additive manufacturing technologies have the ability to directly produce parts with complex geometries without the need for secondary processes, tooling or fixtures. This ability was used to produce concave lapping tools with a VFlash 3D printer from 3D Systems. The lapping tools were first designed in Creo Parametric with a defined constant radius and radial groove pattern. The models were converted to stereolithography files which the VFlash used in building the parts, layer by layer, from a UV curable resin. The tools were rotated at 60 rpm and used with 120 grit and 220 grit silicon carbide lapping paste to lap 0.750" diameter fused silica workpieces. The samples developed a matte appearance on the lapped surface that started as a ring at the edge of the workpiece and expanded to the center. This indicated that as material was removed, the workpiece radius was beginning to match the tool radius. The workpieces were then cleaned and lapped on a second tool (with equivalent geometry) using a 3000 grit corundum aluminum oxide lapping paste, until a near specular surface was achieved. By using lapping tools that have been additively manufactured, fused silica workpieces can be lapped to approach a specified convex geometry. This approach may enable more rapid lapping of near net shape workpieces that minimize the material removal required by subsequent polishing. This research may also enable development of new lapping tool geometry and groove patterns for improved loose abrasive finishing.

  11. Laser-based additive manufacturing: where it has been, where it needs to go

    NASA Astrophysics Data System (ADS)

    Cooper, Khershed P.

    2014-03-01

    It is no secret that the laser was the driver for additive manufacturing (AM) of 3D objects since such objects were first demonstrated in the mid-1980s. A myriad of techniques utilizing the directed energy of lasers were invented. Lasers are used to selectively sinter or fuse incremental layers in powder-beds, melt streaming powder following a programmed path, and polymerize photopolymers in a liquid vat layer-by-layer. The laser is an energy source of choice for repair of damaged components, for manufacture of new or replacement parts, and for rapid prototyping of concept designs. Lasers enable microstructure gradients and heterogeneous structures designed to exhibit unique properties and behavior. Laserbased additive manufacturing has been successful in producing relatively simple near net-shape metallic parts saving material and cost, but requiring finish-machining and in repair and refurbishment of worn components. It has been routinely used to produce polymer parts. These capabilities have been widely recognized as evidenced by the explosion in interest in AM technology, nationally. These successes are, however, tempered by challenges facing practitioners such as process and part qualification and verification, which are needed to bring AM as a true manufacturing technology. The ONR manufacturing science program, in collaboration with other agencies, invested in basic R&D in AM since its beginnings. It continues to invest, currently focusing on developing cyber-enabled manufacturing systems for AM. It is believed that such computation, communication and control approaches will help in validating AM and moving it to the factory floor along side CNC machines.

  12. Thermal imaging for assessment of electron-beam freeform fabrication (EBF3) additive manufacturing deposits

    NASA Astrophysics Data System (ADS)

    Zalameda, Joseph N.; Burke, Eric R.; Hafley, Robert A.; Taminger, Karen M.; Domack, Christopher S.; Brewer, Amy; Martin, Richard E.

    2013-05-01

    Additive manufacturing is a rapidly growing field where 3-dimensional parts can be produced layer by layer. NASA's electron beam freeform fabrication (EBF3) technology is being evaluated to manufacture metallic parts in a space environment. The benefits of EBF3 technology are weight savings to support space missions, rapid prototyping in a zero gravity environment, and improved vehicle readiness. The EBF3 system is composed of 3 main components: electron beam gun, multi-axis position system, and metallic wire feeder. The electron beam is used to melt the wire and the multi-axis positioning system is used to build the part layer by layer. To insure a quality deposit, a near infrared (NIR) camera is used to image the melt pool and solidification areas. This paper describes the calibration and application of a NIR camera for temperature measurement. In addition, image processing techniques are presented for deposit assessment metrics.

  13. Reducing the stair step effect of layer manufactured surfaces by ball burnishing

    NASA Astrophysics Data System (ADS)

    Hiegemann, Lars; Agarwal, Chiranshu; Weddeling, Christian; Tekkaya, A. Erman

    2016-10-01

    The layer technology enables fast and flexible additive manufacturing of forming tools. The disadvantages of this system is the formation of stair steps in the range of tool radii. Within this work a new method to smooth this stair steps by ball burnishing is introduced. This includes studies on the general feasibility of the process and the determination of the influence of the rolling parameters. The investigations are carried out experimentally and numerically. Ultimately, the gained knowledge is applied to finish a deep drawing tool which is manufactured by layer technology.

  14. Additive and Photochemical Manufacturing of Copper

    PubMed Central

    Yung, Winco K. C.; Sun, Bo; Meng, Zhengong; Huang, Junfeng; Jin, Yingdi; Choy, Hang Shan; Cai, Zhixiang; Li, Guijun; Ho, Cheuk Lam; Yang, Jinlong; Wong, Wai Yeung

    2016-01-01

    In recent years, 3D printing technologies have been extensively developed, enabling rapid prototyping from a conceptual design to an actual product. However, additive manufacturing of metals in the existing technologies is still cost-intensive and time-consuming. Herein a novel platform for low-cost additive manufacturing is introduced by simultaneously combining the laser-induced forward transfer (LIFT) method with photochemical reaction. Using acrylonitrile butadiene styrene (ABS) polymer as the sacrificial layer, sufficient ejection momentum can be generated in the LIFT method. A low-cost continuous wave (CW) laser diode at 405 nm was utilized and proved to be able to transfer the photochemically synthesized copper onto the target substrate. The wavelength-dependent photochemical behaviour in the LIFT method was verified and characterized by both theoretical and experimental studies compared to 1064 nm fiber laser. The conductivity of the synthesized copper patterns could be enhanced using post electroless plating while retaining the designed pattern shapes. Prototypes of electronic circuits were accordingly built and demonstrated for powering up LEDs. Apart from pristine PDMS materials with low surface energies, the proposed method can simultaneously perform laser-induced forward transfer and photochemical synthesis of metals, starting from their metal oxide forms, onto various target substrates such as polyimide, glass and thermoplastics. PMID:28000733

  15. Additive and Photochemical Manufacturing of Copper

    NASA Astrophysics Data System (ADS)

    Yung, Winco K. C.; Sun, Bo; Meng, Zhengong; Huang, Junfeng; Jin, Yingdi; Choy, Hang Shan; Cai, Zhixiang; Li, Guijun; Ho, Cheuk Lam; Yang, Jinlong; Wong, Wai Yeung

    2016-12-01

    In recent years, 3D printing technologies have been extensively developed, enabling rapid prototyping from a conceptual design to an actual product. However, additive manufacturing of metals in the existing technologies is still cost-intensive and time-consuming. Herein a novel platform for low-cost additive manufacturing is introduced by simultaneously combining the laser-induced forward transfer (LIFT) method with photochemical reaction. Using acrylonitrile butadiene styrene (ABS) polymer as the sacrificial layer, sufficient ejection momentum can be generated in the LIFT method. A low-cost continuous wave (CW) laser diode at 405 nm was utilized and proved to be able to transfer the photochemically synthesized copper onto the target substrate. The wavelength-dependent photochemical behaviour in the LIFT method was verified and characterized by both theoretical and experimental studies compared to 1064 nm fiber laser. The conductivity of the synthesized copper patterns could be enhanced using post electroless plating while retaining the designed pattern shapes. Prototypes of electronic circuits were accordingly built and demonstrated for powering up LEDs. Apart from pristine PDMS materials with low surface energies, the proposed method can simultaneously perform laser-induced forward transfer and photochemical synthesis of metals, starting from their metal oxide forms, onto various target substrates such as polyimide, glass and thermoplastics.

  16. Additive manufacturing techniques for the production of tissue engineering constructs.

    PubMed

    Mota, Carlos; Puppi, Dario; Chiellini, Federica; Chiellini, Emo

    2015-03-01

    'Additive manufacturing' (AM) refers to a class of manufacturing processes based on the building of a solid object from three-dimensional (3D) model data by joining materials, usually layer upon layer. Among the vast array of techniques developed for the production of tissue-engineering (TE) scaffolds, AM techniques are gaining great interest for their suitability in achieving complex shapes and microstructures with a high degree of automation, good accuracy and reproducibility. In addition, the possibility of rapidly producing tissue-engineered constructs meeting patient's specific requirements, in terms of tissue defect size and geometry as well as autologous biological features, makes them a powerful way of enhancing clinical routine procedures. This paper gives an extensive overview of different AM techniques classes (i.e. stereolithography, selective laser sintering, 3D printing, melt-extrusion-based techniques, solution/slurry extrusion-based techniques, and tissue and organ printing) employed for the development of tissue-engineered constructs made of different materials (i.e. polymeric, ceramic and composite, alone or in combination with bioactive agents), by highlighting their principles and technological solutions. Copyright © 2012 John Wiley & Sons, Ltd.

  17. Additive manufactured serialization

    DOEpatents

    Bobbitt, III, John T.

    2017-04-18

    Methods for forming an identifying mark in a structure are described. The method is used in conjunction with an additive manufacturing method and includes the alteration of a process parameter during the manufacturing process. The method can form in a unique identifying mark within or on the surface of a structure that is virtually impossible to be replicated. Methods can provide a high level of confidence that the identifying mark will remain unaltered on the formed structure.

  18. Out of bounds additive manufacturing

    DOE PAGES

    Holshouser, Chris; Newell, Clint; Palas, Sid; ...

    2013-03-01

    Lockheed Martin and Oak Ridge National Laboratory are working on an additive manufacturing system capable of manufacturing components measured not in terms of inches or feet, but multiple yards in all dimensions with the potential to manufacture parts that are completely unbounded in size.

  19. Just-in-time Design and Additive Manufacture of Patient-specific Medical Implants

    NASA Astrophysics Data System (ADS)

    Shidid, Darpan; Leary, Martin; Choong, Peter; Brandt, Milan

    Recent advances in medical imaging and manufacturing science have enabled the design and production of complex, patient-specific orthopaedic implants. Additive Manufacture (AM) generates three-dimensional structures layer by layer, and is not subject to the constraints associated with traditional manufacturing methods. AM provides significant opportunities for the design of novel geometries and complex lattice structures with enhanced functional performance. However, the design and manufacture of patient-specific AM implant structures requires unique expertise in handling various optimization platforms. Furthermore, the design process for complex structures is computationally intensive. The primary aim of this research is to enable the just-in-time customisation of AM prosthesis; whereby AM implant design and manufacture be completed within the time constraints of a single surgical procedure, while minimising prosthesis mass and optimising the lattice structure to match the stiffness of the surrounding bone tissue. In this research, a design approach using raw CT scan data is applied to the AM manufacture of femoral prosthesis. Using the proposed just-in-time concept, the mass of the prosthesis was rapidly designed and manufactured while satisfying the associated structural requirements. Compressive testing of lattice structures manufactured using proposed method shows that the load carrying capacity of the resected composite bone can be recovered by up to 85% and the compressive stiffness of the AM prosthesis is statistically indistinguishable from the stiffness of the initial bone.

  20. Process Modeling and Validation for Metal Big Area Additive Manufacturing

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Simunovic, Srdjan; Nycz, Andrzej; Noakes, Mark W.

    Metal Big Area Additive Manufacturing (mBAAM) is a new additive manufacturing (AM) technology based on the metal arc welding. A continuously fed metal wire is melted by an electric arc that forms between the wire and the substrate, and deposited in the form of a bead of molten metal along the predetermined path. Objects are manufactured one layer at a time starting from the base plate. The final properties of the manufactured object are dependent on its geometry and the metal deposition path, in addition to depending on the basic welding process parameters. Computational modeling can be used to acceleratemore » the development of the mBAAM technology as well as a design and optimization tool for the actual manufacturing process. We have developed a finite element method simulation framework for mBAAM using the new features of software ABAQUS. The computational simulation of material deposition with heat transfer is performed first, followed by the structural analysis based on the temperature history for predicting the final deformation and stress state. In this formulation, we assume that two physics phenomena are coupled in only one direction, i.e. the temperatures are driving the deformation and internal stresses, but their feedback on the temperatures is negligible. The experiment instrumentation (measurement types, sensor types, sensor locations, sensor placements, measurement intervals) and the measurements are presented. The temperatures and distortions from the simulations show good correlation with experimental measurements. Ongoing modeling work is also briefly discussed.« less

  1. Cincinnati Big Area Additive Manufacturing (BAAM)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Duty, Chad E.; Love, Lonnie J.

    Oak Ridge National Laboratory (ORNL) worked with Cincinnati Incorporated (CI) to demonstrate Big Area Additive Manufacturing which increases the speed of the additive manufacturing (AM) process by over 1000X, increases the size of parts by over 10X and shows a cost reduction of over 100X. ORNL worked with CI to transition the Big Area Additive Manufacturing (BAAM) technology from a proof-of-principle (TRL 2-3) demonstration to a prototype product stage (TRL 7-8).

  2. Fabricating Superior NiAl Bronze Components through Wire Arc Additive Manufacturing.

    PubMed

    Ding, Donghong; Pan, Zengxi; van Duin, Stephen; Li, Huijun; Shen, Chen

    2016-08-03

    Cast nickel aluminum bronze (NAB) alloy is widely used for large engineering components in marine applications due to its excellent mechanical properties and corrosion resistance. Casting porosity, as well as coarse microstructure, however, are accompanied by a decrease in mechanical properties of cast NAB components. Although heat treatment, friction stir processing, and fusion welding were implemented to eliminate porosity, improve mechanical properties, and refine the microstructure of as-cast metal, their applications are limited to either surface modification or component repair. Instead of traditional casting techniques, this study focuses on developing NAB components using recently expanded wire arc additive manufacturing (WAAM). Consumable welding wire is melted and deposited layer-by-layer on substrates producing near-net shaped NAB components. Additively-manufactured NAB components without post-processing are fully dense, and exhibit fine microstructure, as well as comparable mechanical properties, to as-cast NAB alloy. The effects of heat input from the welding process and post-weld-heat-treatment (PWHT) are shown to give uniform NAB alloys with superior mechanical properties revealing potential marine applications of the WAAM technique in NAB production.

  3. Fabricating Superior NiAl Bronze Components through Wire Arc Additive Manufacturing

    PubMed Central

    Ding, Donghong; Pan, Zengxi; van Duin, Stephen; Li, Huijun; Shen, Chen

    2016-01-01

    Cast nickel aluminum bronze (NAB) alloy is widely used for large engineering components in marine applications due to its excellent mechanical properties and corrosion resistance. Casting porosity, as well as coarse microstructure, however, are accompanied by a decrease in mechanical properties of cast NAB components. Although heat treatment, friction stir processing, and fusion welding were implemented to eliminate porosity, improve mechanical properties, and refine the microstructure of as-cast metal, their applications are limited to either surface modification or component repair. Instead of traditional casting techniques, this study focuses on developing NAB components using recently expanded wire arc additive manufacturing (WAAM). Consumable welding wire is melted and deposited layer-by-layer on substrates producing near-net shaped NAB components. Additively-manufactured NAB components without post-processing are fully dense, and exhibit fine microstructure, as well as comparable mechanical properties, to as-cast NAB alloy. The effects of heat input from the welding process and post-weld-heat-treatment (PWHT) are shown to give uniform NAB alloys with superior mechanical properties revealing potential marine applications of the WAAM technique in NAB production. PMID:28773774

  4. Structure and properties of parts produced by electron-beam additive manufacturing

    NASA Astrophysics Data System (ADS)

    Klimenov, Vasilii; Klopotov, Anatolii; Fedorov, Vasilii; Abzaev, Yurii; Batranin, Andrey; Kurgan, Kirill; Kairalapov, Daniyar

    2017-12-01

    The paper deals with the study of structure, microstructure, composition and microhardness of a tube processed by electron-beam additive manufacturing using optical and scanning electron microscopy. The structure and macrodefects of a tube made of Grade2 titanium alloy is studied using the X-ray computed tomography. The principles of layer-by-layer assembly and boundaries after powder sintering are set out in this paper. It is found that the titanium alloy has two phases. Future work will involve methods to improve properties of created parts.

  5. Additive Manufacturing of Aerospace Propulsion Components

    NASA Technical Reports Server (NTRS)

    Misra, Ajay K.; Grady, Joseph E.; Carter, Robert

    2015-01-01

    The presentation will provide an overview of ongoing activities on additive manufacturing of aerospace propulsion components, which included rocket propulsion and gas turbine engines. Future opportunities on additive manufacturing of hybrid electric propulsion components will be discussed.

  6. Ultrasonic assessment of additive manufactured Ti-6Al-4V

    NASA Astrophysics Data System (ADS)

    Schehl, Norman; Kramb, Vicki; Dierken, Josiah; Aldrin, John; Schwalbach, Edwin; John, Reji

    2018-04-01

    Additive Manufacturing (AM) processes offer the potential for manufacturing cost savings and rapid insertion into service through production of near net shape components for complicated structures. Use of these parts in high reliability applications such as those in the aerospace industry will require nondestructive characterization methods to ensure post-process material quality in as-built condition. Ultrasonic methods can be used for this quality verification. Depending on the application, the service life of AM components can be sensitive to the part surface condition. The surface roughness and layered structure inherent to the electron-beam powder-bed fusion process necessitates new approaches to evaluate subsurface material integrity in its presence. Experimental methods and data analytics may improve the evaluation of as-built additively manufactured materials. This paper discusses the assessment of additively manufactured EBM Ti-6Al-4V panels using ultrasonic methods and the data analytics applied to evaluate material integrity. The assessment was done as an exploratory study as the discontinuities of interest in these test samples were not known when the measurements were performed. Water immersion ultrasonic techniques, including pulse-echo and through transmission with 10 MHz focused transducers, were used to explore the material integrity of as-built plates. Subsequent destructive mechanical tests of specimens extracted from the plates provided fracture locations indicating critical flaws. To further understand the effect of surface-roughness, an evaluation of ultrasonic response in the presence of as-built surfaces and with the surface removed was performed. The assessment of additive manufactured EBM Ti-6Al-4V panels with ultrasonic techniques indicated that ultrasonic energy was attenuated by the as-built surface roughness. In addition, feature detection was shown to be sensitive to experimental ultrasonic parameters and flaw morphology.

  7. Additive manufactured x-ray optics for astronomy

    NASA Astrophysics Data System (ADS)

    Atkins, Carolyn; Feldman, Charlotte; Brooks, David; Watson, Stephen; Cochrane, William; Roulet, Melanie; Doel, Peter; Willingale, Richard; Hugot, Emmanuel

    2017-08-01

    Additive manufacturing, more commonly known as 3D printing, has become a commercially established technology for rapid prototyping and the fabrication of bespoke intricate parts. Optical components, such as mirrors and lenses, are now being fabricated via additive manufacturing, where the printed substrate is polished in a post-processing step. One application of additively manufactured optics could be within the astronomical X-ray community, where there is a growing need to demonstrate thin, lightweight, high precision optics for a beyond Chandra style mission. This paper will follow a proof-of-concept investigation, sponsored by the UK Space Agency's National Space Technology Programme, into the feasibility of applying additive manufacturing in the production of thin, lightweight, precision X-ray optics for astronomy. One of the benefits of additive manufacturing is the ability to construct intricate lightweighting, which can be optimised to minimise weight while ensuring rigidity. This concept of optimised lightweighting will be applied to a series of polished additively manufactured test samples and experimental data from these samples, including an assessment of the optical quality and the magnitude of any print-through, will be presented. In addition, the finite element analysis optimisations of the lightweighting development will be discussed.

  8. Multi-layer laminate structure and manufacturing method

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Keenihan, James R; Cleereman, Robert J; Eurich, Gerald

    2012-04-24

    The present invention is premised upon a multi-layer laminate structure and method of manufacture, more particularly to a method of constructing the multi-layer laminate structure utilizing a laminate frame and at least one energy activated flowable polymer.

  9. Multi-layer laminate structure and manufacturing method

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Keenihan, James R.; Cleereman, Robert J.; Eurich, Gerald

    2013-01-29

    The present invention is premised upon a multi-layer laminate structure and method of manufacture, more particularly to a method of constructing the multi-layer laminate structure utilizing a laminate frame and at least one energy activated flowable polymer.

  10. Simple scattering analysis and simulation of optical components created by additive manufacturing

    NASA Astrophysics Data System (ADS)

    Rank, M.; Horsak, A.; Heinrich, A.

    2017-10-01

    Additive manufacturing of optical elements is known but still new to the field of optical fabrication. In 3D printers, the parts are deposited layer-by-layer approximating the shape defined in optics design enabling new shapes, which cannot be manufactured using conventional methods. However, the layered structure also causes surface roughness and subsurface scattering, which decrease the quality of optical elements. Illuminating a flat sample with a laser beam, different light distributions are generated on a screen depending on the printing orientation of the sample. Whereas the laser beam is mainly diffused by the samples, a line shaped light distribution can be achieved for a special case in which the laser light goes parallel to the layer structure. These optical effects of 3D printed parts are analyzed using a goniometric setup and fed back into the optics simulation with the goal to improve the design considering the characteristics of the real sample. For a detailed look on the effect, the total scattering is split up into surface contributions and subsurface scattering using index matching techniques to isolate the effects from each other. For an index matched sample with negligible surface effects the line shaped distribution turns into a diffraction pattern which corresponds to the layer thickness of the printer. Finally, an optic simulation with the scattering data is set up for a simple curved sample. The light distribution measured with a robot-based goniophotometer differs from the simulation, because the curvature is approximated by the layer structure. This makes additional analysis necessary.

  11. Online measurement of bead geometry in GMAW-based additive manufacturing using passive vision

    NASA Astrophysics Data System (ADS)

    Xiong, Jun; Zhang, Guangjun

    2013-11-01

    Additive manufacturing based on gas metal arc welding is an advanced technique for depositing fully dense components with low cost. Despite this fact, techniques to achieve accurate control and automation of the process have not yet been perfectly developed. The online measurement of the deposited bead geometry is a key problem for reliable control. In this work a passive vision-sensing system, comprising two cameras and composite filtering techniques, was proposed for real-time detection of the bead height and width through deposition of thin walls. The nozzle to the top surface distance was monitored for eliminating accumulated height errors during the multi-layer deposition process. Various image processing algorithms were applied and discussed for extracting feature parameters. A calibration procedure was presented for the monitoring system. Validation experiments confirmed the effectiveness of the online measurement system for bead geometry in layered additive manufacturing.

  12. Metal Additive Manufacturing: A Review

    NASA Astrophysics Data System (ADS)

    Frazier, William E.

    2014-06-01

    This paper reviews the state-of-the-art of an important, rapidly emerging, manufacturing technology that is alternatively called additive manufacturing (AM), direct digital manufacturing, free form fabrication, or 3D printing, etc. A broad contextual overview of metallic AM is provided. AM has the potential to revolutionize the global parts manufacturing and logistics landscape. It enables distributed manufacturing and the productions of parts-on-demand while offering the potential to reduce cost, energy consumption, and carbon footprint. This paper explores the material science, processes, and business consideration associated with achieving these performance gains. It is concluded that a paradigm shift is required in order to fully exploit AM potential.

  13. Advanced Material Strategies for Next-Generation Additive Manufacturing

    PubMed Central

    Chang, Jinke; He, Jiankang; Zhou, Wenxing; Lei, Qi; Li, Xiao; Li, Dichen

    2018-01-01

    Additive manufacturing (AM) has drawn tremendous attention in various fields. In recent years, great efforts have been made to develop novel additive manufacturing processes such as micro-/nano-scale 3D printing, bioprinting, and 4D printing for the fabrication of complex 3D structures with high resolution, living components, and multimaterials. The development of advanced functional materials is important for the implementation of these novel additive manufacturing processes. Here, a state-of-the-art review on advanced material strategies for novel additive manufacturing processes is provided, mainly including conductive materials, biomaterials, and smart materials. The advantages, limitations, and future perspectives of these materials for additive manufacturing are discussed. It is believed that the innovations of material strategies in parallel with the evolution of additive manufacturing processes will provide numerous possibilities for the fabrication of complex smart constructs with multiple functions, which will significantly widen the application fields of next-generation additive manufacturing. PMID:29361754

  14. Advanced Material Strategies for Next-Generation Additive Manufacturing.

    PubMed

    Chang, Jinke; He, Jiankang; Mao, Mao; Zhou, Wenxing; Lei, Qi; Li, Xiao; Li, Dichen; Chua, Chee-Kai; Zhao, Xin

    2018-01-22

    Additive manufacturing (AM) has drawn tremendous attention in various fields. In recent years, great efforts have been made to develop novel additive manufacturing processes such as micro-/nano-scale 3D printing, bioprinting, and 4D printing for the fabrication of complex 3D structures with high resolution, living components, and multimaterials. The development of advanced functional materials is important for the implementation of these novel additive manufacturing processes. Here, a state-of-the-art review on advanced material strategies for novel additive manufacturing processes is provided, mainly including conductive materials, biomaterials, and smart materials. The advantages, limitations, and future perspectives of these materials for additive manufacturing are discussed. It is believed that the innovations of material strategies in parallel with the evolution of additive manufacturing processes will provide numerous possibilities for the fabrication of complex smart constructs with multiple functions, which will significantly widen the application fields of next-generation additive manufacturing.

  15. Design and additive manufacture for flow chemistry.

    PubMed

    Capel, Andrew J; Edmondson, Steve; Christie, Steven D R; Goodridge, Ruth D; Bibb, Richard J; Thurstans, Matthew

    2013-12-07

    We review the use of additive manufacturing (AM) as a novel manufacturing technique for the production of milli-scale reactor systems. Five well-developed additive manufacturing techniques: stereolithography (SL), multi-jet modelling (MJM), selective laser melting (SLM), laser sintering (LS) and fused deposition modelling (FDM) were used to manufacture a number of miniaturised reactors which were tested using a range of organic and inorganic reactions.

  16. Additive manufacturing: Toward holistic design

    DOE PAGES

    Jared, Bradley H.; Aguilo, Miguel A.; Beghini, Lauren L.; ...

    2017-03-18

    Here, additive manufacturing offers unprecedented opportunities to design complex structures optimized for performance envelopes inaccessible under conventional manufacturing constraints. Additive processes also promote realization of engineered materials with microstructures and properties that are impossible via traditional synthesis techniques. Enthused by these capabilities, optimization design tools have experienced a recent revival. The current capabilities of additive processes and optimization tools are summarized briefly, while an emerging opportunity is discussed to achieve a holistic design paradigm whereby computational tools are integrated with stochastic process and material awareness to enable the concurrent optimization of design topologies, material constructs and fabrication processes.

  17. Additive manufacturing of transparent fused quartz

    NASA Astrophysics Data System (ADS)

    Luo, Junjie; Hostetler, John M.; Gilbert, Luke; Goldstein, Jonathan T.; Urbas, Augustine M.; Bristow, Douglas A.; Landers, Robert G.; Kinzel, Edward C.

    2018-04-01

    This paper investigates a filament-fed process for additive manufacturing (AM) of fused quartz. Glasses such as fused quartz have significant scientific and engineering applications, which include optics, communications, electronics, and hermetic seals. AM has several attractive benefits such as increased design freedom, faster prototyping, and lower processing costs for small production volumes. However, current research into glass AM has focused primarily on nonoptical applications. Fused quartz is studied here because of its desirability for use in high-quality optics due to its high transmissivity and thermal stability. Fused quartz filaments are fed into a CO2 laser-generated molten region, smoothly depositing material onto the workpiece. Spectroscopy and pyrometry are used to measure the thermal radiation incandescently emitted from the molten region. The effects of the laser power and scan speed are determined by measuring the morphology of single tracks. Thin walls are printed to study the effects of layer-to-layer height. This information is used to deposit solid pieces including a cylindrical-convex shape capable of focusing visible light. The transmittance and index homogeneity of the printed fused quartz are measured. These results show that the filament-fed process has the potential to print transmissive optics.

  18. Additive Manufacturing: Unlocking the Evolution of Energy Materials

    PubMed Central

    Zhakeyev, Adilet; Wang, Panfeng; Shu, Wenmiao; Wang, Huizhi

    2017-01-01

    Abstract The global energy infrastructure is undergoing a drastic transformation towards renewable energy, posing huge challenges on the energy materials research, development and manufacturing. Additive manufacturing has shown its promise to change the way how future energy system can be designed and delivered. It offers capability in manufacturing complex 3D structures, with near‐complete design freedom and high sustainability due to minimal use of materials and toxic chemicals. Recent literatures have reported that additive manufacturing could unlock the evolution of energy materials and chemistries with unprecedented performance in the way that could never be achieved by conventional manufacturing techniques. This comprehensive review will fill the gap in communicating on recent breakthroughs in additive manufacturing for energy material and device applications. It will underpin the discoveries on what 3D functional energy structures can be created without design constraints, which bespoke energy materials could be additively manufactured with customised solutions, and how the additively manufactured devices could be integrated into energy systems. This review will also highlight emerging and important applications in energy additive manufacturing, including fuel cells, batteries, hydrogen, solar cell as well as carbon capture and storage. PMID:29051861

  19. Additive Manufacturing: Unlocking the Evolution of Energy Materials.

    PubMed

    Zhakeyev, Adilet; Wang, Panfeng; Zhang, Li; Shu, Wenmiao; Wang, Huizhi; Xuan, Jin

    2017-10-01

    The global energy infrastructure is undergoing a drastic transformation towards renewable energy, posing huge challenges on the energy materials research, development and manufacturing. Additive manufacturing has shown its promise to change the way how future energy system can be designed and delivered. It offers capability in manufacturing complex 3D structures, with near-complete design freedom and high sustainability due to minimal use of materials and toxic chemicals. Recent literatures have reported that additive manufacturing could unlock the evolution of energy materials and chemistries with unprecedented performance in the way that could never be achieved by conventional manufacturing techniques. This comprehensive review will fill the gap in communicating on recent breakthroughs in additive manufacturing for energy material and device applications. It will underpin the discoveries on what 3D functional energy structures can be created without design constraints, which bespoke energy materials could be additively manufactured with customised solutions, and how the additively manufactured devices could be integrated into energy systems. This review will also highlight emerging and important applications in energy additive manufacturing, including fuel cells, batteries, hydrogen, solar cell as well as carbon capture and storage.

  20. Thermal Imaging for Assessment of Electron-Beam Free Form Fabrication (EBF(sup 3)) Additive Manufacturing Welds

    NASA Technical Reports Server (NTRS)

    Zalameda, Joseph N.; Burke, Eric R.; Hafley, Robert A.; Taminger, Karen M.; Domack, Christopher S.; Brewer, Amy R.; Martin, Richard E.

    2013-01-01

    Additive manufacturing is a rapidly growing field where 3-dimensional parts can be produced layer by layer. NASA s electron beam free-form fabrication (EBF(sup 3)) technology is being evaluated to manufacture metallic parts in a space environment. The benefits of EBF(sup 3) technology are weight savings to support space missions, rapid prototyping in a zero gravity environment, and improved vehicle readiness. The EBF(sup 3) system is composed of 3 main components: electron beam gun, multi-axis position system, and metallic wire feeder. The electron beam is used to melt the wire and the multi-axis positioning system is used to build the part layer by layer. To insure a quality weld, a near infrared (NIR) camera is used to image the melt pool and solidification areas. This paper describes the calibration and application of a NIR camera for temperature measurement. In addition, image processing techniques are presented for weld assessment metrics.

  1. Effusion plate using additive manufacturing methods

    DOEpatents

    Johnson, Thomas Edward; Keener, Christopher Paul; Ostebee, Heath Michael; Wegerif, Daniel Gerritt

    2016-04-12

    Additive manufacturing techniques may be utilized to construct effusion plates. Such additive manufacturing techniques may include defining a configuration for an effusion plate having one or more internal cooling channels. The manufacturing techniques may further include depositing a powder into a chamber, applying an energy source to the deposited powder, and consolidating the powder into a cross-sectional shape corresponding to the defined configuration. Such methods may be implemented to construct an effusion plate having one or more channels with a curved cross-sectional geometry.

  2. Harnessing the Potential of Additive Manufacturing

    DTIC Science & Technology

    2016-12-01

    manufacturing age, which is dominated by standards for materials, processes and process control. Conventional manufacturing is based upon a design that is...documented either in a drawing or a computer-aided design (CAD) file. The manufacturing team then develops a docu- mented public or private process for...31 Defense AT&L: November-December 2016 Harnessing the Potential of Additive Manufacturing Bill Decker Decker is director of Technology

  3. Report From BPTCS Project Team On Evaluation Of Additive Manufacturing For Pressure Retaining Equipment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rawls, G.

    ASME is evaluating the use of additive manufacturing (AM) for the construction of pressure equipment. The information in this report assesses available AM technologies for direct metal fabrication of pressure equipment. Background information is included in the report to provide context for those not experienced in AM technology. Only commercially available technologies for direct metal fabrication are addressed in the report because these AM methods are the only viable approaches for the construction of pressure equipment. Metal AM technologies can produce near-net shape parts by using multiple layers of material from a three dimensional (3D) design model of the geometry.more » Additive manufacturing of metal components was developed from polymer based rapid prototyping or 3D printing. At the current maturity level, AM application for pressure equipment has the potential to reduce delivery times and costs for complex shapes. AM will also lead to a reduction in the use of high cost materials, since parts can be created with corrosion resistant layers of high alloy material and structural layers of lower cost materials.« less

  4. Process Control and Development for Ultrasonic Additive Manufacturing with Embedded Fibers

    NASA Astrophysics Data System (ADS)

    Hehr, Adam J.

    Ultrasonic additive manufacturing (UAM) is a recent additive manufacturing technology which combines ultrasonic metal welding, CNC machining, and mechanized foil layering to create large gapless near net-shape metallic parts. The process has been attracting much attention lately due to its low formation temperature, the capability to join dissimilar metals, and the ability to create complex design features not possible with traditional subtractive processes alone. These process attributes enable light-weighting of structures and components in an unprecedented way. However, UAM is currently limited to niche areas due to the lack of quality tracking and inadequate scientific understanding of the process. As a result, this thesis work is focused on improving both component quality tracking and process understanding through the use of average electrical power input to the welder. Additionally, the understanding and application space of embedding fibers into metals using UAM is investigated, with particular focus on NiTi shape memory alloy fibers.

  5. Advances in High Temperature Materials for Additive Manufacturing

    NASA Astrophysics Data System (ADS)

    Nordin, Nurul Amira Binti; Johar, Muhammad Akmal Bin; Ibrahim, Mohd Halim Irwan Bin; Marwah, Omar Mohd Faizan bin

    2017-08-01

    In today’s technology, additive manufacturing has evolved over the year that commonly known as 3D printing. Currently, additive manufacturing have been applied for many industries such as for automotive, aerospace, medical and other commercial product. The technologies are supported by materials for the manufacturing process to produce high quality product. Plus, additive manufacturing technologies has been growth from the lowest to moderate and high technology to fulfil manufacturing industries obligation. Initially from simple 3D printing such as fused deposition modelling (FDM), poly-jet, inkjet printing, to selective laser sintering (SLS), and electron beam melting (EBM). However, the high technology of additive manufacturing nowadays really needs high investment to carry out the process for fine products. There are three foremost type of material which is polymer, metal and ceramic used for additive manufacturing application, and mostly they were in the form of wire feedstock or powder. In circumstance, it is crucial to recognize the characteristics of each type of materials used in order to understand the behaviours of the materials on high temperature application via additive manufacturing. Therefore, this review aims to provide excessive inquiry and gather the necessary information for further research on additive material materials for high temperature application. This paper also proposed a new material based on powder glass, which comes from recycled tempered glass from automotive industry, having a huge potential to be applied for high temperature application. The technique proposed for additive manufacturing will minimize some cost of modelling with same quality of products compare to the others advanced technology used for high temperature application.

  6. Selection of Additive Manufacturing (AM) Equipment

    DTIC Science & Technology

    2017-04-01

    in the design , test, and fabrication of the systems within the AMRDEC portfolio. 14. SUBJECT TERMS Additive Manufacturing (AM), Fused Deposition...tools in the design and development of AMRDEC products .   Figure 1. Stratasys Objet Connex3 [1] While these machines and technologies have...TECHNICAL REPORT RDMR-WD-16-87 SELECTION OF ADDITIVE MANUFACTURING (AM) EQUIPMENT Lance E. Hall Weapons Development

  7. A comparative study of additive and subtractive manufacturing for dental restorations.

    PubMed

    Bae, Eun-Jeong; Jeong, Il-Do; Kim, Woong-Chul; Kim, Ji-Hwan

    2017-08-01

    revealed a fine linear gap between the layers of restorations fabricated using stereolithography apparatus and a grooved hole with inconsistent weak scratches when fabricated using selective laser sintering. In the wax and zirconia restorations, possible traces of milling bur passes were observed. The results indicate that the accuracy of dental restorations fabricated using the additive manufacturing methods is higher than that of subtractive methods. Therefore, additive manufacturing methods are a viable alternative to subtractive methods. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  8. Laser polishing of additive manufactured Ti alloys

    NASA Astrophysics Data System (ADS)

    Ma, C. P.; Guan, Y. C.; Zhou, W.

    2017-06-01

    Laser-based additive manufacturing has attracted much attention as a promising 3D printing method for metallic components in recent years. However, surface roughness of additive manufactured components has been considered as a challenge to achieve high performance. In this work, we demonstrate the capability of fiber laser in polishing rough surface of additive manufactured Ti-based alloys as Ti-6Al-4V and TC11. Both as-received surface and laser-polished surfaces as well as cross-section subsurfaces were analyzed carefully by White-Light Interference, Confocal Microscope, Focus Ion Beam, Scanning Electron Microscopy, Energy Dispersive Spectrometer, and X-ray Diffraction. Results revealed that as-received Ti-based alloys with surface roughness more than 5 μm could be reduce to less than 1 μm through laser polishing process. Moreover, microstructure, microhardness and wear resistance of laser-polished zone was investigated in order to examine the thermal effect of laser polishing processing on the substrate of additive manufactured Ti alloys. This proof-of-concept process has the potential to effectively improve the surface roughness of additive manufactured metallic alloy by local polishing method without damage to the substrate.

  9. Measurement of fracture toughness of metallic materials produced by additive manufacturing

    NASA Astrophysics Data System (ADS)

    Quénard, O.; Dorival, O.; Guy, Ph.; Votié, A.; Brethome, K.

    2018-04-01

    This study focuses on the microstructure and mechanical properties of metallic materials produced by additive layer manufacturing (ALM), especially the laser beam melting process. The influence of the specimen orientation during the ALM process and that of two post-build thermal treatments were investigated. The identified metal powder is Ti-6Al-4V (titanium base). Metallographic analysis shows their effects on the microstructure of the metals. Mechanical experiments involving tensile tests as well as toughness tests were performed according to ASTM (American Society for Testing and Materials) norms. The results show that the main influence is that of the thermal treatments; however the manufacturing stacking direction may lead to some anisotropy in the mechanical properties.

  10. Microstructural Analysis of Ti-6Al-4V Components Made by Electron Beam Additive Manufacturing

    NASA Astrophysics Data System (ADS)

    Coleman, Rashadd L.

    Electron Beam Additive Manufacturing (EBAM) is a relatively new additive manufacturing (AM) technology that uses a high-energy electron beam to melt and fuse powders to build full-density parts in a layer by layer fashion. EBAM can fabricate metallic components, particularly, of complex shapes, in an efficient and cost-effective manner compared to conventional manufacturing means. EBAM is an enabling technology for rapid manufacturing (RM) of metallic components, and thus, can efficiently integrate the design and manufacturing of aerospace components. However, EBAM for aerospace-related applications remain limited because the effect of the EBAM process on part characteristics is not fully understood. In this study, various techniques including microhardness, optical microscopy (OM), X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), and electron backscatter diffraction (EBSD) were used to characterize Ti-6Al-4V components processed using EBAM. The results were compared to Ti-6Al-4V components processed using conventional techniques. In this study it is shown that EBAM built Ti-64 components have increased hardness, elastic modulus, and yield strength compared to wrought Ti-6Al-4V. Further, it is also shown in this study that the horizontal build EBAM Ti-6Al-4V has increased hardness, elastic modulus, and yield strength compared to vertical build EBAM due to a preferential growth of the beta phase.

  11. Polymers for 3D Printing and Customized Additive Manufacturing.

    PubMed

    Ligon, Samuel Clark; Liska, Robert; Stampfl, Jürgen; Gurr, Matthias; Mülhaupt, Rolf

    2017-08-09

    Additive manufacturing (AM) alias 3D printing translates computer-aided design (CAD) virtual 3D models into physical objects. By digital slicing of CAD, 3D scan, or tomography data, AM builds objects layer by layer without the need for molds or machining. AM enables decentralized fabrication of customized objects on demand by exploiting digital information storage and retrieval via the Internet. The ongoing transition from rapid prototyping to rapid manufacturing prompts new challenges for mechanical engineers and materials scientists alike. Because polymers are by far the most utilized class of materials for AM, this Review focuses on polymer processing and the development of polymers and advanced polymer systems specifically for AM. AM techniques covered include vat photopolymerization (stereolithography), powder bed fusion (SLS), material and binder jetting (inkjet and aerosol 3D printing), sheet lamination (LOM), extrusion (FDM, 3D dispensing, 3D fiber deposition, and 3D plotting), and 3D bioprinting. The range of polymers used in AM encompasses thermoplastics, thermosets, elastomers, hydrogels, functional polymers, polymer blends, composites, and biological systems. Aspects of polymer design, additives, and processing parameters as they relate to enhancing build speed and improving accuracy, functionality, surface finish, stability, mechanical properties, and porosity are addressed. Selected applications demonstrate how polymer-based AM is being exploited in lightweight engineering, architecture, food processing, optics, energy technology, dentistry, drug delivery, and personalized medicine. Unparalleled by metals and ceramics, polymer-based AM plays a key role in the emerging AM of advanced multifunctional and multimaterial systems including living biological systems as well as life-like synthetic systems.

  12. Polymers for 3D Printing and Customized Additive Manufacturing

    PubMed Central

    2017-01-01

    Additive manufacturing (AM) alias 3D printing translates computer-aided design (CAD) virtual 3D models into physical objects. By digital slicing of CAD, 3D scan, or tomography data, AM builds objects layer by layer without the need for molds or machining. AM enables decentralized fabrication of customized objects on demand by exploiting digital information storage and retrieval via the Internet. The ongoing transition from rapid prototyping to rapid manufacturing prompts new challenges for mechanical engineers and materials scientists alike. Because polymers are by far the most utilized class of materials for AM, this Review focuses on polymer processing and the development of polymers and advanced polymer systems specifically for AM. AM techniques covered include vat photopolymerization (stereolithography), powder bed fusion (SLS), material and binder jetting (inkjet and aerosol 3D printing), sheet lamination (LOM), extrusion (FDM, 3D dispensing, 3D fiber deposition, and 3D plotting), and 3D bioprinting. The range of polymers used in AM encompasses thermoplastics, thermosets, elastomers, hydrogels, functional polymers, polymer blends, composites, and biological systems. Aspects of polymer design, additives, and processing parameters as they relate to enhancing build speed and improving accuracy, functionality, surface finish, stability, mechanical properties, and porosity are addressed. Selected applications demonstrate how polymer-based AM is being exploited in lightweight engineering, architecture, food processing, optics, energy technology, dentistry, drug delivery, and personalized medicine. Unparalleled by metals and ceramics, polymer-based AM plays a key role in the emerging AM of advanced multifunctional and multimaterial systems including living biological systems as well as life-like synthetic systems. PMID:28756658

  13. Numerical simulation of residual stress in laser based additive manufacturing process

    NASA Astrophysics Data System (ADS)

    Kalyan Panda, Bibhu; Sahoo, Seshadev

    2018-03-01

    Minimizing the residual stress build-up in metal-based additive manufacturing plays a pivotal role in selecting a particular material and technique for making an industrial part. In beam-based additive manufacturing, although a great deal of effort has been made to minimize the residual stresses, it is still elusive how to do so by simply optimizing the processing parameters, such as beam size, beam power, and scan speed. Amid different types of additive manufacturing processes, Direct Metal Laser Sintering (DMLS) process uses a high-power laser to melt and sinter layers of metal powder. The rapid solidification and heat transfer on powder bed endows a high cooling rate which leads to the build-up of residual stresses, that will affect the mechanical properties of the build parts. In the present work, the authors develop a numerical thermo-mechanical model for the measurement of residual stress in the AlSi10Mg build samples by using finite element method. Transient temperature distribution in the powder bed was assessed using the coupled thermal to structural model. Subsequently, the residual stresses were estimated with varying laser power. From the simulation result, it found that the melt pool dimensions increase with increasing the laser power and the magnitude of residual stresses in the built part increases.

  14. Building a Competitive Edge with Additive Manufacturing

    DTIC Science & Technology

    2013-02-14

    construct ceramic molds for complex metal parts using a 3D printing technique. They estimate the new 6 technique could eliminate all of the...processes. They include 3D printing and Additive Beam Techniques.15 Most Additive Manufacturing techniques are specific to certain classes of materials...9 Example Additive Manufacturing Techniques16 3D Printing Additive Beam Stereolithography (SLA) Direct Metal Laser Sintering (DMLS

  15. Laser Additive Manufacturing of Magnetic Materials

    NASA Astrophysics Data System (ADS)

    Mikler, C. V.; Chaudhary, V.; Borkar, T.; Soni, V.; Jaeger, D.; Chen, X.; Contieri, R.; Ramanujan, R. V.; Banerjee, R.

    2017-03-01

    While laser additive manufacturing is becoming increasingly important in the context of next-generation manufacturing technologies, most current research efforts focus on optimizing process parameters for the processing of mature alloys for structural applications (primarily stainless steels, titanium base, and nickel base alloys) from pre-alloyed powder feedstocks to achieve properties superior to conventionally processed counterparts. However, laser additive manufacturing or processing can also be applied to functional materials. This article focuses on the use of directed energy deposition-based additive manufacturing technologies, such as the laser engineered net shaping (LENS™) process, to deposit magnetic alloys. Three case studies are presented: Fe-30 at.%Ni, permalloys of the type Ni-Fe-V and Ni-Fe-Mo, and Fe-Si-B-Cu-Nb (derived from Finemet) alloys. All these alloys have been processed from a blend of elemental powders used as the feedstock, and their resultant microstructures, phase formation, and magnetic properties are discussed in this paper. Although these alloys were produced from a blend of elemental powders, they exhibited relatively uniform microstructures and comparable magnetic properties to those of their conventionally processed counterparts.

  16. Cleaning and Cleanliness Measurement of Additive Manufactured Parts

    NASA Technical Reports Server (NTRS)

    Mitchell, Mark A.; Edwards, Kevin; Fox, Eric; Boothe, Richard

    2017-01-01

    Additive Manufacturing processes allow for the manufacture of complex three dimensional components that otherwise could not be manufactured. Post treatment processes require the removal of any remnant bulk powder that may become entrapped within small cavities and channels within a component. This project focuses on several gross cleaning methods and the verification metrics associated with additive manufactured parts for oxygen propulsion usage.

  17. One-step volumetric additive manufacturing of complex polymer structures

    DOE PAGES

    Shusteff, Maxim; Browar, Allison E. M.; Kelly, Brett E.; ...

    2017-12-01

    Two limitations of additive manufacturing methods that arise from layer-based fabrication are slow speed and geometric constraints (which include poor surface quality). Both limitations are overcome in the work reported here, introducing a new volumetric additive fabrication paradigm that produces photopolymer structures with complex non-periodic 3D geometries on a timescale of seconds. We implement this approach using holographic patterning of light fields, demonstrate the fabrication of a variety of structures, and study the properties of the light patterns and photosensitive resins required for this fabrication approach. The results indicate that lowabsorbing resins containing ~0.1% photoinitiator, illuminated at modest powers (~10-100more » mW) may be successfully used to build full structures in ~1-10 s.« less

  18. One-step volumetric additive manufacturing of complex polymer structures

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shusteff, Maxim; Browar, Allison E. M.; Kelly, Brett E.

    Two limitations of additive manufacturing methods that arise from layer-based fabrication are slow speed and geometric constraints (which include poor surface quality). Both limitations are overcome in the work reported here, introducing a new volumetric additive fabrication paradigm that produces photopolymer structures with complex non-periodic 3D geometries on a timescale of seconds. We implement this approach using holographic patterning of light fields, demonstrate the fabrication of a variety of structures, and study the properties of the light patterns and photosensitive resins required for this fabrication approach. The results indicate that lowabsorbing resins containing ~0.1% photoinitiator, illuminated at modest powers (~10-100more » mW) may be successfully used to build full structures in ~1-10 s.« less

  19. One-step volumetric additive manufacturing of complex polymer structures

    PubMed Central

    Shusteff, Maxim; Browar, Allison E. M.; Kelly, Brett E.; Henriksson, Johannes; Weisgraber, Todd H.; Panas, Robert M.; Fang, Nicholas X.; Spadaccini, Christopher M.

    2017-01-01

    Two limitations of additive manufacturing methods that arise from layer-based fabrication are slow speed and geometric constraints (which include poor surface quality). Both limitations are overcome in the work reported here, introducing a new volumetric additive fabrication paradigm that produces photopolymer structures with complex nonperiodic three-dimensional geometries on a time scale of seconds. We implement this approach using holographic patterning of light fields, demonstrate the fabrication of a variety of structures, and study the properties of the light patterns and photosensitive resins required for this fabrication approach. The results indicate that low-absorbing resins containing ~0.1% photoinitiator, illuminated at modest powers (~10 to 100 mW), may be successfully used to build full structures in ~1 to 10 s. PMID:29230437

  20. One-step volumetric additive manufacturing of complex polymer structures.

    PubMed

    Shusteff, Maxim; Browar, Allison E M; Kelly, Brett E; Henriksson, Johannes; Weisgraber, Todd H; Panas, Robert M; Fang, Nicholas X; Spadaccini, Christopher M

    2017-12-01

    Two limitations of additive manufacturing methods that arise from layer-based fabrication are slow speed and geometric constraints (which include poor surface quality). Both limitations are overcome in the work reported here, introducing a new volumetric additive fabrication paradigm that produces photopolymer structures with complex nonperiodic three-dimensional geometries on a time scale of seconds. We implement this approach using holographic patterning of light fields, demonstrate the fabrication of a variety of structures, and study the properties of the light patterns and photosensitive resins required for this fabrication approach. The results indicate that low-absorbing resins containing ~0.1% photoinitiator, illuminated at modest powers (~10 to 100 mW), may be successfully used to build full structures in ~1 to 10 s.

  1. Finishing of additively manufactured titanium alloy by shape adaptive grinding (SAG)

    NASA Astrophysics Data System (ADS)

    Beaucamp, Anthony T.; Namba, Yoshiharu; Charlton, Phillip; Jain, Samyak; Graziano, Arthur A.

    2015-06-01

    In recent years, rapid prototyping of titanium alloy components for medical and aeronautics application has become viable thanks to advances in technologies such as electron beam melting (EBM) and selective laser sintering (SLS). However, for many applications the high surface roughness generated by additive manufacturing techniques demands a post-finishing operation to improve the surface quality prior to usage. In this paper, the novel shape adaptive grinding process has been applied to finishing titanium alloy (Ti6Al4V) additively manufactured by EBM and SLS. It is shown that the micro-structured surface layer resulting from the melting process can be removed, and the surface can then be smoothed down to less than 10 nm Ra (starting from 4-5 μm Ra) using only three different diamond grit sizes. This paper also demonstrates application of the technology to freeform shapes, and documents the dimensional accuracy of finished artifacts.

  2. Additive Manufacturing Integrated Energy Demonstration

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jackson, Roderick; Lee, Brian; Love, Lonnie

    2016-02-05

    Meet AMIE - the Additive Manufacturing Integrated Energy demonstration project. Led by Oak Ridge National Laboratory and many industry partners, the AMIE project changes the way we think about generating, storing, and using electrical power. AMIE uses an integrated energy system that shares energy between a building and a vehicle. And, utilizing advanced manufacturing and rapid innovation, it only took one year from concept to launch.

  3. Additive Manufacturing Integrated Energy Demonstration

    ScienceCinema

    Jackson, Roderick; Lee, Brian; Love, Lonnie; Mabe, Gavin; Keller, Martin; Curran, Scott; Chinthavali, Madhu; Green, Johney; Sawyer, Karma; Enquist, Phil

    2018-01-16

    Meet AMIE - the Additive Manufacturing Integrated Energy demonstration project. Led by Oak Ridge National Laboratory and many industry partners, the AMIE project changes the way we think about generating, storing, and using electrical power. AMIE uses an integrated energy system that shares energy between a building and a vehicle. And, utilizing advanced manufacturing and rapid innovation, it only took one year from concept to launch.

  4. America Makes: National Additive Manufacturing Innovation Institute (NAMII) Project 1: Nondestructive Evaluation (NDE) of Complex Metallic Additive Manufactured (AM) Structures

    DTIC Science & Technology

    2014-06-01

    layer-by-layer manufacturing of a component by using PBF processes is accompanied by the establishment of a unidirectional heat transfer along the build...direction. Because grain growth during solidification preferably occurs in the opposite direction of heat transfer , the formation of elongated...development and deployment of phased array technology.[69] Phased array ultrasonic (PAUT) sensors use multiple elements instead of a single element

  5. Simulation of Powder Layer Deposition in Additive Manufacturing Processes Using the Discrete Element Method

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Herbold, E. B.; Walton, O.; Homel, M. A.

    2015-10-26

    This document serves as a final report to a small effort where several improvements were added to a LLNL code GEODYN-­L to develop Discrete Element Method (DEM) algorithms coupled to Lagrangian Finite Element (FE) solvers to investigate powder-­bed formation problems for additive manufacturing. The results from these simulations will be assessed for inclusion as the initial conditions for Direct Metal Laser Sintering (DMLS) simulations performed with ALE3D. The algorithms were written and performed on parallel computing platforms at LLNL. The total funding level was 3-­4 weeks of an FTE split amongst two staff scientists and one post-­doc. The DEM simulationsmore » emulated, as much as was feasible, the physical process of depositing a new layer of powder over a bed of existing powder. The DEM simulations utilized truncated size distributions spanning realistic size ranges with a size distribution profile consistent with realistic sample set. A minimum simulation sample size on the order of 40-­particles square by 10-­particles deep was utilized in these scoping studies in order to evaluate the potential effects of size segregation variation with distance displaced in front of a screed blade. A reasonable method for evaluating the problem was developed and validated. Several simulations were performed to show the viability of the approach. Future investigations will focus on running various simulations investigating powder particle sizing and screen geometries.« less

  6. Transparent Conductive Ink for Additive Manufacturing

    NASA Technical Reports Server (NTRS)

    Patlan, X. J.; Rolin, T. D.

    2017-01-01

    NASA analyzes, tests, packages, and fabricates electrical, electronic, and electromechanical (EEE) parts. Nanotechnology is listed in NASA's Technology Roadmap as a key area to invest for further development.1 This research project focused on using nanotechnology to improve electroluminescent lighting in terms of additive manufacturing and to increase energy efficiency. Specifically, this project's goal was to produce a conductive but transparent printable ink that can be sprayed on any surface for use as one of the electrodes in electroluminescent device design. This innovative work is known as thick film dielectric electroluminescent (TDEL) technology. TDEL devices are used for "backlighting, illumination, and identification due to their tunable color output, scalability, and efficiency" (I.K. Small, T.D. Rolin, and A.D. Shields, "3D Printed Electroluminescent Light Panels," NASA Fiscal Year 2017 Center Innovation Fund Proposal, unpublished data, 2017). These devices use a 'front-to-back' printing method, where the substrate is the transparent layer, and the dielectric and phosphor are layered on top. This project is a first step in the process of creating a 3D printable 'back-to-front' electroluminescent device. Back-to-front 3D-printed devices are beneficial because they can be printed onto different substrates and embedded in different surfaces, and the substrate is not required to be transparent, all because the light is emitted from the top surface through the transparent conductor. Advances in this area will help further development of printing TDEL devices on an array of different surfaces. Figure 1 demonstrates the layering of the two electrodes that are aligned in a parallel plate capacitor structure (I.K. Small, T.D. Rolin, and A.D. Shields, "3D Printed Electroluminescent Light Panels," NASA Fiscal Year 2017 Center Innovation Fund Proposal, unpublished data, 2017). Voltage is applied across the device, and the subsequent electron excitation results in

  7. Additive manufacturing of tunable lenses

    NASA Astrophysics Data System (ADS)

    Schlichting, Katja; Novak, Tobias; Heinrich, Andreas

    2017-02-01

    Individual additive manufacturing of optical systems based on 3D Printing offers varied possibilities in design and usage. In addition to the additive manufacturing procedure, the usage of tunable lenses allows further advantages for intelligent optical systems. Our goal is to bring the advantages of additive manufacturing together with the huge potential of tunable lenses. We produced tunable lenses as a bundle without any further processing steps, like polishing. The lenses were designed and directly printed with a 3D Printer as a package. The design contains the membrane as an optical part as well as the mechanical parts of the lens, like the attachments for the sleeves which contain the oil. The dynamic optical lenses were filled with an oil. The focal length of the lenses changes due to a change of the radius of curvature. This change is caused by changing the pressure in the inside of the lens. In addition to that, we designed lenses with special structures to obtain different areas with an individual optical power. We want to discuss the huge potential of this technology for several applications. Further, an appropriate controlling system is needed. Wéll show the possibilities to control and regulate the optical power of the lenses. The lenses could be used for illumination tasks, and in the future, for individual measurement tasks. The main advantage is the individuality and the possibility to create an individual design which completely fulfills the requirements for any specific application.

  8. Initiatives to Improve Quality of Additively Manufactured Parts

    NASA Technical Reports Server (NTRS)

    Waller, Jess; Nichols, Charles

    2017-01-01

    NASA is providing leadership in an international effort linking government and industry resources to speed adoption of additive manufactured (AM) parts. Participants include government agencies (NASA, USAF, NIST, FAA), industry (commercial aerospace, NDE manufacturers, AM equipment manufacturers), standards organizations and academia. NASA is also partnering with its international space exploration organizations such as ESA and JAXA. NDT is identified as a universal need for all aspects of additive manufacturing.

  9. Cleaning Process Development for Metallic Additively Manufactured Parts

    NASA Technical Reports Server (NTRS)

    Tramel, Terri L.; Welker, Roger; Lowery, Niki; Mitchell, Mark

    2014-01-01

    Additive Manufacturing of metallic components for aerospace applications offers many advantages over traditional manufacturing techniques. As a new technology, many aspects of its widespread utilization remain open to investigation. Among these are the cleaning processes that can be used for post finishing of parts and measurements to verify effectiveness of the cleaning processes. Many cleaning and drying processes and measurement methods that have been used for parts manufactured using conventional techniques are candidates that may be considered for cleaning and verification of additively manufactured parts. Among these are vapor degreasing, ultrasonic immersion and spray cleaning, followed by hot air drying, vacuum baking and solvent displacement drying. Differences in porosity, density, and surface finish of additively manufactured versus conventionally manufactured parts may introduce new considerations in the selection of cleaning and drying processes or the method used to verify their effectiveness. This presentation will review the relative strengths and weaknesses of different candidate cleaning and drying processes as they may apply to additively manufactured metal parts for aerospace applications. An ultrasonic cleaning technique for exploring the cleanability of parts will be presented along with an example using additively manufactured Inconel 718 test specimens to illustrate its use. The data analysis shows that this ultrasonic cleaning approach results in a well-behaved ultrasonic cleaning/extraction behavior. That is, it does not show signs of accelerated cavitation erosion of the base material, which was later confirmed by neutron imaging. In addition, the analysis indicated that complete cleaning would be achieved by ultrasonic immersion cleaning at approximately 5 minutes, which was verified by subsequent cleaning of additional parts.

  10. BAAM Additive Manufacturing of Magnetically Levitated Wind Turbine

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Richardson, Bradley S.; Noakes, Mark W.; Roschli, Alex C.

    ORNL worked with Hover Energy LLC (Hover) on the design of Big Area Additive Manufacturing (BAAM) extrusion components. The objective of this technical collaboration was to identify and evaluate fabrication of components using alternative additive manufacturing techniques. Multiple candidate parts were identified. A design modification to fabricate diverters using additive manufacturing (AM) was performed and the part was analyzed based on anticipated wind loading. Scaled versions of two parts were printed using the BAAM for wind tunnel testing.

  11. Thermal analysis of laser additive manufacturing of aluminium alloys: Experiment and simulation

    NASA Astrophysics Data System (ADS)

    Bock, Frederic E.; Froend, Martin; Herrnring, Jan; Enz, Josephin; Kashaev, Nikolai; Klusemann, Benjamin

    2018-05-01

    Laser additive manufacturing (LAM) has become increasingly popular in industry in recent decades because it enables exceptional degrees of freedom regarding the structural design of lightweight components compared to subtractive manufacturing techniques. Laser metal deposition (LMD) of wire-fed material shows in particular the advantages such as high process velocity and efficient use of material compared to other LAM processes. During wire-based LMD, the material is deposited onto a substrate and supplemented by successive layers allowing a layer-wise production of complex three-dimensional structures. Despite the increased productivity of LMD, regarding the ability to process aluminium alloys, there is still a lack in quality and reproducibility due to the inhomogeneous temperature distribution during the process, leading to undesired residual stresses, distortions and inconsistent layer geometries and poor microstructures. In this study, the aluminium alloy AA5087 as wire and AA5754 as substrate material were utilized for LMD. In order to obtain information about the temperature field during LMD, thermocouple and thermography measurements were performed during the process. The temperature measurements were used to validate a finite element model regarding the heat distribution, which will be further used to investigate the temperature field evolution over time. To consider the continuous addition of material within the FE-model, an inactive/active element approach was chosen, where initially deactivated elements are activated corresponding to the deposition of material. The first results of the simulation and the experiments show good agreement. Therefore, the model can be used in the future for LMD process optimization, e.g., in terms of minimizing local variations of the thermal load for each layer.

  12. Spall fracture in additive manufactured Ti-6Al-4V

    DOE PAGES

    Jones, David Robert; Fensin, Saryu Jindal; Dippo, Olivia; ...

    2016-10-07

    Here, we present a study on the spall strength of additive manufactured (AM) Ti-6Al-4V. Samples were obtained from two pieces of selective laser melted (SLM, a powder bed fusion technique) Ti-6Al-4V such that the response to dynamic tensile loading could be investigated as a function of the orientation between the build layers and the loading direction. A sample of wrought bar-stock Ti-6Al-4V was also tested to act as a baseline representing the traditionally manufactured material response. A single-stage light gas-gun was used to launch a thin flyer plate into the samples, generating a region of intense tensile stress on amore » plane normal to the impact direction. The rear free surface velocity time history of each sample was recorded with laser-based velocimetry to allow the spall strength to be calculated. The samples were also soft recovered to enable post-mortem characterization of the spall damage evolution. Results showed that when the tensile load was applied normal to the interfaces between the build layers caused by the SLM fabrication process the spall strength was drastically reduced, dropping to 60% of that of the wrought material. However, when loaded parallel to the AM build layer interfaces the spall strength was found to remain at 95% of the wrought control, suggesting that when loading normal to the AM layer interfaces, void nucleation is facilitated more readily due to weaknesses along these boundaries. Quasi-static testing of the same sample orientations revealed a much lower degree of anisotropy, demonstrating the importance of rate-dependent studies for damage evolution in AM materials.« less

  13. Spall fracture in additive manufactured Ti-6Al-4V

    NASA Astrophysics Data System (ADS)

    Jones, D. R.; Fensin, S. J.; Dippo, O.; Beal, R. A.; Livescu, V.; Martinez, D. T.; Trujillo, C. P.; Florando, J. N.; Kumar, M.; Gray, G. T.

    2016-10-01

    We present a study on the spall strength of additive manufactured (AM) Ti-6Al-4V. Samples were obtained from two pieces of selective laser melted (SLM, a powder bed fusion technique) Ti-6Al-4V such that the response to dynamic tensile loading could be investigated as a function of the orientation between the build layers and the loading direction. A sample of wrought bar-stock Ti-6Al-4V was also tested to act as a baseline representing the traditionally manufactured material response. A single-stage light gas-gun was used to launch a thin flyer plate into the samples, generating a region of intense tensile stress on a plane normal to the impact direction. The rear free surface velocity time history of each sample was recorded with laser-based velocimetry to allow the spall strength to be calculated. The samples were also soft recovered to enable post-mortem characterization of the spall damage evolution. Results showed that when the tensile load was applied normal to the interfaces between the build layers caused by the SLM fabrication process the spall strength was drastically reduced, dropping to 60% of that of the wrought material. However, when loaded parallel to the AM build layer interfaces the spall strength was found to remain at 95% of the wrought control, suggesting that when loading normal to the AM layer interfaces, void nucleation is facilitated more readily due to weaknesses along these boundaries. Quasi-static testing of the same sample orientations revealed a much lower degree of anisotropy, demonstrating the importance of rate-dependent studies for damage evolution in AM materials.

  14. Preliminary Comparison of Properties between Ni-electroplated Stainless Steel Parts Fabricated with Laser Additive Manufacturing and Conventional Machining

    NASA Astrophysics Data System (ADS)

    Mäkinen, Mika; Jauhiainen, Eeva; Matilainen, Ville-Pekka; Riihimäki, Jaakko; Ritvanen, Jussi; Piili, Heidi; Salminen, Antti

    Laser additive manufacturing (LAM) is a fabrication technology, which enables production of complex parts from metallic materials with mechanical properties comparable to those of conventionally machined parts. These LAM parts are manufactured via melting metallic powder layer by layer with laser beam. Aim of this study is to define preliminarily the possibilities of using electroplating to supreme surface properties. Electrodeposited nickel and chromium as well as electroless (autocatalytic) deposited nickel was used to enhance laser additive manufactured and machined parts properties, like corrosion resistance, friction and wearing. All test pieces in this study were manufactured with a modified research AM equipment, equal to commercial EOS M series. The laser system used for tests was IPG 200 W CW fiber laser. The material used in this study for additive manufacturing was commercial stainless steel powder grade named SS316L. This SS316L is not equal to AISI 316L grade, but commercial name of this kind of powder is widely known in additive manufacturing as SS316L. Material used for fabrication of comparison test pieces (i.e. conventionally manufactured) was AISI 316L stainless steel bar. Electroplating was done in matrix cell and electroless was done in plastic sink properties of plated parts were tested within acetic acid salt spray corrosion chamber (AASS, SFS-EN-ISO 9227 standard). Adhesion of coating, friction and wearing properties were tested with Pin-On-Rod machine. Results show that in these preliminary tests, LAM parts and machined parts have certain differences due to manufacturing route and surface conditions. These have an effect on electroplated and electroless parts features on adhesion, corrosion, wearing and friction. However, further and more detailed studies are needed to fully understand these phenomena.

  15. Consolidation & Factors Influencing Sintering Process in Polymer Powder Based Additive Manufacturing

    NASA Astrophysics Data System (ADS)

    Sagar, M. B.; Elangovan, K.

    2017-08-01

    Additive Manufacturing (AM) is two decade old technology; where parts are build layer manufacturing method directly from a CAD template. Over the years, AM techniques changes the future way of part fabrication with enhanced intricacy and custom-made features are aimed. Commercially polymers, metals, ceramic and metal-polymer composites are in practice where polymers enhanced the expectations in AM and are considered as a kind of next industrial revolution. Growing trend in polymer application motivated to study their feasibility and properties. Laser sintering, Heat sintering and Inhibition sintering are the most successful AM techniques for polymers but having least application. The presentation gives up selective sintering of powder polymers and listed commercially available polymer materials. Important significant factors for effective processing and analytical approaches to access them are discussed.

  16. 40 CFR 79.20 - Application for registration by additive manufacturer.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... additive manufacturer. 79.20 Section 79.20 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) REGISTRATION OF FUELS AND FUEL ADDITIVES Additive Registration Procedures § 79.20 Application for registration by additive manufacturer. Any manufacturer of a designated...

  17. 40 CFR 79.20 - Application for registration by additive manufacturer.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... additive manufacturer. 79.20 Section 79.20 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) REGISTRATION OF FUELS AND FUEL ADDITIVES Additive Registration Procedures § 79.20 Application for registration by additive manufacturer. Any manufacturer of a designated...

  18. 40 CFR 79.20 - Application for registration by additive manufacturer.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... additive manufacturer. 79.20 Section 79.20 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) REGISTRATION OF FUELS AND FUEL ADDITIVES Additive Registration Procedures § 79.20 Application for registration by additive manufacturer. Any manufacturer of a designated...

  19. 40 CFR 79.20 - Application for registration by additive manufacturer.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... additive manufacturer. 79.20 Section 79.20 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) REGISTRATION OF FUELS AND FUEL ADDITIVES Additive Registration Procedures § 79.20 Application for registration by additive manufacturer. Any manufacturer of a designated...

  20. 40 CFR 79.20 - Application for registration by additive manufacturer.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... additive manufacturer. 79.20 Section 79.20 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) REGISTRATION OF FUELS AND FUEL ADDITIVES Additive Registration Procedures § 79.20 Application for registration by additive manufacturer. Any manufacturer of a designated...

  1. Additive manufacturing of hybrid circuits

    DOE PAGES

    Bell, Nelson S.; Sarobol, Pylin; Cook, Adam; ...

    2016-03-26

    There is a rising interest in developing functional electronics using additively manufactured components. Considerations in materials selection and pathways to forming hybrid circuits and devices must demonstrate useful electronic function; must enable integration; and must complement the complex shape, low cost, high volume, and high functionality of structural but generally electronically passive additively manufactured components. This article reviews several emerging technologies being used in industry and research/development to provide integration advantages of fabricating multilayer hybrid circuits or devices. First, we review a maskless, noncontact, direct write (DW) technology that excels in the deposition of metallic colloid inks for electrical interconnects.more » Second, we review a complementary technology, aerosol deposition (AD), which excels in the deposition of metallic and ceramic powder as consolidated, thick conformal coatings and is additionally patternable through masking. As a result, we show examples of hybrid circuits/devices integrated beyond 2-D planes, using combinations of DW or AD processes and conventional, established processes.« less

  2. Advanced Manufacturing Technologies (AMT): Additive Manufactured Hot Fire Planning and Testing in GRC Cell 32 Project

    NASA Technical Reports Server (NTRS)

    Fikes, John C.

    2014-01-01

    The objective of this project is to hot fire test an additively manufactured thrust chamber assembly TCA (injector and thrust chamber). GRC will install the additively manufactured Inconel 625 injector, two additively manufactured (SLM) water cooled Cu-Cr thrust chamber barrels and one additively manufactured (SLM) water cooled Cu-Cr thrust chamber nozzle on the test stand in Cell 32 and perform hot fire testing of the integrated TCA.

  3. Additive Manufacturing at LANL: Advanced Characterization to Explore the Science of a New Manufacturing Method

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Carpenter, John S.; Brown, Donald William; Clausen, Bjorn

    Additive manufacturing (AM), or three-dimensional (3D) printing as it is more commonly known, is defined as the process of joining materials and creating objects by melting, sintering, or fusing material in a layer-by-layer fashion coordinated via 3D model data.1 Subtractive, or traditional, manufacturing methodologies often consist of machining/removing material—like a sculptor—or forming material through the application of pressure—like a potter. Conversely, in an AM process, material is added in individual volume elements and built up in a way similar to interlocking building blocks, but with volume elements that are typically the size of a grain of sand. The additive processmore » often involves less waste when compared to subtractive techniques because material is only added when and where it is needed. Adjustments to the final structure are relatively straightforward and can be simply achieved by adjusting the 3D computer model. This makes the technology much more flexible than traditional, subtractive techniques where new tooling or forming equipment is usually needed to accommodate design changes. Also, the AM processes are beneficial because they permit the fabrication of unique geometries, such as miniaturized metal lattice structures, that cannot be achieved using traditional techniques. An example of a metal lattice structure is the Eiffel Tower with its Figure 1. Schematic showing required linkages between experimental and modeling thrusts in order to achieve science-based qualification. Arrows showing linkages are color-coded according to the funded projects listed. geometric, interconnecting struts that reduce the overall weight of the tower while maintaining strength. In AM, the size of the struts can be made smaller than the diameter of a human hair, which further reduces weight while maintaining strength—a combination of properties that can benefit many applications.« less

  4. Additive Manufacturing at LANL: Advanced Characterization to Explore the Science of a New Manufacturing Method

    DOE PAGES

    Carpenter, John S.; Brown, Donald William; Clausen, Bjorn; ...

    2017-03-01

    Additive manufacturing (AM), or three-dimensional (3D) printing as it is more commonly known, is defined as the process of joining materials and creating objects by melting, sintering, or fusing material in a layer-by-layer fashion coordinated via 3D model data.1 Subtractive, or traditional, manufacturing methodologies often consist of machining/removing material—like a sculptor—or forming material through the application of pressure—like a potter. Conversely, in an AM process, material is added in individual volume elements and built up in a way similar to interlocking building blocks, but with volume elements that are typically the size of a grain of sand. The additive processmore » often involves less waste when compared to subtractive techniques because material is only added when and where it is needed. Adjustments to the final structure are relatively straightforward and can be simply achieved by adjusting the 3D computer model. This makes the technology much more flexible than traditional, subtractive techniques where new tooling or forming equipment is usually needed to accommodate design changes. Also, the AM processes are beneficial because they permit the fabrication of unique geometries, such as miniaturized metal lattice structures, that cannot be achieved using traditional techniques. An example of a metal lattice structure is the Eiffel Tower with its Figure 1. Schematic showing required linkages between experimental and modeling thrusts in order to achieve science-based qualification. Arrows showing linkages are color-coded according to the funded projects listed. geometric, interconnecting struts that reduce the overall weight of the tower while maintaining strength. In AM, the size of the struts can be made smaller than the diameter of a human hair, which further reduces weight while maintaining strength—a combination of properties that can benefit many applications.« less

  5. Predictive modeling of solidification during laser additive manufacturing of nickel superalloys: recent developments, future directions

    NASA Astrophysics Data System (ADS)

    Ghosh, Supriyo

    2018-01-01

    Additive manufacturing (AM) processes produce parts with improved physical, chemical, and mechanical properties compared to conventional manufacturing processes. In AM processes, intricate part geometries are produced from multicomponent alloy powder, in a layer-by-layer fashion with multipass laser melting, solidification, and solid-state phase transformations, in a shorter manufacturing time, with minimal surface finishing, and at a reasonable cost. However, there is an increasing need for post-processing of the manufactured parts via, for example, stress relieving heat treatment and hot isostatic pressing to achieve homogeneous microstructure and properties at all times. Solidification in an AM process controls the size, shape, and distribution of the grains, the growth morphology, the elemental segregation and precipitation, the subsequent solid-state phase changes, and ultimately the material properties. The critical issues in this process are linked with multiphysics (such as fluid flow and diffusion of heat and mass) and multiscale (lengths, times and temperature ranges) challenges that arise due to localized rapid heating and cooling during AM processing. The alloy chemistry-process-microstructure-property-performance correlation in this process will be increasingly better understood through multiscale modeling and simulation.

  6. Improvements in Operational Readiness by Distributing Manufacturing Capability in the Supply Chain through Additive Manufacturing

    DTIC Science & Technology

    2017-12-01

    inefficiencies of a more complex system. Additional time may also be due to the longer distances traveled . The fulfillment time for a requisition to...Approved OMB No. 0704-0188 Public reporting burden for this collection of information is estimated to average 1 hour per response, including the time ...advanced manufacturing methods with additive manufacturing. This work decomposes the additive manufacturing processes into 11 primary functions. The time

  7. Systems and Methods for Fabricating Objects Including Amorphous Metal Using Techniques Akin to Additive Manufacturing

    NASA Technical Reports Server (NTRS)

    Hofmann, Douglas (Inventor)

    2017-01-01

    Systems and methods in accordance with embodiments of the invention fabricate objects including amorphous metals using techniques akin to additive manufacturing. In one embodiment, a method of fabricating an object that includes an amorphous metal includes: applying a first layer of molten metallic alloy to a surface; cooling the first layer of molten metallic alloy such that it solidifies and thereby forms a first layer including amorphous metal; subsequently applying at least one layer of molten metallic alloy onto a layer including amorphous metal; cooling each subsequently applied layer of molten metallic alloy such that it solidifies and thereby forms a layer including amorphous metal prior to the application of any adjacent layer of molten metallic alloy; where the aggregate of the solidified layers including amorphous metal forms a desired shape in the object to be fabricated; and removing at least the first layer including amorphous metal from the surface.

  8. Utility of Big Area Additive Manufacturing (BAAM) For The Rapid Manufacture of Customized Electric Vehicles

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Love, Lonnie J.

    This Oak Ridge National Laboratory (ORNL) Manufacturing Development Facility (MDF) technical collaboration project was conducted in two phases as a CRADA with Local Motors Inc. Phase 1 was previously reported as Advanced Manufacturing of Complex Cyber Mechanical Devices through Community Engagement and Micro-manufacturing and demonstrated the integration of components onto a prototype body part for a vehicle. Phase 2 was reported as Utility of Big Area Additive Manufacturing (BAAM) for the Rapid Manufacture of Customized Electric Vehicles and demonstrated the high profile live printing of an all-electric vehicle using ONRL s Big Area Additive Manufacturing (BAAM) technology. This demonstration generatedmore » considerable national attention and successfully demonstrated the capabilities of the BAAM system as developed by ORNL and Cincinnati, Inc. and the feasibility of additive manufacturing of a full scale electric vehicle as envisioned by the CRADA partner Local Motors, Inc.« less

  9. Sustainability issues in laser-based additive manufacturing

    NASA Astrophysics Data System (ADS)

    Sreenivasan, R.; Goel, A.; Bourell, D. L.

    Sustainability is a consideration of resource utilization without depletion or adverse environmental impact. In manufacturing, important sustainability issues include energy consumption, waste generation, water usage and the environmental impact of the manufactured part in service. This paper deals with three aspects of sustainability as it applies to additive manufacturing. First is a review of the research needs for energy and sustainability as applied to additive manufacturing based on the 2009 Roadmap for Additive Manufacturing Workshop. The second part is an energy assessment for selective laser sintering (SLS) of polymers. Using polyamide powder in a 3D Systems Vanguard HiQ Sinterstation, energy loss during a build was measured due to the chamber heaters, the roller mechanism, the piston elevators and the laser. This accounted for 95% of the total energy consumption. An overall energy assessment was accomplished using eco-indicators. The last topic is electrochemical deposition of porous SLS non-polymeric preforms. The goal is to reduce energy consumption in SLS of non-polymeric materials. The approach was to mix a transient binder with the material, to create an SLS green part, to convert the binder, and then to remove the open, connected porosity and to densify the part by chemical deposition at room temperature within the pore network. The model system was silicon carbide powder mixed with a phenolic transient binder coupled with electrolytic deposition of nickel. Deposition was facilitated by inserting a conductive graphite cathode in the part center to draw the positive nickel ions through the interconnected porous network and to deposit them on the pore walls. The Roadmap for Additive Manufacturing Workshop was sponsored by the National Science Foundation under Grant CMMI-0906212 and by the Office of Naval Research under Grant N00014-09-1-0558. The electrolytic deposition research was sponsored by the National Science Foundation, Grant CMMI-0926316.

  10. Additive Manufacturing for Affordable Rocket Engines

    NASA Technical Reports Server (NTRS)

    West, Brian; Robertson, Elizabeth; Osborne, Robin; Calvert, Marty

    2016-01-01

    Additive manufacturing (also known as 3D printing) technology has the potential to drastically reduce costs and lead times associated with the development of complex liquid rocket engine systems. NASA is using 3D printing to manufacture rocket engine components including augmented spark igniters, injectors, turbopumps, and valves. NASA is advancing the process to certify these components for flight. Success Story: MSFC has been developing rocket 3D-printing technology using the Selective Laser Melting (SLM) process. Over the last several years, NASA has built and tested several injectors and combustion chambers. Recently, MSFC has 3D printed an augmented spark igniter for potential use the RS-25 engines that will be used on the Space Launch System. The new design is expected to reduce the cost of the igniter by a factor of four. MSFC has also 3D printed and tested a liquid hydrogen turbopump for potential use on an Upper Stage Engine. Additive manufacturing of the turbopump resulted in a 45% part count reduction. To understanding how the 3D printed parts perform and to certify them for flight, MSFC built a breadboard liquid rocket engine using additive manufactured components including injectors, turbomachinery, and valves. The liquid rocket engine was tested seven times in 2016 using liquid oxygen and liquid hydrogen. In addition to exposing the hardware to harsh environments, engineers learned to design for the new manufacturing technique, taking advantage of its capabilities and gaining awareness of its limitations. Benefit: The 3D-printing technology promises reduced cost and schedule for rocket engines. Cost is a function of complexity, and the most complicated features provide the largest opportunities for cost reductions. This is especially true where brazes or welds can be eliminated. The drastic reduction in part count achievable with 3D printing creates a waterfall effect that reduces the number of processes and drawings, decreases the amount of touch

  11. Additive manufacturing of microfluidic glass chips

    NASA Astrophysics Data System (ADS)

    Kotz, F.; Helmer, D.; Rapp, B. E.

    2018-02-01

    Additive manufacturing has gained great interest in the microfluidic community due to the numerous channel designs which can be tested in the early phases of a lab-on-a-chip device development. High resolution additive manufacturing like microstereolithography is largely associated with polymers. Polymers are at a disadvantage compared to other materials due to their softness and low chemical resistance. Whenever high chemical and thermal resistance combined with high optical transparency is needed, glasses become the material of choice. However, glasses are difficult to structure at the microscale requiring hazardous chemicals for etching processes. In this work we present additive manufacturing and high resolution patterning of microfluidic chips in transparent fused silica glass using stereolithography and microlithography. We print an amorphous silica nanocomposite at room temperature using benchtop stereolithography printers and a custom built microlithography system based on a digital mirror device. Using microlithography we printed structures with tens of micron resolution. The printed part is then converted to a transparent fused silica glass using thermal debinding and sintering. Printing of a microfluidic chip can be done within 30 minutes. The heat treatment can be done within two days.

  12. Living Additive Manufacturing: Transformation of Parent Gels into Diversely Functionalized Daughter Gels Made Possible by Visible Light Photoredox Catalysis.

    PubMed

    Chen, Mao; Gu, Yuwei; Singh, Awaneesh; Zhong, Mingjiang; Jordan, Alex M; Biswas, Santidan; Korley, LaShanda T J; Balazs, Anna C; Johnson, Jeremiah A

    2017-02-22

    Light-initiated additive manufacturing techniques typically rely on layer-by-layer addition or continuous extraction of polymers formed via nonliving, free radical polymerization methods that render the final materials "dead" toward further monomer insertion; the polymer chains within the materials cannot be reactivated to induce chain extension. An alternative "living additive manufacturing" strategy would involve the use of photocontrolled living radical polymerization to spatiotemporally insert monomers into dormant "parent" materials to generate more complex and diversely functionalized "daughter" materials. Here, we demonstrate a proof-of-concept study of living additive manufacturing using end-linked polymer gels embedded with trithiocarbonate iniferters that can be activated by photoinduced single-electron transfer from an organic photoredox catalyst in solution. This system enables the synthesis of a wide range of chemically and mechanically differentiated daughter gels from a single type of parent gel via light-controlled modification of the parent's average composition, strand length, and/or cross-linking density. Daughter gels that are softer than their parent, stiffer than their parent, larger but with the same modulus as their parent, thermally responsive, polarity responsive, healable, and weldable are all realized.

  13. 2015 Summer Design Challenge: Team A&E (2241) Additively Manufactured Discriminator.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Miller, Sarah E.; Moore, Brandon James

    Current discriminator designs are based on historical designs and traditional manufacturing methods. The goal of this project was to form non-traditional groups to create novel discriminator designs by taking advantage of additive manufacturing. These designs would expand current discriminator designs and provide insight on the applicability of additive manufacturing for future projects. Our design stretched the current abilities of additive manufacturing and noted desired improvements for the future. Through collaboration with NSC, we noted several additional technologies which work well with additive manufacturing such as topology optimization and CT scanning and determined how these technologies could be improved to bettermore » combine with additive manufacturing.« less

  14. Characterization of Metal Powders Used for Additive Manufacturing.

    PubMed

    Slotwinski, J A; Garboczi, E J; Stutzman, P E; Ferraris, C F; Watson, S S; Peltz, M A

    2014-01-01

    Additive manufacturing (AM) techniques can produce complex, high-value metal parts, with potential applications as critical parts, such as those found in aerospace components. The production of AM parts with consistent and predictable properties requires input materials (e.g., metal powders) with known and repeatable characteristics, which in turn requires standardized measurement methods for powder properties. First, based on our previous work, we assess the applicability of current standardized methods for powder characterization for metal AM powders. Then we present the results of systematic studies carried out on two different powder materials used for additive manufacturing: stainless steel and cobalt-chrome. The characterization of these powders is important in NIST efforts to develop appropriate measurements and standards for additive materials and to document the property of powders used in a NIST-led additive manufacturing material round robin. An extensive array of characterization techniques was applied to these two powders, in both virgin and recycled states. The physical techniques included laser diffraction particle size analysis, X-ray computed tomography for size and shape analysis, and optical and scanning electron microscopy. Techniques sensitive to structure and chemistry, including X-ray diffraction, energy dispersive analytical X-ray analysis using the X-rays generated during scanning electron microscopy, and X-Ray photoelectron spectroscopy were also employed. The results of these analyses show how virgin powder changes after being exposed to and recycled from one or more Direct Metal Laser Sintering (DMLS) additive manufacturing build cycles. In addition, these findings can give insight into the actual additive manufacturing process.

  15. Characterization of Metal Powders Used for Additive Manufacturing

    PubMed Central

    Slotwinski, JA; Garboczi, EJ; Stutzman, PE; Ferraris, CF; Watson, SS; Peltz, MA

    2014-01-01

    Additive manufacturing (AM) techniques1 can produce complex, high-value metal parts, with potential applications as critical parts, such as those found in aerospace components. The production of AM parts with consistent and predictable properties requires input materials (e.g., metal powders) with known and repeatable characteristics, which in turn requires standardized measurement methods for powder properties. First, based on our previous work, we assess the applicability of current standardized methods for powder characterization for metal AM powders. Then we present the results of systematic studies carried out on two different powder materials used for additive manufacturing: stainless steel and cobalt-chrome. The characterization of these powders is important in NIST efforts to develop appropriate measurements and standards for additive materials and to document the property of powders used in a NIST-led additive manufacturing material round robin. An extensive array of characterization techniques was applied to these two powders, in both virgin and recycled states. The physical techniques included laser diffraction particle size analysis, X-ray computed tomography for size and shape analysis, and optical and scanning electron microscopy. Techniques sensitive to structure and chemistry, including X-ray diffraction, energy dispersive analytical X-ray analysis using the X-rays generated during scanning electron microscopy, and X-Ray photoelectron spectroscopy were also employed. The results of these analyses show how virgin powder changes after being exposed to and recycled from one or more Direct Metal Laser Sintering (DMLS) additive manufacturing build cycles. In addition, these findings can give insight into the actual additive manufacturing process. PMID:26601040

  16. Feasibility of using Big Area Additive Manufacturing to Directly Manufacture Boat Molds

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Post, Brian K.; Chesser, Phillip C.; Lind, Randall F.

    The goal of this project was to explore the feasibility of using Big Area Additive Manufacturing (BAAM) to directly manufacture a boat mold without the need for coatings. All prior tooling projects with BAAM required the use to thick coatings to overcome the surface finish limitations of the BAAM process. While the BAAM process significantly lowers the cost of building the mold, the high cost element rapidly became the coatings (cost of the material, labor on coating, and finishing). As an example, the time and cost to manufacture the molds for the Wind Turbine project with TPI Composites Inc. andmore » the molds for the submarine project with Carderock Naval Warfare Systems was a fraction of the time and cost of the coatings. For this project, a catamaran boat hull mold was designed, manufactured, and assembled with an additional 0.15” thickness of material on all mold surfaces. After printing, the mold was immediately machined and assembled. Alliance MG, LLC (AMG), the industry partner of this project, experimented with mold release agents on the carbon-fiber reinforced acrylonitrile butadiene styrene (CF ABS) to verify that the material can be directly used as a mold (rather than needing a coating). In addition, for large molds (such as the wind turbine mold with TPI Composites Inc.), the mold only provided the target surface. A steel subframe had to be manufactured to provide structural integrity. If successful, this will significantly reduce the time and cost necessary for manufacturing large resin infusion molds using the BAAM process.« less

  17. NASA OSMA NDE Program Additive Manufacturing Foundational Effort

    NASA Technical Reports Server (NTRS)

    Waller, Jess; Walker, James; Burke, Eric; Wells, Douglas

    2016-01-01

    NASA is providing key leadership in an international effort linking NASA and non-NASA resources to speed adoption of additive manufacturing (AM) to meet NASA's mission goals. Participants include industry, NASA's space partners, other government agencies, standards organizations and academia. Nondestructive Evaluation (NDE) is identified as a universal need for all aspects of additive manufacturing.

  18. Laser additive manufacturing bulk graphene-copper nanocomposites.

    PubMed

    Hu, Zengrong; Chen, Feng; Lin, Dong; Nian, Qiong; Parandoush, Pedram; Zhu, Xing; Shao, Zhuqiang; Cheng, Gary J

    2017-11-03

    The exceptional mechanical properties of graphene make it an ideal nanofiller for reinforcing metal matrix composites (MMCs). In this work, graphene-copper (Gr-Cu) nanocomposites have been fabricated by a laser additive manufacturing process. Transmission electron microscopy (TEM), x-ray diffraction (XRD) and Raman spectroscopy were utilized to characterize the fabricated nanocomposites. The XRD, Raman spectroscopy, energy dispersive spectroscopy and TEM results demonstrated the feasibility of laser additive manufacturing of Gr-Cu nanocomposites. The microstructures were characterized by high resolution TEM and the results further revealed the interface between the copper matrix and graphene. With the addition of graphene, the mechanical properties of the composites were enhanced significantly. Nanoindentation tests showed that the average modulus value and hardness of the composites were 118.9 GPa and 3 GPa respectively; 17.6% and 50% increases were achieved compared with pure copper, respectively. This work demonstrates a new way to manufacture graphene copper nanocomposites with ultra-strong mechanical properties and provides alternatives for applications in electrical and thermal conductors.

  19. Laser additive manufacturing bulk graphene-copper nanocomposites

    NASA Astrophysics Data System (ADS)

    Hu, Zengrong; Chen, Feng; Lin, Dong; Nian, Qiong; Parandoush, Pedram; Zhu, Xing; Shao, Zhuqiang; Cheng, Gary J.

    2017-11-01

    The exceptional mechanical properties of graphene make it an ideal nanofiller for reinforcing metal matrix composites (MMCs). In this work, graphene-copper (Gr-Cu) nanocomposites have been fabricated by a laser additive manufacturing process. Transmission electron microscopy (TEM), x-ray diffraction (XRD) and Raman spectroscopy were utilized to characterize the fabricated nanocomposites. The XRD, Raman spectroscopy, energy dispersive spectroscopy and TEM results demonstrated the feasibility of laser additive manufacturing of Gr-Cu nanocomposites. The microstructures were characterized by high resolution TEM and the results further revealed the interface between the copper matrix and graphene. With the addition of graphene, the mechanical properties of the composites were enhanced significantly. Nanoindentation tests showed that the average modulus value and hardness of the composites were 118.9 GPa and 3 GPa respectively; 17.6% and 50% increases were achieved compared with pure copper, respectively. This work demonstrates a new way to manufacture graphene copper nanocomposites with ultra-strong mechanical properties and provides alternatives for applications in electrical and thermal conductors.

  20. Sustainability Characterization for Additive Manufacturing

    PubMed Central

    Mani, Mahesh; Lyons, Kevin W; Gupta, SK

    2014-01-01

    Additive manufacturing (AM) has the potential to create geometrically complex parts that require a high degree of customization, using less material and producing less waste. Recent studies have shown that AM can be an economically viable option for use by the industry, yet there are some inherent challenges associated with AM for wider acceptance. The lack of standards in AM impedes its use for parts production since industries primarily depend on established standards in processes and material selection to ensure the consistency and quality. Inability to compare AM performance against traditional manufacturing methods can be a barrier for implementing AM processes. AM process sustainability has become a driver due to growing environmental concerns for manufacturing. This has reinforced the importance to understand and characterize AM processes for sustainability. Process characterization for sustainability will help close the gaps for comparing AM performance to traditional manufacturing methods. Based on a literature review, this paper first examines the potential environmental impacts of AM. A methodology for sustainability characterization of AM is then proposed to serve as a resource for the community to benchmark AM processes for sustainability. Next, research perspectives are discussed along with relevant standardization efforts. PMID:26601038

  1. Sustainability Characterization for Additive Manufacturing.

    PubMed

    Mani, Mahesh; Lyons, Kevin W; Gupta, S K

    2014-01-01

    Additive manufacturing (AM) has the potential to create geometrically complex parts that require a high degree of customization, using less material and producing less waste. Recent studies have shown that AM can be an economically viable option for use by the industry, yet there are some inherent challenges associated with AM for wider acceptance. The lack of standards in AM impedes its use for parts production since industries primarily depend on established standards in processes and material selection to ensure the consistency and quality. Inability to compare AM performance against traditional manufacturing methods can be a barrier for implementing AM processes. AM process sustainability has become a driver due to growing environmental concerns for manufacturing. This has reinforced the importance to understand and characterize AM processes for sustainability. Process characterization for sustainability will help close the gaps for comparing AM performance to traditional manufacturing methods. Based on a literature review, this paper first examines the potential environmental impacts of AM. A methodology for sustainability characterization of AM is then proposed to serve as a resource for the community to benchmark AM processes for sustainability. Next, research perspectives are discussed along with relevant standardization efforts.

  2. Additive Manufacturing Design Considerations for Liquid Engine Components

    NASA Technical Reports Server (NTRS)

    Whitten, Dave; Hissam, Andy; Baker, Kevin; Rice, Darron

    2014-01-01

    The Marshall Space Flight Center's Propulsion Systems Department has gained significant experience in the last year designing, building, and testing liquid engine components using additive manufacturing. The department has developed valve, duct, turbo-machinery, and combustion device components using this technology. Many valuable lessons were learned during this process. These lessons will be the focus of this presentation. We will present criteria for selecting part candidates for additive manufacturing. Some part characteristics are 'tailor made' for this process. Selecting the right parts for the process is the first step to maximizing productivity gains. We will also present specific lessons we learned about feature geometry that can and cannot be produced using additive manufacturing machines. Most liquid engine components were made using a two-step process. The base part was made using additive manufacturing and then traditional machining processes were used to produce the final part. The presentation will describe design accommodations needed to make the base part and lessons we learned about which features could be built directly and which require the final machine process. Tolerance capabilities, surface finish, and material thickness allowances will also be covered. Additive Manufacturing can produce internal passages that cannot be made using traditional approaches. It can also eliminate a significant amount of manpower by reducing part count and leveraging model-based design and analysis techniques. Information will be shared about performance enhancements and design efficiencies we experienced for certain categories of engine parts.

  3. Costs, Benefits, and Adoption of Additive Manufacturing: A Supply Chain Perspective.

    PubMed

    Thomas, Douglas

    2016-07-01

    There are three primary aspects to the economics of additive manufacturing: measuring the value of goods produced, measuring the costs and benefits of using the technology, and estimating the adoption and diffusion of the technology. This paper provides an updated estimate of the value of goods produced. It then reviews the literature on additive manufacturing costs and identifies those instances in the literature where this technology is cost effective. The paper then goes on to propose an approach for examining and understanding the societal costs and benefits of this technology both from a monetary viewpoint and a resource consumption viewpoint. The final section discusses the trends in the adoption of additive manufacturing. Globally, there is an estimated $667 million in value added produced using additive manufacturing, which equates to 0.01 % of total global manufacturing value added. US value added is estimated as $241 million. Current research on additive manufacturing costs reveals that it is cost effective for manufacturing small batches with continued centralized production; however, with increased automation distributed production may become cost effective. Due to the complexities of measuring additive manufacturing costs and data limitations, current studies are limited in their scope. Many of the current studies examine the production of single parts and those that examine assemblies tend not to examine supply chain effects such as inventory and transportation costs along with decreased risk to supply disruption. The additive manufacturing system and the material costs constitute a significant portion of an additive manufactured product; however, these costs are declining over time. The current trends in costs and benefits have resulted in this technology representing 0.02 % of the relevant manufacturing industries in the US; however, as the costs of additive manufacturing systems decrease, this technology may become widely adopted and change the

  4. Layer Additive Production or Manufacturing of Thick Sections of Ti-6Al-4V by Selective Electron Beam Melting (SEBM)

    NASA Astrophysics Data System (ADS)

    Sun, Y. Y.; Gulizia, S.; Fraser, D.; Oh, C. H.; Lu, S. L.; Qian, M.

    2017-10-01

    Selective electron beam melting (SEBM) is an established layer additive manufacturing or production process for small-to-medium-sized components of Ti-6Al-4V. Current literature data on SEBM of Ti-6Al-4V are, however, based principally on thin-section (<1″; mostly <0.5″) samples or components. In this research, 34-mm-thick (1.34″) Ti-6Al-4V block samples were produced through use of default Arcam SEBM parameters and characterized versus section thickness. High densities (99.4-99.8%) were achieved across different thick sections, but markedly inhomogeneous microstructures also developed. Nonetheless, the tensile properties measured from 27 different thickness-width positions all clearly satisfied the minimum requirements for mill-annealed Ti-6Al-4V. SEBM produced highly dense thick sections of Ti-6Al-4V with good tensile properties. Large lack-of-fusion defects (80-250 µm) were found to be mainly responsible for variations in tensile properties.

  5. Additive Manufacturing of Biomaterials, Tissues, and Organs.

    PubMed

    Zadpoor, Amir A; Malda, Jos

    2017-01-01

    The introduction of additive manufacturing (AM), often referred to as three-dimensional (3D) printing, has initiated what some believe to be a manufacturing revolution, and has expedited the development of the field of biofabrication. Moreover, recent advances in AM have facilitated further development of patient-specific healthcare solutions. Customization of many healthcare products and services, such as implants, drug delivery devices, medical instruments, prosthetics, and in vitro models, would have been extremely challenging-if not impossible-without AM technologies. The current special issue of the Annals of Biomedical Engineering presents the latest trends in application of AM techniques to healthcare-related areas of research. As a prelude to this special issue, we review here the most important areas of biomedical research and clinical practice that have benefited from recent developments in additive manufacturing techniques. This editorial, therefore, aims to sketch the research landscape within which the other contributions of the special issue can be better understood and positioned. In what follows, we briefly review the application of additive manufacturing techniques in studies addressing biomaterials, (re)generation of tissues and organs, disease models, drug delivery systems, implants, medical instruments, prosthetics, orthotics, and AM objects used for medical visualization and communication.

  6. A Modular Aerospike Engine Design Using Additive Manufacturing

    NASA Technical Reports Server (NTRS)

    Peugeot, John; Garcia, Chance; Burkhardt, Wendel

    2014-01-01

    A modular aerospike engine concept has been developed with the objective of demonstrating the viability of the aerospike design using additive manufacturing techniques. The aerospike system is a self-compensating design that allows for optimal performance over the entire flight regime and allows for the lowest possible mass vehicle designs. At low altitudes, improvements in Isp can be traded against chamber pressure, staging, and payload. In upper stage applications, expansion ratio and engine envelope can be traded against nozzle efficiency. These features provide flexibility to the System Designer optimizing a complete vehicle stage. The aerospike concept is a good example of a component that has demonstrated improved performance capability, but traditionally has manufacturing requirements that are too expensive and complex to use in a production vehicle. In recent years, additive manufacturing has emerged as a potential method for improving the speed and cost of building geometrically complex components in rocket engines. It offers a reduction in tooling overhead and significant improvements in the integration of the designer and manufacturing method. In addition, the modularity of the engine design provides the ability to perform full scale testing on the combustion devices outside of the full engine configuration. The proposed design uses a hydrocarbon based gas-generator cycle, with plans to take advantage of existing powerhead hardware while focusing DDT&E resources on manufacturing and sub-system testing of the combustion devices. The major risks for the modular aerospike concept lie in the performance of the propellant feed system, the structural integrity of the additive manufactured components, and the aerodynamic efficiency of the exhaust flow.

  7. The Crucial Role of Additive Manufacturing at NASA

    NASA Technical Reports Server (NTRS)

    Vickers, John

    2016-01-01

    At NASA, the first steps of the Journey to Mars are well underway with the development of NASA's next generation launch system and investments in research and technologies that should increase the affordability, capability, and safety of exploration activities. Additive Manufacturing presents a disruptive opportunity for NASA to design and manufacture hardware with new materials at dramatically reduced cost and schedule. Opportunities to incorporate additive manufacturing align very well with NASA missions and with most NASA programs related to space, science, and aeronautics. The Agency also relies on many partnerships with other government agencies, industry and academia.

  8. Computational Process Modeling for Additive Manufacturing

    NASA Technical Reports Server (NTRS)

    Bagg, Stacey; Zhang, Wei

    2014-01-01

    Computational Process and Material Modeling of Powder Bed additive manufacturing of IN 718. Optimize material build parameters with reduced time and cost through modeling. Increase understanding of build properties. Increase reliability of builds. Decrease time to adoption of process for critical hardware. Potential to decrease post-build heat treatments. Conduct single-track and coupon builds at various build parameters. Record build parameter information and QM Meltpool data. Refine Applied Optimization powder bed AM process model using data. Report thermal modeling results. Conduct metallography of build samples. Calibrate STK models using metallography findings. Run STK models using AO thermal profiles and report STK modeling results. Validate modeling with additional build. Photodiode Intensity measurements highly linear with power input. Melt Pool Intensity highly correlated to Melt Pool Size. Melt Pool size and intensity increase with power. Applied Optimization will use data to develop powder bed additive manufacturing process model.

  9. Additive Manufacturing of Composites and Complex Materials

    NASA Astrophysics Data System (ADS)

    Spowart, Jonathan E.; Gupta, Nikhil; Lehmhus, Dirk

    2018-03-01

    Advanced composite materials form an important class of high-performance industrial materials used in weight-sensitive applications such as aerospace structures, automotive structures and sports equipment. In many of these applications, parts are made in small production runs, are highly customized and involve long process development times. Developments in additive manufacturing (AM) methods have helped in overcoming many of these limitations. The special topic of Additive Manufacturing of Composites and Complex Materials captures the state of the art in this area by collecting nine papers that present much novel advancement in this field. The studies under this topic show advancement in the area of AM of carbon fiber and graphene-reinforced composites with high thermal and electrical conductivities, development of new hollow glass particle-filled syntactic foam filaments for printing lightweight structures and integration of sensors or actuators during AM of metallic parts. Some of the studies are focused on process optimization or modification to increase the manufacturing speed or tuning manufacturing techniques to enable AM of new materials.

  10. An Analysis Of Additive Manufacturing Production Problems And Solutions

    DTIC Science & Technology

    2016-12-01

    democratization of manufacturing (Hornick, 2015). AM has three distinct advantages over subtractive manufacturing : product customization, design flexibility...58 develops software and other technology solutions for the design , analysis, testing, manufacture , and validation of products (Diane Ryan, personal...NAVAL POSTGRADUATE SCHOOL MONTEREY, CALIFORNIA MBA PROFESSIONAL REPORT AN ANALYSIS OF ADDITIVE MANUFACTURING PRODUCTION

  11. Costs, Benefits, and Adoption of Additive Manufacturing: A Supply Chain Perspective

    PubMed Central

    Thomas, Douglas

    2017-01-01

    There are three primary aspects to the economics of additive manufacturing: measuring the value of goods produced, measuring the costs and benefits of using the technology, and estimating the adoption and diffusion of the technology. This paper provides an updated estimate of the value of goods produced. It then reviews the literature on additive manufacturing costs and identifies those instances in the literature where this technology is cost effective. The paper then goes on to propose an approach for examining and understanding the societal costs and benefits of this technology both from a monetary viewpoint and a resource consumption viewpoint. The final section discusses the trends in the adoption of additive manufacturing. Globally, there is an estimated $667 million in value added produced using additive manufacturing, which equates to 0.01 % of total global manufacturing value added. US value added is estimated as $241 million. Current research on additive manufacturing costs reveals that it is cost effective for manufacturing small batches with continued centralized production; however, with increased automation distributed production may become cost effective. Due to the complexities of measuring additive manufacturing costs and data limitations, current studies are limited in their scope. Many of the current studies examine the production of single parts and those that examine assemblies tend not to examine supply chain effects such as inventory and transportation costs along with decreased risk to supply disruption. The additive manufacturing system and the material costs constitute a significant portion of an additive manufactured product; however, these costs are declining over time. The current trends in costs and benefits have resulted in this technology representing 0.02 % of the relevant manufacturing industries in the US; however, as the costs of additive manufacturing systems decrease, this technology may become widely adopted and change the

  12. Considerations on the construction of a Powder Bed Fusion platform for Additive Manufacturing

    NASA Astrophysics Data System (ADS)

    Andersen, Sebastian Aagaard; Nielsen, Karl-Emil; Pedersen, David Bue; Nielsen, Jakob Skov

    As the demand for moulds and other tools becomes increasingly specific and complex, an additive manufacturing approach to production is making its way to the industry through laser based consolidation of metal powder particles by a method known as powder bed fusion. This paper concerns a variety of design choices facilitating the development of an experimental powder bed fusion machine tool, capable of manufacturing metal parts with strength matching that of conventional manufactured parts and a complexity surpassing that of subtractive processes. To understand the different mechanisms acting within such an experimental machine tool, a fully open and customizable rig is constructed. Emphasizing modularity in the rig, allows alternation of lasers, scanner systems, optical elements, powder deposition, layer height, temperature, atmosphere, and powder type. Through a custom-made software platform, control of the process is achieved, which extends into a graphical user interface, easing adjustment of process parameters and the job file generation.

  13. Robot-based additive manufacturing for flexible die-modelling in incremental sheet forming

    NASA Astrophysics Data System (ADS)

    Rieger, Michael; Störkle, Denis Daniel; Thyssen, Lars; Kuhlenkötter, Bernd

    2017-10-01

    The paper describes the application concept of additive manufactured dies to support the robot-based incremental sheet metal forming process (`Roboforming') for the production of sheet metal components in small batch sizes. Compared to the dieless kinematic-based generation of a shape by means of two cooperating industrial robots, the supporting robot models a die on the back of the metal sheet by using the robot-based fused layer manufacturing process (FLM). This tool chain is software-defined and preserves the high geometrical form flexibility of Roboforming while flexibly generating support structures adapted to the final part's geometry. Test series serve to confirm the feasibility of the concept by investigating the process challenges of the adhesion to the sheet surface and the general stability as well as the influence on the geometric accuracy compared to the well-known forming strategies.

  14. Overview of Additive Manufacturing Initiatives at NASA Marshall Space Flight Center

    NASA Technical Reports Server (NTRS)

    Clinton, R. G., Jr.

    2018-01-01

    NASA's In Space Manufacturing Initiative (ISM) includes: The case for ISM - why; ISM path to exploration - results from the 3D Printing In Zero-G Technology Demonstration - ISM challenges; In space Robotic Manufacturing and Assembly (IRMA); Additive construction. Additively Manufacturing (AM) development for liquid rocket engine space flight hardware. MSFC standard and specification for additively manufactured space flight hardware. Summary.

  15. Additive manufacturing of reflective optics: evaluating finishing methods

    NASA Astrophysics Data System (ADS)

    Leuteritz, G.; Lachmayer, R.

    2018-02-01

    Individually shaped light distributions become more and more important in lighting technologies and thus the importance of additively manufactured reflectors increases significantly. The vast field of applications ranges from automotive lighting to medical imaging and bolsters the statement. However, the surfaces of additively manufactured reflectors suffer from insufficient optical properties even when manufactured using optimized process parameters for the Selective Laser Melting (SLM) process. Therefore post-process treatments of reflectors are necessary in order to further enhance their optical quality. This work concentrates on the effectiveness of post-process procedures for reflective optics. Based on already optimized aluminum reflectors, which are manufactured with a SLM machine, the parts are differently machined after the SLM process. Selected finishing methods like laser polishing, sputtering or sand blasting are applied and their effects quantified and compared. The post-process procedures are investigated on their impact on surface roughness and reflectance as well as geometrical precision. For each finishing method a demonstrator will be created and compared to a fully milled sample and among themselves. Ultimately, guidelines are developed in order to figure out the optimal treatment of additively manufactured reflectors regarding their optical and geometrical properties. Simulations of the light distributions will be validated with the developed demonstrators.

  16. Infrared preheating to improve interlayer strength of big area additive manufacturing (BAAM) components

    DOE PAGES

    Kishore, Vidya; Ajinjeru, Christine; Nycz, Andrzej; ...

    2017-03-01

    The Big Area Additive Manufacturing (BAAM) system can print structures on the order of several meters at high extrusion rates, thereby having the potential to significantly impact automotive, aerospace and energy sectors. The functional use of such parts, however, may be limited by mechanical anisotropy in which the strength of printed parts across successive layers in the build direction (z-direction) is significantly lower than the corresponding in-plane strength (x-y directions). This has been primarily attributed to poor bonding between printed layers as the lower layers cool below the glass transition temperature (Tg) before the next layer is deposited. Therefore, themore » potential of using infrared heating is considered for increasing the surface temperature of the printed layer just prior to deposition of new material to improve the interlayer strength of the components. This study found significant improvements in bond strength for the deposition of acrylonitrile butadiene styrene (ABS) reinforced with 20% chopped carbon fiber when the surface temperature of the substrate material was increased from below Tg to close to or above Tg using infrared heating.« less

  17. Infrared preheating to improve interlayer strength of big area additive manufacturing (BAAM) components

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kishore, Vidya; Ajinjeru, Christine; Nycz, Andrzej

    The Big Area Additive Manufacturing (BAAM) system can print structures on the order of several meters at high extrusion rates, thereby having the potential to significantly impact automotive, aerospace and energy sectors. The functional use of such parts, however, may be limited by mechanical anisotropy in which the strength of printed parts across successive layers in the build direction (z-direction) is significantly lower than the corresponding in-plane strength (x-y directions). This has been primarily attributed to poor bonding between printed layers as the lower layers cool below the glass transition temperature (Tg) before the next layer is deposited. Therefore, themore » potential of using infrared heating is considered for increasing the surface temperature of the printed layer just prior to deposition of new material to improve the interlayer strength of the components. This study found significant improvements in bond strength for the deposition of acrylonitrile butadiene styrene (ABS) reinforced with 20% chopped carbon fiber when the surface temperature of the substrate material was increased from below Tg to close to or above Tg using infrared heating.« less

  18. Nano-Magnets and Additive Manufacturing for Electric Motors

    NASA Technical Reports Server (NTRS)

    Misra, Ajay K.

    2014-01-01

    High power density is required for application of electric motors in hybrid electric propulsion. Potential path to achieve high power density in electric motors include advanced materials, lightweight thermal management, lightweight structural concepts, high power density power electronics, and advanced manufacturing. This presentation will focus on two key technologies for achieving high power density, advanced magnets and additive manufacturing. The maximum energy product in current magnets is reaching their theoretical limits as a result of material and process improvements. Future improvements in the maximum energy product for magnets can be achieved through development of nanocomposite magnets combining the hard magnetic phase and soft magnetic phase at the nanoscale level. The presentation will provide an overview of the current state of development for nanocomposite magnets and the future path for doubling the maximum energy product. The other part of the presentation will focus on the role of additive manufacturing in fabrication of high power density electric motors. The presentation will highlight the potential opportunities for applying additive manufacturing to fabricate electric motors.

  19. Additively Manufactured Low Cost Upper Stage Combustion Chamber

    NASA Technical Reports Server (NTRS)

    Protz, Christopher; Cooper, Ken; Ellis, David; Fikes, John; Jones, Zachary; Kim, Tony; Medina, Cory; Taminger, Karen; Willingham, Derek

    2016-01-01

    Over the past two years NASA's Low Cost Upper Stage Propulsion (LCUSP) project has developed Additive Manufacturing (AM) technologies and design tools aimed at reducing the costs and manufacturing time of regeneratively cooled rocket engine components. High pressure/high temperature combustion chambers and nozzles must be regeneratively cooled to survive their operating environment, causing their design fabrication to be costly and time consuming due to the number of individual steps and different processes required. Under LCUSP, AM technologies in Sintered Laser Melting (SLM) GRCop-84 and Electron Beam Freeform Fabrication (EBF3) Inconel 625 have been significantly advanced, allowing the team to successfully fabricate a 25k-class regenerative chamber. Estimates of the costs and schedule of future builds indicate cost reductions and significant schedule reductions will be enabled by this technology. Characterization of the microstructural and mechanical properties of the SLM-produced GRCop-84, EBF3 Inconel 625 and the interface layer between the two has been performed and indicates the properties will meet the design requirements. The LCUSP chamber is to be tested with a previously demonstrated SLM injector in order to advance the Technology Readiness Level (TRL) and demonstrate the capability of the application of these processes. NASA is advancing these technologies to reduce cost and schedule for future engine applications and commercial needs.

  20. Fabrication of Turbine Disk Materials by Additive Manufacturing

    NASA Technical Reports Server (NTRS)

    Sudbrack, Chantal; Bean, Quincy A.; Cooper, Ken; Carter, Robert; Semiatin, S. Lee; Gabb, Tim

    2014-01-01

    Precipitation-strengthened, nickel-based superalloys are widely used in the aerospace and energy industries due to their excellent environmental resistance and outstanding mechanical properties under extreme conditions. Powder-bed additive manufacturing (AM) technologies offer the potential to revolutionize the processing of superalloy turbine components by eliminating the need for extensive inventory or expensive legacy tooling. Like selective laser melting (SLM), electron beam melting (EBM) constructs three-dimensional dense components layer-by-layer by melting and solidification of atomized, pre-alloyed powder feedstock within 50-200 micron layers. While SLM has been more widely used for AM of nickel alloys like 718, EBM offers several distinct advantages, such as less retained residual stress, lower risk of contamination, and faster build rates with multiple-electron-beam configurations. These advantages are particularly attractive for turbine disks, for which excessive residual stress and contamination can shorten disk life during high-temperature operation. In this presentation, we will discuss the feasibility of fabricating disk superalloy components using EBM AM. Originally developed using powder metallurgy forging processing, disk superalloys contain a higher refractory content and precipitate volume fraction than alloy 718, thus making them more prone to thermal cracking during AM. This and other challenges to produce homogeneous builds with desired properties will be presented. In particular, the quality of lab-scale samples fabricated via a design of experiments, in which the beam current, build temperature, and beam velocity were varied, will be summarized. The relationship between processing parameters, microstructure, grain orientation, and mechanical response will be discussed.

  1. Integrating Fiber Optic Strain Sensors into Metal Using Ultrasonic Additive Manufacturing

    NASA Astrophysics Data System (ADS)

    Hehr, Adam; Norfolk, Mark; Wenning, Justin; Sheridan, John; Leser, Paul; Leser, Patrick; Newman, John A.

    2018-03-01

    Ultrasonic additive manufacturing, a rather new three-dimensional (3D) printing technology, uses ultrasonic energy to produce metallurgical bonds between layers of metal foils near room temperature. This low temperature attribute of the process enables integration of temperature sensitive components, such as fiber optic strain sensors, directly into metal structures. This may be an enabling technology for Digital Twin applications, i.e., virtual model interaction and feedback with live load data. This study evaluates the consolidation quality, interface robustness, and load sensing limits of commercially available fiber optic strain sensors embedded into aluminum alloy 6061. Lastly, an outlook on the technology and its applications is described.

  2. Applications of Metal Additive Manufacturing in Veterinary Orthopedic Surgery

    NASA Astrophysics Data System (ADS)

    Harrysson, Ola L. A.; Marcellin-Little, Denis J.; Horn, Timothy J.

    2015-03-01

    Veterinary medicine has undergone a rapid increase in specialization over the last three decades. Veterinarians now routinely perform joint replacement, neurosurgery, limb-sparing surgery, interventional radiology, radiation therapy, and other complex medical procedures. Many procedures involve advanced imaging and surgical planning. Evidence-based medicine has also become part of the modus operandi of veterinary clinicians. Modeling and additive manufacturing can provide individualized or customized therapeutic solutions to support the management of companion animals with complex medical problems. The use of metal additive manufacturing is increasing in veterinary orthopedic surgery. This review describes and discusses current and potential applications of metal additive manufacturing in veterinary orthopedic surgery.

  3. Post Processing Methods used to Improve Surface Finish of Products which are Manufactured by Additive Manufacturing Technologies: A Review

    NASA Astrophysics Data System (ADS)

    Kumbhar, N. N.; Mulay, A. V.

    2016-08-01

    The Additive Manufacturing (AM) processes open the possibility to go directly from Computer-Aided Design (CAD) to a physical prototype. These prototypes are used as test models before it is finalized as well as sometimes as a final product. Additive Manufacturing has many advantages over the traditional process used to develop a product such as allowing early customer involvement in product development, complex shape generation and also save time as well as money. Additive manufacturing also possess some special challenges that are usually worth overcoming such as Poor Surface quality, Physical Properties and use of specific raw material for manufacturing. To improve the surface quality several attempts had been made by controlling various process parameters of Additive manufacturing and also applying different post processing techniques on components manufactured by Additive manufacturing. The main objective of this work is to document an extensive literature review in the general area of post processing techniques which are used in Additive manufacturing.

  4. Anomaly Detection In Additively Manufactured Parts Using Laser Doppler Vibrometery

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hernandez, Carlos A.

    Additively manufactured parts are susceptible to non-uniform structure caused by the unique manufacturing process. This can lead to structural weakness or catastrophic failure. Using laser Doppler vibrometry and frequency response analysis, non-contact detection of anomalies in additively manufactured parts may be possible. Preliminary tests show promise for small scale detection, but more future work is necessary.

  5. Thermographic In-Situ Process Monitoring of the Electron Beam Melting Technology used in Additive Manufacturing

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dinwiddie, Ralph Barton; Dehoff, Ryan R; Lloyd, Peter D

    2013-01-01

    Oak Ridge National Laboratory (ORNL) has been utilizing the ARCAM electron beam melting technology to additively manufacture complex geometric structures directly from powder. Although the technology has demonstrated the ability to decrease costs, decrease manufacturing lead-time and fabricate complex structures that are impossible to fabricate through conventional processing techniques, certification of the component quality can be challenging. Because the process involves the continuous deposition of successive layers of material, each layer can be examined without destructively testing the component. However, in-situ process monitoring is difficult due to metallization on inside surfaces caused by evaporation and condensation of metal from themore » melt pool. This work describes a solution to one of the challenges to continuously imaging inside of the chamber during the EBM process. Here, the utilization of a continuously moving Mylar film canister is described. Results will be presented related to in-situ process monitoring and how this technique results in improved mechanical properties and reliability of the process.« less

  6. Friction Stir Additive Manufacturing: Route to High Structural Performance

    NASA Astrophysics Data System (ADS)

    Palanivel, S.; Sidhar, H.; Mishra, R. S.

    2015-03-01

    Aerospace and automotive industries provide the next big opportunities for additive manufacturing. Currently, the additive industry is confronted with four major challenges that have been identified in this article. These challenges need to be addressed for the additive technologies to march into new frontiers and create additional markets. Specific potential success in the transportation sectors is dependent on the ability to manufacture complicated structures with high performance. Most of the techniques used for metal-based additive manufacturing are fusion based because of their ability to fulfill the computer-aided design to component vision. Although these techniques aid in fabrication of complex shapes, achieving high structural performance is a key problem due to the liquid-solid phase transformation. In this article, friction stir additive manufacturing (FSAM) is shown as a potential solid-state process for attaining high-performance lightweight alloys for simpler geometrical applications. To illustrate FSAM as a high-performance route, manufactured builds of Mg-4Y-3Nd and AA5083 are shown as examples. In the Mg-based alloy, an average hardness of 120 HV was achieved in the built structure and was significantly higher than that of the base material (97 HV). Similarly for the Al-based alloy, compared with the base hardness of 88 HV, the average built hardness was 104 HV. A potential application of FSAM is illustrated by taking an example of a simple stiffener assembly.

  7. Mechanical Properties of a Newly Additive Manufactured Implant Material Based on Ti-42Nb

    PubMed Central

    Schulze, Christian; Weinmann, Markus; Schweigel, Christoph; Keßler, Olaf; Bader, Rainer

    2018-01-01

    The application of Ti-6Al-4V alloy or commercially pure titanium for additive manufacturing enables the fabrication of complex structural implants and patient-specific implant geometries. However, the difference in Young’s modulus of α + β-phase Ti alloys compared to the human bone promotes stress-shielding effects in the implant–bone interphase. The aim of the present study is the mechanical characterization of a new pre-alloyed β-phase Ti-42Nb alloy for application in additive manufacturing. The present investigation focuses on the mechanical properties of SLM-printed Ti-42Nb alloy in tensile and compression tests. In addition, the raw Ti-42Nb powder, the microstructure of the specimens prior to and after compression tests, as well as the fracture occurring in tensile tests are characterized by means of the SEM/EDX analysis. The Ti-42Nb raw powder exhibits a dendrite-like Ti-structure, which is melted layer-by-layer into a microstructure with a very homogeneous distribution of Nb and Ti during the SLM process. Tensile tests display Young’s modulus of 60.51 ± 3.92 GPa and an ultimate tensile strength of 683.17 ± 16.67 MPa, whereas, under a compressive load, a compressive strength of 1330.74 ± 53.45 MPa is observed. The combination of high mechanical strength and low elastic modulus makes Ti-42Nb an interesting material for orthopedic and dental implants. The spherical shape of the pre-alloyed material additionally allows for application in metal 3D printing, enabling the fabrication of patient-specific structural implants. PMID:29342864

  8. Mechanical Properties of a Newly Additive Manufactured Implant Material Based on Ti-42Nb.

    PubMed

    Schulze, Christian; Weinmann, Markus; Schweigel, Christoph; Keßler, Olaf; Bader, Rainer

    2018-01-13

    The application of Ti-6Al-4V alloy or commercially pure titanium for additive manufacturing enables the fabrication of complex structural implants and patient-specific implant geometries. However, the difference in Young's modulus of α + β-phase Ti alloys compared to the human bone promotes stress-shielding effects in the implant-bone interphase. The aim of the present study is the mechanical characterization of a new pre-alloyed β-phase Ti-42Nb alloy for application in additive manufacturing. The present investigation focuses on the mechanical properties of SLM-printed Ti-42Nb alloy in tensile and compression tests. In addition, the raw Ti-42Nb powder, the microstructure of the specimens prior to and after compression tests, as well as the fracture occurring in tensile tests are characterized by means of the SEM/EDX analysis. The Ti-42Nb raw powder exhibits a dendrite-like Ti-structure, which is melted layer-by-layer into a microstructure with a very homogeneous distribution of Nb and Ti during the SLM process. Tensile tests display Young's modulus of 60.51 ± 3.92 GPa and an ultimate tensile strength of 683.17 ± 16.67 MPa, whereas, under a compressive load, a compressive strength of 1330.74 ± 53.45 MPa is observed. The combination of high mechanical strength and low elastic modulus makes Ti-42Nb an interesting material for orthopedic and dental implants. The spherical shape of the pre-alloyed material additionally allows for application in metal 3D printing, enabling the fabrication of patient-specific structural implants.

  9. Research on Mechanisms and Controlling Methods of Macro Defects in TC4 Alloy Fabricated by Wire Additive Manufacturing.

    PubMed

    Ji, Lei; Lu, Jiping; Tang, Shuiyuan; Wu, Qianru; Wang, Jiachen; Ma, Shuyuan; Fan, Hongli; Liu, Changmeng

    2018-06-28

    Wire feeding additive manufacturing (WFAM) has broad application prospects because of its advantages of low cost and high efficiency. However, with the mode of lateral wire feeding, including wire and laser additive manufacturing, gas tungsten arc additive manufacturing etc., it is easy to generate macro defects on the surface of the components because of the anisotropy of melted wire, which limits the promotion and application of WFAM. In this work, gas tungsten arc additive manufacturing with lateral wire feeding is proposed to investigate the mechanisms of macro defects. The results illustrate that the defect forms mainly include side spatters, collapse, poor flatness, and unmelted wire. It was found that the heat input, layer thickness, tool path, and wire curvature can have an impact on the macro defects. Side spatters are the most serious defects, mainly because the droplets cannot be transferred to the center of the molten pool in the lateral wire feeding mode. This research indicates that the macro defects can be controlled by optimizing the process parameters. Finally, block parts without macro defects were fabricated, which is meaningful for the further application of WFAM.

  10. Workshop Report on Additive Manufacturing for Large-Scale Metal Components - Development and Deployment of Metal Big-Area-Additive-Manufacturing (Large-Scale Metals AM) System

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Babu, Sudarsanam Suresh; Love, Lonnie J.; Peter, William H.

    Additive manufacturing (AM) is considered an emerging technology that is expected to transform the way industry can make low-volume, high value complex structures. This disruptive technology promises to replace legacy manufacturing methods for the fabrication of existing components in addition to bringing new innovation for new components with increased functional and mechanical properties. This report outlines the outcome of a workshop on large-scale metal additive manufacturing held at Oak Ridge National Laboratory (ORNL) on March 11, 2016. The charter for the workshop was outlined by the Department of Energy (DOE) Advanced Manufacturing Office program manager. The status and impact ofmore » the Big Area Additive Manufacturing (BAAM) for polymer matrix composites was presented as the background motivation for the workshop. Following, the extension of underlying technology to low-cost metals was proposed with the following goals: (i) High deposition rates (approaching 100 lbs/h); (ii) Low cost (<$10/lbs) for steel, iron, aluminum, nickel, as well as, higher cost titanium, (iii) large components (major axis greater than 6 ft) and (iv) compliance of property requirements. The above concept was discussed in depth by representatives from different industrial sectors including welding, metal fabrication machinery, energy, construction, aerospace and heavy manufacturing. In addition, DOE’s newly launched High Performance Computing for Manufacturing (HPC4MFG) program was reviewed. This program will apply thermo-mechanical models to elucidate deeper understanding of the interactions between design, process, and materials during additive manufacturing. Following these presentations, all the attendees took part in a brainstorming session where everyone identified the top 10 challenges in large-scale metal AM from their own perspective. The feedback was analyzed and grouped in different categories including, (i) CAD to PART software, (ii) selection of energy source, (iii

  11. Additive manufacturing technology in reconstructive surgery.

    PubMed

    Fuller, Scott C; Moore, Michael G

    2016-10-01

    Technological advances have been part and parcel of modern reconstructive surgery, in that practitioners of this discipline are continually looking for innovative ways to perfect their craft and improve patient outcomes. We are currently in a technological climate wherein advances in computers, imaging, and science have coalesced with resulting innovative breakthroughs that are not merely limited to improved outcomes and enhanced patient care, but may provide novel approaches to training the next generation of reconstructive surgeons. New developments in software and modeling platforms, imaging modalities, tissue engineering, additive manufacturing, and customization of implants are poised to revolutionize the field of reconstructive surgery. The interface between technological advances and reconstructive surgery continues to expand. Additive manufacturing techniques continue to evolve in an effort to improve patient outcomes, decrease operative time, and serve as instructional tools for the training of reconstructive surgeons.

  12. A Fully Non-Metallic Gas Turbine Engine Enabled by Additive Manufacturing Part I: System Analysis, Component Identification, Additive Manufacturing, and Testing of Polymer Composites

    NASA Technical Reports Server (NTRS)

    Grady, Joseph E.; Haller, William J.; Poinsatte, Philip E.; Halbig, Michael C.; Schnulo, Sydney L.; Singh, Mrityunjay; Weir, Don; Wali, Natalie; Vinup, Michael; Jones, Michael G.; hide

    2015-01-01

    The research and development activities reported in this publication were carried out under NASA Aeronautics Research Institute (NARI) funded project entitled "A Fully Nonmetallic Gas Turbine Engine Enabled by Additive Manufacturing." The objective of the project was to conduct evaluation of emerging materials and manufacturing technologies that will enable fully nonmetallic gas turbine engines. The results of the activities are described in three part report. The first part of the report contains the data and analysis of engine system trade studies, which were carried out to estimate reduction in engine emissions and fuel burn enabled due to advanced materials and manufacturing processes. A number of key engine components were identified in which advanced materials and additive manufacturing processes would provide the most significant benefits to engine operation. The technical scope of activities included an assessment of the feasibility of using additive manufacturing technologies to fabricate gas turbine engine components from polymer and ceramic matrix composites, which were accomplished by fabricating prototype engine components and testing them in simulated engine operating conditions. The manufacturing process parameters were developed and optimized for polymer and ceramic composites (described in detail in the second and third part of the report). A number of prototype components (inlet guide vane (IGV), acoustic liners, engine access door) were additively manufactured using high temperature polymer materials. Ceramic matrix composite components included turbine nozzle components. In addition, IGVs and acoustic liners were tested in simulated engine conditions in test rigs. The test results are reported and discussed in detail.

  13. Metal Additive Manufacturing: A Review of Mechanical Properties

    NASA Astrophysics Data System (ADS)

    Lewandowski, John J.; Seifi, Mohsen

    2016-07-01

    This article reviews published data on the mechanical properties of additively manufactured metallic materials. The additive manufacturing techniques utilized to generate samples covered in this review include powder bed fusion (e.g., EBM, SLM, DMLS) and directed energy deposition (e.g., LENS, EBF3). Although only a limited number of metallic alloy systems are currently available for additive manufacturing (e.g., Ti-6Al-4V, TiAl, stainless steel, Inconel 625/718, and Al-Si-10Mg), the bulk of the published mechanical properties information has been generated on Ti-6Al-4V. However, summary tables for published mechanical properties and/or key figures are included for each of the alloys listed above, grouped by the additive technique used to generate the data. Published values for mechanical properties obtained from hardness, tension/compression, fracture toughness, fatigue crack growth, and high cycle fatigue are included for as-built, heat-treated, and/or HIP conditions, when available. The effects of test orientation/build direction on properties, when available, are also provided, along with discussion of the potential source(s) (e.g., texture, microstructure changes, defects) of anisotropy in properties. Recommendations for additional work are also provided.

  14. Energetic additive manufacturing process with feed wire

    DOEpatents

    Harwell, Lane D.; Griffith, Michelle L.; Greene, Donald L.; Pressly, Gary A.

    2000-11-07

    A process for additive manufacture by energetic wire deposition is described. A source wire is fed into a energy beam generated melt-pool on a growth surface as the melt-pool moves over the growth surface. This process enables the rapid prototyping and manufacture of fully dense, near-net shape components, as well as cladding and welding processes. Alloys, graded materials, and other inhomogeneous materials can be grown using this process.

  15. A Fully Non-Metallic Gas Turbine Engine Enabled by Additive Manufacturing

    NASA Technical Reports Server (NTRS)

    Grady, Joseph E.; Halbig, Michael C.; Singh, Mrityunjay

    2015-01-01

    In a NASA Aeronautics Research Institute (NARI) sponsored program entitled "A Fully Non-Metallic Gas Turbine Engine Enabled by Additive Manufacturing," evaluation of emerging materials and additive manufacturing technologies was carried out. These technologies may enable fully non-metallic gas turbine engines in the future. This paper highlights the results of engine system trade studies which were carried out to estimate reduction in engine emissions and fuel burn enabled due to advanced materials and manufacturing processes. A number of key engine components were identified in which advanced materials and additive manufacturing processes would provide the most significant benefits to engine operation. In addition, feasibility of using additive manufacturing technologies to fabricate gas turbine engine components from polymer and ceramic matrix composite were demonstrated. A wide variety of prototype components (inlet guide vanes (IGV), acoustic liners, engine access door, were additively manufactured using high temperature polymer materials. Ceramic matrix composite components included first stage nozzle segments and high pressure turbine nozzle segments for a cooled doublet vane. In addition, IGVs and acoustic liners were tested in simulated engine conditions in test rigs. The test results are reported and discussed in detail.

  16. A Fully Non-Metallic Gas Turbine Engine Enabled by Additive Manufacturing

    NASA Technical Reports Server (NTRS)

    Grady, Joseph E.; Halbig, Michael C.; Singh, Mrityunjay

    2015-01-01

    In a NASA Aeronautics Research Institute (NARI) sponsored program entitled "A Fully Non-Metallic Gas Turbine Engine Enabled by Additive Manufacturing", evaluation of emerging materials and additive manufacturing technologies was carried out. These technologies may enable fully non-metallic gas turbine engines in the future. This paper highlights the results of engine system trade studies which were carried out to estimate reduction in engine emissions and fuel burn enabled due to advanced materials and manufacturing processes. A number of key engine components were identified in which advanced materials and additive manufacturing processes would provide the most significant benefits to engine operation. In addition, feasibility of using additive manufacturing technologies to fabricate gas turbine engine components from polymer and ceramic matrix composite were demonstrated. A wide variety of prototype components (inlet guide vanes (IGV), acoustic liners, engine access door) were additively manufactured using high temperature polymer materials. Ceramic matrix composite components included first stage nozzle segments and high pressure turbine nozzle segments for a cooled doublet vane. In addition, IGVs and acoustic liners were tested in simulated engine conditions in test rigs. The test results are reported and discussed in detail.

  17. Mechanical and Fatigue Properties of Additively Manufactured Metallic Materials

    NASA Astrophysics Data System (ADS)

    Yadollahi, Aref

    This study aims to investigate the mechanical and fatigue behavior of additively manufactured metallic materials. Several challenges associated with different metal additive manufacturing (AM) techniques (i.e. laser-powder bed fusion and direct laser deposition) have been addressed experimentally and numerically. Experiments have been carried out to study the effects of process inter-layer time interval--i.e. either building the samples one-at-a-time or multi-at-a-time (in-parallel)--on the microstructural features and mechanical properties of 316L stainless steel samples, fabricated via a direct laser deposition (DLD). Next, the effect of building orientation--i.e. the orientation in which AM parts are built--on microstructure, tensile, and fatigue behaviors of 17-4 PH stainless steel, fabricated via a laser-powder bed fusion (L-PBF) method was investigated. Afterwards, the effect of surface finishing--here, as-built versus machined--on uniaxial fatigue behavior and failure mechanisms of Inconel 718 fabricated via a laser-powder bed fusion technique was sought. The numerical studies, as part of this dissertation, aimed to model the mechanical behavior of AM materials, under monotonic and cyclic loading, based on the observations and findings from the experiments. Despite significant research efforts for optimizing process parameters, achieving a homogenous, defect-free AM product--immediately after fabrication--has not yet been fully demonstrated. Thus, one solution for ensuring the adoption of AM materials for application should center on predicting the variations in mechanical behavior of AM parts based on their resultant microstructure. In this regard, an internal state variable (ISV) plasticity-damage model was employed to quantify the damage evolution in DLD 316L SS, under tensile loading, using the microstructural features associated with the manufacturing process. Finally, fatigue behavior of AM parts has been modeled based on the crack-growth concept

  18. Mechanics of additively manufactured biomaterials.

    PubMed

    Zadpoor, Amir A

    2017-06-01

    Additive manufacturing (3D printing) has found many applications in healthcare including fabrication of biomaterials as well as bioprinting of tissues and organs. Additively manufactured (AM) biomaterials may possess arbitrarily complex micro-architectures that give rise to novel mechanical, physical, and biological properties. The mechanical behavior of such porous biomaterials including their quasi-static mechanical properties and fatigue resistance is not yet well understood. It is particularly important to understand the relationship between the designed micro-architecture (topology) and the resulting mechanical properties. The current special issue is dedicated to understanding the mechanical behavior of AM biomaterials. Although various types of AM biomaterials are represented in the special issue, the primary focus is on AM porous metallic biomaterials. As a prelude to this special issue, this editorial reviews some of the latest findings in the mechanical behavior of AM porous metallic biomaterials so as to describe the current state-of-the-art and set the stage for the other studies appearing in the issue. Some areas that are important for future research are also briefly mentioned. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Effect of layered manufacturing techniques, alloy powders, and layer thickness on metal-ceramic bond strength.

    PubMed

    Ekren, Orhun; Ozkomur, Ahmet; Ucar, Yurdanur

    2018-03-01

    Direct metal laser sintering (DMLS) and direct metal laser melting (DMLM) have become popular for fabricating the metal frameworks of metal-ceramic restorations. How the type of layered manufacturing device, layer thickness, and alloy powder may affect the bond strength of ceramic to metal substructure is unclear. The purpose of this in vitro study was to evaluate the bond strength of dental porcelain to metal frameworks fabricated using different layered manufacturing techniques (DMLS and DMLM), Co-Cr alloy powders, and layer thicknesses and to evaluate whether a correlation exists between the bond strength and the number of ceramic remnants on the metal surface. A total of 75 bar-shaped metal specimens (n=15) were fabricated using either DMLS or DMLM. The powder alloys used were Keramit NP-S and EOS-Cobalt-Chrome SP-2 with layer thicknesses of 20 μm and 30 μm. After ceramic application, the metal-ceramic bond strength was evaluated with a 3-point-bend test. Three-way ANOVA followed by the Tukey honest significance difference test were used for statistical analysis (α=.05). De-bonding surface microstructure was observed with scanning electron microscopy. Energy dispersive spectroscopy analysis was conducted to evaluate the correlation between ceramic remnants on the metal surface and bond strength values. The mean bond strength value of DMLS was significantly higher than that of DMLM. While no statistically significant difference was found between layer thicknesses, alloy powders closely affected bond strength. Statistical comparisons revealed that the highest bond strength could be achieved with DMLS-Cobalt-Chrome SP2-20μm, and the lowest bond strength was observed in DMLS-Keramit NP-S-20μm (P≤.05). No correlation was found between porcelain remnants on the metal surface and bond strength values. The layered manufacturing device and the alloy powders evaluated in the current study closely affected the bond strength of dental porcelain to a metal framework

  20. Design of novel materials for additive manufacturing - Isotropic microstructure and high defect tolerance.

    PubMed

    Günther, J; Brenne, F; Droste, M; Wendler, M; Volkova, O; Biermann, H; Niendorf, T

    2018-01-22

    Electron Beam Melting (EBM) is a powder-bed additive manufacturing technology enabling the production of complex metallic parts with generally good mechanical properties. However, the performance of powder-bed based additively manufactured materials is governed by multiple factors that are difficult to control. Alloys that solidify in cubic crystal structures are usually affected by strong anisotropy due to the formation of columnar grains of preferred orientation. Moreover, processing induced defects and porosity detrimentally influence static and cyclic mechanical properties. The current study presents results on processing of a metastable austenitic CrMnNi steel by EBM. Due to multiple phase transformations induced by intrinsic heat-treatment in the layer-wise EBM process the material develops a fine-grained microstructure almost without a preferred crystallographic grain orientation. The deformation-induced phase transformation yields high damage tolerance and, thus, excellent mechanical properties less sensitive to process-induced inhomogeneities. Various scan strategies were applied to evaluate the width of an appropriate process window in terms of microstructure evolution, porosity and change of chemical composition.

  1. Grain Structure Control of Additively Manufactured Metallic Materials

    PubMed Central

    Faierson, Eric J.

    2017-01-01

    Grain structure control is challenging for metal additive manufacturing (AM). Grain structure optimization requires the control of grain morphology with grain size refinement, which can improve the mechanical properties of additive manufactured components. This work summarizes methods to promote fine equiaxed grains in both the additive manufacturing process and subsequent heat treatment. Influences of temperature gradient, solidification velocity and alloy composition on grain morphology are discussed. Equiaxed solidification is greatly promoted by introducing a high density of heterogeneous nucleation sites via powder rate control in the direct energy deposition (DED) technique or powder surface treatment for powder-bed techniques. Grain growth/coarsening during post-processing heat treatment can be restricted by presence of nano-scale oxide particles formed in-situ during AM. Grain refinement of martensitic steels can also be achieved by cyclic austenitizing in post-processing heat treatment. Evidently, new alloy powder design is another sustainable method enhancing the capability of AM for high-performance components with desirable microstructures.

  2. Additive Manufacturing for Highly Efficient Window Inserts CRADA Report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Roschli, Alex C.; Chesser, Phillip C.; Love, Lonnie J.

    ORNL partnered with the Mackinac Technology Company to demonstrate how additive manufacturing can be used to create highly energy efficient window inserts for retrofit in pre-existing buildings. Many early iterations of the window inserts were fabricated using carbon fiber reinforced thermoplastics and polycarbonate films as a stand in for the low-e coated films produced by the Mackinac Technology Company. After demonstration of the proof of concept, i.e. custom window inserts with tensioned film, the materials used for the manufacture of the frames was more closely examined. Hollow particle-filled syntactic foam and low-density polymer composites formed by expandable microspheres were exploredmore » as the materials used to additively manufacture the frames of the inserts. It was concluded that low-cost retrofit window inserts in custom sizes could be easily fabricated using large scale additive manufacturing. Furthermore, the syntactic and expanded foams developed and tested satisfy the mechanical performance requirements for the application.« less

  3. Towards Production of Additive Manufacturing Grade Metallic Powders on the Battlefield

    DTIC Science & Technology

    2017-10-01

    ARL-RP-0618 ● OCT 2017 US Army Research Laboratory Towards Production of Additive Manufacturing Grade Metallic Powders on the...Research Laboratory Towards Production of Additive Manufacturing Grade Metallic Powders on the Battlefield by Marc Pepi Weapons and...REPORT TYPE Reprint 3. DATES COVERED (From - To) June 2016–June 2017 4. TITLE AND SUBTITLE Towards Production of Additive Manufacturing Grade

  4. Producing Hybrid Metal Composites by Combining Additive Manufacturing and Casting

    DOE PAGES

    Pawlowski, Alex E.; Splitter, Derek A.; Muth, Thomas R.; ...

    2017-10-01

    Additive manufacturing by itself provides many benefits, but by combining different materials processing techniques like traditional casting with additive manufacturing to create hybrid processes, custom materials can be tailor-made and mass produced for applications with specific performance needs.

  5. Additively Manufactured Device for Dynamic Culture of Large Arrays of 3D Tissue Engineered Constructs.

    PubMed

    Costa, Pedro F; Hutmacher, Dietmar W; Theodoropoulos, Christina; Gomes, Manuela E; Reis, Rui L; Vaquette, Cédryck

    2015-04-22

    The ability to test large arrays of cell and biomaterial combinations in 3D environments is still rather limited in the context of tissue engineering and regenerative medicine. This limitation can be generally addressed by employing highly automated and reproducible methodologies. This study reports on the development of a highly versatile and upscalable method based on additive manufacturing for the fabrication of arrays of scaffolds, which are enclosed into individualized perfusion chambers. Devices containing eight scaffolds and their corresponding bioreactor chambers are simultaneously fabricated utilizing a dual extrusion additive manufacturing system. To demonstrate the versatility of the concept, the scaffolds, while enclosed into the device, are subsequently surface-coated with a biomimetic calcium phosphate layer by perfusion with simulated body fluid solution. 96 scaffolds are simultaneously seeded and cultured with human osteoblasts under highly controlled bidirectional perfusion dynamic conditions over 4 weeks. Both coated and noncoated resulting scaffolds show homogeneous cell distribution and high cell viability throughout the 4 weeks culture period and CaP-coated scaffolds result in a significantly increased cell number. The methodology developed in this work exemplifies the applicability of additive manufacturing as a tool for further automation of studies in the field of tissue engineering and regenerative medicine. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Diode-based additive manufacturing of metals using an optically-addressable light valve.

    PubMed

    Matthews, Manyalibo J; Guss, Gabe; Drachenberg, Derrek R; Demuth, James A; Heebner, John E; Duoss, Eric B; Kuntz, Joshua D; Spadaccini, Christopher M

    2017-05-15

    Selective Laser Melting (SLM) of metal powder bed layers, whereby 3D metal objects can be printed from a digital file with unprecedented design flexibility, is spurring manufacturing innovations in medical, automotive, aerospace and textile industries. Because SLM is based on raster-scanning a laser beam over each layer, the process is relatively slow compared to most traditional manufacturing methods (hours to days), thus limiting wider spread use. Here we demonstrate the use of a large area, photolithographic method for 3D metal printing, using an optically-addressable light valve (OALV) as the photomask, to print entire layers of metal powder at once. An optical sheet of multiplexed ~5 kW, 20 ms laser diode and ~1 MW, 7 ns Q-switched laser pulses are used to selectively melt each layer. The patterning of near infrared light is accomplished by imaging 470 nm light onto the transmissive OALV, which consists of polarization-selective nematic liquid crystal sandwiched between a photoconductor and transparent conductor for switching.

  7. Enhancing Surface Finish of Additively Manufactured Titanium and Cobalt Chrome Elements Using Laser Based Finishing

    NASA Astrophysics Data System (ADS)

    Gora, Wojciech S.; Tian, Yingtao; Cabo, Aldara Pan; Ardron, Marcus; Maier, Robert R. J.; Prangnell, Philip; Weston, Nicholas J.; Hand, Duncan P.

    Additive manufacturing (AM) offers the possibility of creating a complex free form object as a single element, which is not possible using traditional mechanical machining. Unfortunately the typically rough surface finish of additively manufactured parts is unsuitable for many applications. As a result AM parts must be post-processed; typically mechanically machined and/or and polished using either chemical or mechanical techniques (both of which have their limitations). Laser based polishing is based on remelting of a very thin surface layer and it offers potential as a highly repeatable, higher speed process capable of selective area polishing, and without any waste problems (no abrasives or liquids). In this paper an in-depth investigation of CW laser polishing of titanium and cobalt chrome AM elements is presented. The impact of different scanning strategies, laser parameters and initial surface condition on the achieved surface finish is evaluated.

  8. Additive Manufacturing of Low Cost Upper Stage Propulsion Components

    NASA Technical Reports Server (NTRS)

    Protz, Christopher; Bowman, Randy; Cooper, Ken; Fikes, John; Taminger, Karen; Wright, Belinda

    2014-01-01

    NASA is currently developing Additive Manufacturing (AM) technologies and design tools aimed at reducing the costs and manufacturing time of regeneratively cooled rocket engine components. These Low Cost Upper Stage Propulsion (LCUSP) tasks are funded through NASA's Game Changing Development Program in the Space Technology Mission Directorate. The LCUSP project will develop a copper alloy additive manufacturing design process and develop and optimize the Electron Beam Freeform Fabrication (EBF3) manufacturing process to direct deposit a nickel alloy structural jacket and manifolds onto an SLM manufactured GRCop chamber and Ni-alloy nozzle. In order to develop these processes, the project will characterize both the microstructural and mechanical properties of the SLMproduced GRCop-84, and will explore and document novel design techniques specific to AM combustion devices components. These manufacturing technologies will be used to build a 25K-class regenerative chamber and nozzle (to be used with tested DMLS injectors) that will be tested individually and as a system in hot fire tests to demonstrate the applicability of the technologies. These tasks are expected to bring costs and manufacturing time down as spacecraft propulsion systems typically comprise more than 70% of the total vehicle cost and account for a significant portion of the development schedule. Additionally, high pressure/high temperature combustion chambers and nozzles must be regeneratively cooled to survive their operating environment, causing their design to be time consuming and costly to build. LCUSP presents an opportunity to develop and demonstrate a process that can infuse these technologies into industry, build competition, and drive down costs of future engines.

  9. Additive Manufacturing: Which DLA-Managed Legacy Parts are Potential AM Candidates

    DTIC Science & Technology

    2016-07-01

    R G ADDITIVE MANUFACTURING : WHICH DLA-MANAGED LEGACY PARTS ARE POTENTIAL AM CANDIDATES? REPORT DL501T1 J UL Y 2016...L Y 2 0 1 6 ADDITIVE MANUFACTURING : WHICH DLA-MANAGED LEGACY PARTS ARE POTENTIAL AM CANDIDATES? REPORT DL501T1 Thomas K . Pa rk s...DESIGNATED BY OTHER OFFICIAL DOCUMENTATION. LMI © 2016. ALL RIGHTS RESERVED. iii Additive Manufacturing : Which DLA-Managed Legacy Parts Are

  10. Additive manufacturing of materials: Opportunities and challenges

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Babu, Sudarsanam Suresh; Love, Lonnie J.; Dehoff, Ryan R.

    Additive manufacturing (also known as 3D printing) is considered a disruptive technology for producing components with topologically optimized complex geometries as well as functionalities that are not achievable by traditional methods. The realization of the full potential of 3D printing is stifled by a lack of computational design tools, generic material feedstocks, techniques for monitoring thermomechanical processes under in situ conditions, and especially methods for minimizing anisotropic static and dynamic properties brought about by microstructural heterogeneity. In this paper, we discuss the role of interdisciplinary research involving robotics and automation, process control, multiscale characterization of microstructure and properties, and high-performancemore » computational tools to address each of these challenges. In addition, emerging pathways to scale up additive manufacturing of structural materials to large sizes (>1 m) and higher productivities (5–20 kg/h) while maintaining mechanical performance and geometrical flexibility are also discussed.« less

  11. Additive manufacturing of materials: Opportunities and challenges

    DOE PAGES

    Babu, Sudarsanam Suresh; Love, Lonnie J.; Dehoff, Ryan R.; ...

    2015-11-01

    Additive manufacturing (also known as 3D printing) is considered a disruptive technology for producing components with topologically optimized complex geometries as well as functionalities that are not achievable by traditional methods. The realization of the full potential of 3D printing is stifled by a lack of computational design tools, generic material feedstocks, techniques for monitoring thermomechanical processes under in situ conditions, and especially methods for minimizing anisotropic static and dynamic properties brought about by microstructural heterogeneity. In this paper, we discuss the role of interdisciplinary research involving robotics and automation, process control, multiscale characterization of microstructure and properties, and high-performancemore » computational tools to address each of these challenges. In addition, emerging pathways to scale up additive manufacturing of structural materials to large sizes (>1 m) and higher productivities (5–20 kg/h) while maintaining mechanical performance and geometrical flexibility are also discussed.« less

  12. Production tolerance of additive manufactured polymeric objects for clinical applications.

    PubMed

    Braian, Michael; Jimbo, Ryo; Wennerberg, Ann

    2016-07-01

    To determine the production tolerance of four commercially available additive manufacturing systems. By reverse engineering annex A and B from the ISO_12836;2012, two geometrical figures relevant to dentistry was obtained. Object A specifies the measurement of an inlay-shaped object and B a multi-unit specimen to simulate a four-unit bridge model. The objects were divided into x, y and z measurements, object A was divided into a total of 16 parameters and object B was tested for 12 parameters. The objects were designed digitally and manufactured by professionals in four different additive manufacturing systems; each system produced 10 samples of each objects. For object A, three manufacturers presented an accuracy of <100μm and one system showed an accuracy of <20μm. For object B, all systems presented an accuracy of <100μm, and most parameters were <40μm. The standard deviation for most parameters were <40μm. The growing interest and use of intra-oral digitizing systems stresses the use of computer aided manufacturing of working models. The additive manufacturing techniques has the potential to help us in the digital workflow. Thus, it is important to have knowledge about production accuracy and tolerances. This study presents a method to test additive manufacturing units for accuracy and repeatability. Copyright © 2016 The Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  13. Living additive manufacturing: Transformation of parent gels into diversely functionalized daughter gels made possible by visible light photoredox catalysis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chen, Mao; Gu, Yuwei; Singh, Awaneesh

    Light-initiated additive manufacturing techniques typically rely on layer-by-layer addition or continuous extraction of polymers formed via nonliving, free radical polymerization methods that render the final materials “dead” toward further monomer insertion; the polymer chains within the materials cannot be reactivated to induce chain extension. An alternative “living additive manufacturing” strategy would involve the use of photocontrolled living radical polymerization to spatiotemporally insert monomers into dormant “parent” materials to generate more complex and diversely functionalized “daughter” materials. Here, we demonstrate a proof-of-concept study of living additive manufacturing using end-linked polymer gels embedded with trithiocarbonate iniferters that can be activated by photoinducedmore » single-electron transfer from an organic photoredox catalyst in solution. This system enables the synthesis of a wide range of chemically and mechanically differentiated daughter gels from a single type of parent gel via light-controlled modification of the parent’s average composition, strand length, and/or cross-linking density. Furthermore, daughter gels that are softer than their parent, stiffer than their parent, larger but with the same modulus as their parent, thermally responsive, polarity responsive, healable, and weldable are all realized.« less

  14. Living Additive Manufacturing: Transformation of Parent Gels into Diversely Functionalized Daughter Gels Made Possible by Visible Light Photoredox Catalysis

    PubMed Central

    2017-01-01

    Light-initiated additive manufacturing techniques typically rely on layer-by-layer addition or continuous extraction of polymers formed via nonliving, free radical polymerization methods that render the final materials “dead” toward further monomer insertion; the polymer chains within the materials cannot be reactivated to induce chain extension. An alternative “living additive manufacturing” strategy would involve the use of photocontrolled living radical polymerization to spatiotemporally insert monomers into dormant “parent” materials to generate more complex and diversely functionalized “daughter” materials. Here, we demonstrate a proof-of-concept study of living additive manufacturing using end-linked polymer gels embedded with trithiocarbonate iniferters that can be activated by photoinduced single-electron transfer from an organic photoredox catalyst in solution. This system enables the synthesis of a wide range of chemically and mechanically differentiated daughter gels from a single type of parent gel via light-controlled modification of the parent’s average composition, strand length, and/or cross-linking density. Daughter gels that are softer than their parent, stiffer than their parent, larger but with the same modulus as their parent, thermally responsive, polarity responsive, healable, and weldable are all realized. PMID:28280779

  15. Living additive manufacturing: Transformation of parent gels into diversely functionalized daughter gels made possible by visible light photoredox catalysis

    DOE PAGES

    Chen, Mao; Gu, Yuwei; Singh, Awaneesh; ...

    2017-01-13

    Light-initiated additive manufacturing techniques typically rely on layer-by-layer addition or continuous extraction of polymers formed via nonliving, free radical polymerization methods that render the final materials “dead” toward further monomer insertion; the polymer chains within the materials cannot be reactivated to induce chain extension. An alternative “living additive manufacturing” strategy would involve the use of photocontrolled living radical polymerization to spatiotemporally insert monomers into dormant “parent” materials to generate more complex and diversely functionalized “daughter” materials. Here, we demonstrate a proof-of-concept study of living additive manufacturing using end-linked polymer gels embedded with trithiocarbonate iniferters that can be activated by photoinducedmore » single-electron transfer from an organic photoredox catalyst in solution. This system enables the synthesis of a wide range of chemically and mechanically differentiated daughter gels from a single type of parent gel via light-controlled modification of the parent’s average composition, strand length, and/or cross-linking density. Furthermore, daughter gels that are softer than their parent, stiffer than their parent, larger but with the same modulus as their parent, thermally responsive, polarity responsive, healable, and weldable are all realized.« less

  16. Characterizations of additive manufactured porous titanium implants.

    PubMed

    Basalah, Ahmad; Shanjani, Yaser; Esmaeili, Shahrzad; Toyserkani, Ehsan

    2012-10-01

    This article describes physical, chemical, and mechanical characterizations of porous titanium implants made by an additive manufacturing method to gain insight into the correlation of process parameters and final physical properties of implants used in orthopedics. For the manufacturing chain, the powder metallurgy technology was combined with the additive manufacturing to fabricate the porous structure from the pure tanium powder. A 3D printing machine was employed in this study to produce porous bar samples. A number of physical parameters such as titanium powder size, polyvinyl alcohol (PVA) amount, sintering temperature and time were investigated to control the mechanical properties and porosity of the structures. The produced samples were characterized through porosity and shrinkage measurements, mechanical compression test and scanning electron microscopy (SEM). The results showed a level of porosity in the samples in the range of 31-43%, which is within the range of the porosity of the cancelluous bone and approaches the range of the porosity of the cortical bone. The results of the mechanical test showed that the compressive strength is in the wide range of 56-509 MPa implying the effect of the process parameters on the mechanical strengths. This technique of manufacturing of Ti porous structures demonstrated a low level of shrinkage with the shrinkage percentage ranging from 1.5 to 5%. Copyright © 2012 Wiley Periodicals, Inc.

  17. Additive Manufacturing Technology for Biomedical Components: A review

    NASA Astrophysics Data System (ADS)

    Aimi Zaharin, Haizum; Rani, Ahmad Majdi Abdul; Lenggo Ginta, Turnad; Azam, Farooq I.

    2018-03-01

    Over the last decades, additive manufacturing has shown potential application in ranging fields. No longer a prototyping technology, it is now being utilised as a manufacturing technology for giant industries such as the automotive, aircraft and recently in the medical industry. It is a very successful method that provides health-care solution in biomedical sectors by producing patient-specific prosthetics, improve tissues engineering and facilitate pre-operating session. This paper thus presents a brief overview of the most commercially important additive manufacturing technologies, which is currently available for fabricating biomedical components such as Stereolithography (SLA), Selective Laser Sintering (SLS), Selective Laser Melting (SLM), Fused Deposition Modelling (FDM) and Electron Beam Melting (EBM). It introduces the basic principles of the main process, highlights some of the beneficial applications in medical industry and the current limitation of applied technology.

  18. Cold Spraying of Armstrong Process Titanium Powder for Additive Manufacturing

    NASA Astrophysics Data System (ADS)

    MacDonald, D.; Fernández, R.; Delloro, F.; Jodoin, B.

    2017-04-01

    Titanium parts are ideally suited for aerospace applications due to their unique combination of high specific strength and excellent corrosion resistance. However, titanium as bulk material is expensive and challenging/costly to machine. Production of complex titanium parts through additive manufacturing looks promising, but there are still many barriers to overcome before reaching mainstream commercialization. The cold gas dynamic spraying process offers the potential for additive manufacturing of large titanium parts due to its reduced reactive environment, its simplicity to operate, and the high deposition rates it offers. A few challenges are to be addressed before the additive manufacturing potential of titanium by cold gas dynamic spraying can be reached. In particular, it is known that titanium is easy to deposit by cold gas dynamic spraying, but the deposits produced are usually porous when nitrogen is used as the carrier gas. In this work, a method to manufacture low-porosity titanium components at high deposition efficiencies is revealed. The components are produced by combining low-pressure cold spray using nitrogen as the carrier gas with low-cost titanium powder produced using the Armstrong process. The microstructure and mechanical properties of additive manufactured titanium components are investigated.

  19. Additively manufactured porous tantalum implants.

    PubMed

    Wauthle, Ruben; van der Stok, Johan; Amin Yavari, Saber; Van Humbeeck, Jan; Kruth, Jean-Pierre; Zadpoor, Amir Abbas; Weinans, Harrie; Mulier, Michiel; Schrooten, Jan

    2015-03-01

    The medical device industry's interest in open porous, metallic biomaterials has increased in response to additive manufacturing techniques enabling the production of complex shapes that cannot be produced with conventional techniques. Tantalum is an important metal for medical devices because of its good biocompatibility. In this study selective laser melting technology was used for the first time to manufacture highly porous pure tantalum implants with fully interconnected open pores. The architecture of the porous structure in combination with the material properties of tantalum result in mechanical properties close to those of human bone and allow for bone ingrowth. The bone regeneration performance of the porous tantalum was evaluated in vivo using an orthotopic load-bearing bone defect model in the rat femur. After 12 weeks, substantial bone ingrowth, good quality of the regenerated bone and a strong, functional implant-bone interface connection were observed. Compared to identical porous Ti-6Al-4V structures, laser-melted tantalum shows excellent osteoconductive properties, has a higher normalized fatigue strength and allows for more plastic deformation due to its high ductility. It is therefore concluded that this is a first step towards a new generation of open porous tantalum implants manufactured using selective laser melting. Copyright © 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  20. Computed Tomography Inspection and Analysis for Additive Manufacturing Components

    NASA Technical Reports Server (NTRS)

    Beshears, Ronald D.

    2017-01-01

    Computed tomography (CT) inspection was performed on test articles additively manufactured from metallic materials. Metallic AM and machined wrought alloy test articles with programmed flaws and geometric features were inspected using a 2-megavolt linear accelerator based CT system. Performance of CT inspection on identically configured wrought and AM components and programmed flaws was assessed to determine the impact of additive manufacturing on inspectability of objects with complex geometries.

  1. Rapid Solidification and Phase Transformations in Additive Manufactured Materials

    DOE PAGES

    Asle Zaeem, Mohsen; Clarke, Amy Jean

    2016-01-14

    Within the past few years, additive manufacturing (AM) has emerged as a promising manufacturing technique to enable the production of complex engineering structures with high efficiency and accuracy. Among the important factors establishing AM as a sustainable manufacturing process is the ability to control the microstructures and properties of AM products. In most AM processes, such as laser sintering (LS), laser melting (LM), and laser metal deposition (LMD), rapid solidification and high-temperature phase transformations play primary roles in determining nano- and microstructures, and consequently the mechanical and other properties of AM products. This topic of JOM is dedicated to summarizingmore » the current research efforts in the area of rapid solidification and phase transformations in additively manufactured materials. Finally, a brief summary follows below of 10 journal articles in this topic.« less

  2. Manufacturing of prestressed piezoelectric unimorphs using a postfired biasing layer.

    PubMed

    Juuti, Jari A; Jantunen, Heli; Moilanen, Veli-Pekka; Leppävuori, Seppo

    2006-05-01

    A novel manufacturing method for prestressed piezoelectric unimorphs is introduced and the actuator properties are examined. Prestressed PZT 5A and PZT 5H unimorphs with piezo material thickness of 250 microm and 375 microm were manufactured by using sintering and thermal shrinkage of the prestressing material. The process was carried out by screen printing a layer of AgPd paste on one side of the sintered bulk ceramic. As an alternative method, dielectric low temperature co-fired ceramic (LTCC) tape was used as the prestressing material. Different configurations were tested to obtain high displacements and to make a comparison between materials. After firing, the samples were poled, and the displacement versus load characteristics of the resulting actuators were investigated. A maximum displacement of 118 microm was obtained from a 250 microm thick, prestressed PZT 5H actuator with a diameter of 25 mm, in which LTCC tape was used as the prestressing layer. Similarly, the PZT 5H material provided a maximum displacement of 63 microm with a screen-printed AgPd prestressing layer. The manufacturing method described offers a novel approach for the production of a wide range of integrated active structures on, for instance, an LTCC circuit board. This is especially important because piezoelectric bulk materials with high piezoelectric coefficients can be used to produce high displacements.

  3. Feasibility and Testing of Additive Manufactured Components

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dehoff, Ryan R.; Hummelt, Ed; Solovyeva, Lyudmila

    2016-09-01

    This project focused on demonstrating the ability to fabricate two parts with different geometry: an arc flash interrupter and a hydraulic manifold. Eaton Corporation provided ORNL solid models, information related to tolerances and sensitive parameters of the parts and provided testing and evaluation. ORNL successfully manufactured both components, provided cost models of the manufacturing (materials, labor, time and post processing) and delivered test components for Eaton evaluation. The arc flash suppressor was fabricated using the Renishaw laser powder bed technology in CoCrMo while the manifold was produced from Ti-6Al-4V using the Arcam electron beam melting technology. These manufacturing techniques weremore » selected based on the design and geometrical tolerances required. A full-scale manifold was produced on the Arcam A2 system (nearly 12 inches tall). A portion of the manifold was also produced in the Arcam Q10 system. Although a full scale manifold could not be produced in the system, a full scale manifold is expected to have similar material properties, geometric accuracy, and surface finish as could be fabricated on an Arcam Q20 system that is capable of producing four full scale manifolds in a production environment. In addition to the manifold, mechanical test specimens, geometric tolerance artifacts, and microstructure samples were produced alongside the manifold. The development and demonstration of these two key components helped Eaton understand the impact additive manufacturing can have on many of their existing products. By working within the MDF and leveraging ORNL’s manufacturing and characterization capabilities, the work will ensure the rapid insertion and commercialization of this technology.« less

  4. Materials Characterization of Additively Manufactured Components for Rocket Propulsion

    NASA Technical Reports Server (NTRS)

    Carter, Robert; Draper, Susan; Locci, Ivan; Lerch, Bradley; Ellis, David; Senick, Paul; Meyer, Michael; Free, James; Cooper, Ken; Jones, Zachary

    2015-01-01

    To advance Additive Manufacturing (AM) technologies for production of rocket propulsion components the NASA Glenn Research Center (GRC) is applying state of the art characterization techniques to interrogate microstructure and mechanical properties of AM materials and components at various steps in their processing. The materials being investigated for upper stage rocket engines include titanium, copper, and nickel alloys. Additive manufacturing processes include laser powder bed, electron beam powder bed, and electron beam wire fed processes. Various post build thermal treatments, including Hot Isostatic Pressure (HIP), have been studied to understand their influence on microstructure, mechanical properties, and build density. Micro-computed tomography, electron microscopy, and mechanical testing in relevant temperature environments has been performed to develop relationships between build quality, microstructure, and mechanical performance at temperature. A summary of GRC's Additive Manufacturing roles and experimental findings will be presented.

  5. Material Characterization of Additively Manufactured Components for Rocket Propulsion

    NASA Technical Reports Server (NTRS)

    Carter, Robert; Draper, Susan; Locci, Ivan; Lerch, Bradley; Ellis, David; Senick, Paul; Meyer, Michael; Free, James; Cooper, Ken; Jones, Zachary

    2015-01-01

    To advance Additive Manufacturing (AM) technologies for production of rocket propulsion components the NASA Glenn Research Center (GRC) is applying state of the art characterization techniques to interrogate microstructure and mechanical properties of AM materials and components at various steps in their processing. The materials being investigated for upper stage rocket engines include titanium, copper, and nickel alloys. Additive manufacturing processes include laser powder bed, electron beam powder bed, and electron beam wire fed processes. Various post build thermal treatments, including Hot Isostatic Pressure (HIP), have been studied to understand their influence on microstructure, mechanical properties, and build density. Micro-computed tomography, electron microscopy, and mechanical testing in relevant temperature environments has been performed to develop relationships between build quality, microstructure, and mechanical performance at temperature. A summary of GRCs Additive Manufacturing roles and experimental findings will be presented.

  6. In-situ acoustic signature monitoring in additive manufacturing processes

    NASA Astrophysics Data System (ADS)

    Koester, Lucas W.; Taheri, Hossein; Bigelow, Timothy A.; Bond, Leonard J.; Faierson, Eric J.

    2018-04-01

    Additive manufacturing is a rapidly maturing process for the production of complex metallic, ceramic, polymeric, and composite components. The processes used are numerous, and with the complex geometries involved this can make quality control and standardization of the process and inspection difficult. Acoustic emission measurements have been used previously to monitor a number of processes including machining and welding. The authors have identified acoustic signature measurement as a potential means of monitoring metal additive manufacturing processes using process noise characteristics and those discrete acoustic emission events characteristic of defect growth, including cracks and delamination. Results of acoustic monitoring for a metal additive manufacturing process (directed energy deposition) are reported. The work investigated correlations between acoustic emissions and process noise with variations in machine state and deposition parameters, and provided proof of concept data that such correlations do exist.

  7. Computed Tomography Inspection and Analysis for Additive Manufacturing Components

    NASA Technical Reports Server (NTRS)

    Beshears, Ronald D.

    2016-01-01

    Computed tomography (CT) inspection was performed on test articles additively manufactured from metallic materials. Metallic AM and machined wrought alloy test articles with programmed flaws were inspected using a 2MeV linear accelerator based CT system. Performance of CT inspection on identically configured wrought and AM components and programmed flaws was assessed using standard image analysis techniques to determine the impact of additive manufacturing on inspectability of objects with complex geometries.

  8. Bio-reinforced composite development for additive manufacturing: Nanocellulose-PLA

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tekinalp, Halil L.; Lu, Yuan; Kunc, Vlastimil

    Additive manufacturing (AM) is transitioning from being only a prototyping method towards becoming a manufacturing technique for the quick production of parts with complex geometries. For the complete realization of this transition, the mechanical properties of the printed parts have to meet the requirements of actual load-bearing structural components. Integration of a reinforcing second phase into a polymer is a viable approach for the improvement of resins mechanical performance. Addition of carbon fibers into acrylonitrile-butadiene-styrene (ABS) has already been shown to improve its mechanical properties compared to the neat ABS resin (both additively manufactured), and led to the manufacture ofmore » world s first 3D-printed car. However, both ABS resin and carbon fibers are petroleum-based products, and there is a continuous search for alternative, bio-sourced, renewable materials as a feedstock for manufacturing. Towards this direction, we have investigated the potential of cellulose nanofibril-reinforced polylactic acid (PLA) resin systems as an alternative. CNF-PLA composite systems with up to 40 wt% CNF loadings were prepared via compression molding technique and tested. Significant improvements in both tensile strength (80%) and elastic modulus (128%) were observed. Filaments prepared from the same compositions were also successfully 3D-printed into tensile testing specimens with up to 30% CNF concentrations, and showed similar improvements in mechanical performance. Although CNFs were not individually dispersed in PLA matrix, they were observed to be well blended with the polymer based on SEM micrographs. In summary, preparation and 3D-printing of a 100% bio-based feedstock material with the mechanical properties comparable to the carbon fiber-ABS system was successfully demonstrated that it can open up new window of opportunities in the additive manufacturing industry. Acknowledgement Research sponsored by the U.S. Department of Energy, Office of

  9. High Temperature Thermoplastic Additive Manufacturing Using Low-Cost, Open-Source Hardware

    NASA Technical Reports Server (NTRS)

    Gardner, John M.; Stelter, Christopher J.; Yashin, Edward A.; Siochi, Emilie J.

    2016-01-01

    Additive manufacturing (or 3D printing) via Fused Filament Fabrication (FFF), also known as Fused Deposition Modeling (FDM), is a process where material is placed in specific locations layer-by-layer to create a complete part. Printers designed for FFF build parts by extruding a thermoplastic filament from a nozzle in a predetermined path. Originally developed for commercial printers, 3D printing via FFF has become accessible to a much larger community of users since the introduction of Reprap printers. These low-cost, desktop machines are typically used to print prototype parts or novelty items. As the adoption of desktop sized 3D printers broadens, there is increased demand for these machines to produce functional parts that can withstand harsher conditions such as high temperature and mechanical loads. Materials meeting these requirements tend to possess better mechanical properties and higher glass transition temperatures (Tg), thus requiring printers with high temperature printing capability. This report outlines the problems and solutions, and includes a detailed description of the machine design, printing parameters, and processes specific to high temperature thermoplastic 3D printing.

  10. Infrared thermography of welding zones produced by polymer extrusion additive manufacturing.

    PubMed

    Seppala, Jonathan E; Migler, Kalman D

    2016-10-01

    In common thermoplastic additive manufacturing (AM) processes, a solid polymer filament is melted, extruded though a rastering nozzle, welded onto neighboring layers and solidified. The temperature of the polymer at each of these stages is the key parameter governing these non-equilibrium processes, but due to its strong spatial and temporal variations, it is difficult to measure accurately. Here we utilize infrared (IR) imaging - in conjunction with necessary reflection corrections and calibration procedures - to measure these temperature profiles of a model polymer during 3D printing. From the temperature profiles of the printed layer (road) and sublayers, the temporal profile of the crucially important weld temperatures can be obtained. Under typical printing conditions, the weld temperature decreases at a rate of approximately 100 °C/s and remains above the glass transition temperature for approximately 1 s. These measurement methods are a first step in the development of strategies to control and model the printing processes and in the ability to develop models that correlate critical part strength with material and processing parameters.

  11. 3D additive manufactured 316L components microstructural features and changes induced by working life cycles

    NASA Astrophysics Data System (ADS)

    Pace, M. L.; Guarnaccio, A.; Dolce, P.; Mollica, D.; Parisi, G. P.; Lettino, A.; Medici, L.; Summa, V.; Ciancio, R.; Santagata, A.

    2017-10-01

    The ability of processing through laser beams different kinds of metallic powders for direct production of 3D components with complex geometries has been gaining an impressive and growing attention for specific industrial applications. The process which can be distinguished as Selective Laser Sintering or Selective Laser Melting is even considered, more generally, as Additive Manufacturing where layer by layer material is built by the interaction between a laser beam and a powder bed. The rapid heating of the powder due to the laser beam energy transfer process followed by a rapid cooling rate induces within the manufactured material a cellular structure with fine sub-grains, which are in the range of few hundreds of micrometers. These metastable structures, which are smaller than the grain size in conventionally manufactured 316L stainless steel components, can undertake towards a recrystallization process due to either heat or mechanical treatments. For instance, when sub-grain boundaries of the cells are enriched with Mo and higher concentration of dislocation, dynamical processes occur generating local residual stresses. In these circumstances the segregation of Mo in cell boundaries is out of thermodynamic equilibrium conditions so that microstructures and phases are metastable. In the range of 1100-1400 °C heat treatments a complete dissolution of Mo in the Fe matrix with a gradual disappearance of sub-microns cell is observed feeding the growth of larger austenitic sub-grains formation. It follows a higher degree of Mo dissolution in the material matrix and a decrease of dislocation's concentration (Saeidi et al., 2015) [1]. In the work here presented we point out which are the microstructural features of stainless steel 316L components realized by Additive Manufacturing. Furthermore, the occurrence of a microstructural evolution is presented after experiencing to fatigue of 80000 cycles some door joints obtained by this technique. A decrease of dislocation

  12. Colloidal-based additive manufacturing of bio-inspired composites

    NASA Astrophysics Data System (ADS)

    Studart, Andre R.

    Composite materials in nature exhibit heterogeneous architectures that are tuned to fulfill the functional demands of the surrounding environment. Examples range from the cellulose-based organic structure of plants to highly mineralized collagen-based skeletal parts like bone and teeth. Because they are often utilized to combine opposing properties such as strength and low-density or stiffness and wear resistance, the heterogeneous architecture of natural materials can potentially address several of the technical limitations of artificial homogeneous composites. However, current man-made manufacturing technologies do not allow for the level of composition and fiber orientation control found in natural heterogeneous systems. In this talk, I will present two additive manufacturing technologies recently developed in our group to build composites with exquisite architectures only rivaled by structures made by living organisms in nature. Since the proposed techniques utilize colloidal suspensions as feedstock, understanding the physics underlying the stability, assembly and rheology of the printing inks is key to predict and control the architecture of manufactured parts. Our results will show that additive manufacturing routes offer a new exciting pathway for the fabrication of biologically-inspired composite materials with unprecedented architectures and functionalities.

  13. Failure mechanisms of additively manufactured porous biomaterials: Effects of porosity and type of unit cell.

    PubMed

    Kadkhodapour, J; Montazerian, H; Darabi, A Ch; Anaraki, A P; Ahmadi, S M; Zadpoor, A A; Schmauder, S

    2015-10-01

    Since the advent of additive manufacturing techniques, regular porous biomaterials have emerged as promising candidates for tissue engineering scaffolds owing to their controllable pore architecture and feasibility in producing scaffolds from a variety of biomaterials. The architecture of scaffolds could be designed to achieve similar mechanical properties as in the host bone tissue, thereby avoiding issues such as stress shielding in bone replacement procedure. In this paper, the deformation and failure mechanisms of porous titanium (Ti6Al4V) biomaterials manufactured by selective laser melting from two different types of repeating unit cells, namely cubic and diamond lattice structures, with four different porosities are studied. The mechanical behavior of the above-mentioned porous biomaterials was studied using finite element models. The computational results were compared with the experimental findings from a previous study of ours. The Johnson-Cook plasticity and damage model was implemented in the finite element models to simulate the failure of the additively manufactured scaffolds under compression. The computationally predicted stress-strain curves were compared with the experimental ones. The computational models incorporating the Johnson-Cook damage model could predict the plateau stress and maximum stress at the first peak with less than 18% error. Moreover, the computationally predicted deformation modes were in good agreement with the results of scaling law analysis. A layer-by-layer failure mechanism was found for the stretch-dominated structures, i.e. structures made from the cubic unit cell, while the failure of the bending-dominated structures, i.e. structures made from the diamond unit cells, was accompanied by the shearing bands of 45°. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Fully printed and integrated electrolyzer cells with additive manufacturing for high-efficiency water splitting

    DOE PAGES

    Yang, Gaoqiang; Mo, Jingke; Kang, Zhenye; ...

    2018-02-20

    Using additive manufacturing (AM) technology, a fundamental material and structure innovation was proposed to significantly increase the energy efficiency, and to reduce the weight, volume and component quantity of proton exchange membrane electrolyzer cells (PEMECs). Four conventional parts (liquid/gas diffusion layer, bipolar plate, gasket, and current distributor) in a PEMEC were integrated into one multifunctional AM plate without committing to tools or molds for the first time. In addition, since the interfacial contact resistances between those parts were eliminated, the comprehensive in-situ characterizations of AM cells showed that an excellent energy efficiency of up to 86.48% was achieved at 2more » A/cm2 and 80 degrees C, and the hydrogen generation rate was increased by 61.81% compared to the conventional cell. More importantly, the highly complex inner structures of the AM integrated multifunctional plates also exhibit the potential to break limitations of conventional manufacture methods for hydrogen generation and to open a door for the development of other energy conversion devices, including fuel cells, solar cells and batteries.« less

  15. Fully printed and integrated electrolyzer cells with additive manufacturing for high-efficiency water splitting

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yang, Gaoqiang; Mo, Jingke; Kang, Zhenye

    Using additive manufacturing (AM) technology, a fundamental material and structure innovation was proposed to significantly increase the energy efficiency, and to reduce the weight, volume and component quantity of proton exchange membrane electrolyzer cells (PEMECs). Four conventional parts (liquid/gas diffusion layer, bipolar plate, gasket, and current distributor) in a PEMEC were integrated into one multifunctional AM plate without committing to tools or molds for the first time. In addition, since the interfacial contact resistances between those parts were eliminated, the comprehensive in-situ characterizations of AM cells showed that an excellent energy efficiency of up to 86.48% was achieved at 2more » A/cm2 and 80 degrees C, and the hydrogen generation rate was increased by 61.81% compared to the conventional cell. More importantly, the highly complex inner structures of the AM integrated multifunctional plates also exhibit the potential to break limitations of conventional manufacture methods for hydrogen generation and to open a door for the development of other energy conversion devices, including fuel cells, solar cells and batteries.« less

  16. Diode-based additive manufacturing of metals using an optically-addressable light valve

    DOE PAGES

    Matthews, Manyalibo J.; Guss, Gabe; Drachenberg, Derrek R.; ...

    2017-05-10

    We present that Selective Laser Melting (SLM) of metal powder bed layers, whereby 3D metal objects can be printed from a digital file with unprecedented design flexibility, is spurring manufacturing innovations in medical, automotive, aerospace and textile industries. Because SLM is based on raster-scanning a laser beam over each layer, the process is relatively slow compared to most traditional manufacturing methods (hours to days), thus limiting wider spread use. Here we demonstrate the use of a large area, photolithographic method for 3D metal printing, using an optically-addressable light valve (OALV) as the photomask, to print entire layers of metal powdermore » at once. An optical sheet of multiplexed ~5 kW, 20 ms laser diode and ~1 MW, 7 ns Q-switched laser pulses are used to selectively melt each layer. Finally, the patterning of near infrared light is accomplished by imaging 470 nm light onto the transmissive OALV, which consists of polarization-selective nematic liquid crystal sandwiched between a photoconductor and transparent conductor for switching.« less

  17. Evaluation of direct and indirect additive manufacture of maxillofacial prostheses.

    PubMed

    Eggbeer, Dominic; Bibb, Richard; Evans, Peter; Ji, Lu

    2012-09-01

    The efficacy of computer-aided technologies in the design and manufacture of maxillofacial prostheses has not been fully proven. This paper presents research into the evaluation of direct and indirect additive manufacture of a maxillofacial prosthesis against conventional laboratory-based techniques. An implant/magnet-retained nasal prosthesis case from a UK maxillofacial unit was selected as a case study. A benchmark prosthesis was fabricated using conventional laboratory-based techniques for comparison against additive manufactured prostheses. For the computer-aided workflow, photogrammetry, computer-aided design and additive manufacture (AM) methods were evaluated in direct prosthesis body fabrication and indirect production using an additively manufactured mould. Qualitative analysis of position, shape, colour and edge quality was undertaken. Mechanical testing to ISO standards was also used to compare the silicone rubber used in the conventional prosthesis with the AM material. Critical evaluation has shown that utilising a computer-aided work-flow can produce a prosthesis body that is comparable to that produced using existing best practice. Technical limitations currently prevent the direct fabrication method demonstrated in this paper from being clinically viable. This research helps prosthesis providers understand the application of a computer-aided approach and guides technology developers and researchers to address the limitations identified.

  18. New layer-based imaging and rapid prototyping techniques for computer-aided design and manufacture of custom dental restoration.

    PubMed

    Lee, M-Y; Chang, C-C; Ku, Y C

    2008-01-01

    Fixed dental restoration by conventional methods greatly relies on the skill and experience of the dental technician. The quality and accuracy of the final product depends mostly on the technician's subjective judgment. In addition, the traditional manual operation involves many complex procedures, and is a time-consuming and labour-intensive job. Most importantly, no quantitative design and manufacturing information is preserved for future retrieval. In this paper, a new device for scanning the dental profile and reconstructing 3D digital information of a dental model based on a layer-based imaging technique, called abrasive computer tomography (ACT) was designed in-house and proposed for the design of custom dental restoration. The fixed partial dental restoration was then produced by rapid prototyping (RP) and computer numerical control (CNC) machining methods based on the ACT scanned digital information. A force feedback sculptor (FreeForm system, Sensible Technologies, Inc., Cambridge MA, USA), which comprises 3D Touch technology, was applied to modify the morphology and design of the fixed dental restoration. In addition, a comparison of conventional manual operation and digital manufacture using both RP and CNC machining technologies for fixed dental restoration production is presented. Finally, a digital custom fixed restoration manufacturing protocol integrating proposed layer-based dental profile scanning, computer-aided design, 3D force feedback feature modification and advanced fixed restoration manufacturing techniques is illustrated. The proposed method provides solid evidence that computer-aided design and manufacturing technologies may become a new avenue for custom-made fixed restoration design, analysis, and production in the 21st century.

  19. Numerical investigation of the mechanical properties of the additive manufactured bone scaffolds fabricated by FDM: The effect of layer penetration and post-heating.

    PubMed

    Naghieh, S; Karamooz Ravari, M R; Badrossamay, M; Foroozmehr, E; Kadkhodaei, M

    2016-06-01

    In recent years, thanks to additive manufacturing technology, researchers have gone towards the optimization of bone scaffolds for the bone reconstruction. Bone scaffolds should have appropriate biological as well as mechanical properties in order to play a decisive role in bone healing. Since the fabrication of scaffolds is time consuming and expensive, numerical methods are often utilized to simulate their mechanical properties in order to find a nearly optimum one. Finite element analysis is one of the most common numerical methods that is used in this regard. In this paper, a parametric finite element model is developed to assess the effects of layers penetration׳s effect on inter-layer adhesion, which is reflected on the mechanical properties of bone scaffolds. To be able to validate this model, some compression test specimens as well as bone scaffolds are fabricated with biocompatible and biodegradable poly lactic acid using fused deposition modeling. All these specimens are tested in compression and their elastic modulus is obtained. Using the material parameters of the compression test specimens, the finite element analysis of the bone scaffold is performed. The obtained elastic modulus is compared with experiment indicating a good agreement. Accordingly, the proposed finite element model is able to predict the mechanical behavior of fabricated bone scaffolds accurately. In addition, the effect of post-heating of bone scaffolds on their elastic modulus is investigated. The results demonstrate that the numerically predicted elastic modulus of scaffold is closer to experimental outcomes in comparison with as-built samples. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Additive Manufacturing of Wind Turbine Molds

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Post, Brian; Richardson, Bradley; Lloyd, Peter

    The objective of this project was to explore the utility of Big Area Additive Manufacturing (BAAM) for low cost manufacturing of wind turbine molds. Engineers at Oak Ridge National Laboratory (ORNL) and TPI Composites (TPI) collaborated to design and manufacture a printed mold that can be used for resin infusion of wind turbine components. Specific focus was on required material properties (operating temperatures and pressures, coefficient of thermal expansion (CTE), thermal conductivity), surface finish (accuracy and coatings) and system integration (integrated vacuum ports, and heating element). The project began with a simple proof of principle components, targeting surface coatings andmore » material properties for printing a small section (approximately 4’ x 4’ x 2’) of a mold. Next, the second phase scaled up and integrated with the objective of capturing all of the necessary components (integrated heating to accelerate cure time, and vacuum, sealing) for resin infusion on a mold of significant size (8’ x 20’ x 6’).« less

  1. Additive manufacturing of RF absorbers

    NASA Astrophysics Data System (ADS)

    Mills, Matthew S.

    The ability of additive manufacturing techniques to fabricate integrated electromagnetic absorbers tuned for specific radio frequency bands within structural composites allows for unique combinations of mechanical and electromagnetic properties. These composites and films can be used for RF shielding of sensitive electromagnetic components through in-plane and out-of-plane RF absorption. Structural composites are a common building block of many commercial platforms. These platforms may be placed in situations in which there is a need for embedded RF absorbing properties along with structural properties. Instead of adding radar absorbing treatments to the external surface of existing structures, which adds increased size, weight and cost; it could prove to be advantageous to integrate the microwave absorbing properties directly into the composite during the fabrication process. In this thesis, a method based on additive manufacturing techniques of composites structures with prescribed electromagnetic loss, within the frequency range 1 to 26GHz, is presented. This method utilizes screen printing and nScrypt micro dispensing to pattern a carbon based ink onto low loss substrates. The materials chosen for this study will be presented, and the fabrication technique that these materials went through to create RF absorbing structures will be described. The calibration methods used, the modeling of the RF structures, and the applications in which this technology can be utilized will also be presented.

  2. Analysis of Additive Manufacturing for Sustainment of Naval Aviation Systems

    DTIC Science & Technology

    2017-09-01

    selection methodology to query the aviation spare-parts inventory for identification of additive manufacturing candidates. The methodology organizes...a component selection methodology to query the aviation spare-parts inventory for identification of additive manufacturing candidates. The... methodology organizes the resultant data using a top-down approach that aligns technical feasibility with programmatic objectives. Finally, a discrete event

  3. Additive manufacturing of short and mixed fibre-reinforced polymer

    DOEpatents

    Lewicki, James; Duoss, Eric B.; Rodriguez, Jennifer Nicole; Worsley, Marcus A.; King, Michael J.

    2018-01-09

    Additive manufacturing of a fiber-reinforced polymer (FRP) product using an additive manufacturing print head; a reservoir in the additive manufacturing print head; short carbon fibers in the reservoir, wherein the short carbon fibers are randomly aligned in the reservoir; an acrylate, methacrylate, epoxy, cyanate ester or isocyanate resin in the reservoir, wherein the short carbon fibers are dispersed in the acrylate, methacrylate, epoxy, cyanate ester or isocyanate resin; a tapered nozzle in the additive manufacturing print head operatively connected to the reservoir, the tapered nozzle produces an extruded material that forms the fiber-reinforced polymer product; baffles in the tapered nozzle that receive the acrylate, methacrylate, epoxy, cyanate ester or isocyanate resin with the short carbon fibers dispersed in the acrylate, methacrylate, epoxy, cyanate ester or isocyanate resin; and a system for driving the acrylate, methacrylate, epoxy, cyanate ester or isocyanate resin with the short carbon fibers dispersed in the acrylate, methacrylate, epoxy, cyanate ester or isocyanate resin from the reservoir through the tapered nozzle wherein the randomly aligned short carbon fibers in the acrylate, methacrylate, epoxy, cyanate ester or isocyanate resin are aligned by the baffles and wherein the extruded material has the short carbon fibers aligned in the acrylate, methacrylate, epoxy, cyanate ester or isocyanate resin that forms the fiber-reinforced polymer product.

  4. Additive Manufacturing of Dense Hexagonal Boron Nitride Objects

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Marquez Rossy, Andres E.; Armstrong, Beth L.; Elliott, Amy M.

    The feasibility of manufacturing hexagonal boron nitride objects via additive manufacturing techniques was investigated. It was demonstrated that it is possible to hot-extrude thermoplastic filaments containing uniformly distributed boron nitride particles with a volume concentration as high as 60% and that these thermoplastic filaments can be used as feedstock for 3D-printing objects using a fused deposition system. Objects 3D-printed by fused deposition were subsequently sintered at high temperature to obtain dense ceramic products. In a parallel study the behavior of hexagonal boron nitride in aqueous solutions was investigated. It was shown that the addition of a cationic dispersant to anmore » azeotrope enabled the formulation of slurries with a volume concentration of boron nitride as high as 33%. Although these slurries exhibited complex rheological behavior, the results from this study are encouraging and provide a pathway for manufacturing hexagonal boron nitride objects via robocasting.« less

  5. Evolution of solidification texture during additive manufacturing

    PubMed Central

    Wei, H. L.; Mazumder, J.; DebRoy, T.

    2015-01-01

    Striking differences in the solidification textures of a nickel based alloy owing to changes in laser scanning pattern during additive manufacturing are examined based on theory and experimental data. Understanding and controlling texture are important because it affects mechanical and chemical properties. Solidification texture depends on the local heat flow directions and competitive grain growth in one of the six <100> preferred growth directions in face centered cubic alloys. Therefore, the heat flow directions are examined for various laser beam scanning patterns based on numerical modeling of heat transfer and fluid flow in three dimensions. Here we show that numerical modeling can not only provide a deeper understanding of the solidification growth patterns during the additive manufacturing, it also serves as a basis for customizing solidification textures which are important for properties and performance of components. PMID:26553246

  6. Evolution of solidification texture during additive manufacturing.

    PubMed

    Wei, H L; Mazumder, J; DebRoy, T

    2015-11-10

    Striking differences in the solidification textures of a nickel based alloy owing to changes in laser scanning pattern during additive manufacturing are examined based on theory and experimental data. Understanding and controlling texture are important because it affects mechanical and chemical properties. Solidification texture depends on the local heat flow directions and competitive grain growth in one of the six <100> preferred growth directions in face centered cubic alloys. Therefore, the heat flow directions are examined for various laser beam scanning patterns based on numerical modeling of heat transfer and fluid flow in three dimensions. Here we show that numerical modeling can not only provide a deeper understanding of the solidification growth patterns during the additive manufacturing, it also serves as a basis for customizing solidification textures which are important for properties and performance of components.

  7. Evolution of solidification texture during additive manufacturing

    DOE PAGES

    Wei, H. L.; Mazumder, J.; DebRoy, T.

    2015-11-10

    Striking differences in the solidification textures of a nickel based alloy owing to changes in laser scanning pattern during additive manufacturing are examined based on theory and experimental data. Understanding and controlling texture are important because it affects mechanical and chemical properties. Solidification texture depends on the local heat flow directions and competitive grain growth in one of the six <100> preferred growth directions in face centered cubic alloys. Furthermore, the heat flow directions are examined for various laser beam scanning patterns based on numerical modeling of heat transfer and fluid flow in three dimensions. Here we show that numericalmore » modeling can not only provide a deeper understanding of the solidification growth patterns during the additive manufacturing, it also serves as a basis for customizing solidification textures which are important for properties and performance of components.« less

  8. Characterization of Effect of Support Structures in Laser Additive Manufacturing of Stainless Steel

    NASA Astrophysics Data System (ADS)

    Järvinen, Jukka-Pekka; Matilainen, Ville; Li, Xiaoyun; Piili, Heidi; Salminen, Antti; Mäkelä, Ismo; Nyrhilä, Olli

    Laser additive manufacturing (LAM) of stainless steel is a layer wisetechnology for fabricating 3D parts from metal powder via selectively melting powder with laser beam. Support structures play a significant role in LAM process as they help to remove heat away from the process and on the other hand hold the work piece in its place. A successful design of support structures can help to achievea building process fast and inexpensive with high quality. Aimof this study was to characterize the usability of two types of support structures: web and tube supports. Purpose of this studywas also to analyze how suitable they are in two industrial application cases: case for dental application and case for jewelry application. It was concluded that the removability of web supports was much better than tube supports. It was noticed that support structures are an important part of LAM process and they strongly affect the manufacturability and the end quality of the part.

  9. Solving the Big Data (BD) Problem in Advanced Manufacturing (Subcategory for work done at Georgia Tech. Study Process and Design Factors for Additive Manufacturing Improvement)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Clark, Brett W.; Diaz, Kimberly A.; Ochiobi, Chinaza Darlene

    2015-09-01

    3D printing originally known as additive manufacturing is a process of making 3 dimensional solid objects from a CAD file. This ground breaking technology is widely used for industrial and biomedical purposes such as building objects, tools, body parts and cosmetics. An important benefit of 3D printing is the cost reduction and manufacturing flexibility; complex parts are built at the fraction of the price. However, layer by layer printing of complex shapes adds error due to the surface roughness. Any such error results in poor quality products with inaccurate dimensions. The main purpose of this research is to measure themore » amount of printing errors for parts with different geometric shapes and to analyze them for finding optimal printing settings to minimize the error. We use a Design of Experiments framework, and focus on studying parts with cone and ellipsoid shapes. We found that the orientation and the shape of geometric shapes have significant effect on the printing error. From our analysis, we also determined the optimal orientation that gives the least printing error.« less

  10. Fatigue Life of Titanium Alloys Fabricated by Additive Layer Manufacturing Techniques for Dental Implants

    NASA Astrophysics Data System (ADS)

    Chan, Kwai S.; Koike, Marie; Mason, Robert L.; Okabe, Toru

    2013-02-01

    Additive layer deposition techniques such as electron beam melting (EBM) and laser beam melting (LBM) have been utilized to fabricate rectangular plates of Ti-6Al-4V with extra low interstitial (ELI) contents. The layer-by-layer deposition techniques resulted in plates that have different surface finishes which can impact significantly on the fatigue life by providing potential sites for fatigue cracks to initiate. The fatigue life of Ti-6Al-4V ELI alloys fabricated by EBM and LBM deposition techniques was investigated by three-point testing of rectangular beams of as-fabricated and electro-discharge machined surfaces under stress-controlled conditions at 10 Hz until complete fracture. Fatigue life tests were also performed on rolled plates of Ti-6Al-4V ELI, regular Ti-6Al-4V, and CP Ti as controls. Fatigue surfaces were characterized by scanning electron microscopy to identify the crack initiation site in the various types of specimen surfaces. The fatigue life data were analyzed statistically using both analysis of variance techniques and the Kaplan-Meier survival analysis method with the Gehan-Breslow test. The results indicate that the LBM Ti-6Al-4V ELI material exhibits a longer fatigue life than the EBM counterpart and CP Ti, but a shorter fatigue life compared to rolled Ti-6Al-4V ELI. The difference in the fatigue life behavior may be largely attributed to the presence of rough surface features that act as fatigue crack initiation sites in the EBM material.

  11. Biocompatibility of hydroxyapatite scaffolds processed by lithography-based additive manufacturing.

    PubMed

    Tesavibul, Passakorn; Chantaweroad, Surapol; Laohaprapanon, Apinya; Channasanon, Somruethai; Uppanan, Paweena; Tanodekaew, Siriporn; Chalermkarnnon, Prasert; Sitthiseripratip, Kriskrai

    2015-01-01

    The fabrication of hydroxyapatite scaffolds for bone tissue engineering applications by using lithography-based additive manufacturing techniques has been introduced due to the abilities to control porous structures with suitable resolutions. In this research, the use of hydroxyapatite cellular structures, which are processed by lithography-based additive manufacturing machine, as a bone tissue engineering scaffold was investigated. The utilization of digital light processing system for additive manufacturing machine in laboratory scale was performed in order to fabricate the hydroxyapatite scaffold, of which biocompatibilities were eventually evaluated by direct contact and cell-culturing tests. In addition, the density and compressive strength of the scaffolds were also characterized. The results show that the hydroxyapatite scaffold at 77% of porosity with 91% of theoretical density and 0.36 MPa of the compressive strength are able to be processed. In comparison with a conventionally sintered hydroxyapatite, the scaffold did not present any cytotoxic signs while the viability of cells at 95.1% was reported. After 14 days of cell-culturing tests, the scaffold was able to be attached by pre-osteoblasts (MC3T3-E1) leading to cell proliferation and differentiation. The hydroxyapatite scaffold for bone tissue engineering was able to be processed by the lithography-based additive manufacturing machine while the biocompatibilities were also confirmed.

  12. Solid-State Additive Manufacturing for Heat Exchangers

    NASA Astrophysics Data System (ADS)

    Norfolk, Mark; Johnson, Hilary

    2015-03-01

    Energy densities in devices are increasing across many industries including power generation, high power electronics, manufacturing, and automotive. Increasingly, there is a need for very high efficiency thermal management devices that can pull heat out of a small area at higher and higher rates. Metal additive manufacturing (AM) technologies have the promise of creating parts with complex internal geometries required for integral thermal management. However, this goal has not been met due to constraints in fusion-based metal 3D printers. This work presents a new strategy for metal AM of heat exchangers using an ultrasonic sheet lamination approach.

  13. Ceramic Stereolithography: Additive Manufacturing for Ceramics by Photopolymerization

    NASA Astrophysics Data System (ADS)

    Halloran, John W.

    2016-07-01

    Ceramic stereolithography and related additive manufacturing methods involving photopolymerization of ceramic powder suspensions are reviewed in terms of the capabilities of current devices. The practical fundamentals of the cure depth, cure width, and cure profile are related to the optical properties of the monomer, ceramic, and photo-active components. Postpolymerization steps, including harvesting and cleaning the objects, binder burnout, and sintering, are discussed and compared with conventional methods. The prospects for practical manufacturing are discussed.

  14. Evaluation of Additive Manufacturing for Composite Part Molds

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Duty, Chad E.; Springfield, Robert M.

    2015-02-01

    The ORNL Manufacturing Demonstration Facility (MDF) collaborated with Tru-Design to test the quality and durability of molds used for making fiber reinforced composites using additive manufacturing. The partners developed surface treatment techniques including epoxy coatings and machining to improve the quality of the surface finish. Test samples made using the printed and surface finished molds demonstrated life spans suitable for one-of-a-kind and low-volume applications, meeting the project objective.

  15. Advanced Methods for Direct Ink Write Additive Manufacturing

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Compel, W. S.; Lewicki, J. P.

    Lawrence Livermore National Laboratory is one of the world’s premier labs for research and development of additive manufacturing processes. Out of these many processes, direct ink write (DIW) is arguably one of the most relevant for the manufacture of architected polymeric materials, components and hardware. However, a bottleneck in this pipeline that has largely been ignored to date is the lack of advanced software implementation with respect to toolpath execution. There remains to be a convenient, automated method to design and produce complex parts that is user-friendly and enabling for the realization of next generation designs and structures. For amore » material to be suitable as a DIW ink it must possess the appropriate rheological properties for this process. Most importantly, the material must exhibit shear-thinning in order to extrude through a print head and have a rapid recovery of its static shear modulus. This makes it possible for the extrudate to be self-supporting upon exiting the print head. While this and other prerequisites narrow the scope of ‘offthe- shelf’ printable materials directly amenable to DIW, the process still tolerates a wide range of potential feedstock materials. These include metallic alloys, inorganic solvent borne dispersions, polymeric melts, filler stabilized monomer compositions, pre-elastomeric feedstocks and thermoset resins each of which requires custom print conditions tailored to the individual ink. As such, an ink perfectly suited for DIW may be prematurely determined to be undesirable for the process if printed under the wrong conditions. Defining appropriate print conditions such as extrusion rate, layer height, and maximum bridge length is a vital first step in validating an ink’s DIW capability.« less

  16. IR-laser assisted additive freeform optics manufacturing.

    PubMed

    Hong, Zhihan; Liang, Rongguang

    2017-08-02

    Computer-controlled additive manufacturing (AM) processes, also known as three-dimensional (3D) printing, create 3D objects by the successive adding of a material or materials. While there have been tremendous developments in AM, the 3D printing of optics is lagging due to the limits in materials and tight requirements for optical applicaitons. We propose a new precision additive freeform optics manufacturing (AFOM) method using an pulsed infrared (IR) laser. Compared to ultraviolet (UV) curable materials, thermally curable optical silicones have a number of advantages, such as strong UV stability, non-yellowing, and high transmission, making it particularly suitable for optical applications. Pulsed IR laser radiation offers a distinct advantage in processing optical silicones, as the high peak intensity achieved in the focal region allows for curing the material quickly, while the brief duration of the laser-material interaction creates a negligible heat-affected zone.

  17. Additive Manufacturing of Fuel Injectors

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sadek Tadros, Dr. Alber Alphonse; Ritter, Dr. George W.; Drews, Charles Donald

    Additive manufacturing (AM), also known as 3D-printing, has been shifting from a novelty prototyping paradigm to a legitimate manufacturing tool capable of creating components for highly complex engineered products. An emerging AM technology for producing metal parts is the laser powder bed fusion (L-PBF) process; however, industry manufacturing specifications and component design practices for L-PBF have not yet been established. Solar Turbines Incorporated (Solar), an industrial gas turbine manufacturer, has been evaluating AM technology for development and production applications with the desire to enable accelerated product development cycle times, overall turbine efficiency improvements, and supply chain flexibility relative to conventionalmore » manufacturing processes (casting, brazing, welding). Accordingly, Solar teamed with EWI on a joint two-and-a-half-year project with the goal of developing a production L-PBF AM process capable of consistently producing high-nickel alloy material suitable for high temperature gas turbine engine fuel injector components. The project plan tasks were designed to understand the interaction of the process variables and their combined impact on the resultant AM material quality. The composition of the high-nickel alloy powders selected for this program met the conventional cast Hastelloy X compositional limits and were commercially available in different particle size distributions (PSD) from two suppliers. Solar produced all the test articles and both EWI and Solar shared responsibility for analyzing them. The effects of powder metal input stock, laser parameters, heat treatments, and post-finishing methods were evaluated. This process knowledge was then used to generate tensile, fatigue, and creep material properties data curves suitable for component design activities. The key process controls for ensuring consistent material properties were documented in AM powder and process specifications. The basic components of the

  18. Additive manufacturing method for SRF components of various geometries

    DOEpatents

    Rimmer, Robert; Frigola, Pedro E; Murokh, Alex Y

    2015-05-05

    An additive manufacturing method for forming nearly monolithic SRF niobium cavities and end group components of arbitrary shape with features such as optimized wall thickness and integral stiffeners, greatly reducing the cost and technical variability of conventional cavity construction. The additive manufacturing method for forming an SRF cavity, includes atomizing niobium to form a niobium powder, feeding the niobium powder into an electron beam melter under a vacuum, melting the niobium powder under a vacuum in the electron beam melter to form an SRF cavity; and polishing the inside surface of the SRF cavity.

  19. Microstructural evolution and mechanical property of Ti-6Al-4V wall deposited by continuous plasma arc additive manufacturing without post heat treatment.

    PubMed

    Lin, Jianjun; Lv, Yaohui; Liu, Yuxin; Sun, Zhe; Wang, Kaibo; Li, Zhuguo; Wu, Yixiong; Xu, Binshi

    2017-05-01

    Plasma arc additive manufacturing (PAM) is a novel additive manufacturing (AM) technology due to its big potential in improving efficiency, convenience and being cost-savings compared to other AM processes of high energy bea\\m. In this research, several Ti-6Al-4V thin walls were deposited by optimized weld wire-feed continuous PAM process (CPAM), in which the heat input was gradually decreased layer by layer. The deposited thin wall consisted of various morphologies, which includes epitaxial growth of prior β grains, horizontal layer bands, martensite and basket weave microstructure, that depends on the heat input, multiple thermal cycles and gradual cooling rate in the deposition process. By gradually reducing heat input of each bead and using continuous current in the PAM process, the average yield strength (YS), ultimate tensile strength (UTS) and elongation reach about 877MPa, 968MPa and 1.5%, respectively, which exceed the standard level of forging. The mechanical property was strengthened and toughened due to weakening the aspect ratio of prior β grains and separating nano-dispersoids among α lamellar. Furthermore, this research demonstrates that the CPAM process has a potential to manufacture or remanufacture in AM components of metallic biomaterials without post-processing heat treatment. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Additive Manufacturing of Metastable Beta Titanium Alloys

    NASA Astrophysics Data System (ADS)

    Yannetta, Christopher J.

    Additive manufacturing processes of many alloys are known to develop texture during the deposition process due to the rapid reheating and the directionality of the dissipation of heat. Titanium alloys and with respect to this study beta titanium alloys are especially susceptible to these effects. This work examines Ti-20wt%V and Ti-12wt%Mo deposited under normal additive manufacturing process parameters to examine the texture of these beta-stabilized alloys. Both microstructures contained columnar prior beta grains 1-2 mm in length beginning at the substrate with no visible equiaxed grains. This microstructure remained constant in the vanadium system throughout the build. The microstructure of the alloy containing molybdenum changed from a columnar to an equiaxed structure as the build height increased. Eighteen additional samples of the Ti-Mo system were created under different processing parameters to identify what role laser power and travel speed have on the microstructure. There appears to be a correlation in alpha lath size and power density. The two binary alloys were again deposited under the same conditions with the addition of 0.5wt% boron to investigate the effects an insoluble interstitial alloying element would have on the microstructure. The size of the prior beta grains in these two alloys were reduced with the addition of boron by approximately 50 (V) and 100 (Mo) times.

  1. The role of nanocrystalline binder metallic coating into WC after additive manufacturing

    NASA Astrophysics Data System (ADS)

    Cavaleiro, A. J.; Fernandes, C. M.; Farinha, A. R.; Gestel, C. V.; Jhabvala, J.; Boillat, E.; Senos, A. M. R.; Vieira, M. T.

    2018-01-01

    Tungsten carbide with microsized particle powders are commonly used embedded in a tough binder metal. The application of these composites is not limited to cutting tools, WC based material has been increasingly used in gaskets and other mechanical parts with complex geometries. Consequently, additive manufacturing processes as Selective Laser Sintering (SLS) might be the solution to overcome some of the manufacturing problems. However, the use of SLS leads to resolve the problems resulting from difference of physical properties between tungsten carbide and the metallic binder, such as laser absorbance and thermal conductivity. In this work, an original approach of powder surface modification was considered to prepare WC-metal composite powders and overcome these constraints, consisting on the sputter-coating of the WC particle surfaces with a nanocrystalline thin film of metallic binder material (stainless steel). The coating improves the thermal behavior and rheology of the WC particles and, at the same time, ensures a binder homogenous distribution. The feasibility of the SLS technology as manufacturing process for WC powder sputter-coated with 13 wt% stainless steel AISI 304L was explored with different laser power and scanning speed parameters. The SLS layers were characterized regarding elemental distribution, phase composition and morphology, and the results are discussed emphasizing the role of the coating on the consolidation process.

  2. The scope of additive manufacturing in cryogenics, component design, and applications

    NASA Astrophysics Data System (ADS)

    Stautner, W.; Vanapalli, S.; Weiss, K.-P.; Chen, R.; Amm, K.; Budesheim, E.; Ricci, J.

    2017-12-01

    Additive manufacturing techniques using composites or metals are rapidly gaining momentum in cryogenic applications. Small or large, complex structural components are now no longer limited to mere design studies but can now move into the production stream thanks to new machines on the market that allow for light-weight, cost optimized designs with short turnaround times. The potential for cost reductions from bulk materials machined to tight tolerances has become obvious. Furthermore, additive manufacturing opens doors and design space for cryogenic components that to date did not exist or were not possible in the past, using bulk materials along with elaborate and expensive machining processes, e.g. micromachining. The cryogenic engineer now faces the challenge to design toward those new additive manufacturing capabilities. Additionally, re-thinking designs toward cost optimization and fast implementation also requires detailed knowledge of mechanical and thermal properties at cryogenic temperatures. In the following we compile the information available to date and show a possible roadmap for additive manufacturing applications of parts and components typically used in cryogenic engineering designs.

  3. Additive Manufacturing in the Marine Corps

    DTIC Science & Technology

    2015-06-01

    commonly referred to as 3D printing. This thesis answers the question of how additive manufacturing can improve the effectiveness of Marine Corps...analysis of current and future 3D -printing processes, examination of several civilian and military examples, and examination of the impact across...fully integrating 3D printers, such as the lack of certification and qualification standards, unreliable end product results, and determining ownership

  4. Validation of Reverse-Engineered and Additive-Manufactured Microsurgical Instrument Prototype.

    PubMed

    Singh, Ramandeep; Suri, Ashish; Anand, Sneh; Baby, Britty

    2016-12-01

    With advancements in imaging techniques, neurosurgical procedures are becoming highly precise and minimally invasive, thus demanding development of new ergonomically aesthetic instruments. Conventionally, neurosurgical instruments are manufactured using subtractive manufacturing methods. Such a process is complex, time-consuming, and impractical for prototype development and validation of new designs. Therefore, an alternative design process has been used utilizing blue light scanning, computer-aided designing, and additive manufacturing direct metal laser sintering (DMLS) for microsurgical instrument prototype development. Deviations of DMLS-fabricated instrument were studied by superimposing scan data of fabricated instrument with the computer-aided designing model. Content and concurrent validity of the fabricated prototypes was done by a group of 15 neurosurgeons by performing sciatic nerve anastomosis in small laboratory animals. Comparative scoring was obtained for the control and study instrument. T test was applied to the individual parameters and P values for force (P < .0001) and surface roughness (P < .01) were found to be statistically significant. These 2 parameters were further analyzed using objective measures. Results depicts that additive manufacturing by DMLS provides an effective method for prototype development. However, direct application of these additive-manufactured instruments in the operating room requires further validation. © The Author(s) 2016.

  5. 40 CFR 80.1613 - Standards and other requirements for gasoline additive manufacturers and blenders.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... gasoline additive manufacturers and blenders. 80.1613 Section 80.1613 Protection of Environment... Gasoline Sulfur § 80.1613 Standards and other requirements for gasoline additive manufacturers and blenders. Gasoline additive manufacturers and blenders must meet the following requirements: (a) Gasoline additive...

  6. Solar Sintering for Additive Manufacturing on the Moon

    NASA Astrophysics Data System (ADS)

    Fateri, M.; Meurisse, A.; Sperl, M.

    2017-09-01

    This study investigates solar sintering of lunar regolith for Additive Manufacturing (AM) purposes on the Moon. In this study, multiple interlocking elements are fabricated for future Lunar habitat developments.

  7. Complex shaped boron carbides from negative additive manufacturing

    DOE PAGES

    Lu, Ryan; Chandrasekaran, Swetha; Du Frane, Wyatt L.; ...

    2018-03-13

    In this paper, complex shaped boron carbide with carbon (B 4C/C) at near-full densities were achieved for the first time using negative additive manufacturing techniques via gelcasting. Negative additive manufacturing involves 3D printing of sacrificial molds used for casting negative copies. B 4C powder distributions and rheology of suspensions were optimized to successfully cast complex shapes. In addition to demonstrating scalability of these complex geometries, hierarchically meso-porous structures were also shown to be possible from this technique. Resorcinol-Formaldehyde (RF) polymer was selected as the gelling agent and can also pyrolyze into a carbon aerogel network to act as the sinteringmore » aid for B 4C. Finally, due to the highly effective distribution of in situ carbon for the B 4C matrix, near-full sintered density of 97–98% of theoretical maximum density was achieved.« less

  8. Complex shaped boron carbides from negative additive manufacturing

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lu, Ryan; Chandrasekaran, Swetha; Du Frane, Wyatt L.

    In this paper, complex shaped boron carbide with carbon (B 4C/C) at near-full densities were achieved for the first time using negative additive manufacturing techniques via gelcasting. Negative additive manufacturing involves 3D printing of sacrificial molds used for casting negative copies. B 4C powder distributions and rheology of suspensions were optimized to successfully cast complex shapes. In addition to demonstrating scalability of these complex geometries, hierarchically meso-porous structures were also shown to be possible from this technique. Resorcinol-Formaldehyde (RF) polymer was selected as the gelling agent and can also pyrolyze into a carbon aerogel network to act as the sinteringmore » aid for B 4C. Finally, due to the highly effective distribution of in situ carbon for the B 4C matrix, near-full sintered density of 97–98% of theoretical maximum density was achieved.« less

  9. Metrological assurance and traceability for Industry 4.0 and additive manufacturing in Ukraine

    NASA Astrophysics Data System (ADS)

    Skliarov, Volodymyr; Neyezhmakov, Pavel; Prokopov, Alexander

    2018-03-01

    The national measurement standards from the point of view of traceability of the results of measurement in additive manufacturing in Ukraine are considered in the paper. The metrological characteristics of the national primary measurement standards in the field of geometric, temperature, optical-physical and time-frequency measurements, which took part in international comparisons within COOMET projects, are presented. The accurate geometric, temperature, optical-physical and time-frequency measurements are the key ones in controlling the quality of additive manufacturing. The use of advanced CAD/CAE/CAM systems allows to simulate the process of additive manufacturing at each stage. In accordance with the areas of the technology of additive manufacturing, the ways of improving the national measurement standards of Ukraine for the growing needs of metrology of additive manufacturing are considered.

  10. Evaluation of microstructure stability at the interfaces of Al-6061 welds fabricated using ultrasonic additive manufacturing

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sridharan, Niyanth S.; Gussev, Maxim N.; Parish, Chad M.

    Here, ultrasonic additive manufacturing (UAM) is a solid-state additive manufacturing process that uses fundamental principles of ultrasonic welding and sequential layering of tapes to fabricate complex three-dimensional (3-D) components. One of the factors limiting the use of this technology is the poor tensile strength along the z-axis. Recent work has demonstrated the improvement of the z-axis properties after post-processing treatments. The abnormally high stability of the grains at the interface during post-weld heat treatments is, however, not yet well understood. In this work we use multiscale characterization to understand the stability of the grains during post-weld heat treatments. Aluminum alloymore » (6061) builds, fabricated using ultrasonic additive manufacturing, were post-weld heat treated at 180, 330 and 580 °C. The grains close to the tape interfaces are stable during post-weld heat treatments at high temperatures (i.e., 580 °C). This is in contrast to rapid grain growth that takes place in the bulk. Transmission electron microscopy and atom-probe tomography display a significant enrichment of oxygen and magnesium near the stable interfaces. Based on the detailed characterization, two mechanisms are proposed and evaluated: nonequilibrium nano-dispersed oxides impeding the grain growth due to grain boundary pinning, or grain boundary segregation of magnesium and oxygen reducing the grain boundary energy.« less

  11. Evaluation of microstructure stability at the interfaces of Al-6061 welds fabricated using ultrasonic additive manufacturing

    DOE PAGES

    Sridharan, Niyanth S.; Gussev, Maxim N.; Parish, Chad M.; ...

    2018-03-06

    Here, ultrasonic additive manufacturing (UAM) is a solid-state additive manufacturing process that uses fundamental principles of ultrasonic welding and sequential layering of tapes to fabricate complex three-dimensional (3-D) components. One of the factors limiting the use of this technology is the poor tensile strength along the z-axis. Recent work has demonstrated the improvement of the z-axis properties after post-processing treatments. The abnormally high stability of the grains at the interface during post-weld heat treatments is, however, not yet well understood. In this work we use multiscale characterization to understand the stability of the grains during post-weld heat treatments. Aluminum alloymore » (6061) builds, fabricated using ultrasonic additive manufacturing, were post-weld heat treated at 180, 330 and 580 °C. The grains close to the tape interfaces are stable during post-weld heat treatments at high temperatures (i.e., 580 °C). This is in contrast to rapid grain growth that takes place in the bulk. Transmission electron microscopy and atom-probe tomography display a significant enrichment of oxygen and magnesium near the stable interfaces. Based on the detailed characterization, two mechanisms are proposed and evaluated: nonequilibrium nano-dispersed oxides impeding the grain growth due to grain boundary pinning, or grain boundary segregation of magnesium and oxygen reducing the grain boundary energy.« less

  12. High-Speed Additive Manufacturing Through High-Aspect-Ratio Nozzles

    NASA Astrophysics Data System (ADS)

    Shaw, Leon; Islam, Mashfiqul; Li, Jie; Li, Ling; Ayub, S. M. Imran

    2018-03-01

    The feasibility of layer-by-layer manufacturing through high-aspect-ratio (HAR) nozzles for microextrusion of paste to deposit planes has been investigated. Various conditions for paste extrusion, including nozzle moving speed, piston speed, extrusion rate, and distance between the nozzle tip and substrate, have been evaluated. By linking various microextrusion parameters together with the aid of a critical distance concept derived from microextrusion using circular nozzles and addressing the extrusion delay in response to the change of the piston speed and air pocket problems properly, we successfully microextruded single planes, multilayer objects, and larger planes made of multiple smaller planes side by side through HAR nozzles. It is further demonstrated that the X- Y dimensions of an extruded plane in the steady-state extrusion stage are determined by the nozzle travel distance and the length of the HAR nozzle opening if microextrusion is conducted with proper conditions. However, the height of the extruded plane is not only determined by the microextrusion conditions, but also affected by the drying shrinkage of the paste after microextrusion. This demonstration of the feasibility of using a HAR nozzle machine opens the door to manufacture of multimaterial, multilayer devices with high productivity in the near future.

  13. Investigation of plasma arc welding as a method for the additive manufacturing of titanium-(6)aluminum-(4)vanadium alloy components

    NASA Astrophysics Data System (ADS)

    Stavinoha, Joe N.

    The process of producing near net-shape components by material deposition is known as additive manufacturing. All additive manufacturing processes are based on the addition of material with the main driving forces being cost reduction and flexibility in both manufacturing and product design. With wire metal deposition, metal is deposited as beads side-by-side and layer-by-layer in a desired pattern to build a complete component or add features on a part. There are minimal waste products, low consumables, and an efficient use of energy and feedstock associated with additive manufacturing processes. Titanium and titanium alloys are useful engineering materials that possess an extraordinary combination of properties. Some of the properties that make titanium advantageous for structural applications are its high strength-to-weight ratio, low density, low coefficient of thermal expansion, and good corrosion resistance. The most commonly used titanium alloy, Ti-6Al-4V, is typically used in aerospace applications, pressure vessels, aircraft gas turbine disks, cases and compressor blades, and surgical implants. Because of the high material prices associated with titanium alloys, the production of near net-shape components by additive manufacturing is an attractive option for the manufacturing of Ti-6Al-4V alloy components. In this thesis, the manufacturing of cylindrical Ti-6Al-4V alloy specimens by wire metal deposition utilizing the plasma arc welding process was demonstrated. Plasma arc welding is a cost effective additive manufacturing technique when compared to other current additive manufacturing methods such as laser beam welding and electron beam welding. Plasma arc welding is considered a high-energy-density welding processes which is desirable for the successful welding of titanium. Metal deposition was performed using a constant current plasma arc welding power supply, flow-purged welding chamber, argon shielding and orifice gas, ERTi-5 filler metal, and Ti-6Al

  14. 22 CFR 124.9 - Additional clauses required only in manufacturing license agreements.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... manufacturing license agreements. 124.9 Section 124.9 Foreign Relations DEPARTMENT OF STATE INTERNATIONAL... Additional clauses required only in manufacturing license agreements. (a) Clauses for all manufacturing license agreements. The following clauses must be included only in manufacturing license agreements: (1...

  15. Additive Manufacturing: From Rapid Prototyping to Flight

    NASA Technical Reports Server (NTRS)

    Prater, Tracie

    2015-01-01

    Additive manufacturing (AM) offers tremendous promise for the rocket propulsion community. Foundational work must be performed to ensure the safe performance of AM parts. Government, industry, and academia must collaborate in the characterization, design, modeling, and process control to accelerate the certification of AM parts for human-rated flight.

  16. Feedstock powder processing research needs for additive manufacturing development

    DOE PAGES

    Anderson, Iver E.; White, Emma M. H.; Dehoff, Ryan

    2018-02-01

    Additive manufacturing (AM) promises to redesign traditional manufacturing by enabling the ultimate in agility for rapid component design changes in commercial products and for fabricating complex integrated parts. Here, by significantly increasing quality and yield of metallic alloy powders, the pace for design, development, and deployment of the most promising AM approaches can be greatly accelerated, resulting in rapid commercialization of these advanced manufacturing methods. By successful completion of a critical suite of processing research tasks that are intended to greatly enhance gas atomized powder quality and the precision and efficiency of powder production, researchers can help promote continued rapidmore » growth of AM. Finally, other powder-based or spray-based advanced manufacturing methods could also benefit from these research outcomes, promoting the next wave of sustainable manufacturing technologies for conventional and advanced materials.« less

  17. Feedstock powder processing research needs for additive manufacturing development

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Anderson, Iver E.; White, Emma M. H.; Dehoff, Ryan

    Additive manufacturing (AM) promises to redesign traditional manufacturing by enabling the ultimate in agility for rapid component design changes in commercial products and for fabricating complex integrated parts. Here, by significantly increasing quality and yield of metallic alloy powders, the pace for design, development, and deployment of the most promising AM approaches can be greatly accelerated, resulting in rapid commercialization of these advanced manufacturing methods. By successful completion of a critical suite of processing research tasks that are intended to greatly enhance gas atomized powder quality and the precision and efficiency of powder production, researchers can help promote continued rapidmore » growth of AM. Finally, other powder-based or spray-based advanced manufacturing methods could also benefit from these research outcomes, promoting the next wave of sustainable manufacturing technologies for conventional and advanced materials.« less

  18. Mechanical properties of additively manufactured octagonal honeycombs.

    PubMed

    Hedayati, R; Sadighi, M; Mohammadi-Aghdam, M; Zadpoor, A A

    2016-12-01

    Honeycomb structures have found numerous applications as structural and biomedical materials due to their favourable properties such as low weight, high stiffness, and porosity. Application of additive manufacturing and 3D printing techniques allows for manufacturing of honeycombs with arbitrary shape and wall thickness, opening the way for optimizing the mechanical and physical properties for specific applications. In this study, the mechanical properties of honeycomb structures with a new geometry, called octagonal honeycomb, were investigated using analytical, numerical, and experimental approaches. An additive manufacturing technique, namely fused deposition modelling, was used to fabricate the honeycomb from polylactic acid (PLA). The honeycombs structures were then mechanically tested under compression and the mechanical properties of the structures were determined. In addition, the Euler-Bernoulli and Timoshenko beam theories were used for deriving analytical relationships for elastic modulus, yield stress, Poisson's ratio, and buckling stress of this new design of honeycomb structures. Finite element models were also created to analyse the mechanical behaviour of the honeycombs computationally. The analytical solutions obtained using Timoshenko beam theory were close to computational results in terms of elastic modulus, Poisson's ratio and yield stress, especially for relative densities smaller than 25%. The analytical solutions based on the Timoshenko analytical solution and the computational results were in good agreement with experimental observations. Finally, the elastic properties of the proposed honeycomb structure were compared to those of other honeycomb structures such as square, triangular, hexagonal, mixed, diamond, and Kagome. The octagonal honeycomb showed yield stress and elastic modulus values very close to those of regular hexagonal honeycombs and lower than the other considered honeycombs. Copyright © 2016 Elsevier B.V. All rights

  19. Additive Manufacturing as a Sustainment Enabler: An Industry Perspective

    DTIC Science & Technology

    2016-12-01

    30 years with early emphasis and continued usage primarily during design and manufacturing of new systems. However, AM recently received increased...of newly designed AM-produced com- ponents into planned modifications and upgrades is an additional post- production opportunity funded by... manufacturing technology applications to the post- production stage. Putting together the solution relies on technical data management, applica- tion

  20. Additive manufacturing of permanent magnets

    DOE PAGES

    Paranthaman, M. P.; Nlebedim, I. C.; Johnson, F.; ...

    2016-10-28

    Here, permanent magnets enable energy conversion. Motors and generators are used to convert both electrical to mechanical energy and mechanical to electrical energy, respectively. They are precharged (magnetized) prior to being used in an application and must remain magnetized during operation. In addition, they should generate sufficient magnetic flux for a given application. Nevertheless permanent magnets can be demagnetized (discharged of their magnetization) by other magnetic materials in their service vicinity, temperature changes (thermal demagnetization), microstructural degradations and the magnet’s internal demagnetizing field. Therefore a permanent magnet can be qualified based on the properties that measure its ability to withstandmore » demagnetization and to supply sufficient magnetic flux required for a given application. Some of those properties are further discussed below. Additive manufacturing followed by exchange spring magnets will be discussed afterwards.« less

  1. New Nomenclatures for Heat Treatments of Additively Manufactured Titanium Alloys

    NASA Astrophysics Data System (ADS)

    Baker, Andrew H.; Collins, Peter C.; Williams, James C.

    2017-07-01

    The heat-treatment designations and microstructure nomenclatures for many structural metallic alloys were established for traditional metals processing, such as casting, hot rolling or forging. These terms do not necessarily apply for additively manufactured (i.e., three-dimensionally printed or "3D printed") metallic structures. The heat-treatment terminology for titanium alloys generally implies the heat-treatment temperatures and their sequence relative to a thermomechanical processing step (e.g., forging, rolling). These designations include: β-processing, α + β-processing, β-annealing, duplex annealing and mill annealing. Owing to the absence of a thermomechanical processing step, these traditional designations can pose a problem when titanium alloys are first produced via additive manufacturing, and then heat-treated. This communication proposes new nomenclatures for heat treatments of additively manufactured titanium alloys, and uses the distinct microstructural features to provide a correlation between traditional nomenclature and the proposed nomenclature.

  2. Additive manufacturing of biologically-inspired materials.

    PubMed

    Studart, André R

    2016-01-21

    Additive manufacturing (AM) technologies offer an attractive pathway towards the fabrication of functional materials featuring complex heterogeneous architectures inspired by biological systems. In this paper, recent research on the use of AM approaches to program the local chemical composition, structure and properties of biologically-inspired materials is reviewed. A variety of structural motifs found in biological composites have been successfully emulated in synthetic systems using inkjet-based, direct-writing, stereolithography and slip casting technologies. The replication in synthetic systems of design principles underlying such structural motifs has enabled the fabrication of lightweight cellular materials, strong and tough composites, soft robots and autonomously shaping structures with unprecedented properties and functionalities. Pushing the current limits of AM technologies in future research should bring us closer to the manufacturing capabilities of living organisms, opening the way for the digital fabrication of advanced materials with superior performance, lower environmental impact and new functionalities.

  3. Printability of alloys for additive manufacturing

    DOE PAGES

    Mukherjee, T.; Zuback, J. S.; De, A.; ...

    2016-01-22

    Although additive manufacturing (AM), or three dimensional (3D) printing, provides significant advantages over existing manufacturing techniques, metallic parts produced by AM are susceptible to distortion, lack of fusion defects and compositional changes. Here we show that the printability, or the ability of an alloy to avoid these defects, can be examined by developing and testing appropriate theories. A theoretical scaling analysis is used to test vulnerability of various alloys to thermal distortion. A theoretical kinetic model is used to examine predisposition of different alloys to AM induced compositional changes. A well-tested numerical heat transfer and fluid flow model is usedmore » to compare susceptibilities of various alloys to lack of fusion defects. These results are tested and validated with independent experimental data. Here, the findings presented in this paper are aimed at achieving distortion free, compositionally sound and well bonded metallic parts.« less

  4. Printability of alloys for additive manufacturing

    PubMed Central

    Mukherjee, T.; Zuback, J. S.; De, A.; DebRoy, T.

    2016-01-01

    Although additive manufacturing (AM), or three dimensional (3D) printing, provides significant advantages over existing manufacturing techniques, metallic parts produced by AM are susceptible to distortion, lack of fusion defects and compositional changes. Here we show that the printability, or the ability of an alloy to avoid these defects, can be examined by developing and testing appropriate theories. A theoretical scaling analysis is used to test vulnerability of various alloys to thermal distortion. A theoretical kinetic model is used to examine predisposition of different alloys to AM induced compositional changes. A well-tested numerical heat transfer and fluid flow model is used to compare susceptibilities of various alloys to lack of fusion defects. These results are tested and validated with independent experimental data. The findings presented in this paper are aimed at achieving distortion free, compositionally sound and well bonded metallic parts. PMID:26796864

  5. The specification of personalised insoles using additive manufacturing.

    PubMed

    Salles, André S; Gyi, Diane E

    2012-01-01

    Research has been conducted to explore a process that delivers insoles for personalised footwear for the high street using additive manufacturing (AM) and to evaluate the use of such insoles in terms of discomfort. Therefore, the footwear personalisation process was first identified: (1) foot capture; (2) anthropometric measurements; (3) insole design; and (4) additive manufacturing. In order to explore and evaluate this process, recreational runners were recruited. They had both feet scanned and 15 anthropometric measurements taken. Personalised insoles were designed from the scans and manufactured using AM. Participants were fitted with footwear under two experimental conditions: personalised and control, which were compared in terms of discomfort. The mean ratings for discomfort variables were generally low for both conditions and no significant differences were detected between conditions. In general, the personalisation process showed promise in terms of the scan data, although the foot capture position may not be considered 'gold standard'. Polyamide, the material used for the insoles, demonstrated positive attributes: visual inspection revealed no signs of breaking. The footwear personalisation process described and explored in this study shows potential and can be considered a good starting point for designer and researchers.

  6. The fracture and fragmentation behaviour of additively manufactured stainless steel 316L

    NASA Astrophysics Data System (ADS)

    Amott, Russell; Harris, Ernest; Winter, Ron; Stirk, Stewart; Chapman, David; Eakins, Daniel

    2015-06-01

    Expanding cylinder experiments using a gas gun technique allow investigations into the ductility of metals and the fracture and fragmentation mechanisms that occur during rapid tensile failure. These experiments allow the radial strain-rate of the expansion to be varied in the range 102 to 104 s-1. Presented here is a comparative study of the fracture and fragmentation behaviour of rapidly expanded stainless steel 316L cylinders manufactured from either wrought bar or by additive manufacturing techniques. The results show that in the strain-rate regime studied, an additively manufactured cylinder failed at a higher strain and produced larger fragment widths compared to cylinders manufactured from wrought bar. In addition, an investigation into the role of deliberate equispaced macroscopic voids introduced into a cylinder wall has been undertaken. Using the unique properties of additive manufacture, elongated voids were introduced to the cylinder wall at an angle of 45° to the cylinder radius, and the resulting fragment patterns will be discussed. A comparison of the expanding cylinder profiles with simulations using CTH will also be presented.

  7. Nondestructive Evaluation of Additive Manufacturing State-of-the-Discipline Report

    NASA Technical Reports Server (NTRS)

    Waller, Jess M.; Parker, Bradford H.; Hodges, Kenneth L.; Burke, Eric R.; Walker, James L.

    2014-01-01

    This report summarizes the National Aeronautics and Space Administrations (NASA) state of the art of nondestructive evaluation (NDE) for additive manufacturing (AM), or "3-D printed", hardware. NASA's unique need for highly customized spacecraft and instrumentation is suited for AM, which offers a compelling alternative to traditional subtractive manufacturing approaches. The Agency has an opportunity to push the envelope on how this technology is used in zero gravity, an enable in-space manufacturing of flight spares and replacement hardware crucial for long-duration, manned missions to Mars. The Agency is leveraging AM technology developed internally and by industry, academia, and other government agencies for its unique needs. Recent technical interchange meetings and workshops attended by NASA have identified NDE as a universal need for all aspects of additive manufacturing. The impact of NDE on AM is cross cutting and spans materials, processing quality assurance, testing and modeling disciplines. Appropriate NDE methods are needed before, during, and after the AM production process.

  8. The Use of Additive Manufacturing for Fabrication of Multi-Function Small Satellite Structures

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Horais, Brian J; Love, Lonnie J; Dehoff, Ryan R

    2013-01-01

    The use of small satellites in constellations is limited only by the growing functionality of smallsats themselves. Additive manufacturing provides exciting new design opportunities for development of multifunction CubeSat structures that integrate such functions as propulsion and thermal control into the satellite structures themselves. Manufacturing of these complex multifunction structures is now possible in lightweight, high strength, materials such as titanium by using existing electron beam melting additive manufacturing processes. However, the use of today's additive manufacturing capabilities is often cost-prohibitive for small companies due to the large capital investments required. To alleviate this impediment the U.S. Department of Energymore » has established a Manufacturing Demonstration Facility (MDF) at their Oak Ridge National Laboratory (ORNL) in Tennessee that provides industry access to a broad range of energy-efficient additive manufacturing equipment for collaborative use by both small and large organizations. This paper presents a notional CubeSat multifunction design that integrates the propulsion system into a three-unit (3U) CubeSat structure. The full-scale structure has been designed and fabricated at the ORNL MDF. The use of additive manufacturing for spacecraft fabrication is opening up many new possibilities in design and fabrication capabilities for what had previously been impossible structures to fabricate.« less

  9. Multi-orifice deposition nozzle for additive manufacturing

    DOEpatents

    Lind, Randall F.; Post, Brian K.; Cini, Colin L.

    2017-11-21

    An additive manufacturing extrusion head includes a nozzle for accepting and depositing a heated material onto a work surface and/or part. The nozzle includes a valve body and an internal poppet body moveable between positions to permit deposition of at least two bead sizes of heated material onto a work surface and/or part.

  10. Additively manufactured hierarchical stainless steels with high strength and ductility.

    PubMed

    Wang, Y Morris; Voisin, Thomas; McKeown, Joseph T; Ye, Jianchao; Calta, Nicholas P; Li, Zan; Zeng, Zhi; Zhang, Yin; Chen, Wen; Roehling, Tien Tran; Ott, Ryan T; Santala, Melissa K; Depond, Philip J; Matthews, Manyalibo J; Hamza, Alex V; Zhu, Ting

    2018-01-01

    Many traditional approaches for strengthening steels typically come at the expense of useful ductility, a dilemma known as strength-ductility trade-off. New metallurgical processing might offer the possibility of overcoming this. Here we report that austenitic 316L stainless steels additively manufactured via a laser powder-bed-fusion technique exhibit a combination of yield strength and tensile ductility that surpasses that of conventional 316L steels. High strength is attributed to solidification-enabled cellular structures, low-angle grain boundaries, and dislocations formed during manufacturing, while high uniform elongation correlates to a steady and progressive work-hardening mechanism regulated by a hierarchically heterogeneous microstructure, with length scales spanning nearly six orders of magnitude. In addition, solute segregation along cellular walls and low-angle grain boundaries can enhance dislocation pinning and promote twinning. This work demonstrates the potential of additive manufacturing to create alloys with unique microstructures and high performance for structural applications.

  11. Additively manufactured hierarchical stainless steels with high strength and ductility

    NASA Astrophysics Data System (ADS)

    Wang, Y. Morris; Voisin, Thomas; McKeown, Joseph T.; Ye, Jianchao; Calta, Nicholas P.; Li, Zan; Zeng, Zhi; Zhang, Yin; Chen, Wen; Roehling, Tien Tran; Ott, Ryan T.; Santala, Melissa K.; Depond, Philip J.; Matthews, Manyalibo J.; Hamza, Alex V.; Zhu, Ting

    2018-01-01

    Many traditional approaches for strengthening steels typically come at the expense of useful ductility, a dilemma known as strength-ductility trade-off. New metallurgical processing might offer the possibility of overcoming this. Here we report that austenitic 316L stainless steels additively manufactured via a laser powder-bed-fusion technique exhibit a combination of yield strength and tensile ductility that surpasses that of conventional 316L steels. High strength is attributed to solidification-enabled cellular structures, low-angle grain boundaries, and dislocations formed during manufacturing, while high uniform elongation correlates to a steady and progressive work-hardening mechanism regulated by a hierarchically heterogeneous microstructure, with length scales spanning nearly six orders of magnitude. In addition, solute segregation along cellular walls and low-angle grain boundaries can enhance dislocation pinning and promote twinning. This work demonstrates the potential of additive manufacturing to create alloys with unique microstructures and high performance for structural applications.

  12. Additively manufactured hierarchical stainless steels with high strength and ductility

    DOE PAGES

    Wang, Y. Morris; Voisin, Thomas; McKeown, Joseph T.; ...

    2017-10-30

    Many traditional approaches for strengthening steels typically come at the expense of useful ductility, a dilemma known as strength–ductility trade-off. New metallurgical processing might offer the possibility of overcoming this. Here we report that austenitic 316L stainless steels additively manufactured via a laser powder-bed-fusion technique exhibit a combination of yield strength and tensile ductility that surpasses that of conventional 316L steels. High strength is attributed to solidification-enabled cellular structures, low-angle grain boundaries, and dislocations formed during manufacturing, while high uniform elongation correlates to a steady and progressive work-hardening mechanism regulated by a hierarchically heterogeneous microstructure, with length scales spanning nearlymore » six orders of magnitude. In addition, solute segregation along cellular walls and low-angle grain boundaries can enhance dislocation pinning and promote twinning. This work demonstrates the potential of additive manufacturing to create alloys with unique microstructures and high performance for structural applications.« less

  13. Additively manufactured hierarchical stainless steels with high strength and ductility

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wang, Y. Morris; Voisin, Thomas; McKeown, Joseph T.

    Many traditional approaches for strengthening steels typically come at the expense of useful ductility, a dilemma known as strength–ductility trade-off. New metallurgical processing might offer the possibility of overcoming this. Here we report that austenitic 316L stainless steels additively manufactured via a laser powder-bed-fusion technique exhibit a combination of yield strength and tensile ductility that surpasses that of conventional 316L steels. High strength is attributed to solidification-enabled cellular structures, low-angle grain boundaries, and dislocations formed during manufacturing, while high uniform elongation correlates to a steady and progressive work-hardening mechanism regulated by a hierarchically heterogeneous microstructure, with length scales spanning nearlymore » six orders of magnitude. In addition, solute segregation along cellular walls and low-angle grain boundaries can enhance dislocation pinning and promote twinning. This work demonstrates the potential of additive manufacturing to create alloys with unique microstructures and high performance for structural applications.« less

  14. Additive Manufacturing of Functional Elements on Sheet Metal

    NASA Astrophysics Data System (ADS)

    Schaub, Adam; Ahuja, Bhrigu; Butzhammer, Lorenz; Osterziel, Johannes; Schmidt, Michael; Merklein, Marion

    Laser Beam Melting (LBM) process with its advantages of high design flexibility and free form manufacturing methodology is often applied limitedly due to its low productivity and unsuitability for mass production compared to conventional manufacturing processes. In order to overcome these limitations, a hybrid manufacturing methodology is developed combining the additive manufacturing process of laser beam melting with sheet forming processes. With an interest towards aerospace and medical industry, the material in focus is Ti-6Al-4V. Although Ti-6Al-4V is a commercially established material and its application for LBM process has been extensively investigated, the combination of LBM of Ti-6Al-4V with sheet metal still needs to be researched. Process dynamics such as high temperature gradients and thermally induced stresses lead to complex stress states at the interaction zone between the sheet and LBM structure. Within the presented paper mechanical characterization of hybrid parts will be performed by shear testing. The association of shear strength with process parameters is further investigated by analyzing the internal structure of the hybrid geometry at varying energy inputs during the LBM process. In order to compare the hybrid manufacturing methodology with conventional fabrication, the conventional methodologies subtractive machining and state of the art Laser Beam Melting is evaluated within this work. These processes will be analyzed for their mechanical characteristics and productivity by determining the build time and raw material consumption for each case. The paper is concluded by presenting the characteristics of the hybrid manufacturing methodology compared to alternative manufacturing technologies.

  15. Dielectric breakdown of additively manufactured polymeric materials

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Monzel, W. Jacob; Hoff, Brad W.; Maestas, Sabrina S.

    Dielectric strength testing of selected Polyjet-printed polymer plastics was performed in accordance with ASTM D149. This dielectric strength data is compared to manufacturer-provided dielectric strength data for selected plastics printed using the stereolithography (SLA), fused deposition modeling (FDM), and selective laser sintering (SLS) methods. Tested Polyjet samples demonstrated dielectric strengths as high as 47.5 kV/mm for a 0.5 mm thick sample and 32.1 kV/mm for a 1.0 mm sample. As a result, the dielectric strength of the additively manufactured plastics evaluated as part of this study was lower than the majority of non-printed plastics by at least 15% (with themore » exception of polycarbonate).« less

  16. Dielectric breakdown of additively manufactured polymeric materials

    DOE PAGES

    Monzel, W. Jacob; Hoff, Brad W.; Maestas, Sabrina S.; ...

    2016-01-11

    Dielectric strength testing of selected Polyjet-printed polymer plastics was performed in accordance with ASTM D149. This dielectric strength data is compared to manufacturer-provided dielectric strength data for selected plastics printed using the stereolithography (SLA), fused deposition modeling (FDM), and selective laser sintering (SLS) methods. Tested Polyjet samples demonstrated dielectric strengths as high as 47.5 kV/mm for a 0.5 mm thick sample and 32.1 kV/mm for a 1.0 mm sample. As a result, the dielectric strength of the additively manufactured plastics evaluated as part of this study was lower than the majority of non-printed plastics by at least 15% (with themore » exception of polycarbonate).« less

  17. Additive Manufacturing of Porous Metal

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dehoff, Ryan R.; Kirka, Michael M.

    2017-06-01

    Currently, helium is obtained through separation from natural gas. The current industrial process incurs significant costs and requires large energy resources to successfully achieve separation. Through utilizing Additive Manufacturing (AM) technologies it is possible to reduce both of these burdens when refining helium gas. The ability to engineer porosity levels within Inconel 718 discs for controlled separation of helium from natural gas was investigated. Arrays of samples fabricated using the electron beam melting process were analyzed for their relative porosity density. Based upon the measurements, full scale discs were fabricated, and subsequently tested to determine their effectiveness in separating heliummore » from liquefied natural gas.« less

  18. Additive Manufacturing of Cranial Simulants for Blast Induced Traumatic Brain Injury

    DTIC Science & Technology

    2017-08-28

    REPORT TYPE 08/28/2017 Poster 4. TITLE AND SUBTITLE Additive Manufacturing of Cranial Sin1ulants for Blast Induced Traumatic Brain Injut’y 6... manufacturing techniques: Fused deposition modeling: ca sling molds Casting: white and gray matter Polymerization of injected solution...Sandia National Laboratories Conclusion MICHIGAN STAT[ l- I’ll I \\ I R <, I r \\ Additive manufacturrng provrdes a cost effective fabrration

  19. High Fidelity Additive Manufacturing of Optically Transparent Glass Structures

    NASA Astrophysics Data System (ADS)

    Inamura, Chikara

    Glass has been an integral part of human civilization with expressions across scales and disciplines: from the microscope to the telescope, from fiber optics to mobile interface, and from the petri dish to a building envelope. Such a diverse range of applications is enabled by the inherent material properties including mechanical strength, optical transparency and chemical inertness. Additive manufacturing provides opportunities for integrating the unique properties of glass to engineer novel structures that are functionary graded through precise spatiotemporal deposition of molten glass. This talk presents the Mediated Matter Group's latest development of a novel additive manufacturing platform, and related processes, for 3D Printing optically transparent glass for architectural scale applications.

  20. Characterization of plastic and boron carbide additive manufactured neutron collimators

    NASA Astrophysics Data System (ADS)

    Stone, M. B.; Siddel, D. H.; Elliott, A. M.; Anderson, D.; Abernathy, D. L.

    2017-12-01

    Additive manufacturing techniques allow for the production of materials with complicated geometries with reduced costs and production time over traditional methods. We have applied this technique to the production of neutron collimators for use in thermal and cold neutron scattering instrumentation directly out of boron carbide. We discuss the design and generation of these collimators. We also provide measurements at neutron scattering beamlines which serve to characterize the performance of these collimators. Additive manufacturing of parts using neutron absorbing material may also find applications in radiography and neutron moderation.

  1. Additive direct-write microfabrication for MEMS: A review

    NASA Astrophysics Data System (ADS)

    Teh, Kwok Siong

    2017-12-01

    Direct-write additive manufacturing refers to a rich and growing repertoire of well-established fabrication techniques that builds solid objects directly from computer- generated solid models without elaborate intermediate fabrication steps. At the macroscale, direct-write techniques such as stereolithography, selective laser sintering, fused deposition modeling ink-jet printing, and laminated object manufacturing have significantly reduced concept-to-product lead time, enabled complex geometries, and importantly, has led to the renaissance in fabrication known as the maker movement. The technological premises of all direct-write additive manufacturing are identical—converting computer generated three-dimensional models into layers of two-dimensional planes or slices, which are then reconstructed sequentially into threedimensional solid objects in a layer-by-layer format. The key differences between the various additive manufacturing techniques are the means of creating the finished layers and the ancillary processes that accompany them. While still at its infancy, direct-write additive manufacturing techniques at the microscale have the potential to significantly lower the barrier-of-entry—in terms of cost, time and training—for the prototyping and fabrication of MEMS parts that have larger dimensions, high aspect ratios, and complex shapes. In recent years, significant advancements in materials chemistry, laser technology, heat and fluid modeling, and control systems have enabled additive manufacturing to achieve higher resolutions at the micrometer and nanometer length scales to be a viable technology for MEMS fabrication. Compared to traditional MEMS processes that rely heavily on expensive equipment and time-consuming steps, direct-write additive manufacturing techniques allow for rapid design-to-prototype realization by limiting or circumventing the need for cleanrooms, photolithography and extensive training. With current direct-write additive

  2. Evaluation of Additive Manufacturing for Stainless Steel Components

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Peter, William H.; Lou, Xiaoyuan; List, III, Frederick Alyious

    This collaboration between Oak Ridge National Laboratory and General Electric Company aimed to evaluate the mechanical properties, microstructure, and porosity of the additively manufactured 316L stainless steel by ORNL’s Renishaw AM250 machine for nuclear application. The program also evaluated the stress corrosion cracking and corrosion fatigue crack growth rate of the same material in high temperature water environments. Results show the properties of this material to be similar to the properties of 316L stainless steel fabricated additively with equipment from other manufacturers with slightly higher porosity. The stress corrosion crack growth rate is similar to that for wrought 316L stainlessmore » steel for an oxygenated high temperature water environment and slightly higher for a hydrogenated high temperature water environment. Optimized heat treatment of this material is expected to improve performance in high temperature water environments.« less

  3. Application of Additive Manufacturing in Oral and Maxillofacial Surgery.

    PubMed

    Farré-Guasch, Elisabet; Wolff, Jan; Helder, Marco N; Schulten, Engelbert A J M; Forouzanfar, Tim; Klein-Nulend, Jenneke

    2015-12-01

    Additive manufacturing is the process of joining materials to create objects from digital 3-dimensional (3D) model data, which is a promising technology in oral and maxillofacial surgery. The management of lost craniofacial tissues owing to congenital abnormalities, trauma, or cancer treatment poses a challenge to oral and maxillofacial surgeons. Many strategies have been proposed for the management of such defects, but autogenous bone grafts remain the gold standard for reconstructive bone surgery. Nevertheless, cell-based treatments using adipose stem cells combined with osteoconductive biomaterials or scaffolds have become a promising alternative to autogenous bone grafts. Such treatment protocols often require customized 3D scaffolds that fulfill functional and esthetic requirements, provide adequate blood supply, and meet the load-bearing requirements of the head. Currently, such customized 3D scaffolds are being manufactured using additive manufacturing technology. In this review, 2 of the current and emerging modalities for reconstruction of oral and maxillofacial bone defects are highlighted and discussed, namely human maxillary sinus floor elevation as a valid model to test bone tissue-engineering approaches enabling the application of 1-step surgical procedures and seeding of Good Manufacturing Practice-level adipose stem cells on computer-aided manufactured scaffolds to reconstruct large bone defects in a 2-step surgical procedure, in which cells are expanded ex vivo and seeded on resorbable scaffolds before implantation. Furthermore, imaging-guided tissue-engineering technologies to predetermine the surgical location and to facilitate the manufacturing of custom-made implants that meet the specific patient's demands are discussed. The potential of tissue-engineered constructs designed for the repair of large oral and maxillofacial bone defects in load-bearing situations in a 1-step surgical procedure combining these 2 innovative approaches is

  4. Electrostatic Levitation for Studies of Additive Manufactured Materials

    NASA Technical Reports Server (NTRS)

    SanSoucie, Michael P.; Rogers, Jan R.; Tramel, Terri

    2014-01-01

    The electrostatic levitation (ESL) laboratory at NASA's Marshall Space Flight Center is a unique facility for investigators studying high temperature materials. The laboratory boasts two levitators in which samples can be levitated, heated, melted, undercooled, and resolidified. Electrostatic levitation minimizes gravitational effects and allows materials to be studied without contact with a container or instrumentation. The lab also has a high temperature emissivity measurement system, which provides normal spectral and normal total emissivity measurements at use temperature. The ESL lab has been instrumental in many pioneering materials investigations of thermophysical properties, e.g., creep measurements, solidification, triggered nucleation, and emissivity at high temperatures. Research in the ESL lab has already led to the development of advanced high temperature materials for aerospace applications, coatings for rocket nozzles, improved medical and industrial optics, metallic glasses, ablatives for reentry vehicles, and materials with memory. Modeling of additive manufacturing materials processing is necessary for the study of their resulting materials properties. In addition, the modeling of the selective laser melting processes and its materials property predictions are also underway. Unfortunately, there is very little data for the properties of these materials, especially of the materials in the liquid state. Some method to measure thermophysical properties of additive manufacturing materials is necessary. The ESL lab is ideal for these studies. The lab can provide surface tension and viscosity of molten materials, density measurements, emissivity measurements, and even creep strength measurements. The ESL lab can also determine melting temperature, surface temperatures, and phase transition temperatures of additive manufactured materials. This presentation will provide background on the ESL lab and its capabilities, provide an approach to using the ESL

  5. Summary of NDE of Additive Manufacturing Efforts in NASA

    NASA Technical Reports Server (NTRS)

    Waller, Jess; Saulsberry, Regor; Parker, Bradford; Hodges, Kenneth; Burke, Eric; Taminger, Karen

    2014-01-01

    (1) General Rationale for Additive Manufacturing (AM): (a) Operate under a 'design-to-constraint' paradigm, make parts too complicated to fabricate otherwise, (b) Reduce weight by 20 percent with monolithic parts, (c) Reduce waste (green manufacturing), (e) Eliminate reliance on Original Equipment Manufacturers for critical spares, and (f) Extend life of in-service parts by innovative repair methods; (2) NASA OSMA NDE of AM State-of-the-Discipline Report; (3) Overview of NASA AM Efforts at Various Centers: (a) Analytical Tools, (b) Ground-Based Fabrication (c) Space-Based Fabrication; and (d) Center Activity Summaries; (4) Overview of NASA NDE data to date on AM parts; and (5) Gap Analysis/Recommendations for NDE of AM.

  6. 3D Microstructural Architectures for Metal and Alloy Components Fabricated by 3D Printing/Additive Manufacturing Technologies

    NASA Astrophysics Data System (ADS)

    Martinez, E.; Murr, L. E.; Amato, K. N.; Hernandez, J.; Shindo, P. W.; Gaytan, S. M.; Ramirez, D. A.; Medina, F.; Wicker, R. B.

    The layer-by-layer building of monolithic, 3D metal components from selectively melted powder layers using laser or electron beams is a novel form of 3D printing or additive manufacturing. Microstructures created in these 3D products can involve novel, directional solidification structures which can include crystallographically oriented grains containing columnar arrays of precipitates characteristic of a microstructural architecture. These microstructural architectures are advantageously rendered in 3D image constructions involving light optical microscopy and scanning and transmission electron microscopy observations. Microstructural evolution can also be effectively examined through 3D image sequences which, along with x-ray diffraction (XRD) analysis in the x-y and x-z planes, can effectively characterize related crystallographic/texture variances. This paper compares 3D microstructural architectures in Co-base and Ni-base superalloys, columnar martensitic grain structures in 17-4 PH alloy, and columnar copper oxides and dislocation arrays in copper.

  7. Surface modification of biomaterials and biomedical devices using additive manufacturing.

    PubMed

    Bose, Susmita; Robertson, Samuel Ford; Bandyopadhyay, Amit

    2018-01-15

    The demand for synthetic biomaterials in medical devices, pharmaceutical products and, tissue replacement applications are growing steadily due to aging population worldwide. The use for patient matched devices is also increasing due to availability and integration of new technologies. Applications of additive manufacturing (AM) or 3D printing (3DP) in biomaterials have also increased significantly over the past decade towards traditional as well as innovative next generation Class I, II and III devices. In this review, we have focused our attention towards the use of AM in surface modified biomaterials to enhance their in vitro and in vivo performances. Specifically, we have discussed the use of AM to deliberately modify the surfaces of different classes of biomaterials with spatial specificity in a single manufacturing process as well as commented on the future outlook towards surface modification using AM. It is widely understood that the success of implanted medical devices depends largely on favorable material-tissue interactions. Additive manufacturing has gained traction as a viable and unique approach to engineered biomaterials, for both bulk and surface properties that improve implant outcomes. This review explores how additive manufacturing techniques have been and can be used to augment the surfaces of biomedical devices for direct clinical applications. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  8. Highly oriented carbon fiber–polymer composites via additive manufacturing

    DOE PAGES

    Tekinalp, Halil L.; Kunc, Vlastimil; Velez-Garcia, Gregorio M.; ...

    2014-10-16

    Additive manufacturing, diverging from traditional manufacturing techniques, such as casting and machining materials, can handle complex shapes with great design flexibility without the typical waste. Although this technique has been mainly used for rapid prototyping, interest is growing in using this method to directly manufacture actual parts of complex shape. To use 3D-printing additive manufacturing in wide spread applications, the technique and the feedstock materials require improvements to meet the mechanical requirements of load-bearing components. Thus, we investigated the short fiber (0.2 mm to 0.4 mm) reinforced acrylonitrile-butadiene-styrene composites as a feedstock for 3D-printing in terms of their processibility, microstructuremore » and mechanical performance; and also provided comparison with traditional compression molded composites. The tensile strength and modulus of 3D-printed samples increased ~115% and ~700%, respectively. 3D-printer yielded samples with very high fiber orientation in printing direction (up to 91.5 %), whereas, compression molding process yielded samples with significantly less fiber orientation. Microstructure-mechanical property relationships revealed that although the relatively high porosity is observed in the 3D-printed composites as compared to those produced by the conventional compression molding technique, they both exhibited comparable tensile strength and modulus. Furthermore, this phenomena is explained based on the changes in fiber orientation, dispersion and void formation.« less

  9. When America Makes, America Works A Successful Public Private 3D Printing (Additive Manufacturing) Partnership

    DTIC Science & Technology

    2016-10-01

    Additive Manufacturing ) Partnership Jennifer Fielding, Ph.D.  Ed Morris  Rob Gorham  Emily Fehrman Cory, Ph.D.  Scott Leonard Fielding is the...government partners for America Makes and other Manufacturing Innovation Institutes. America Makes is the National Additive Manufactur -ing Innovation Institute...vision for America Makes is to accelerate additive manufacturing (AM) inno-vation to enable widespread adoption by bridging the gap between basic

  10. 40 CFR 79.21 - Information and assurances to be provided by the additive manufacturer.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... provided by the additive manufacturer. 79.21 Section 79.21 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) REGISTRATION OF FUELS AND FUEL ADDITIVES Additive Registration Procedures § 79.21 Information and assurances to be provided by the additive manufacturer. Each...

  11. 40 CFR 79.21 - Information and assurances to be provided by the additive manufacturer.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... provided by the additive manufacturer. 79.21 Section 79.21 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) REGISTRATION OF FUELS AND FUEL ADDITIVES Additive Registration Procedures § 79.21 Information and assurances to be provided by the additive manufacturer. Each...

  12. 40 CFR 79.21 - Information and assurances to be provided by the additive manufacturer.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... provided by the additive manufacturer. 79.21 Section 79.21 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) REGISTRATION OF FUELS AND FUEL ADDITIVES Additive Registration Procedures § 79.21 Information and assurances to be provided by the additive manufacturer. Each...

  13. 40 CFR 79.21 - Information and assurances to be provided by the additive manufacturer.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... provided by the additive manufacturer. 79.21 Section 79.21 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) REGISTRATION OF FUELS AND FUEL ADDITIVES Additive Registration Procedures § 79.21 Information and assurances to be provided by the additive manufacturer. Each...

  14. 40 CFR 79.21 - Information and assurances to be provided by the additive manufacturer.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... provided by the additive manufacturer. 79.21 Section 79.21 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) REGISTRATION OF FUELS AND FUEL ADDITIVES Additive Registration Procedures § 79.21 Information and assurances to be provided by the additive manufacturer. Each...

  15. Effects of plasma electrolytic oxidation process on the mechanical properties of additively manufactured porous biomaterials.

    PubMed

    Gorgin Karaji, Zahra; Hedayati, Reza; Pouran, Behdad; Apachitei, Iulian; Zadpoor, Amir A

    2017-07-01

    Metallic porous biomaterials are recently attracting more attention thanks to the additive manufacturing techniques which help produce more complex structures as compared to conventional techniques. On the other hand, bio-functional surfaces on metallic biomaterials such as titanium and its alloys are necessary to enhance the biological interactions with the host tissue. This study discusses the effect of plasma electrolytic oxidation (PEO), as a surface modification technique to produce bio-functional layers, on the mechanical properties of additively manufactured Ti6Al4V scaffolds based on the cubic unit cell. For this purpose, the PEO process with two different oxidation times was applied on scaffolds with four different values of relative density. The effects of the PEO process were studied by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), optical microscopy as well as static and dynamic (fatigue) mechanical testing under compression. SEM results indicated pore formation on the surface of the scaffolds after oxidation with a thickness of 4.85±0.36μm of the oxide layer after 2min and 9.04±2.27μm after 5min oxidation (based on optical images). The static test results showed the high effect of relative density of porous structure on its mechanical properties. However, oxidation did not influence most of the mechanical properties such as maximum stress, yield stress, plateau stress, and energy absorption, although its effect on the elastic modulus was considerable. Under fatigue loading, none of the scaffolds failed even after 10 6 loading cycles at 70% of their yield stress. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Comparison of prosthetic models produced by traditional and additive manufacturing methods.

    PubMed

    Park, Jin-Young; Kim, Hae-Young; Kim, Ji-Hwan; Kim, Jae-Hong; Kim, Woong-Chul

    2015-08-01

    The purpose of this study was to verify the clinical-feasibility of additive manufacturing by comparing the accuracy of four different manufacturing methods for metal coping: the conventional lost wax technique (CLWT); subtractive methods with wax blank milling (WBM); and two additive methods, multi jet modeling (MJM), and micro-stereolithography (Micro-SLA). Thirty study models were created using an acrylic model with the maxillary upper right canine, first premolar, and first molar teeth. Based on the scan files from a non-contact blue light scanner (Identica; Medit Co. Ltd., Seoul, Korea), thirty cores were produced using the WBM, MJM, and Micro-SLA methods, respectively, and another thirty frameworks were produced using the CLWT method. To measure the marginal and internal gap, the silicone replica method was adopted, and the silicone images obtained were evaluated using a digital microscope (KH-7700; Hirox, Tokyo, Japan) at 140X magnification. Analyses were performed using two-way analysis of variance (ANOVA) and Tukey post hoc test (α=.05). The mean marginal gaps and internal gaps showed significant differences according to tooth type (P<.001 and P<.001, respectively) and manufacturing method (P<.037 and P<.001, respectively). Micro-SLA did not show any significant difference from CLWT regarding mean marginal gap compared to the WBM and MJM methods. The mean values of gaps resulting from the four different manufacturing methods were within a clinically allowable range, and, thus, the clinical use of additive manufacturing methods is acceptable as an alternative to the traditional lost wax-technique and subtractive manufacturing.

  17. Additively Manufactured and Surface Biofunctionalized Porous Nitinol.

    PubMed

    Gorgin Karaji, Z; Speirs, M; Dadbakhsh, S; Kruth, J-P; Weinans, H; Zadpoor, A A; Amin Yavari, S

    2017-01-18

    Enhanced bone tissue regeneration and improved osseointegration are among the most important goals in design of multifunctional orthopedic biomaterials. In this study, we used additive manufacturing (selective laser melting) to develop multifunctional porous nitinol that combines superelasticity with a rationally designed microarchitecture and biofunctionalized surface. The rational design based on triply periodic minimal surfaces aimed to properly adjust the pore size, increase the surface area (thereby amplifying the effects of surface biofunctionalization), and resemble the curvature characteristics of trabecular bone. The surface of additively manufactured (AM) porous nitinol was biofunctionalized using polydopamine-immobilized rhBMP2 for better control of the release kinetics. The actual morphological properties of porous nitinol measured by microcomputed tomography (e.g., open/close porosity, and surface area) closely matched the design values. The superelasticity originated from the austenite phase formed in the nitinol porous structure at room temperature. Polydopamine and rhBMP2 signature peaks were confirmed by X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy tests. The release of rhBMP2 continued until 28 days. The early time and long-term release profiles were found to be adjustable independent of each other. In vitro cell culture showed improved cell attachment, cell proliferation, cell morphology (spreading, spindle-like shape), and cell coverage as well as elevated levels of ALP activity and increased calcium content for biofunctionalized surfaces as compared to as-manufactured specimens. The demonstrated functionalities of porous nitinol could be used as a basis for deployable orthopedic implants with rationally designed microarchitectures that maximize bone tissue regeneration performance by release of biomolecules with adjustable and well-controlled release profiles.

  18. Demonstration of array eddy current technology for real-time monitoring of laser powder bed fusion additive manufacturing process

    NASA Astrophysics Data System (ADS)

    Todorov, Evgueni; Boulware, Paul; Gaah, Kingsley

    2018-03-01

    Nondestructive evaluation (NDE) at various fabrication stages is required to assure quality of feedstock and solid builds. Industry efforts are shifting towards solutions that can provide real-time monitoring of additive manufacturing (AM) fabrication process layer-by-layer while the component is being built to reduce or eliminate dependence on post-process inspection. Array eddy current (AEC), electromagnetic NDE technique was developed and implemented to directly scan the component without physical contact with the powder and fused layer surfaces at elevated temperatures inside a LPBF chamber. The technique can detect discontinuities, surface irregularities, and undesirable metallurgical phase transformations in magnetic and nonmagnetic conductive materials used for laser fusion. The AEC hardware and software were integrated with the L-PBF test bed. Two layer-by-layer tests of Inconel 625 coupons with AM built discontinuities and lack of fusion were conducted inside the L-PBF chamber. The AEC technology demonstrated excellent sensitivity to seeded, natural surface, and near-surface-embedded discontinuities, while also detecting surface topography. The data was acquired and imaged in a layer-by-layer sequence demonstrating the real-time monitoring capabilities of this new technology.

  19. Large-scale additive manufacturing with bioinspired cellulosic materials.

    PubMed

    Sanandiya, Naresh D; Vijay, Yadunund; Dimopoulou, Marina; Dritsas, Stylianos; Fernandez, Javier G

    2018-06-05

    Cellulose is the most abundant and broadly distributed organic compound and industrial by-product on Earth. However, despite decades of extensive research, the bottom-up use of cellulose to fabricate 3D objects is still plagued with problems that restrict its practical applications: derivatives with vast polluting effects, use in combination with plastics, lack of scalability and high production cost. Here we demonstrate the general use of cellulose to manufacture large 3D objects. Our approach diverges from the common association of cellulose with green plants and it is inspired by the wall of the fungus-like oomycetes, which is reproduced introducing small amounts of chitin between cellulose fibers. The resulting fungal-like adhesive material(s) (FLAM) are strong, lightweight and inexpensive, and can be molded or processed using woodworking techniques. We believe this first large-scale additive manufacture with ubiquitous biological polymers will be the catalyst for the transition to environmentally benign and circular manufacturing models.

  20. Feasibility and Scaling of Composite Based Additive Manufacturing

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Nuttall, David; Chen, Xun; Kunc, Vlastimil

    2016-04-27

    Engineers and Researchers at Oak Ridge National Lab s Manufacturing Demonstration Facility (ORNL MDF) collaborated with Impossible Objects (IO) in the characterization of PEEK infused carbon fiber mat manufactured by means of CBAM composite-based additive manufacturing, a first generation assembly methodology developed by Robert Swartz, Chairman, Founder, and CTO of Impossible Objects.[1] The first phase of this project focused on demonstration of CBAM for composite tooling. The outlined steps focused on selecting an appropriate shape that fit the current machine s build envelope, characterized the resulting form, and presented next steps for transitioning to a Phase II CRADA agreement. Phasemore » I of collaborative research and development agreement NFE-15-05698 was initiated in April of 2015 with an introduction to Impossible Objects, and concluded in March of 2016 with a visitation to Impossible Objects headquarters in Chicago, IL. Phase II as discussed herein is under consideration by Impossible Objects as of this writing.« less

  1. Neutron residual stress measurement and numerical modeling in a curved thin-walled structure by laser powder bed fusion additive manufacturing

    DOE PAGES

    An, Ke; Yuan, Lang; Dial, Laura; ...

    2017-09-11

    Severe residual stresses in metal parts made by laser powder bed fusion additive manufacturing processes (LPBFAM) can cause both distortion and cracking during the fabrication processes. Limited data is currently available for both iterating through process conditions and design, and in particular, for validating numerical models to accelerate process certification. In this work, residual stresses of a curved thin-walled structure, made of Ni-based superalloy Inconel 625™ and fabricated by LPBFAM, were resolved by neutron diffraction without measuring the stress-free lattices along both the build and the transverse directions. The stresses of the entire part during fabrication and after cooling downmore » were predicted by a simplified layer-by-layer finite element based numerical model. The simulated and measured stresses were found in good quantitative agreement. The validated simplified simulation methodology will allow to assess residual stresses in more complex structures and to significantly reduce manufacturing cycle time.« less

  2. Neutron residual stress measurement and numerical modeling in a curved thin-walled structure by laser powder bed fusion additive manufacturing

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    An, Ke; Yuan, Lang; Dial, Laura

    Severe residual stresses in metal parts made by laser powder bed fusion additive manufacturing processes (LPBFAM) can cause both distortion and cracking during the fabrication processes. Limited data is currently available for both iterating through process conditions and design, and in particular, for validating numerical models to accelerate process certification. In this work, residual stresses of a curved thin-walled structure, made of Ni-based superalloy Inconel 625™ and fabricated by LPBFAM, were resolved by neutron diffraction without measuring the stress-free lattices along both the build and the transverse directions. The stresses of the entire part during fabrication and after cooling downmore » were predicted by a simplified layer-by-layer finite element based numerical model. The simulated and measured stresses were found in good quantitative agreement. The validated simplified simulation methodology will allow to assess residual stresses in more complex structures and to significantly reduce manufacturing cycle time.« less

  3. Modeling of Processing-Induced Pore Morphology in an Additively-Manufactured Ti-6Al-4V Alloy

    PubMed Central

    Kabir, Mohammad Rizviul; Richter, Henning

    2017-01-01

    A selective laser melting (SLM)-based, additively-manufactured Ti-6Al-4V alloy is prone to the accumulation of undesirable defects during layer-by-layer material build-up. Defects in the form of complex-shaped pores are one of the critical issues that need to be considered during the processing of this alloy. Depending on the process parameters, pores with concave or convex boundaries may occur. To exploit the full potential of additively-manufactured Ti-6Al-4V, the interdependency between the process parameters, pore morphology, and resultant mechanical properties, needs to be understood. By incorporating morphological details into numerical models for micromechanical analyses, an in-depth understanding of how these pores interact with the Ti-6Al-4V microstructure can be gained. However, available models for pore analysis lack a realistic description of both the Ti-6Al-4V grain microstructure, and the pore geometry. To overcome this, we propose a comprehensive approach for modeling and discretizing pores with complex geometry, situated in a polycrystalline microstructure. In this approach, the polycrystalline microstructure is modeled by means of Voronoi tessellations, and the complex pore geometry is approximated by strategically combining overlapping spheres of varied sizes. The proposed approach provides an elegant way to model the microstructure of SLM-processed Ti-6Al-4V containing pores or crack-like voids, and makes it possible to investigate the relationship between process parameters, pore morphology, and resultant mechanical properties in a finite-element-based simulation framework. PMID:28772504

  4. Modeling of Processing-Induced Pore Morphology in an Additively-Manufactured Ti-6Al-4V Alloy.

    PubMed

    Kabir, Mohammad Rizviul; Richter, Henning

    2017-02-08

    A selective laser melting (SLM)-based, additively-manufactured Ti-6Al-4V alloy is prone to the accumulation of undesirable defects during layer-by-layer material build-up. Defects in the form of complex-shaped pores are one of the critical issues that need to be considered during the processing of this alloy. Depending on the process parameters, pores with concave or convex boundaries may occur. To exploit the full potential of additively-manufactured Ti-6Al-4V, the interdependency between the process parameters, pore morphology, and resultant mechanical properties, needs to be understood. By incorporating morphological details into numerical models for micromechanical analyses, an in-depth understanding of how these pores interact with the Ti-6Al-4V microstructure can be gained. However, available models for pore analysis lack a realistic description of both the Ti-6Al-4V grain microstructure, and the pore geometry. To overcome this, we propose a comprehensive approach for modeling and discretizing pores with complex geometry, situated in a polycrystalline microstructure. In this approach, the polycrystalline microstructure is modeled by means of Voronoi tessellations, and the complex pore geometry is approximated by strategically combining overlapping spheres of varied sizes. The proposed approach provides an elegant way to model the microstructure of SLM-processed Ti-6Al-4V containing pores or crack-like voids, and makes it possible to investigate the relationship between process parameters, pore morphology, and resultant mechanical properties in a finite-element-based simulation framework.

  5. Driving Innovation to Support the Warfighter: Additive Manufacturing Initiatives Within the Defense Logistics Agency

    DTIC Science & Technology

    2016-12-01

    43 Defense AT&L: November-December 2016 Driving Innovation to Support the Warfighter Additive Manufacturing Initiatives Within the Defense...Degree in National Resource Strategy from the Industrial College of the Armed Forces in Washington, D.C. T he spotlight is on for additive manufacturing ...and meet the warfighter’s needs” (see Figure 2). In order to “deliver additively manufactured solutions you can trust” (see Figure 2) in the DoD

  6. The fracture and fragmentation behaviour of additively manufactured stainless steel 316L

    NASA Astrophysics Data System (ADS)

    Amott, R.; Harris, E. J.; Winter, R. E.; Stirk, S. M.; Chapman, D. J.; Eakins, D. E.

    2017-01-01

    Expanding cylinder experiments using a gas gun technique allow investigations into the ductility of metals and the fracture and fragmentation mechanisms that occur during rapid tensile failure. These experiments allow the radial strain-rate of the expansion to be varied in the range 102 to 104 s-1. Presented here is a comparative study of the fracture and fragmentation behaviour of rapidly expanded stainless steel 316L cylinders manufactured from either a wrought bar or additive manufacturing techniques. The results show that in the strain-rate regime studied, an additively manufactured cylinder failed at a higher strain and produced larger fragment widths when compared to cylinders manufactured from a wrought bar. In addition, an investigation into the role of macroscopic elongated voids that were introduced into the cylinder wall, at an angle of 45° to the cylinder radius, was undertaken. A comparison between experimental and simulated results (using the Eulerian hydrocode CTH) was also completed.

  7. CT image segmentation methods for bone used in medical additive manufacturing.

    PubMed

    van Eijnatten, Maureen; van Dijk, Roelof; Dobbe, Johannes; Streekstra, Geert; Koivisto, Juha; Wolff, Jan

    2018-01-01

    The accuracy of additive manufactured medical constructs is limited by errors introduced during image segmentation. The aim of this study was to review the existing literature on different image segmentation methods used in medical additive manufacturing. Thirty-two publications that reported on the accuracy of bone segmentation based on computed tomography images were identified using PubMed, ScienceDirect, Scopus, and Google Scholar. The advantages and disadvantages of the different segmentation methods used in these studies were evaluated and reported accuracies were compared. The spread between the reported accuracies was large (0.04 mm - 1.9 mm). Global thresholding was the most commonly used segmentation method with accuracies under 0.6 mm. The disadvantage of this method is the extensive manual post-processing required. Advanced thresholding methods could improve the accuracy to under 0.38 mm. However, such methods are currently not included in commercial software packages. Statistical shape model methods resulted in accuracies from 0.25 mm to 1.9 mm but are only suitable for anatomical structures with moderate anatomical variations. Thresholding remains the most widely used segmentation method in medical additive manufacturing. To improve the accuracy and reduce the costs of patient-specific additive manufactured constructs, more advanced segmentation methods are required. Copyright © 2017 IPEM. Published by Elsevier Ltd. All rights reserved.

  8. An Overview on Additive Manufacturing of Polymers

    NASA Astrophysics Data System (ADS)

    Jasiuk, Iwona; Abueidda, Diab W.; Kozuch, Christopher; Pang, Siyuan; Su, Frances Y.; McKittrick, Joanna

    2018-03-01

    We present an overview on additive manufacturing (AM), also called three-dimensional printing, with a focus on polymers. First, we introduce the AM concept. Next, we outline several AM processes, including their advantages and limitations, and list common polymers that are used in commercial printers. Then, we state various AM applications and present two examples. We conclude with a global view of the AM field, its challenges, and future directions.

  9. Additive Manufacturing in Production: A Study Case Applying Technical Requirements

    NASA Astrophysics Data System (ADS)

    Ituarte, Iñigo Flores; Coatanea, Eric; Salmi, Mika; Tuomi, Jukka; Partanen, Jouni

    Additive manufacturing (AM) is expanding the manufacturing capabilities. However, quality of AM produced parts is dependent on a number of machine, geometry and process parameters. The variability of these parameters affects the manufacturing drastically and therefore standardized processes and harmonized methodologies need to be developed to characterize the technology for end use applications and enable the technology for manufacturing. This research proposes a composite methodology integrating Taguchi Design of Experiments, multi-objective optimization and statistical process control, to optimize the manufacturing process and fulfil multiple requirements imposed to an arbitrary geometry. The proposed methodology aims to characterize AM technology depending upon manufacturing process variables as well as to perform a comparative assessment of three AM technologies (Selective Laser Sintering, Laser Stereolithography and Polyjet). Results indicate that only one machine, laser-based Stereolithography, was feasible to fulfil simultaneously macro and micro level geometrical requirements but mechanical properties were not at required level. Future research will study a single AM system at the time to characterize AM machine technical capabilities and stimulate pre-normative initiatives of the technology for end use applications.

  10. Toward Efficient Thick Active PTB7 Photovoltaic Layers Using Diphenyl Ether as a Solvent Additive.

    PubMed

    Zheng, Yifan; Goh, Tenghooi; Fan, Pu; Shi, Wei; Yu, Junsheng; Taylor, André D

    2016-06-22

    The development of thick organic photovoltaics (OPV) could increase absorption in the active layer and ease manufacturing constraints in large-scale solar panel production. However, the efficiencies of most low-bandgap OPVs decrease substantially when the active layers exceed ∼100 nm in thickness (because of low crystallinity and a short exciton diffusion length). Herein, we report the use of solvent additive diphenyl ether (DPE) that facilitates the fabrication of thick (180 nm) active layers and triples the power conversion efficiency (PCE) of conventional thienothiophene-co-benzodithiophene polymer (PTB7)-based OPVs from 1.75 to 6.19%. These results demonstrate a PCE 20% higher than those of conventional (PTB7)-based OPV devices using 1,8-diiodooctane. Morphology studies reveal that DPE promotes the formation of nanofibrillar networks and ordered packing of PTB7 in the active layer that facilitate charge transport over longer distances. We further demonstrate that DPE improves the fill factor and photocurrent collection by enhancing the overall optical absorption, reducing the series resistance, and suppressing bimolecular recombination.

  11. Modeling of additive manufacturing processes for metals: Challenges and opportunities

    DOE PAGES

    Francois, Marianne M.; Sun, Amy; King, Wayne E.; ...

    2017-01-09

    Here, with the technology being developed to manufacture metallic parts using increasingly advanced additive manufacturing processes, a new era has opened up for designing novel structural materials, from designing shapes and complex geometries to controlling the microstructure (alloy composition and morphology). The material properties used within specific structural components are also designable in order to meet specific performance requirements that are not imaginable with traditional metal forming and machining (subtractive) techniques.

  12. A Novel Multiscale Design of Interfaces for Polymeric Composites and Bonded Joints using Additive Manufacturing

    DTIC Science & Technology

    2016-09-13

    AFRL-AFOSR-VA-TR-2016-0317 A Novel Multiscale Design of Interfaces for Polymeric Composites and Bonded Joints using Additive Manufacturing Pavana...Composites and Bonded Joints using Additive Manufacturing AWARD NO.: FA9550-15-1-0216 AGENCY NAME: The Air Force Office of Scientific Research (AFOSR), Ar...20 3 Additive Manufacturing for Bonded Composite Joints 21 3.1 Introduction

  13. Nucleation and growth of chimney pores during electron-beam additive manufacturing

    DOE PAGES

    Cordero, Zachary C.; Dinwiddie, Ralph B.; Immel, David; ...

    2016-12-05

    The nucleation and growth of chimney pores during powder-bed, electron-beam additive manufacturing is investigated using in-situ infrared thermography as well as microcomputed tomography of as-printed parts. The pores are found to nucleate at dimples on the part s surface, clearly demonstrating how process parameters can affect surface roughness, which can in turn affect the internal defect structure in an additive manufactured part. Based on the results of this study, several strategies for suppressing the formation of chimney pores are discussed.

  14. 3D-additive manufactured optical mount

    NASA Astrophysics Data System (ADS)

    Mammini, Paul V.; Ciscel, David; Wooten, John

    2015-09-01

    The Area Defense Anti-Munitions (ADAM) is a low cost and effective high power laser weapon system. It's designed to address and negate important threats such as short-range rockets, UAVs, and small boats. Many critical optical components operate in the system. The optics and mounts must accommodate thermal and mechanical stresses, plus maintain an exceptional wave front during operation. Lockheed Martin Space Systems Company (LMSSC) developed, designed, and currently operates ADAM. This paper covers the design and development of a key monolithic, flexured, titanium mirror mount that was manufactured by CalRAM using additive processes.

  15. Research on width control of Metal Fused-coating Additive Manufacturing based on active control

    NASA Astrophysics Data System (ADS)

    Ren, Chuan qi; Wei, Zheng ying; Wang, Xin; Du, Jun; Zhang, Shan; Zhang, Zhitong; Bai, Hao

    2017-12-01

    Given the stability of the shape of the forming layer is one of the key problems that affect the final quality of the sample morphology, taking a study on the forming process and the control method of morphology make a significant difference to metal fused-coating additive manufacturing (MFCAM) in achieving the efficient and stable forming. To improve the quality and precision of the samples of single-layer single pass, a control method of morphology based on active control was established by this paper. The real-time acquisition of image was realized by CCD and the characteristics of morphology of the forming process were simultaneously extracted. Making analysis of the characteristics of the width during the process, the relationship between the relative difference of different frames and moving speed was given. A large number of experiments are used to verify the response speed and accuracy of the system. The results show that the active system can improve the morphology of the sample and the smoothness of the width of the single channel, and increase the uniformity of width by 55.16%.

  16. Applying Additive Manufacturing to a New Liquid Oxygen Turbopump Design

    NASA Technical Reports Server (NTRS)

    O'Neal, Derek

    2016-01-01

    A liquid oxygen turbopump has been designed at Marshall Space Flight Center as part of the in-house, Advanced Manufacturing Demonstrator Engine (AMDE) project. Additive manufacturing, specifically direct metal laser sintering (DMLS) of Inconel 718, is used for 77% of the parts by mass. These parts include the impeller, turbine components, and housings. The near-net shape DMLS parts have been delivered and final machining is underway. Fabrication of the traditionally manufactured hardware is also proceeding. Testing in liquid oxygen is planned for Q2 of FY2017. This topic explores the design of the turbopump along with fabrication and material testing of the DMLS hardware.

  17. Targeted Structural Optimization with Additive Manufacturing of Metals

    NASA Technical Reports Server (NTRS)

    Burt, Adam; Hull, Patrick

    2015-01-01

    The recent advances in additive manufacturing (AM) of metals have now improved the state-of-the-art such that traditionally non-producible parts can be readily produced in a cost-effective way. Because of these advances in manufacturing technology, structural optimization techniques are well positioned to supplement and advance this new technology. The goal of this project is to develop a structural design, analysis, and optimization framework combined with AM to significantly light-weight the interior of metallic structures while maintaining the selected structural properties of the original solid. This is a new state-of-the-art capability to significantly reduce mass, while maintaining the structural integrity of the original design, something that can only be done with AM. In addition, this framework will couple the design, analysis, and fabrication process, meaning that what has been designed directly represents the produced part, thus closing the loop on the design cycle and removing human iteration between design and fabrication. This fundamental concept has applications from light-weighting launch vehicle components to in situ resource fabrication.

  18. An Additive Manufacturing Test Artifact

    PubMed Central

    Moylan, Shawn; Slotwinski, John; Cooke, April; Jurrens, Kevin; Donmez, M Alkan

    2014-01-01

    A test artifact, intended for standardization, is proposed for the purpose of evaluating the performance of additive manufacturing (AM) systems. A thorough analysis of previously proposed AM test artifacts as well as experience with machining test artifacts have inspired the design of the proposed test artifact. This new artifact is designed to provide a characterization of the capabilities and limitations of an AM system, as well as to allow system improvement by linking specific errors measured in the test artifact to specific sources in the AM system. The proposed test artifact has been built in multiple materials using multiple AM technologies. The results of several of the builds are discussed, demonstrating how the measurement results can be used to characterize and improve a specific AM system. PMID:26601039

  19. Additive Manufacturing and Casting Technology Comparison: Mechanical Properties, Productivity and Cost Benchmark

    NASA Astrophysics Data System (ADS)

    Vevers, A.; Kromanis, A.; Gerins, E.; Ozolins, J.

    2018-04-01

    The casting technology is one of the oldest production technologies in the world but in the recent years metal additive manufacturing also known as metal 3D printing has been evolving with huge steps. Both technologies have capabilities to produce parts with internal holes and at first glance surface roughness is similar for both technologies, which means that for precise dimensions parts have to be machined in places where precise fit is necessary. Benchmark tests have been made to find out if parts which are produced with metal additive manufacturing can be used to replace parts which are produced with casting technology. Most of the comparative tests have been made with GJS-400-15 grade which is one of the most popular cast iron grades. To compare mechanical properties samples have been produced using additive manufacturing and tested for tensile strength, hardness, surface roughness and microstructure and then the results have been compared with the samples produced with casting technology. In addition, both technologies have been compared in terms of the production time and production costs to see if additive manufacturing is competitive with the casting technology. The original paper has been written in the Latvian language as part of the Master Thesis within the framework of the production technology study programme at Riga Technical University.

  20. Additive Manufactured Superconducting Cavities

    NASA Astrophysics Data System (ADS)

    Holland, Eric; Rosen, Yaniv; Woolleet, Nathan; Materise, Nicholas; Voisin, Thomas; Wang, Morris; Mireles, Jorge; Carosi, Gianpaolo; Dubois, Jonathan

    Superconducting radio frequency cavities provide an ultra-low dissipative environment, which has enabled fundamental investigations in quantum mechanics, materials properties, and the search for new particles in and beyond the standard model. However, resonator designs are constrained by limitations in conventional machining techniques. For example, current through a seam is a limiting factor in performance for many waveguide cavities. Development of highly reproducible methods for metallic parts through additive manufacturing, referred to colloquially as 3D printing\\x9D, opens the possibility for novel cavity designs which cannot be implemented through conventional methods. We present preliminary investigations of superconducting cavities made through a selective laser melting process, which compacts a granular powder via a high-power laser according to a digitally defined geometry. Initial work suggests that assuming a loss model and numerically optimizing a geometry to minimize dissipation results in modest improvements in device performance. Furthermore, a subset of titanium alloys, particularly, a titanium, aluminum, vanadium alloy (Ti - 6Al - 4V) exhibits properties indicative of a high kinetic inductance material. This work is supported by LDRD 16-SI-004.

  1. Environmental Cracking and Irradiation Resistant Stainless Steels by Additive Manufacturing

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rebak, Raul B.; Lou, Xiaoyuan

    Metal additive manufacturing (AM), or metal 3D printing is an emergent advanced manufacturing method that can create near net shape geometries directly from computer models. This technology can provide the capability to rapidly fabricate complex parts that may be required to enhance the integrity of reactor internals components. Such opportunities may be observed during a plant refueling outage and AM parts can be rapidly custom designed, manufactured and deployed within the outage interval. Additive manufacturing of stainless steel (SS) components can add business benefits on fast delivery on repair hardware, installation tooling, new design prototypes tests, etc. For the nuclearmore » industry, the supply chain is always an issue for reactor service. AM can provide through-life supply chain (40-60 years) for high-value low-volume components. In the meantime, the capability of generating complex geometries and functional gradient materials will improve the performance, reduce the overall component cost, plant asset management cost and increase the plant reliability by the improvement in materials performance in nuclear environments. While extensive work has been conducted regarding additively manufacturing of austenitic SS parts, most efforts focused only on basic attributes such as porosity, residual stress, basic tensile properties, along with components yield and process monitoring. Little work has been done to define and evaluate the material requirements for nuclear applications. Technical gaps exist, which limit this technology adoption in the nuclear industry, which includes high manufacturing cost, unknown risks, limited nuclear related data, lack of specification and qualification methods, and no prior business experience. The main objective of this program was to generate research data to address all these technical gaps and establish a commercial practice to use AM technology in the nuclear power industry. The detailed objectives are listed as follows

  2. Electron beam additive manufacturing with wire - Analysis of the process

    NASA Astrophysics Data System (ADS)

    Weglowski, Marek St.; Błacha, Sylwester; Pilarczyk, Jan; Dutkiewicz, Jan; Rogal, Łukasz

    2018-05-01

    The electron beam additive manufacturing process with wire is a part of global trend to find fast and efficient methods for producing complex shapes elements from costly metal alloys such as stainless steels, nickel alloys, titanium alloys etc. whose production by other conventional technologies is unprofitable or technically impossible. Demand for additive manufacturing is linked to the development of new technologies in the automotive, aerospace and machinery industries. The aim of the presented work was to carried out research on electron beam additive manufacturing with a wire as a deposited (filler) material. The scope of the work was to investigate the influence of selected technological parameters such as: wire feed rate, beam current, travelling speed, acceleration voltage on stability of the deposition process and geometric dimensions of the padding welds. The research revealed that, at low beam currents, the deposition process is unstable. The padding weld reinforcement is non-uniform. Irregularity of the width, height and straightness of the padding welds can be observed. At too high acceleration voltage and beam current, burn-through of plate and excess penetration weld can be revealed. The achieved results and gained knowledge allowed to produce, based on EBAM with wire process, whole structure from stainless steel.

  3. Characterization of an Additive Manufactured TiAl Alloy-Steel Joint Produced by Electron Beam Welding.

    PubMed

    Basile, Gloria; Baudana, Giorgio; Marchese, Giulio; Lorusso, Massimo; Lombardi, Mariangela; Ugues, Daniele; Fino, Paolo; Biamino, Sara

    2018-01-17

    In this work, the characterization of the assembly of a steel shaft into a γ-TiAl part for turbocharger application, obtained using Electron Beam Welding (EBW) technology with a Ni-based filler, was carried out. The Ti-48Al-2Nb-0.7Cr-0.3Si (at %) alloy part was produced by Electron Beam Melting (EBM). This additive manufacturing technology allows the production of a lightweight part with complex shapes. The replacement of Nickel-based superalloys with TiAl alloys in turbocharger automotive applications will lead to an improvement of the engine performance and a substantial reduction in fuel consumption and emission. The welding process allows a promising joint to be obtained, not affecting the TiAl microstructure. Nevertheless, it causes the formation of diffusive layers between the Ni-based filler and both steel and TiAl, with the latter side being characterized by a very complex microstructure, which was fully characterized in this paper by means of Scanning Electron Microscopy, Energy Dispersive X-ray Spectroscopy, and nanoindentation. The diffusive interface has a thickness of about 6 µm, and it is composed of several layers. Specifically, from the TiAl alloy side, we find a layer of Ti₃Al followed by Al₃NiTi₂ and AlNi₂Ti. Subsequently Ni becomes more predominant, with a first layer characterized by abundant carbide/boride precipitation, and a second layer characterized by Si-enrichment. Then, the chemical composition of the Ni-based filler is gradually reached.

  4. Paradigm Shift Additive Manufacturing and the New Way of War

    DTIC Science & Technology

    2016-12-01

    keep costs low: Simple parts are easier to make. Once a product design has been selected and tooling has been obtained, a change in design becomes...adversary’s OODA loop through rapid design and manufacturing . We need to do this; enable this capabil- ity now before our adversaries do, as they might not...35 Defense AT&L: November-December 2016 Paradigm Shift Additive Manufacturing and the New Way of War Brett P. Conner Conner is an associate

  5. Applying Additive Manufacturing to a New Liquid Oxygen Turbopump Design

    NASA Technical Reports Server (NTRS)

    O’Neal, T. Derek

    2016-01-01

    A liquid oxygen turbopump has been designed at Marshall Space Flight Center as part of the in-house, Advanced Manufacturing Demonstrator Engine (AMDE) project. Additive manufacturing, specifically direct metal laser sintering (DMLS) of Inconel 718, is used for 77% of the parts by mass. These parts include the impeller, turbine components, and housings. This paper discusses the impacts of the DMLS fabrication technique on the design of the turbopump and lessons learned during DMLS hardware fabrication and material testing.

  6. Application of Additively Manufactured Components in Rocket Engine Turbopumps

    NASA Technical Reports Server (NTRS)

    Calvert, Marty, Jr.; Hanks, Andrew; Schmauch, Preston; Delessio, Steve

    2015-01-01

    The use of additive manufacturing technology has the potential to revolutionize the development of turbopump components in liquid rocket engines. When designing turbomachinery with the additive process there are several benefits and risks that are leveraged relative to a traditional development cycle. This topic explores the details and development of a 90,000 RPM Liquid Hydrogen Turbopump from which 90% of the parts were derived from the additive process. This turbopump was designed, developed and will be tested later this year at Marshall Space Flight Center.

  7. Effects of Defects in Laser Additive Manufactured Ti-6Al-4V on Fatigue Properties

    NASA Astrophysics Data System (ADS)

    Wycisk, Eric; Solbach, Andreas; Siddique, Shafaqat; Herzog, Dirk; Walther, Frank; Emmelmann, Claus

    Laser Additive Manufacturing (LAM) enables economical production of complex lightweight structures as well as patient individual implants. Due to these possibilities the additive manufacturing technology gains increasing importance in the aircraft and the medical industry. Yet these industries obtain high quality standards and demand predictability of material properties for static and dynamic load cases. However, especially fatigue and crack propagation properties are not sufficiently determined. Therefore this paper presents an analysis and simulation of crack propagation behavior considering Laser Additive Manufacturing specific defects, such as porosity and surface roughness. For the mechanical characterization of laser additive manufactured titanium alloy Ti-6Al-4V, crack propagation rates are experimentally determined and used for an analytical modeling and simulation of fatigue. Using experimental results from HCF tests and simulated data, the fatigue and crack resistance performance is analyzed considering material specific defects and surface roughness. The accumulated results enable the reliable prediction of the defects influence on fatigue life of laser additive manufactured titanium components.

  8. Tribology of Polymer Matrix Composites (PMCs) Fabricated by Additive Manufacturing (AM)

    NASA Technical Reports Server (NTRS)

    Gupta, S.; Dunnigan, R.; Salem, A.; Kuentz, L.; Halbig, M. C.; Singh, M.

    2016-01-01

    The integral process of depositing thin layers of material, one after another, until the designed component is created is collectively referred to as Additive Manufacturing (AM). Fused deposition process (FDP) is a type of AM where feedstock is extruded into filaments which then are deposited by 3D printing, and the solidification occurs during cooling of the melt. Currently, complex structures are being fabricated by commercial and open source desktop 3D printers. Recently, metal powder containing composite filaments based on polylactic acid (PLA) and acrylonitrile butadiene styrene (ABS) have emerged, which could be utilized for multifunctional applications. For further deployment in the field, especially for aerospace and ground-based applications, it is critical to understand the tribological behavior of 3D printed materials. In this presentation, we will report the tribological behavior of different polymer matrix composites fabricated by fused deposition process. These results will be compared with the base polymer systems. During this study, the tribological behavior of all the samples will be evaluated with tab-on-disc method and compared for different metallic powder reinforcements.

  9. Defense Additive Manufacturing: DOD Needs to Systematically Track Department-wide 3D Printing Efforts

    DTIC Science & Technology

    2015-10-01

    Clip Additively Manufactured • The Navy installed a 3D printer aboard the USS Essex to demonstrate the ability to additively develop and produce...desired result and vision to have the capability on the fleet. These officials stated that the Navy plans to install 3D printers on two additional...DEFENSE ADDITIVE MANUFACTURING DOD Needs to Systematically Track Department-wide 3D Printing Efforts Report to

  10. Environmental and Economic Implications of Distributed Additive Manufacturing: The Case of Injection Mold Tooling: Environmental Implications of Additive Manufacturing

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Huang, Runze; Riddle, Matthew E.; Graziano, Diane

    Additive manufacturing (AM) holds great potentials in enabling superior engineering functionality, streamlining supply chains, and reducing life cycle impacts compared to conventional manufacturing (CM). This study estimates the net changes in supply-chain lead time, life cycle primary energy consumption, greenhouse gas (GHG) emissions, and life cycle costs (LCC) associated with AM technologies for the case of injection molding, to shed light on the environmental and economic advantages of a shift from international or onshore CM to AM in the United States. A systems modeling framework is developed, with integrations of lead-time analysis, life cycle inventory analysis, LCC model, and scenariosmore » considering design differences, supply-chain options, productions, maintenance, and AM technological developments. AM yields a reduction potential of 3% to 5% primary energy, 4% to 7% GHG emissions, 12% to 60% lead time, and 15% to 35% cost over 1 million cycles of the injection molding production depending on the AM technology advancement in future. The economic advantages indicate the significant role of AM technology in raising global manufacturing competitiveness of local producers, while the relatively small environmental benefits highlight the necessity of considering trade-offs and balance techniques between environmental and economic performances when AM is adopted in the tooling industry. The results also help pinpoint the technological innovations in AM that could lead to broader benefits in future.« less

  11. Environmental and Economic Implications of Distributed Additive Manufacturing: The Case of Injection Mold Tooling: Environmental Implications of Additive Manufacturing

    DOE PAGES

    Huang, Runze; Riddle, Matthew E.; Graziano, Diane; ...

    2017-08-26

    Additive manufacturing (AM) holds great potentials in enabling superior engineering functionality, streamlining supply chains, and reducing life cycle impacts compared to conventional manufacturing (CM). This study estimates the net changes in supply-chain lead time, life cycle primary energy consumption, greenhouse gas (GHG) emissions, and life cycle costs (LCC) associated with AM technologies for the case of injection molding, to shed light on the environmental and economic advantages of a shift from international or onshore CM to AM in the United States. A systems modeling framework is developed, with integrations of lead-time analysis, life cycle inventory analysis, LCC model, and scenariosmore » considering design differences, supply-chain options, productions, maintenance, and AM technological developments. AM yields a reduction potential of 3% to 5% primary energy, 4% to 7% GHG emissions, 12% to 60% lead time, and 15% to 35% cost over 1 million cycles of the injection molding production depending on the AM technology advancement in future. The economic advantages indicate the significant role of AM technology in raising global manufacturing competitiveness of local producers, while the relatively small environmental benefits highlight the necessity of considering trade-offs and balance techniques between environmental and economic performances when AM is adopted in the tooling industry. The results also help pinpoint the technological innovations in AM that could lead to broader benefits in future.« less

  12. Autonomously Self-Adhesive Hydrogels as Building Blocks for Additive Manufacturing.

    PubMed

    Deng, Xudong; Attalla, Rana; Sadowski, Lukas P; Chen, Mengsu; Majcher, Michael J; Urosev, Ivan; Yin, Da-Chuan; Selvaganapathy, P Ravi; Filipe, Carlos D M; Hoare, Todd

    2018-01-08

    We report a simple method of preparing autonomous and rapid self-adhesive hydrogels and their use as building blocks for additive manufacturing of functional tissue scaffolds. Dynamic cross-linking between 2-aminophenylboronic acid-functionalized hyaluronic acid and poly(vinyl alcohol) yields hydrogels that recover their mechanical integrity within 1 min after cutting or shear under both neutral and acidic pH conditions. Incorporation of this hydrogel in an interpenetrating calcium-alginate network results in an interfacially stiffer but still rapidly self-adhesive hydrogel that can be assembled into hollow perfusion channels by simple contact additive manufacturing within minutes. Such channels withstand fluid perfusion while retaining their dimensions and support endothelial cell growth and proliferation, providing a simple and modular route to produce customized cell scaffolds.

  13. A Fully Nonmetallic Gas Turbine Engine Enabled by Additive Manufacturing, Part II: Additive Manufacturing and Characterization of Polymer Composites

    NASA Technical Reports Server (NTRS)

    Chuang, Kathy C.; Grady, Joseph E.; Arnold, Steven M.; Draper, Robert D.; Shin, Eugene; Patterson, Clark; Santelle, Tom; Lao, Chao; Rhein, Morgan; Mehl, Jeremy

    2015-01-01

    This publication is the second part of the three part report of the project entitled "A Fully Nonmetallic Gas Turbine Engine Enabled by Additive Manufacturing" funded by NASA Aeronautics Research Institute (NARI). The objective of this project was to conduct additive manufacturing to produce aircraft engine components by Fused Deposition Modeling (FDM), using commercially available polyetherimides-Ultem 9085 and experimental Ultem 1000 mixed with 10% chopped carbon fiber. A property comparison between FDM-printed and injection molded coupons for Ultem 9085, Ultem 1000 resin and the fiber-filled composite Ultem 1000 was carried out. Furthermore, an acoustic liner was printed from Ultem 9085 simulating conventional honeycomb structured liners and tested in a wind tunnel. Composite compressor inlet guide vanes were also printed using fiber-filled Ultem 1000 filaments and tested in a cascade rig. The fiber-filled Ultem 1000 filaments and composite vanes were characterized by scanning electron microscope (SEM) and acid digestion to determine the porosity of FDM-printed articles which ranged from 25 to 31%. Coupons of Ultem 9085, experimental Ultem 1000 composites and XH6050 resin were tested at room temperature and 400F to evaluate their corresponding mechanical properties. A preliminary modeling was also initiated to predict the mechanical properties of FDM-printed Ultem 9085 coupons in relation to varied raster angles and void contents, using the GRC-developed MAC/GMC program.

  14. Additive Manufacturing of Parts and Tooling in Robotic Systems

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Love, Lonnie J.; Hassen, Ahmed A.; Chesser, Phillip C.

    ORNL worked with Transcend Robotics, LLC to explore additive manufacturing of the two-piece compression body for their ARTI mobile robot platform. Extrusion compression molding was identified as an effective means of manufacturing these parts. ORNL consulted on modifications to the housing design to accommodate the selected manufacturing process. Parts were printed using ORNL's FDM machines for testing and evaluation of the design as a precursor to molding the parts. The assembly and evaluation of the parts proved favorable and minor design changes to improve assembly and performance were identified.The goal is to develop a light weight and rugged two-part roboticmore » enclosure for an unmanned ground vehicle UGV) that will be used in search and rescue applications. The FDM parts fabricated by ORNL allowed Transcend Robotics to assemble a prototype robot and verify that the new parts will meet the performance requirements. ORNL fabricated enclosure parts out of ABS and Nylon 12 materials such that the design could be tested prior to fabricating tooling for compression molding of Nylon 6 with carbon fiber fill. The robot was performance tested and compared with the previous manufacturing techniques and found to have superior performance.« less

  15. Additive Manufacturing of Molds for Fabrication of Insulated Concrete Block

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Love, Lonnie J.; Lloyd, Peter D.

    ORNL worked with concrete block manufacturer, NRG Insulated Block, to demonstrate additive manufacturing of a multi-component block mold for its line of insulated blocks. Solid models of the mold parts were constructed from existing two-dimensional drawings and the parts were fabricated on a Stratasys Fortus 900 using ULTEM 9085. Block mold parts were delivered to NRG and installed on one of their fabrication lines. While form and fit were acceptable, the molds failed to function during NRG’s testing.

  16. Process development for green part printing using binder jetting additive manufacturing

    NASA Astrophysics Data System (ADS)

    Miyanaji, Hadi; Orth, Morgan; Akbar, Junaid Muhammad; Yang, Li

    2018-05-01

    Originally developed decades ago, the binder jetting additive manufacturing (BJ-AM) process possesses various advantages compared to other additive manufacturing (AM) technologies such as broad material compatibility and technological expandability. However, the adoption of BJ-AM has been limited by the lack of knowledge with the fundamental understanding of the process principles and characteristics, as well as the relatively few systematic design guideline that are available. In this work, the process design considerations for BJ-AM in green part fabrication were discussed in detail in order to provide a comprehensive perspective of the design for additive manufacturing for the process. Various process factors, including binder saturation, in-process drying, powder spreading, powder feedstock characteristics, binder characteristics and post-process curing, could significantly affect the printing quality of the green parts such as geometrical accuracy and part integrity. For powder feedstock with low flowability, even though process parameters could be optimized to partially offset the printing feasibility issue, the qualities of the green parts will be intrinsically limited due to the existence of large internal voids that are inaccessible to the binder. In addition, during the process development, the balanced combination between the saturation level and in-process drying is of critical importance in the quality control of the green parts.

  17. Additive Manufacturing: Building the Pathway Towards Process and Material Qualification”

    DOE PAGES

    Carpenter, John S.; Beese, Allison M.; Bourell, David L.; ...

    2016-06-14

    The potential benefits of metal additive manufacturing, as compared with more traditional, subtractive-only approaches, has created excitement within design circles seeking to take advantage of the ability to build and repair complex shapes, to integrate or consolidate multiple parts and minimize joining concerns, and to locally tailor material properties to increase functionality. Tempering the excitement of designers, however, has been concerns with the material deposited by the process. It is not enough for a part to ‘look’ right from a geometric perspective. Rather, the metallurgical aspects associated with the material being deposited must ‘look’ and ‘behave’ correctly along with themore » aforementioned geometric accuracy. Finally, without elucidation of the connections between processing, microstructure, properties, and performance from a materials science perspective, metal additive manufacturing will not realize its potential to change the manufacturing world for property and performance-critical engineering applications.« less

  18. Evaluation of Additively Manufactured Metals for Use in Oxygen Systems Project

    NASA Technical Reports Server (NTRS)

    Tylka, Jonathan; Cooper, Ken; Peralta, Stephen; Wilcutt, Terrence; Hughitt, Brian; Generazio, Edward

    2016-01-01

    Space Launch System, Commercial Resupply, and Commercial Crew programs have published intent to use additively manufactured (AM) components in propulsion systems and are likely to include various life support systems in the future. Parts produced by these types of additive manufacturing techniques have not been fully evaluated for use in oxygen systems and the inherent risks have not been fully identified. Some areas of primary concern in the SLS process with respect to oxygen compatibility may be the porosity of the printed parts, fundamental differences in microstructure of an AM part as compared to traditional materials, or increased risk of shed metal particulate into an oxygen system. If an ignition were to occur the printed material could be more flammable than components manufactured from a traditional billet of raw material and/or present a significant hazards if not identified and rigorously studied in advance of implementation into an oxygen system.

  19. Metal Big Area Additive Manufacturing: Process Modeling and Validation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Simunovic, Srdjan; Nycz, Andrzej; Noakes, Mark W

    Metal Big Area Additive Manufacturing (mBAAM) is a new additive manufacturing (AM) technology for printing large-scale 3D objects. mBAAM is based on the gas metal arc welding process and uses a continuous feed of welding wire to manufacture an object. An electric arc forms between the wire and the substrate, which melts the wire and deposits a bead of molten metal along the predetermined path. In general, the welding process parameters and local conditions determine the shape of the deposited bead. The sequence of the bead deposition and the corresponding thermal history of the manufactured object determine the long rangemore » effects, such as thermal-induced distortions and residual stresses. Therefore, the resulting performance or final properties of the manufactured object are dependent on its geometry and the deposition path, in addition to depending on the basic welding process parameters. Physical testing is critical for gaining the necessary knowledge for quality prints, but traversing the process parameter space in order to develop an optimized build strategy for each new design is impractical by pure experimental means. Computational modeling and optimization may accelerate development of a build process strategy and saves time and resources. Because computational modeling provides these opportunities, we have developed a physics-based Finite Element Method (FEM) simulation framework and numerical models to support the mBAAM process s development and design. In this paper, we performed a sequentially coupled heat transfer and stress analysis for predicting the final deformation of a small rectangular structure printed using the mild steel welding wire. Using the new simulation technologies, material was progressively added into the FEM simulation as the arc weld traversed the build path. In the sequentially coupled heat transfer and stress analysis, the heat transfer was performed to calculate the temperature evolution, which was used in a stress

  20. Rapid prototyping of multi-scale biomedical microdevices by combining additive manufacturing technologies.

    PubMed

    Hengsbach, Stefan; Lantada, Andrés Díaz

    2014-08-01

    The possibility of designing and manufacturing biomedical microdevices with multiple length-scale geometries can help to promote special interactions both with their environment and with surrounding biological systems. These interactions aim to enhance biocompatibility and overall performance by using biomimetic approaches. In this paper, we present a design and manufacturing procedure for obtaining multi-scale biomedical microsystems based on the combination of two additive manufacturing processes: a conventional laser writer to manufacture the overall device structure, and a direct-laser writer based on two-photon polymerization to yield finer details. The process excels for its versatility, accuracy and manufacturing speed and allows for the manufacture of microsystems and implants with overall sizes up to several millimeters and with details down to sub-micrometric structures. As an application example we have focused on manufacturing a biomedical microsystem to analyze the impact of microtextured surfaces on cell motility. This process yielded a relevant increase in precision and manufacturing speed when compared with more conventional rapid prototyping procedures.

  1. Social aspects in additive manufacturing of pharmaceutical products.

    PubMed

    Lind, Johanna; Kälvemark Sporrong, Sofia; Kaae, Susanne; Rantanen, Jukka; Genina, Natalja

    2017-08-01

    Additive manufacturing (AM) techniques, such as drug printing, represent a new engineering approach that can implement the concept of personalized medicine via on-demand manufacturing of dosage forms with individually adjusted doses. Implementation of AM principles, such as pharmacoprinting, will challenge the entire drug distribution chain and affect the society at different levels. Areas covered: This work summarizes the concept of personalized medicine and gives an overview of possibilities for monitoring patients' health. The most recent activities in the field of printing technologies for fabrication of dosage forms and 'polypills' with flexible doses and tailored release profiles are reviewed. Different scenarios for the drug distribution chain with the required adjustments in drug logistics, quality systems and environmental safety are discussed, as well as whether AM will be used for production of on-demand medicine. The impact of such changes in the distribution chain on regulation, healthcare professionals and patients are highlighted. Expert opinion: Drug manufacturing by traditional methods is well-established, but it lacks the possibility for on-demand personalized drug production. With the recent approval of the first printed medicine, society should be prepared for the changes that will follow the introduction of printed pharmaceuticals.

  2. A Fully Non-Metallic Gas Turbine Engine Enabled by Additive Manufacturing

    NASA Technical Reports Server (NTRS)

    Grady, Joseph E.

    2015-01-01

    The Non-Metallic Gas Turbine Engine project, funded by NASA Aeronautics Research Institute, represents the first comprehensive evaluation of emerging materials and manufacturing technologies that will enable fully nonmetallic gas turbine engines. This will be achieved by assessing the feasibility of using additive manufacturing technologies to fabricate polymer matrix composite and ceramic matrix composite turbine engine components. The benefits include: 50 weight reduction compared to metallic parts, reduced manufacturing costs, reduced part count and rapid design iterations. Two high payoff metallic components have been identified for replacement with PMCs and will be fabricated using fused deposition modeling (FDM) with high temperature polymer filaments. The CMC effort uses a binder jet process to fabricate silicon carbide test coupons and demonstration articles. Microstructural analysis and mechanical testing will be conducted on the PMC and CMC materials. System studies will assess the benefits of fully nonmetallic gas turbine engine in terms of fuel burn, emissions, reduction of part count, and cost. The research project includes a multidisciplinary, multiorganization NASA - industry team that includes experts in ceramic materials and CMCs, polymers and PMCs, structural engineering, additive manufacturing, engine design and analysis, and system analysis.

  3. The Development of High Temperature Thermoplastic Composite Materials for Additive Manufactured Autoclave Tooling

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kunc, Vlastimil; Duty, Chad E.; Lindahl, John M.

    2017-08-01

    In this work, ORNL and Techmer investigated and screened different high temperature thermoplastic reinforced materials to fabricate composite molds for autoclave processes using Additive Manufacturing (AM) techniques. This project directly led to the development and commercial release of two printable, high temperature composite materials available through Techmer PM. These new materials are targeted for high temperature tooling made via large scale additive manufacturing.

  4. A Fully Nonmetallic Gas Turbine Engine Enabled by Additive Manufacturing of Ceramic Composites. Part III; Additive Manufacturing and Characterization of Ceramic Composites

    NASA Technical Reports Server (NTRS)

    Halbig, Michael C.; Grady, Joseph E.; Singh, Mrityunjay; Ramsey, Jack; Patterson, Clark; Santelle, Tom

    2015-01-01

    This publication is the third part of a three part report of the project entitled "A Fully Nonmetallic Gas Turbine Engine Enabled by Additive Manufacturing" funded by NASA Aeronautics Research Institute (NARI). The objective of this project was to conduct additive manufacturing to produce ceramic matrix composite materials and aircraft engine components by the binder jet process. Different SiC powders with median sizes ranging from 9.3 to 53.0 microns were investigated solely and in powder blends in order to maximize powder packing. Various infiltration approaches were investigated to include polycarbosilane (SMP-10), phenolic, and liquid silicon. Single infiltrations of SMP-10 and phenolic only slightly filled in the interior. When the SMP-10 was loaded with sub-micron sized SiC powders, the infiltrant gave a much better result of filling in the interior. Silicon carbide fibers were added to the powder bed to make ceramic matrix composite materials. Microscopy showed that the fibers were well distributed with no preferred orientation on the horizontal plane and fibers in the vertical plane were at angles as much as 45deg. Secondary infiltration steps were necessary to further densify the material. Two to three extra infiltration steps of SMP-10 increased the density by 0.20 to 0.55 g/cc. However, the highest densities achieved were 2.10 to 2.15 g/cc. Mechanical tests consisting of 4 point bend tests were conducted. Samples from the two CMC panels had higher strengths and strains to failure than the samples from the two nonfiber reinforced panels. The highest strengths were from Set N with 65 vol% fiber loading which had an average strength of 66 MPa. Analysis of the fracture surfaces did not reveal pullout of the reinforcing fibers. Blunt fiber failure suggested that there was not composite behavior. The binder jet additive manufacturing method was used to also demonstrate the fabrication of turbine engine vane components of two different designs and sizes. The

  5. Enhanced additive manufacturing with a reciprocating platen

    DOEpatents

    Lind, Randall F.; Blue, Craig A.; Love, Lonnie J.; Post, Brian K.; Lloyd, Peter D.

    2018-02-06

    An additive manufacturing extrusion head that includes a heated nozzle for accepting a feedstock and extruding the feedstock onto a substrate at a deposition plane, the nozzle having a longitudinal extrusion axis. A reciprocating platen surrounds the nozzle, the platen operable to reciprocate along the extrusion axis at or above the deposition plane as the nozzle extrudes feedstock onto the substrate; and wherein the platen flattens the extruded feedstock such that it does not protrude above the deposition plane as the extrusion head traverses over the substrate.

  6. Mechanical Properties of Austenitic Stainless Steel Made by Additive Manufacturing.

    PubMed

    Luecke, William E; Slotwinski, John A

    2014-01-01

    Using uniaxial tensile and hardness testing, we evaluated the variability and anisotropy of the mechanical properties of an austenitic stainless steel, UNS S17400, manufactured by an additive process, selective laser melting. Like wrought materials, the mechanical properties depend on the orientation introduced by the processing. The recommended stress-relief heat treatment increases the tensile strength, reduces the yield strength, and decreases the extent of the discontinuous yielding. The mechanical properties, assessed by hardness, are very uniform across the build plate, but the stress-relief heat treatment introduced a small non-uniformity that had no correlation to position on the build plate. Analysis of the mechanical property behavior resulted in four conclusions. (1) The within-build and build-to-build tensile properties of the UNS S17400 stainless steel are less repeatable than mature engineering structural alloys, but similar to other structural alloys made by additive manufacturing. (2) The anisotropy of the mechanical properties of the UNS S17400 material of this study is larger than that of mature structural alloys, but is similar to other structural alloys made by additive manufacturing. (3) The tensile mechanical properties of the UNS S17400 material fabricated by selective laser melting are very different from those of wrought, heat-treated 17-4PH stainless steel. (4) The large discontinuous yielding strain in all tests resulted from the formation and propagation of Lüders bands.

  7. NASA's Additive Manufacturing Development Materials Science to Technology Infusion - Connecting the Digital Dots

    NASA Technical Reports Server (NTRS)

    Vickers, John

    2017-01-01

    At NASA, the first steps of the Journey to Mars are well underway with the development of NASA's next generation launch system and investments in research and technologies that should increase the affordability, capability, and safety of exploration activities. Additive Manufacturing presents a disruptive opportunity for NASA to design and manufacture hardware with new materials at dramatically reduced cost and schedule. Opportunities to incorporate additive manufacturing align very well with NASA missions and with most NASA programs related to space, science, and aeronautics. The Agency also relies on many partnerships with other government agencies, industry and academia.

  8. Multilayer electronic component systems and methods of manufacture

    NASA Technical Reports Server (NTRS)

    Thompson, Dane (Inventor); Wang, Guoan (Inventor); Kingsley, Nickolas D. (Inventor); Papapolymerou, Ioannis (Inventor); Tentzeris, Emmanouil M. (Inventor); Bairavasubramanian, Ramanan (Inventor); DeJean, Gerald (Inventor); Li, RongLin (Inventor)

    2010-01-01

    Multilayer electronic component systems and methods of manufacture are provided. In this regard, an exemplary system comprises a first layer of liquid crystal polymer (LCP), first electronic components supported by the first layer, and a second layer of LCP. The first layer is attached to the second layer by thermal bonds. Additionally, at least a portion of the first electronic components are located between the first layer and the second layer.

  9. Investigation of microstructure in additive manufactured Inconel 625 by spatially resolved neutron transmission spectroscopy

    DOE PAGES

    Tremsin, Anton S.; Gao, Yan; Dial, Laura C.; ...

    2016-07-08

    Non-destructive testing techniques based on neutron imaging and diffraction can provide information on the internal structure of relatively thick metal samples (up to several cm), which are opaque to other conventional non-destructive methods. Spatially resolved neutron transmission spectroscopy is an extension of traditional neutron radiography, where multiple images are acquired simultaneously, each corresponding to a narrow range of energy. The analysis of transmission spectra enables studies of bulk microstructures at the spatial resolution comparable to the detector pixel. In this study we demonstrate the possibility of imaging (with ~100 μm resolution) distribution of some microstructure properties, such as residual strain,more » texture, voids and impurities in Inconel 625 samples manufactured with an additive manufacturing method called direct metal laser melting (DMLM). Although this imaging technique can be implemented only in a few large-scale facilities, it can be a valuable tool for optimization of additive manufacturing techniques and materials and for correlating bulk microstructure properties to manufacturing process parameters. Additionally, the experimental strain distribution can help validate finite element models which many industries use to predict the residual stress distributions in additive manufactured components.« less

  10. Investigation of microstructure in additive manufactured Inconel 625 by spatially resolved neutron transmission spectroscopy.

    PubMed

    Tremsin, Anton S; Gao, Yan; Dial, Laura C; Grazzi, Francesco; Shinohara, Takenao

    2016-01-01

    Non-destructive testing techniques based on neutron imaging and diffraction can provide information on the internal structure of relatively thick metal samples (up to several cm), which are opaque to other conventional non-destructive methods. Spatially resolved neutron transmission spectroscopy is an extension of traditional neutron radiography, where multiple images are acquired simultaneously, each corresponding to a narrow range of energy. The analysis of transmission spectra enables studies of bulk microstructures at the spatial resolution comparable to the detector pixel. In this study we demonstrate the possibility of imaging (with ~100 μm resolution) distribution of some microstructure properties, such as residual strain, texture, voids and impurities in Inconel 625 samples manufactured with an additive manufacturing method called direct metal laser melting (DMLM). Although this imaging technique can be implemented only in a few large-scale facilities, it can be a valuable tool for optimization of additive manufacturing techniques and materials and for correlating bulk microstructure properties to manufacturing process parameters. In addition, the experimental strain distribution can help validate finite element models which many industries use to predict the residual stress distributions in additive manufactured components.

  11. Investigation of microstructure in additive manufactured Inconel 625 by spatially resolved neutron transmission spectroscopy

    NASA Astrophysics Data System (ADS)

    Tremsin, Anton S.; Gao, Yan; Dial, Laura C.; Grazzi, Francesco; Shinohara, Takenao

    2016-01-01

    Non-destructive testing techniques based on neutron imaging and diffraction can provide information on the internal structure of relatively thick metal samples (up to several cm), which are opaque to other conventional non-destructive methods. Spatially resolved neutron transmission spectroscopy is an extension of traditional neutron radiography, where multiple images are acquired simultaneously, each corresponding to a narrow range of energy. The analysis of transmission spectra enables studies of bulk microstructures at the spatial resolution comparable to the detector pixel. In this study we demonstrate the possibility of imaging (with 100 μm resolution) distribution of some microstructure properties, such as residual strain, texture, voids and impurities in Inconel 625 samples manufactured with an additive manufacturing method called direct metal laser melting (DMLM). Although this imaging technique can be implemented only in a few large-scale facilities, it can be a valuable tool for optimization of additive manufacturing techniques and materials and for correlating bulk microstructure properties to manufacturing process parameters. In addition, the experimental strain distribution can help validate finite element models which many industries use to predict the residual stress distributions in additive manufactured components.

  12. Investigation of microstructure in additive manufactured Inconel 625 by spatially resolved neutron transmission spectroscopy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tremsin, Anton S.; Gao, Yan; Dial, Laura C.

    Non-destructive testing techniques based on neutron imaging and diffraction can provide information on the internal structure of relatively thick metal samples (up to several cm), which are opaque to other conventional non-destructive methods. Spatially resolved neutron transmission spectroscopy is an extension of traditional neutron radiography, where multiple images are acquired simultaneously, each corresponding to a narrow range of energy. The analysis of transmission spectra enables studies of bulk microstructures at the spatial resolution comparable to the detector pixel. In this study we demonstrate the possibility of imaging (with ~100 μm resolution) distribution of some microstructure properties, such as residual strain,more » texture, voids and impurities in Inconel 625 samples manufactured with an additive manufacturing method called direct metal laser melting (DMLM). Although this imaging technique can be implemented only in a few large-scale facilities, it can be a valuable tool for optimization of additive manufacturing techniques and materials and for correlating bulk microstructure properties to manufacturing process parameters. Additionally, the experimental strain distribution can help validate finite element models which many industries use to predict the residual stress distributions in additive manufactured components.« less

  13. Investigation of microstructure in additive manufactured Inconel 625 by spatially resolved neutron transmission spectroscopy

    PubMed Central

    Tremsin, Anton S.; Gao, Yan; Dial, Laura C.; Grazzi, Francesco; Shinohara, Takenao

    2016-01-01

    Abstract Non-destructive testing techniques based on neutron imaging and diffraction can provide information on the internal structure of relatively thick metal samples (up to several cm), which are opaque to other conventional non-destructive methods. Spatially resolved neutron transmission spectroscopy is an extension of traditional neutron radiography, where multiple images are acquired simultaneously, each corresponding to a narrow range of energy. The analysis of transmission spectra enables studies of bulk microstructures at the spatial resolution comparable to the detector pixel. In this study we demonstrate the possibility of imaging (with ~100 μm resolution) distribution of some microstructure properties, such as residual strain, texture, voids and impurities in Inconel 625 samples manufactured with an additive manufacturing method called direct metal laser melting (DMLM). Although this imaging technique can be implemented only in a few large-scale facilities, it can be a valuable tool for optimization of additive manufacturing techniques and materials and for correlating bulk microstructure properties to manufacturing process parameters. In addition, the experimental strain distribution can help validate finite element models which many industries use to predict the residual stress distributions in additive manufactured components. PMID:27877885

  14. Additive Technology: Update on Current Materials and Applications in Dentistry.

    PubMed

    Barazanchi, Abdullah; Li, Kai Chun; Al-Amleh, Basil; Lyons, Karl; Waddell, J Neil

    2017-02-01

    Additive manufacturing or 3D printing is becoming an alternative to subtractive manufacturing or milling in the area of computer-aided manufacturing. Research on material for use in additive manufacturing is ongoing, and a wide variety of materials are being used or developed for use in dentistry. Some materials, however, such as cobalt chromium, still lack sufficient research to allow definite conclusions about the suitability of their use in clinical dental practice. Despite this, due to the wide variety of machines that use additive manufacturing, there is much more flexibility in the build material and geometry when building structures compared with subtractive manufacturing. Overall additive manufacturing produces little material waste and is energy efficient when compared to subtractive manufacturing, due to passivity and the additive layering nature of the build process. Such features make the technique suitable to be used with fabricating structures out of hard to handle materials such as cobalt chromium. The main limitations of this technology include the appearance of steps due to layering of material and difficulty in fabricating certain material generally used in dentistry for use in 3D printing such as ceramics. The current pace of technological development, however, promises exciting possibilities. © 2016 by the American College of Prosthodontists.

  15. APPROACHES TO GEOMETRIC DATA ANALYSIS ON BIG AREA ADDITIVELY MANUFACTURED (BAAM) PARTS

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dreifus, Gregory D; Ally, Nadya R; Post, Brian K

    The promise of additive manufacturing is that a user can design and print complex geometries that are very difficult, if not impossible, to machine. The capabilities of 3D printing are restricted by a number of factors, including properties of the build material, time constraints, and geometric design restrictions. In this paper, a thorough accounting and study of the geometric restrictions that exist in the current iteration of additive manufacturing (AM) fused deposition modeling (FDM) technologies are discussed. Offline and online methodologies for collecting data sets for qualitative analysis of large scale AM, in particular Oak Ridge National Laboratory s (ORNL)more » big area additive manufacturing (BAAM) system, are summarized. In doing so, a survey of tools for designers and software developers is provided. In particular, strategies in which geometric data can be used as training sets for smarter AM technologies in the future are explained as well.« less

  16. IN718 Additive Manufacturing Properties and Influences

    NASA Technical Reports Server (NTRS)

    Lambert, Dennis M.

    2015-01-01

    The results of tensile, fracture, and fatigue testing of IN718 coupons produced using the selective laser melting (SLM) additive manufacturing technique are presented. The data has been "generalized" to remove the numerical values, although certain references to material standards are provided. This document provides some knowledge of the effect of variation of controlled build parameters used in the SLM process, a snapshot of the capabilities of SLM in industry at present, and shares some of the lessons learned along the way. For the build parameter characterization, the parameters were varied over a range about the machine manufacturer's recommended value, and in each case they were varied individually, although some co-variance of those parameters would be expected. SLM-produced IN718, tensile, fracture, and high-cycle fatigue properties equivalent to wrought IN718 are achievable. Build and post-build processes need to be determined and then controlled to established limits to accomplish this. It is recommended that a multi-variable evaluation, e.g., design-of-experiment (DOE), of the build parameters be performed to better evaluate the co-variance of the parameters.

  17. Low-cost Electromagnetic Heating Technology for Polymer Extrusion-based Additive Manufacturing

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Carter, William G.; Rios, Orlando; Akers, Ronald R.

    To improve the flow of materials used in in polymer additive manufacturing, ORNL and Ajax Tocco created an induction system for heating fused deposition modeling (FDM) nozzles used in polymer additive manufacturing. The system is capable of reaching a temperature of 230 C, a typical nozzle temperature for extruding ABS polymers, in 17 seconds. A prototype system was built at ORNL and sent to Ajax Tocco who analyzed the system and created a finalized power supply. The induction system was mounted to a PrintSpace Altair desktop printer and used to create several test parts similar in quality to those createdmore » using a resistive heated nozzle.« less

  18. Evaluation of an Al-Ce alloy for laser additive manufacturing

    DOE PAGES

    Plotkowski, A.; Rios, O.; Sridharan, N.; ...

    2016-12-27

    Our present research in metal additive manufacturing (AM) focuses on designing processing parameters around existing alloys designed for traditional manufacturing. However, to maximize the benefits of AM, alloys should be designed to specifically take advantage of the unique thermal conditions of these processes. Furthermore, our study focuses on the development of a design methodology for alloys in AM, using a newly developed Al-Ce alloy as an initial case study. To evaluate the candidacy of this system for fusion based additive manufacturing, single-line laser melts were made on cast Al-12Ce plates using three different beam velocities (100, 200, and 300 mm/min).more » The microstructure was evaluated in the as-melted and heat treated conditions (24 hrs at 300°C). An extremely fine microstructure was observed within the weld pools, evolving from eutectic at the outer solid-liquid boundaries to a primary Al FCC dendritic/cellular structure nearer the melt-pool centerline. We rationalized the observed microstructures through the construction of a microstructure selection map for the Al-Ce binary system, which will be used to enable future alloy design. Interestingly, the heat treated samples exhibited no microstructural coarsening.« less

  19. A Fully Non-metallic Gas Turbine Engine Enabled by Additive Manufacturing

    NASA Technical Reports Server (NTRS)

    Grady, Joseph E.

    2014-01-01

    The Non-Metallic Gas Turbine Engine project, funded by NASA Aeronautics Research Institute (NARI), represents the first comprehensive evaluation of emerging materials and manufacturing technologies that will enable fully nonmetallic gas turbine engines. This will be achieved by assessing the feasibility of using additive manufacturing technologies for fabricating polymer matrix composite (PMC) and ceramic matrix composite (CMC) gas turbine engine components. The benefits of the proposed effort include: 50 weight reduction compared to metallic parts, reduced manufacturing costs due to less machining and no tooling requirements, reduced part count due to net shape single component fabrication, and rapid design change and production iterations. Two high payoff metallic components have been identified for replacement with PMCs and will be fabricated using fused deposition modeling (FDM) with high temperature capable polymer filaments. The first component is an acoustic panel treatment with a honeycomb structure with an integrated back sheet and perforated front sheet. The second component is a compressor inlet guide vane. The CMC effort, which is starting at a lower technology readiness level, will use a binder jet process to fabricate silicon carbide test coupons and demonstration articles. The polymer and ceramic additive manufacturing efforts will advance from monolithic materials toward silicon carbide and carbon fiber reinforced composites for improved properties. Microstructural analysis and mechanical testing will be conducted on the PMC and CMC materials. System studies will assess the benefits of fully nonmetallic gas turbine engine in terms of fuel burn, emissions, reduction of part count, and cost. The proposed effort will be focused on a small 7000 lbf gas turbine engine. However, the concepts are equally applicable to large gas turbine engines. The proposed effort includes a multidisciplinary, multiorganization NASA - industry team that includes experts in

  20. K-9 training aids made using additive manufacturing

    DOEpatents

    Reynolds, John G.; Durban, Matthew M.; Gash, Alexander E.; Grapes, Michael D.; Kelley, Ryan S.; Sullivan, Kyle T.

    2018-02-20

    Additive Manufacturing (AM) is used to make aids that target the training of K-9s to detect explosives. The process uses mixtures of explosives and matrices commonly used in AM. The explosives are formulated into a mixture with the matrix and printed using AM techniques and equipment. The explosive concentrations are kept less than 10% by wt. of the mixture to conform to requirements of shipping and handling.

  1. Characterization of an Additive Manufactured TiAl Alloy—Steel Joint Produced by Electron Beam Welding

    PubMed Central

    Baudana, Giorgio; Lorusso, Massimo; Ugues, Daniele; Fino, Paolo

    2018-01-01

    In this work, the characterization of the assembly of a steel shaft into a γ-TiAl part for turbocharger application, obtained using Electron Beam Welding (EBW) technology with a Ni-based filler, was carried out. The Ti-48Al-2Nb-0.7Cr-0.3Si (at %) alloy part was produced by Electron Beam Melting (EBM). This additive manufacturing technology allows the production of a lightweight part with complex shapes. The replacement of Nickel-based superalloys with TiAl alloys in turbocharger automotive applications will lead to an improvement of the engine performance and a substantial reduction in fuel consumption and emission. The welding process allows a promising joint to be obtained, not affecting the TiAl microstructure. Nevertheless, it causes the formation of diffusive layers between the Ni-based filler and both steel and TiAl, with the latter side being characterized by a very complex microstructure, which was fully characterized in this paper by means of Scanning Electron Microscopy, Energy Dispersive X-ray Spectroscopy, and nanoindentation. The diffusive interface has a thickness of about 6 µm, and it is composed of several layers. Specifically, from the TiAl alloy side, we find a layer of Ti3Al followed by Al3NiTi2 and AlNi2Ti. Subsequently Ni becomes more predominant, with a first layer characterized by abundant carbide/boride precipitation, and a second layer characterized by Si-enrichment. Then, the chemical composition of the Ni-based filler is gradually reached. PMID:29342074

  2. Additive manufacturing of poly[(R)-3-hydroxybutyrate-co-(R)-3-hydroxyhexanoate] scaffolds for engineered bone development.

    PubMed

    Mota, Carlos; Wang, Shen-Yu; Puppi, Dario; Gazzarri, Matteo; Migone, Chiara; Chiellini, Federica; Chen, Guo-Qiang; Chiellini, Emo

    2017-01-01

    A wide range of poly(hydroxyalkanoate)s (PHAs), a class of biodegradable polyesters produced by various bacteria grown under unbalanced conditions, have been proposed for the fabrication of tissue-engineering scaffolds. In this study, the manufacture of poly[(R)-3-hydroxybutyrate-co-(R)-3-hydroxyhexanoate] (or PHBHHx) scaffolds, by means of an additive manufacturing technique based on a computer-controlled wet-spinning system, was investigated. By optimizing the processing parameters, three-dimensional scaffolds with different internal architectures were fabricated, based on a layer-by-layer approach. The resulting scaffolds were characterized by scanning electron microscopy, which showed good control over the fibre alignment and a fully interconnected porous network, with porosity in the range 79-88%, fibre diameter 47-76 µm and pore size 123-789 µm. Moreover, the resulting fibres presented an internal porosity connected to the external fibre surface as a consequence of the phase-inversion process governing the solidification of the polymer solution. Scaffold compressive modulus and yield stress and strain could be varied in a certain range by changing the architectural parameters. Cell-culture experiments employing the MC3T3-E1 murine pre-osteoblast cell line showed good cell proliferation after 21 days of culture. The PHBHHx scaffolds demonstrated promising results in terms of cell differentiation towards an osteoblast phenotype. Copyright © 2014 John Wiley & Sons, Ltd. Copyright © 2014 John Wiley & Sons, Ltd.

  3. Additive Manufacturing Modeling and Simulation A Literature Review for Electron Beam Free Form Fabrication

    NASA Technical Reports Server (NTRS)

    Seufzer, William J.

    2014-01-01

    Additive manufacturing is coming into industrial use and has several desirable attributes. Control of the deposition remains a complex challenge, and so this literature review was initiated to capture current modeling efforts in the field of additive manufacturing. This paper summarizes about 10 years of modeling and simulation related to both welding and additive manufacturing. The goals were to learn who is doing what in modeling and simulation, to summarize various approaches taken to create models, and to identify research gaps. Later sections in the report summarize implications for closed-loop-control of the process, implications for local research efforts, and implications for local modeling efforts.

  4. Solidification and solid-state transformation sciences in metals additive manufacturing

    DOE PAGES

    Kirka, Michael M.; Nandwana, Peeyush; Lee, Yousub; ...

    2017-02-11

    Additive manufacturing (AM) of metals is rapidly emerging as an established manufacturing process for metal components. Unlike traditional metals fabrication processes, metals fabricated via AM undergo localized thermal cycles during fabrication. As a result, AM presents the opportunity to control the liquid-solid phase transformation, i.e. material texture. But, thermal cycling presents challenges from the standpoint of solid-solid phase transformations. We will discuss the opportunities and challenges in metals AM in the context of texture control and associated solid-solid phase transformations in Ti-6Al-4V and Inconel 718.

  5. Design of an Orthopedic Product by Using Additive Manufacturing Technology: The Arm Splint.

    PubMed

    Blaya, Fernando; Pedro, Pilar San; Silva, Julia López; D'Amato, Roberto; Heras, Enrique Soriano; Juanes, Juan Antonio

    2018-02-05

    The traditional fabrication process of custom-made splints has hardly undergone any progress since the beginning of its use at the end of the eighteenth century. New manufacturing techniques and the new materials can help to modernize this treatment method of fractures. The use of Additive Manufacturing has been proposed in recent years as an alternative process for the manufacture of splints and there has been an increase in public awareness and exploration. For this reason, in this study a splint model printed in 3D, that replaces the deficiencies of the cast maintaining its virtues, has been proposed. The proposed methodology is based on three-dimensional digitalization techniques and 3D modeling with reverse engineering software. The work integrates different scientific disciplines to achieve its main goal: to improve life quality of the patient. In addition, the splint has been designed based on the principles of sustainable development. The design of splint is made of Polycarbonate by technique of Additive Manufacturing with fused deposition manufacturing, and conceived with organic shapes, customizing openings and closing buttons with rubber. In this preliminary study the final result is a prototype of the 3D printed arm splint in a reduced scale by using PLA as material.

  6. SLM processing-microstructure-mechanical property correlation in an aluminum alloy produced by additive manufacturing

    NASA Astrophysics Data System (ADS)

    Alejos, Martin Fernando

    Additive manufacturing has become a highly researched topic in recent years all over the world. The current research evaluates the merits of additive manufacturing based on the mechanical, microstructural, and fracture properties of additive manufactured AlSi10Mg test specimens. The additive manufactured build plates consisted of tensile and fatigue test specimens. They were printed in the 0°, 30°, 60°, and 90° orientations relative to the build platform. Tensile and dynamic fatigue tests were conducted followed by microstructural characterization and fracture analysis. A wrought 6061 T6 aluminum alloy was also tested for comparison. Tensile tests revealed similar ultimate tensile strengths for all aluminum tensile specimens (350-380 MPa). Fatigue strength was greatest for wrought 6061 T6 aluminum (175 MPa). The fatigue behavior was a strong function of build orientation for the additive manufactured specimens. The 0°, 30°, and 60° orientations had fatigue strengths close to 104 MPa while the 90° orientation had a fatigue strength of 125 MPa. All test specimens failed primarily in a ductile manner. The effect of laser power, hatch spacing, and scan speed were also studied using microstructural analysis. Increasing laser power decreased grain size and void size. Increasing scan speed led to the formation of columnar grains. Increasing hatch spacing decreased grain size and the amount of voids present in the microstructure.

  7. Additive Manufacturing of Thermoplastic Matrix Composites Using Ultrasonics

    NASA Astrophysics Data System (ADS)

    Olson, Meghan

    Advanced composite materials have great potential for facilitating energy efficient product design and their manufacture if improvements are made to current composite manufacturing processes. This thesis focuses on the development of a novel manufacturing process for thermoplastic composite structures entitled Laser-Ultrasonic Additive Manufacturing ('LUAM'), which is intended to combine the benefits of laser processing technology, developed by Automated Dynamics Inc., with ultrasonic bonding technology that is used commercially for unreinforced polymers. These technologies used together have the potential to significantly reduce the energy consumption and void content of thermoplastic composites made using Automated Fiber Placement (AFP). To develop LUAM in a methodical manner with minimal risk, a staged approach was devised whereby coupon-level mechanical testing and prototyping utilizing existing equipment was accomplished. Four key tasks have been identified for this effort: Benchmarking, Ultrasonic Compaction, Laser Assisted Ultrasonic Compaction, and Demonstration and Characterization of LUAM. This thesis specifically addresses Tasks 1 and 2, i.e. Benchmarking and Ultrasonic Compaction, respectively. Task 1, fabricating test specimens using two traditional processes (autoclave and thermal press) and testing structural performance and dimensional accuracy, provide results of a benchmarking study by which the performance of all future phases will be gauged. Task 2, fabricating test specimens using a non-traditional process (ultrasonic conpaction) and evaluating in a similar fashion, explores the the role of ultrasonic processing parameters using three different thermoplastic composite materials. Further development of LUAM, although beyond the scope of this thesis, will combine laser and ultrasonic technology and eventually demonstrate a working system.

  8. America Makes: The National Additive Manufacturing Innovation Institute (NAMII) Status Report and Future Opportunities (Postprint)

    DTIC Science & Technology

    2014-09-01

    manufacturing, direct part manufacturing, manufacturing institute, public- private partnership, rapid manufacturing, 3D printing 16. SECURITY CLASSIFICATION...Manufacturing Science and Technology Pro- gram and selected Additive Manufacturing (or more popularly known as 3D printing ) as the technical subject. Working...operations, America Makes is starting to hit its stride in developing technology for 3D printing and in leading the way in how the United States should

  9. Mechanical Properties of Austenitic Stainless Steel Made by Additive Manufacturing

    PubMed Central

    Luecke, William E; Slotwinski, John A

    2014-01-01

    Using uniaxial tensile and hardness testing, we evaluated the variability and anisotropy of the mechanical properties of an austenitic stainless steel, UNS S17400, manufactured by an additive process, selective laser melting. Like wrought materials, the mechanical properties depend on the orientation introduced by the processing. The recommended stress-relief heat treatment increases the tensile strength, reduces the yield strength, and decreases the extent of the discontinuous yielding. The mechanical properties, assessed by hardness, are very uniform across the build plate, but the stress-relief heat treatment introduced a small non-uniformity that had no correlation to position on the build plate. Analysis of the mechanical property behavior resulted in four conclusions. (1) The within-build and build-to-build tensile properties of the UNS S17400 stainless steel are less repeatable than mature engineering structural alloys, but similar to other structural alloys made by additive manufacturing. (2) The anisotropy of the mechanical properties of the UNS S17400 material of this study is larger than that of mature structural alloys, but is similar to other structural alloys made by additive manufacturing. (3) The tensile mechanical properties of the UNS S17400 material fabricated by selective laser melting are very different from those of wrought, heat-treated 17-4PH stainless steel. (4) The large discontinuous yielding strain in all tests resulted from the formation and propagation of Lüders bands. PMID:26601037

  10. Machinability of Al 6061 Deposited with Cold Spray Additive Manufacturing

    NASA Astrophysics Data System (ADS)

    Aldwell, Barry; Kelly, Elaine; Wall, Ronan; Amaldi, Andrea; O'Donnell, Garret E.; Lupoi, Rocco

    2017-10-01

    Additive manufacturing techniques such as cold spray are translating from research laboratories into more mainstream high-end production systems. Similar to many additive processes, finishing still depends on removal processes. This research presents the results from investigations into aspects of the machinability of aluminum 6061 tubes manufactured with cold spray. Through the analysis of cutting forces and observations on chip formation and surface morphology, the effect of cutting speed, feed rate, and heat treatment was quantified, for both cold-sprayed and bulk aluminum 6061. High-speed video of chip formation shows changes in chip form for varying material and heat treatment, which is supported by the force data and quantitative imaging of the machined surface. The results shown in this paper demonstrate that parameters involved in cold spray directly impact on machinability and therefore have implications for machining parameters and strategy.

  11. Embedding Carbon Fibre Structures in Metal Matrixes for Additive Manufacturing

    NASA Astrophysics Data System (ADS)

    Frostevarg, Jan; Robertson, Stephanie; Benavides, Vicente; Soldatov, Alexander

    It is possible to reinforce structures and components using carbon fibres for applications in electronics and medicine, but most commonly used in reinforcing resin fibre composites for personal protection equipment and light weight constructions. Carbon fibres act as stress redistributors while having increased electrical and thermal conductivities. These properties could also be utilized in metal matrixes, if the fibres are properly fused to the metal and the structure remains intact. Another recently developed high potential carbon structure, carbon nanotube- (CNT) yarns, has similar but even greater mechanical properties than common carbon fibres. Via laser cladding, these reinforcing materials could be used in a plethora of applications, either locally (or globally) as surface treatments or as structural reinforcements using multi-layer laser cladding (additive manufacturing). The challenges of embedding carbon fibres or CNT-yarns in a CuAl mixture and SnPb solder wire using lasers are here investigated using high speed imaging and SEM. It is revealed that the carbon fibres have very high buoyancy in the molten metal and quickly degrades when irradiated by the laser. Wetting of the fibres is shown to be improved by a Tungsten coating and embedding of the structures after processing are evaluated using SEM and Raman spectroscopy.

  12. Infrared Preheating to Enhance Interlayer Strength of Components Printed on the Big Area Additive Manufacturing (BAAM) System

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kishore, Vidya; Ajinjeru, Christine; Duty, Chad E

    The Big Area Additive Manufacturing (BAAM) system has the capacity to print structures on the order of several meters at a rate exceeding 50 kg/h, thereby having the potential to significantly impact the production of components in automotive, aerospace and energy sectors. However, a primary issue that limits the functional use of such parts is mechanical anisotropy. The strength of printed parts across successive layers in the build direction (z-direction) is significantly lower than the corresponding in-plane strength (x-y directions). This is largely due to poor bonding between the printed layers as the lower layers cool below the glass transitionmore » temperature (Tg) before the next layer is deposited. This work explores the use of infrared heating to increase the surface temperature of the printed layer just prior to deposition of new material to improve the interlayer strength of the components. The material used in this study was acrylonitrile butadiene styrene (ABS) reinforced with 20% chopped carbon fiber by weight. Significant improvements in z-strength were observed for the parts whose surface temperature was increased from below Tg to close to or above Tg using infrared heating. Parameters such as print speed, nozzle diameter and extrusion temperature were also found to impact the heat input required to enhance interlayer adhesion without significantly degrading the polymer and compromising on surface finish.« less

  13. Additive Manufacturing in Offsite Repair of Consumer Electronics

    NASA Astrophysics Data System (ADS)

    Chekurov, Sergei; Salmi, Mika

    Spare parts for products that are at the end of their life cycles, but still under warranty, are logistically difficult because they are commonly not stored in the central warehouse. These uncommon spare parts occupy valuable space in smaller inventories and take a long time to be transported to the point of need, thus delaying the repair process. This paper proposes that storing the spare parts on a server and producing them with additive manufacturing (AM) on demand can shorten the repair cycle by simplifying the logistics. Introducing AM in the repair supply chain lowers the number of products that need to be reimbursed to the customer due to lengthy repairs, improves the repair statistics of the repair shops, and reduces the number of items that are held in stock. For this paper, the functionality of the concept was verified by reverse engineering a memory cover of a portable computer and laser sintering it from polyamide 12. The additively manufactured component fit well and the computer operated normally after the replacement. The current spare part supply chain model and models with AM machinery located at the repair shop, the centralized spare part provider, and the original equipment manufacturer were provided. The durations of the repair process in the models were compared by simulating two scenarios with the Monte Carlo method. As the biggest improvement, the model with the AM machine in the repair shop reduced the duration of the repair process from 14 days to three days. The result points to the conclusion that placing the machine as close to the need as possible is the best option, if there is enough demand. The spare parts currently compatible with AM are plastic components without strict surface roughness requirements, but more spare parts will become compatible with the development of AM.

  14. Review on Advances of Functional Material for Additive Manufacturing

    NASA Astrophysics Data System (ADS)

    Zulkifli, Nur Amalina Binti; Akmal Johar, Muhammad; Faizan Marwah, Omar Mohd; Irwan Ibrahim, Mohd Halim

    2017-08-01

    The attempt of finding and making new materials in improving products that are already in the market are widely done by researchers nowadays. This project is focusing on making new materials for functional material through additive manufacturing application. The idea of this project came from the ability limitation of capacitor in market nowadays in storing higher charges but smaller in size. Powder glass is the new material that could to be used as a dielectric material for capacitor with the help of palm kernel oil as the binder. This paper reviews on applications done through additive manufacturing method and also types of functional materials used in this method previously. Structure of a capacitor, dielectric properties and measurement techniques that are trying to be carried out are also explains in this paper. Last part of this paper brief on the material proposal and reasons those materials are chosen. New dielectric material for capacitor which are able to store more charges but still small in size are expected to be produced as the outcome of this research.

  15. Additive Manufacturing Processes: Selective Laser Melting, Electron Beam Melting and Binder Jetting—Selection Guidelines

    PubMed Central

    Konda Gokuldoss, Prashanth; Kolla, Sri; Eckert, Jürgen

    2017-01-01

    Additive manufacturing (AM), also known as 3D printing or rapid prototyping, is gaining increasing attention due to its ability to produce parts with added functionality and increased complexities in geometrical design, on top of the fact that it is theoretically possible to produce any shape without limitations. However, most of the research on additive manufacturing techniques are focused on the development of materials/process parameters/products design with different additive manufacturing processes such as selective laser melting, electron beam melting, or binder jetting. However, we do not have any guidelines that discuss the selection of the most suitable additive manufacturing process, depending on the material to be processed, the complexity of the parts to be produced, or the design considerations. Considering the very fact that no reports deal with this process selection, the present manuscript aims to discuss the different selection criteria that are to be considered, in order to select the best AM process (binder jetting/selective laser melting/electron beam melting) for fabricating a specific component with a defined set of material properties. PMID:28773031

  16. Additive Manufacturing Processes: Selective Laser Melting, Electron Beam Melting and Binder Jetting-Selection Guidelines.

    PubMed

    Gokuldoss, Prashanth Konda; Kolla, Sri; Eckert, Jürgen

    2017-06-19

    Additive manufacturing (AM), also known as 3D printing or rapid prototyping, is gaining increasing attention due to its ability to produce parts with added functionality and increased complexities in geometrical design, on top of the fact that it is theoretically possible to produce any shape without limitations. However, most of the research on additive manufacturing techniques are focused on the development of materials/process parameters/products design with different additive manufacturing processes such as selective laser melting, electron beam melting, or binder jetting. However, we do not have any guidelines that discuss the selection of the most suitable additive manufacturing process, depending on the material to be processed, the complexity of the parts to be produced, or the design considerations. Considering the very fact that no reports deal with this process selection, the present manuscript aims to discuss the different selection criteria that are to be considered, in order to select the best AM process (binder jetting/selective laser melting/electron beam melting) for fabricating a specific component with a defined set of material properties.

  17. Mechanical Properties of Additively Manufactured Thick Honeycombs.

    PubMed

    Hedayati, Reza; Sadighi, Mojtaba; Mohammadi Aghdam, Mohammad; Zadpoor, Amir Abbas

    2016-07-23

    Honeycombs resemble the structure of a number of natural and biological materials such as cancellous bone, wood, and cork. Thick honeycomb could be also used for energy absorption applications. Moreover, studying the mechanical behavior of honeycombs under in-plane loading could help understanding the mechanical behavior of more complex 3D tessellated structures such as porous biomaterials. In this paper, we study the mechanical behavior of thick honeycombs made using additive manufacturing techniques that allow for fabrication of honeycombs with arbitrary and precisely controlled thickness. Thick honeycombs with different wall thicknesses were produced from polylactic acid (PLA) using fused deposition modelling, i.e., an additive manufacturing technique. The samples were mechanically tested in-plane under compression to determine their mechanical properties. We also obtained exact analytical solutions for the stiffness matrix of thick hexagonal honeycombs using both Euler-Bernoulli and Timoshenko beam theories. The stiffness matrix was then used to derive analytical relationships that describe the elastic modulus, yield stress, and Poisson's ratio of thick honeycombs. Finite element models were also built for computational analysis of the mechanical behavior of thick honeycombs under compression. The mechanical properties obtained using our analytical relationships were compared with experimental observations and computational results as well as with analytical solutions available in the literature. It was found that the analytical solutions presented here are in good agreement with experimental and computational results even for very thick honeycombs, whereas the analytical solutions available in the literature show a large deviation from experimental observation, computational results, and our analytical solutions.

  18. Mechanical Properties of Additively Manufactured Thick Honeycombs

    PubMed Central

    Hedayati, Reza; Sadighi, Mojtaba; Mohammadi Aghdam, Mohammad; Zadpoor, Amir Abbas

    2016-01-01

    Honeycombs resemble the structure of a number of natural and biological materials such as cancellous bone, wood, and cork. Thick honeycomb could be also used for energy absorption applications. Moreover, studying the mechanical behavior of honeycombs under in-plane loading could help understanding the mechanical behavior of more complex 3D tessellated structures such as porous biomaterials. In this paper, we study the mechanical behavior of thick honeycombs made using additive manufacturing techniques that allow for fabrication of honeycombs with arbitrary and precisely controlled thickness. Thick honeycombs with different wall thicknesses were produced from polylactic acid (PLA) using fused deposition modelling, i.e., an additive manufacturing technique. The samples were mechanically tested in-plane under compression to determine their mechanical properties. We also obtained exact analytical solutions for the stiffness matrix of thick hexagonal honeycombs using both Euler-Bernoulli and Timoshenko beam theories. The stiffness matrix was then used to derive analytical relationships that describe the elastic modulus, yield stress, and Poisson’s ratio of thick honeycombs. Finite element models were also built for computational analysis of the mechanical behavior of thick honeycombs under compression. The mechanical properties obtained using our analytical relationships were compared with experimental observations and computational results as well as with analytical solutions available in the literature. It was found that the analytical solutions presented here are in good agreement with experimental and computational results even for very thick honeycombs, whereas the analytical solutions available in the literature show a large deviation from experimental observation, computational results, and our analytical solutions. PMID:28773735

  19. Microstructures and Grain Refinement of Additive-Manufactured Ti- xW Alloys

    NASA Astrophysics Data System (ADS)

    Mendoza, Michael Y.; Samimi, Peyman; Brice, David A.; Martin, Brian W.; Rolchigo, Matt R.; LeSar, Richard; Collins, Peter C.

    2017-07-01

    It is necessary to better understand the composition-processing-microstructure relationships that exist for materials produced by additive manufacturing. To this end, Laser Engineered Net Shaping (LENS™), a type of additive manufacturing, was used to produce a compositionally graded titanium binary model alloy system (Ti- xW specimen (0 ≤ x ≤ 30 wt pct), so that relationships could be made between composition, processing, and the prior beta grain size. Importantly, the thermophysical properties of the Ti- xW, specifically its supercooling parameter ( P) and growth restriction factor ( Q), are such that grain refinement is expected and was observed. The systematic, combinatorial study of this binary system provides an opportunity to assess the mechanisms by which grain refinement occurs in Ti-based alloys in general, and for additive manufacturing in particular. The operating mechanisms that govern the relationship between composition and grain size are interpreted using a model originally developed for aluminum and magnesium alloys and subsequently applied for titanium alloys. The prior beta grain factor observed and the interpretations of their correlations indicate that tungsten is a good grain refiner and such models are valid to explain the grain-refinement process. By extension, other binary elements or higher order alloy systems with similar thermophysical properties should exhibit similar grain refinement.

  20. Structural Color for Additive Manufacturing: 3D-Printed Photonic Crystals from Block Copolymers.

    PubMed

    Boyle, Bret M; French, Tracy A; Pearson, Ryan M; McCarthy, Blaine G; Miyake, Garret M

    2017-03-28

    The incorporation of structural color into 3D printed parts is reported, presenting an alternative to the need for pigments or dyes for colored parts produced through additive manufacturing. Thermoplastic build materials composed of dendritic block copolymers were designed, synthesized, and used to additively manufacture plastic parts exhibiting structural color. The reflection properties of the photonic crystals arise from the periodic nanostructure formed through block copolymer self-assembly during polymer processing. The wavelength of reflected light could be tuned across the visible spectrum by synthetically controlling the block copolymer molecular weight and manufacture parts that reflected violet, green, or orange light with the capacity to serve as selective optical filters and light guides.

  1. Analysis of variability in additive manufactured open cell porous structures.

    PubMed

    Evans, Sam; Jones, Eric; Fox, Pete; Sutcliffe, Chris

    2017-06-01

    In this article, a novel method of analysing build consistency of additively manufactured open cell porous structures is presented. Conventionally, methods such as micro computed tomography or scanning electron microscopy imaging have been applied to the measurement of geometric properties of porous material; however, high costs and low speeds make them unsuitable for analysing high volumes of components. Recent advances in the image-based analysis of open cell structures have opened up the possibility of qualifying variation in manufacturing of porous material. Here, a photogrammetric method of measurement, employing image analysis to extract values for geometric properties, is used to investigate the variation between identically designed porous samples measuring changes in material thickness and pore size, both intra- and inter-build. Following the measurement of 125 samples, intra-build material thickness showed variation of ±12%, and pore size ±4% of the mean measured values across five builds. Inter-build material thickness and pore size showed mean ranges higher than those of intra-build, ±16% and ±6% of the mean material thickness and pore size, respectively. Acquired measurements created baseline variation values and demonstrated techniques suitable for tracking build deviation and inspecting additively manufactured porous structures to indicate unwanted process fluctuations.

  2. Enhancing current-induced torques by abutting additional spin polarizer layer to nonmagnetic metal layer

    NASA Astrophysics Data System (ADS)

    Go, Gyungchoon; Lee, Kyung-Jin; Kim, Young Keun

    2017-04-01

    Recently, the switching of a perpendicularly magnetized ferromagnet (FM) by injecting an in-plane current into an attached non-magnet (NM) has become of emerging technological interest. This magnetization switching is attributed to the spin-orbit torque (SOT) originating from the strong spin-orbit coupling of the NM layer. However, the switching efficiency of the NM/FM structure itself may be insufficient for practical use, as for example, in spin transfer torque (STT)-based magnetic random access memory (MRAM) devices. Here we investigate spin torque in an NM/FM structure with an additional spin polarizer (SP) layer abutted to the NM layer. In addition to the SOT contribution, a spin-polarized current from the SP layer creates an extra spin chemical potential difference at the NM/FM interface and gives rise to a STT on the FM layer. We show that, using typical parameters including device width, thickness, spin diffusion length, and the spin Hall angle, the spin torque from the SP layer can be much larger than that from the spin Hall effect (SHE) of the NM.

  3. IN718 Additive Manufacturing Properties and Influences

    NASA Technical Reports Server (NTRS)

    Lambert, Dennis M.

    2015-01-01

    The results of tensile, fracture, and fatigue testing of IN718 coupons produced using the selective laser melting (SLM) additive manufacturing technique are presented. The data have been "sanitized" to remove the numerical values, although certain references to material standards are provided. This document provides some knowledge of the effect of variation of controlled build parameters used in the SLM process, a snapshot of the capabilities of SLM in industry at present, and shares some of the lessons learned along the way. For the build parameter characterization, the parameters were varied over a range that was centered about the machine manufacturer's recommended value, and in each case they were varied individually, although some co-variance of those parameters would be expected. Tensile, fracture, and high-cycle fatigue properties equivalent to wrought IN718 are achievable with SLM-produced IN718. Build and post-build processes need to be determined and then controlled to established limits to accomplish this. It is recommended that a multi-variable evaluation, e.g., design-of experiment (DOE), of the build parameters be performed to better evaluate the co-variance of the parameters.

  4. The accuracy of ultrashort echo time MRI sequences for medical additive manufacturing

    PubMed Central

    Rijkhorst, Erik-Jan; Hofman, Mark; Forouzanfar, Tymour; Wolff, Jan

    2016-01-01

    Objectives: Additively manufactured bone models, implants and drill guides are becoming increasingly popular amongst maxillofacial surgeons and dentists. To date, such constructs are commonly manufactured using CT technology that induces ionizing radiation. Recently, ultrashort echo time (UTE) MRI sequences have been developed that allow radiation-free imaging of facial bones. The aim of the present study was to assess the feasibility of UTE MRI sequences for medical additive manufacturing (AM). Methods: Three morphologically different dry human mandibles were scanned using a CT and MRI scanner. Additionally, optical scans of all three mandibles were made to acquire a “gold standard”. All CT and MRI scans were converted into Standard Tessellation Language (STL) models and geometrically compared with the gold standard. To quantify the accuracy of the AM process, the CT, MRI and gold-standard STL models of one of the mandibles were additively manufactured, optically scanned and compared with the original gold-standard STL model. Results: Geometric differences between all three CT-derived STL models and the gold standard were <1.0 mm. All three MRI-derived STL models generally presented deviations <1.5 mm in the symphyseal and mandibular area. The AM process introduced minor deviations of <0.5 mm. Conclusions: This study demonstrates that MRI using UTE sequences is a feasible alternative to CT in generating STL models of the mandible and would therefore be suitable for surgical planning and AM. Further in vivo studies are necessary to assess the usability of UTE MRI sequences in clinical settings. PMID:26943179

  5. The accuracy of ultrashort echo time MRI sequences for medical additive manufacturing.

    PubMed

    van Eijnatten, Maureen; Rijkhorst, Erik-Jan; Hofman, Mark; Forouzanfar, Tymour; Wolff, Jan

    2016-01-01

    Additively manufactured bone models, implants and drill guides are becoming increasingly popular amongst maxillofacial surgeons and dentists. To date, such constructs are commonly manufactured using CT technology that induces ionizing radiation. Recently, ultrashort echo time (UTE) MRI sequences have been developed that allow radiation-free imaging of facial bones. The aim of the present study was to assess the feasibility of UTE MRI sequences for medical additive manufacturing (AM). Three morphologically different dry human mandibles were scanned using a CT and MRI scanner. Additionally, optical scans of all three mandibles were made to acquire a "gold standard". All CT and MRI scans were converted into Standard Tessellation Language (STL) models and geometrically compared with the gold standard. To quantify the accuracy of the AM process, the CT, MRI and gold-standard STL models of one of the mandibles were additively manufactured, optically scanned and compared with the original gold-standard STL model. Geometric differences between all three CT-derived STL models and the gold standard were <1.0 mm. All three MRI-derived STL models generally presented deviations <1.5 mm in the symphyseal and mandibular area. The AM process introduced minor deviations of <0.5 mm. This study demonstrates that MRI using UTE sequences is a feasible alternative to CT in generating STL models of the mandible and would therefore be suitable for surgical planning and AM. Further in vivo studies are necessary to assess the usability of UTE MRI sequences in clinical settings.

  6. Additively manufactured biodegradable porous magnesium.

    PubMed

    Li, Y; Zhou, J; Pavanram, P; Leeflang, M A; Fockaert, L I; Pouran, B; Tümer, N; Schröder, K-U; Mol, J M C; Weinans, H; Jahr, H; Zadpoor, A A

    2018-02-01

    . Recent advances in additive manufacturing have resulted in biomaterials that satisfy the first two requirements but simultaneously satisfying the third requirement has proven challenging so far. Here we present additively manufactured porous magnesium structures that have the potential to satisfy all above-mentioned requirements. Even after 4 weeks of biodegradation, the mechanical properties of the porous structures were found to be within those reported for native bone. Moreover, our comprehensive electrochemical, mechanical, topological, and biological study revealed a unique biodegradation behavior and the limited cytotoxicity of the developed biomaterials. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  7. Applications for Gradient Metal Alloys Fabricated Using Additive Manufacturing

    NASA Technical Reports Server (NTRS)

    Hofmann, Douglas C.; Borgonia, John Paul C.; Dillon, Robert P.; Suh, Eric J.; Mulder, jerry L.; Gardner, Paul B.

    2013-01-01

    Recently, additive manufacturing (AM) techniques have been developed that may shift the paradigm of traditional metal production by allowing complex net-shaped hardware to be built up layer-by-layer, rather than being machined from a billet. The AM process is ubiquitous with polymers due to their low melting temperatures, fast curing, and controllable viscosity, and 3D printers are widely available as commercial or consumer products. 3D printing with metals is inherently more complicated than with polymers due to their higher melting temperatures and reactivity with air, particularly when heated or molten. The process generally requires a high-power laser or other focused heat source, like an electron beam, for precise melting and deposition. Several promising metal AM techniques have been developed, including laser deposition (also called laser engineered net shaping or LENS® and laser deposition technology (LDT)), direct metal laser sintering (DMLS), and electron beam free-form (EBF). These machines typically use powders or wire feedstock that are melted and deposited using a laser or electron beam. Complex net-shape parts have been widely demonstrated using these (and other) AM techniques and the process appears to be a promising alternative to machining in some cases. Rather than simply competing with traditional machining for cost and time savings, the true advantage of AM involves the fabrication of hardware that cannot be produced using other techniques. This could include parts with "blind" features (like foams or trusses), parts that are difficult to machine conventionally, or parts made from materials that do not exist in bulk forms. In this work, the inventors identify that several AM techniques can be used to develop metal parts that change composition from one location in the part to another, allowing for complete control over the mechanical or physical properties. This changes the paradigm for conventional metal fabrication, which relies on an

  8. Additive Manufacturing and Characterization of Polylactic Acid (PLA) Composites Containing Metal Reinforcements

    NASA Technical Reports Server (NTRS)

    Kuentz, Lily; Salem, Anton; Singh, M.; Halbig, M. C.; Salem, J. A.

    2016-01-01

    Additive manufacturing of polymeric systems using 3D printing has become quite popular recently due to rapid growth and availability of low cost and open source 3D printers. Two widely used 3D printing filaments are based on polylactic acid (PLA) and acrylonitrile butadiene styrene (ABS) systems. PLA is much more environmentally friendly in comparison to ABS since it is made from renewable resources such as corn, sugarcane, and other starches as precursors. Recently, polylactic acid-based metal powder containing composite filaments have emerged which could be utilized for multifunctional applications. The composite filaments have higher density than pure PLA, and the majority of the materials volume is made up of polylactic acid. In order to utilize functionalities of composite filaments, printing behavior and properties of 3-D printed composites need to be characterized and compared with the pure PLA materials. In this study, pure PLA and composite specimens with different metallic reinforcements (Copper, Bronze, Tungsten, Iron, etc) were 3D printed at various layer heights and resulting microstructures and properties were characterized. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) behavior of filaments with different reinforcements were studied. The microscopy results show an increase in porosity between 3-D printed regular PLA and the metal composite PLA samples, which could produce weaker mechanical properties in the metal composite materials. Tensile strength and fracture toughness behavior of specimens as a function of print layer height will be presented.

  9. Nondestructive Testing of Additive Manufactured Metal Parts Used in Aerospace Applications

    NASA Technical Reports Server (NTRS)

    Waller, Jess M.

    2018-01-01

    NDE inspectors, QA/QE professionals, and program managers responsible for the out-sourcing, procurement, fabrication, finishing, inspection, and qualification and certification of additively manufactured (AM) parts should attend this course.

  10. Additively Manufactured, Net Shape Powder Metallurgy Cans for Valves Used in Energy Production

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Peter, William H.; Gandy, David; Lannom, Robert

    This CRADA NFE-14-05241 was conducted as a Technical Collaboration project within the Oak Ridge National Laboratory (ORNL) Manufacturing Demonstration Facility (MDF) sponsored by the US Department of Energy Advanced Manufacturing Office (CPS Agreement Number 24761). Opportunities for MDF technical collaborations are listed in the announcement “Manufacturing Demonstration Facility Technology Collaborations for US Manufacturers in Advanced Manufacturing and Materials Technologies” posted at http://web.ornl.gov/sci/manufacturing/docs/FBO-ORNL-MDF-2013-2.pdf. The goal of technical collaborations is to engage industry partners to participate in short-term, collaborative projects within the Manufacturing Demonstration Facility (MDF) to assess applicability and of new energy efficient manufacturing technologies. Research sponsored by the U.S. Departmentmore » of Energy, Office of Energy Efficiency and Renewable Energy, Advanced Manufacturing Office, under contract DE-AC05-00OR22725 with UT-Battelle, LLC.ORNL would like to acknowledge the leadership of EPRI in pulling together the extensive team and managing the execution of the project. In addition, ORNL would like to acknowledge the other contributions of the team members associated with this project. Quintus provided time, access, expertise, and labor of their hydro forming capabilities to evaluate both conventional and additively manufactured tools through this process. Crane ChemPharma Energy provided guidance and information on valve geometries. Carpenter Powder Products was involved with the team providing information on powder processing as it pertains to the canning and hot isostatic pressing of powder. on providing powder and knowledge as it pertains to powder supply for hot isostatic pressing; they also provided powder for the test trials by the industrial team. Bodycote provided guidance on hot isostatic pressing and can requirements. They were also responsible for the hot isostatic pressing of the test

  11. Expanding the Design Space: Forging the Transition from 3D Printing to Additive Manufacturing

    NASA Astrophysics Data System (ADS)

    Amend, Matthew

    The synergy of Additive Manufacturing and Computational Geometry has the potential to radically expand the "design space" of solutions available to designers. Additive Manufacturing (AM) is capable of fabricating objects that are highly complex both in geometry and material properties. However, the introduction of any new technology can have a disruptive effect on established design practices and organizations. Before "Design for Additive Manufacturing" (DFAM) is a commonplace means of producing objects employed in "real world" products, appropriate design knowledge must be sufficiently integrated within industry. First, materials suited to additive manufacturing methods must be developed to satisfy existing industry standards and specifications, or new standards must be developed. Second, a new class of design representation (CAD) tools will need to be developed. Third, designers and design organizations will need to develop strategies for employing such tools. This thesis describes three DFAM exercises intended to demonstrate the potential for innovative design when using advanced additive materials, tools, and printers. These design exercises included 1) a light-weight composite layup mold developed with topology optimization, 2) a low-pressure fluid duct enhanced with an external lattice structure, and 3) an airline seat tray designed using a non-uniform lattice structure optimized with topology optimization.

  12. Numerical simulation of metallic wire arc additive manufacturing (WAAM)

    NASA Astrophysics Data System (ADS)

    Graf, M.; Pradjadhiana, K. P.; Hälsig, A.; Manurung, Y. H. P.; Awiszus, B.

    2018-05-01

    Additive-manufacturing technologies have been gaining tremendously in popularity for some years in the production of single-part series with complex, close-to-final-contour geometries and the processing of special or hybrid materials. In principle, the processes can be subdivided into wire-based and powder-based processes in accordance with the Association of German Engineers (VDI) Guideline 3405. A further subdivision is made with respect to the smelting technology. In all of the processes, the base material is applied in layers at the points where it is needed in accordance with the final contour. The process that was investigated was wire-based, multi-pass welding by means of gas-metal arc welding. This was accomplished in the present study by determining the material parameters (thermo-mechanical and thermo-physical characteristics) of the welding filler G3Si1 (material number: 1.5125) that were necessary for the numerical simulation and implementing them in a commercial FE program (MSC Marc Mentat). The focus of this paper was on simulation and validation with respect to geometry and microstructural development in the welding passes. The resulting minimal deviation between reality and simulation was a result of the measurement inertia of the thermocouples. In general, however, the FE model can be used to make a very good predetermination of the cooling behaviour, which affects the microstructural development and thus the mechanical properties of the joining zone, as well as the geometric design of the component (distortion, etc.).

  13. Additively manufactured metallic pentamode meta-materials

    NASA Astrophysics Data System (ADS)

    Hedayati, R.; Leeflang, A. M.; Zadpoor, A. A.

    2017-02-01

    Mechanical metamaterials exhibit unusual mechanical properties that originate from their topological design. Pentamode metamaterials are particularly interesting because they could be designed to possess any thermodynamically admissible elasticity tensor. In this study, we additively manufacture the metallic pentamode metamaterials from a biocompatible and mechanically strong titanium alloy (Ti-6Al-4V) using an energy distribution method developed for the powder bed fusion techniques. The mechanical properties of the developed materials were a few orders of magnitude higher than those of the similar topologies fabricated previously from polymers. Moreover, the elastic modulus and yield stress of the presented pentamode metamaterials were decoupled from their relative density, meaning that the metallic meta-biomaterials with independently tailored elastic and mass transport (permeability) properties could be designed for tissue regeneration purposes.

  14. An additive manufacturing-based PCL-alginate-chondrocyte bioprinted scaffold for cartilage tissue engineering.

    PubMed

    Kundu, Joydip; Shim, Jin-Hyung; Jang, Jinah; Kim, Sung-Won; Cho, Dong-Woo

    2015-11-01

    Regenerative medicine is targeted to improve, restore or replace damaged tissues or organs using a combination of cells, materials and growth factors. Both tissue engineering and developmental biology currently deal with the process of tissue self-assembly and extracellular matrix (ECM) deposition. In this investigation, additive manufacturing (AM) with a multihead deposition system (MHDS) was used to fabricate three-dimensional (3D) cell-printed scaffolds using layer-by-layer (LBL) deposition of polycaprolactone (PCL) and chondrocyte cell-encapsulated alginate hydrogel. Appropriate cell dispensing conditions and optimum alginate concentrations for maintaining cell viability were determined. In vitro cell-based biochemical assays were performed to determine glycosaminoglycans (GAGs), DNA and total collagen contents from different PCL-alginate gel constructs. PCL-alginate gels containing transforming growth factor-β (TGFβ) showed higher ECM formation. The 3D cell-printed scaffolds of PCL-alginate gel were implanted in the dorsal subcutaneous spaces of female nude mice. Histochemical [Alcian blue and haematoxylin and eosin (H&E) staining] and immunohistochemical (type II collagen) analyses of the retrieved implants after 4 weeks revealed enhanced cartilage tissue and type II collagen fibril formation in the PCL-alginate gel (+TGFβ) hybrid scaffold. In conclusion, we present an innovative cell-printed scaffold for cartilage regeneration fabricated by an advanced bioprinting technology. Copyright © 2013 John Wiley & Sons, Ltd.

  15. The Current State of Additive Manufacturing in Wind Energy Systems

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mann, Margaret; Palmer, Sierra; Lee, Dominic

    Wind power is an inexhaustible form of energy that is being captured throughout the U.S. to power the engine of our economy. A robust, domestic wind industry promises to increase U.S. industry growth and competitiveness, strengthen U.S. energy security independence, and promote domestic manufacturing nationwide. As of 2016, ~82GW of wind capacity had been installed, and wind power now provides more than 5.5% of the nation’s electricity and supports more than 100,000 domestic jobs, including 500 manufacturing facilities in 43 States. To reach the U.S. Department of Energy’s (DOE’s) 2015 Wind Vision study scenario of wind power serving 35% ofmore » the nation's end-use demand by 2050, significant advances are necessary in all areas of wind technologies and market. An area that can greatly impact the cost and rate of innovation in wind technologies is the use of advanced manufacturing, with one of the most promising areas being additive manufacturing (AM). Considering the tremendous promise offered by advanced manufacturing, it is the purpose of this report to identify the use of AM in the production and operation of wind energy systems. The report has been produced as a collaborative effort for the DOE Wind Energy Technology Office (WETO), between Oak Ridge National Laboratory (ORNL) and the National Renewable Energy Laboratory (NREL).« less

  16. Overview of Materials Qualification Needs for Metal Additive Manufacturing

    NASA Astrophysics Data System (ADS)

    Seifi, Mohsen; Salem, Ayman; Beuth, Jack; Harrysson, Ola; Lewandowski, John J.

    2016-03-01

    This overview highlights some of the key aspects regarding materials qualification needs across the additive manufacturing (AM) spectrum. AM technology has experienced considerable publicity and growth in the past few years with many successful insertions for non-mission-critical applications. However, to meet the full potential that AM has to offer, especially for flight-critical components (e.g., rotating parts, fracture-critical parts, etc.), qualification and certification efforts are necessary. While development of qualification standards will address some of these needs, this overview outlines some of the other key areas that will need to be considered in the qualification path, including various process-, microstructure-, and fracture-modeling activities in addition to integrating these with lifing activities targeting specific components. Ongoing work in the Advanced Manufacturing and Mechanical Reliability Center at Case Western Reserve University is focusing on fracture and fatigue testing to rapidly assess critical mechanical properties of some titanium alloys before and after post-processing, in addition to conducting nondestructive testing/evaluation using micro-computerized tomography at General Electric. Process mapping studies are being conducted at Carnegie Mellon University while large area microstructure characterization and informatics (EBSD and BSE) analyses are being conducted at Materials Resources LLC to enable future integration of these efforts via an Integrated Computational Materials Engineering approach to AM. Possible future pathways for materials qualification are provided.

  17. Diamond field emitter array cathodes and possibilities of employing additive manufacturing for dielectric laser accelerating structures

    NASA Astrophysics Data System (ADS)

    Simakov, Evgenya I.; Andrews, Heather L.; Herman, Matthew J.; Hubbard, Kevin M.; Weis, Eric

    2017-03-01

    Demonstration of a stand-alone practical dielectric laser accelerator (DLA) requires innovation in two major critical components: high-current ultra-low-emittance cathodes and efficient laser accelerator structures. LANL develops two technologies that in our opinion are applicable to the novel DLA architectures: diamond field emitter array (DFEA) cathodes and additive manufacturing of photonic band-gap (PBG) structures. This paper discusses the results of testing of DFEA cathodes in the field-emission regime and the possibilities for their operation in the photoemission regime, and compares their emission characteristics to the specific needs of DLAs. We also describe recent advances in additive manufacturing of dielectric woodpile structures using a Nanoscribe direct laser-writing device capable of maskless lithography and additive manufacturing, and the development of novel infrared dielectric materials compatible with additive manufacturing.

  18. Benchmarking DoD Use of Additive Manufacturing and Quantifying Costs

    DTIC Science & Technology

    2017-03-01

    46 VI. Cost Benefit ...developing a cost model. The US Army Logistics Innovation Agency published a study called “Additive Manufacturing Cost - Benefit Analysis”. This...to over fifteen thousand dollars on GSA Advantage. Desktop printers do not require extensive support equipment. 47    VI. Cost Benefit

  19. Biocompatibility of Advanced Manufactured Titanium Implants-A Review.

    PubMed

    Sidambe, Alfred T

    2014-12-19

    Titanium (Ti) and its alloys may be processed via advanced powder manufacturing routes such as additive layer manufacturing (or 3D printing) or metal injection moulding. This field is receiving increased attention from various manufacturing sectors including the medical devices sector. It is possible that advanced manufacturing techniques could replace the machining or casting of metal alloys in the manufacture of devices because of associated advantages that include design flexibility, reduced processing costs, reduced waste, and the opportunity to more easily manufacture complex or custom-shaped implants. The emerging advanced manufacturing approaches of metal injection moulding and additive layer manufacturing are receiving particular attention from the implant fabrication industry because they could overcome some of the difficulties associated with traditional implant fabrication techniques such as titanium casting. Using advanced manufacturing, it is also possible to produce more complex porous structures with improved mechanical performance, potentially matching the modulus of elasticity of local bone. While the economic and engineering potential of advanced manufacturing for the manufacture of musculo-skeletal implants is therefore clear, the impact on the biocompatibility of the materials has been less investigated. In this review, the capabilities of advanced powder manufacturing routes in producing components that are suitable for biomedical implant applications are assessed with emphasis placed on surface finishes and porous structures. Given that biocompatibility and host bone response are critical determinants of clinical performance, published studies of in vitro and in vivo research have been considered carefully. The review concludes with a future outlook on advanced Ti production for biomedical implants using powder metallurgy.

  20. Biocompatibility of Advanced Manufactured Titanium Implants—A Review

    PubMed Central

    Sidambe, Alfred T.

    2014-01-01

    Titanium (Ti) and its alloys may be processed via advanced powder manufacturing routes such as additive layer manufacturing (or 3D printing) or metal injection moulding. This field is receiving increased attention from various manufacturing sectors including the medical devices sector. It is possible that advanced manufacturing techniques could replace the machining or casting of metal alloys in the manufacture of devices because of associated advantages that include design flexibility, reduced processing costs, reduced waste, and the opportunity to more easily manufacture complex or custom-shaped implants. The emerging advanced manufacturing approaches of metal injection moulding and additive layer manufacturing are receiving particular attention from the implant fabrication industry because they could overcome some of the difficulties associated with traditional implant fabrication techniques such as titanium casting. Using advanced manufacturing, it is also possible to produce more complex porous structures with improved mechanical performance, potentially matching the modulus of elasticity of local bone. While the economic and engineering potential of advanced manufacturing for the manufacture of musculo-skeletal implants is therefore clear, the impact on the biocompatibility of the materials has been less investigated. In this review, the capabilities of advanced powder manufacturing routes in producing components that are suitable for biomedical implant applications are assessed with emphasis placed on surface finishes and porous structures. Given that biocompatibility and host bone response are critical determinants of clinical performance, published studies of in vitro and in vivo research have been considered carefully. The review concludes with a future outlook on advanced Ti production for biomedical implants using powder metallurgy. PMID:28788296

  1. 3D Volume Rendering and 3D Printing (Additive Manufacturing).

    PubMed

    Katkar, Rujuta A; Taft, Robert M; Grant, Gerald T

    2018-07-01

    Three-dimensional (3D) volume-rendered images allow 3D insight into the anatomy, facilitating surgical treatment planning and teaching. 3D printing, additive manufacturing, and rapid prototyping techniques are being used with satisfactory accuracy, mostly for diagnosis and surgical planning, followed by direct manufacture of implantable devices. The major limitation is the time and money spent generating 3D objects. Printer type, material, and build thickness are known to influence the accuracy of printed models. In implant dentistry, the use of 3D-printed surgical guides is strongly recommended to facilitate planning and reduce risk of operative complications. Copyright © 2018 Elsevier Inc. All rights reserved.

  2. Porosity Measurements and Analysis for Metal Additive Manufacturing Process Control.

    PubMed

    Slotwinski, John A; Garboczi, Edward J; Hebenstreit, Keith M

    2014-01-01

    Additive manufacturing techniques can produce complex, high-value metal parts, with potential applications as critical metal components such as those found in aerospace engines and as customized biomedical implants. Material porosity in these parts is undesirable for aerospace parts - since porosity could lead to premature failure - and desirable for some biomedical implants - since surface-breaking pores allows for better integration with biological tissue. Changes in a part's porosity during an additive manufacturing build may also be an indication of an undesired change in the build process. Here, we present efforts to develop an ultrasonic sensor for monitoring changes in the porosity in metal parts during fabrication on a metal powder bed fusion system. The development of well-characterized reference samples, measurements of the porosity of these samples with multiple techniques, and correlation of ultrasonic measurements with the degree of porosity are presented. A proposed sensor design, measurement strategy, and future experimental plans on a metal powder bed fusion system are also presented.

  3. Porosity Measurements and Analysis for Metal Additive Manufacturing Process Control

    PubMed Central

    Slotwinski, John A; Garboczi, Edward J; Hebenstreit, Keith M

    2014-01-01

    Additive manufacturing techniques can produce complex, high-value metal parts, with potential applications as critical metal components such as those found in aerospace engines and as customized biomedical implants. Material porosity in these parts is undesirable for aerospace parts - since porosity could lead to premature failure - and desirable for some biomedical implants - since surface-breaking pores allows for better integration with biological tissue. Changes in a part’s porosity during an additive manufacturing build may also be an indication of an undesired change in the build process. Here, we present efforts to develop an ultrasonic sensor for monitoring changes in the porosity in metal parts during fabrication on a metal powder bed fusion system. The development of well-characterized reference samples, measurements of the porosity of these samples with multiple techniques, and correlation of ultrasonic measurements with the degree of porosity are presented. A proposed sensor design, measurement strategy, and future experimental plans on a metal powder bed fusion system are also presented. PMID:26601041

  4. Additive Manufacturing of Tooling for Refrigeration Cabinet Foaming Processes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Post, Brian K; Nuttall, David; Cukier, Michael

    The primary objective of this project was to leverage the Big Area Additive Manufacturing (BAAM) process and materials into a long term, quick change tooling concept to drastically reduce product lead and development timelines and costs. Current refrigeration foam molds are complicated to manufacture involving casting several aluminum parts in an approximate shape, machining components of the molds and post fitting and shimming of the parts in an articulated fixture. The total process timeline can take over 6 months. The foaming process is slower than required for production, therefore multiple fixtures, 10 to 27, are required per refrigerator model. Moldsmore » are particular to a specific product configuration making mixed model assembly challenging for sequencing, mold changes or auto changeover features. The initial goal was to create a tool leveraging the ORNL materials and additive process to build a tool in 4 to 6 weeks or less. A secondary goal was to create common fixture cores and provide lightweight fixture sections that could be revised in a very short time to increase equipment flexibility reduce lead times, lower the barriers to first production trials, and reduce tooling costs.« less

  5. A study on Aerosol jet printing technology in LED module manufacturing

    NASA Astrophysics Data System (ADS)

    Rudorfer, Andreas; Tscherner, Martin; Palfinger, Christian; Reil, Frank; Hartmann, Paul; Seferis, Ioannis E.; Zych, Eugeniusz; Wenzl, Franz P.

    2016-09-01

    State of the art fabrication of LED modules based on chip-on-board (COB) technology comprises some shortcomings both with respect to the manufacturing process itself but also with regard to potential sources of failures and manufacturing impreciseness. One promising alternative is additive manufacturing, a technology which has gained a lot of attention during the last years due to its materials and cost saving capabilities. Especially direct-write technologies like Aerosol jet printing have demonstrated advantages compared to other technological approaches when printing high precision layers or high precision electronic circuits on substrates which, as an additional advantage, also can be flexible and 3D shaped. Based on test samples and test structures manufactured by Aerosol jet printing technology, in this context we discuss the potentials of additive manufacturing in various aspects of LED module fabrication, ranging from the deposition of the die-attach material, wire bond replacement by printed electrical connects as well as aspects of high-precision phosphor layer deposition for color conversion and white light generation.

  6. Microstructure and Corrosion Resistance of Laser Additively Manufactured 316L Stainless Steel

    NASA Astrophysics Data System (ADS)

    Trelewicz, Jason R.; Halada, Gary P.; Donaldson, Olivia K.; Manogharan, Guha

    2016-03-01

    Additive manufacturing (AM) of metal alloys to produce complex part designs via powder bed fusion methods such as laser melting promises to be a transformative technology for advanced materials processing. However, effective implementation of AM processes requires a clear understanding of the processing-structure-properties-performance relationships in fabricated components. In this study, we report on the formation of micro and nanoscale structures in 316L stainless steel samples printed by laser AM and their implications for general corrosion resistance. A variety of techniques including x-ray diffraction, optical, scanning and transmission electron microscopy, x-ray fluorescence, and energy dispersive x-ray spectroscopy were employed to characterize the microstructure and chemistry of the laser additively manufactured 316L stainless steel, which are compared with wrought 316L coupons via electrochemical polarization. Apparent segregation of Mo has been found to contribute to a loss of passivity and an increased anodic current density. While porosity will also likely impact the environmental performance (e.g., facilitating crevice corrosion) of AM alloys, this work demonstrates the critical influence of microstructure and heterogeneous solute distributions on the corrosion resistance of laser additively manufactured 316L stainless steel.

  7. Carbon Nanotube Chopped Fiber for Enhanced Properties in Additive Manufacturing

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Menchhofer, Paul A.; Johnson, Joseph E.; Lindahl, John M.

    2016-06-06

    Nanocomp Technologies, Inc. is working with Oak Ridge National Laboratory to develop carbon nanotube (CNT) composite materials and evaluate their use in additive manufacturing (3D printing). The first phase demonstrated feasibility and improvements for carbon nanotube (CNT)- acrylonitrile butadiene styrene (ABS) composite filaments use in additive manufacturing, with potential future work centering on further improvements. By focusing the initial phase on standard processing methods (developed mainly for the incorporation of carbon fibers in ABS) and characterization techniques, a basis of knowledge for the incorporation of CNTs in ABS was learned. The ability to understand the various processing variables is criticalmore » to the successful development of these composites. From the degradation effects on ABS (caused by excessive temperatures), to the length of time the ABS is in the melt state, to the order of addition of constituents, and also to the many possible mixing approaches, a workable flow sequence that addresses each processing step is critical to the final material properties. Although this initial phase could not deal with each of these variables in-depth, a future study is recommended that will build on the lessons learned for this effort.« less

  8. Mechanical Properties and Fracture Behaviors of GTA-Additive Manufactured 2219-Al After an Especial Heat Treatment

    NASA Astrophysics Data System (ADS)

    Bai, J. Y.; Fan, C. L.; Lin, S. B.; Yang, C. L.; Dong, B. L.

    2017-04-01

    2219-Al parts were produced by gas tungsten arc-additive manufacturing and sequentially processed by an especial heat treatment. In order to investigate the effects of heat treatment on its mechanical properties, multiple tests were conducted. Hardness tests were carried out on part scale and layer scale along with tensile tests which were performed on welding and building directions. Results show that compared to conventional casting + T6 2219-Al, the current deposit + T6 2219-Al exhibits satisfying properties with regard to strength but unsatisfying results in plasticity. Additionally, anisotropy is significant. Fractures were observed and the cracks' propagating paths in both directional specimens are described. The effects of heat treatment on the cracks' initiation and propagation were also investigated. Ultimately, a revised formula was developed to calculate the strength of the deposit + T6 2219-Al. The aforementioned formula, which takes into consideration the belt-like porosities-distributing feature, can scientifically describe the anisotropic properties in the material.

  9. Geometric Modeling of Cellular Materials for Additive Manufacturing in Biomedical Field: A Review.

    PubMed

    Savio, Gianpaolo; Rosso, Stefano; Meneghello, Roberto; Concheri, Gianmaria

    2018-01-01

    Advances in additive manufacturing technologies facilitate the fabrication of cellular materials that have tailored functional characteristics. The application of solid freeform fabrication techniques is especially exploited in designing scaffolds for tissue engineering. In this review, firstly, a classification of cellular materials from a geometric point of view is proposed; then, the main approaches on geometric modeling of cellular materials are discussed. Finally, an investigation on porous scaffolds fabricated by additive manufacturing technologies is pointed out. Perspectives in geometric modeling of scaffolds for tissue engineering are also proposed.

  10. Additive manufacturing of magnetic shielding and ultra-high vacuum flange for cold atom sensors.

    PubMed

    Vovrosh, Jamie; Voulazeris, Georgios; Petrov, Plamen G; Zou, Ji; Gaber, Youssef; Benn, Laura; Woolger, David; Attallah, Moataz M; Boyer, Vincent; Bongs, Kai; Holynski, Michael

    2018-01-31

    Recent advances in the understanding and control of quantum technologies, such as those based on cold atoms, have resulted in devices with extraordinary metrological performance. To realise this potential outside of a lab environment the size, weight and power consumption need to be reduced. Here we demonstrate the use of laser powder bed fusion, an additive manufacturing technique, as a production technique relevant to the manufacture of quantum sensors. As a demonstration we have constructed two key components using additive manufacturing, namely magnetic shielding and vacuum chambers. The initial prototypes for magnetic shields show shielding factors within a factor of 3 of conventional approaches. The vacuum demonstrator device shows that 3D-printed titanium structures are suitable for use as vacuum chambers, with the test system reaching base pressures of 5 ± 0.5 × 10 -10 mbar. These demonstrations show considerable promise for the use of additive manufacturing for cold atom based quantum technologies, in future enabling improved integrated structures, allowing for the reduction in size, weight and assembly complexity.

  11. Next-generation biomedical implants using additive manufacturing of complex, cellular and functional mesh arrays.

    PubMed

    Murr, L E; Gaytan, S M; Medina, F; Lopez, H; Martinez, E; Machado, B I; Hernandez, D H; Martinez, L; Lopez, M I; Wicker, R B; Bracke, J

    2010-04-28

    In this paper, we examine prospects for the manufacture of patient-specific biomedical implants replacing hard tissues (bone), particularly knee and hip stems and large bone (femoral) intramedullary rods, using additive manufacturing (AM) by electron beam melting (EBM). Of particular interest is the fabrication of complex functional (biocompatible) mesh arrays. Mesh elements or unit cells can be divided into different regions in order to use different cell designs in different areas of the component to produce various or continually varying (functionally graded) mesh densities. Numerous design elements have been used to fabricate prototypes by AM using EBM of Ti-6Al-4V powders, where the densities have been compared with the elastic (Young) moduli determined by resonant frequency and damping analysis. Density optimization at the bone-implant interface can allow for bone ingrowth and cementless implant components. Computerized tomography (CT) scans of metal (aluminium alloy) foam have also allowed for the building of Ti-6Al-4V foams by embedding the digital-layered scans in computer-aided design or software models for EBM. Variations in mesh complexity and especially strut (or truss) dimensions alter the cooling and solidification rate, which alters the alpha-phase (hexagonal close-packed) microstructure by creating mixtures of alpha/alpha' (martensite) observed by optical and electron metallography. Microindentation hardness measurements are characteristic of these microstructures and microstructure mixtures (alpha/alpha') and sizes.

  12. Numerical and Experimental Study of Ti6Al4V Components Manufactured Using Powder Bed Fusion Additive Manufacturing

    NASA Astrophysics Data System (ADS)

    Zielinski, Jonas; Mindt, Hans-Wilfried; Düchting, Jan; Schleifenbaum, Johannes Henrich; Megahed, Mustafa

    2017-12-01

    Powder bed fusion additive manufacturing of titanium alloys is an interesting manufacturing route for many applications requiring high material strength combined with geometric complexity. Managing powder bed fusion challenges, including porosity, surface finish, distortions and residual stresses of as-built material, is the key to bringing the advantages of this process to production main stream. This paper discusses the application of experimental and numerical analysis towards optimizing the manufacturing process of a demonstration component. Powder characterization including assessment of the reusability, assessment of material consolidation and process window optimization is pursued prior to applying the identified optima to study the distortion and residual stresses of the demonstrator. Comparisons of numerical predictions with measurements show good correlations along the complete numerical chain.

  13. Test and Evaluation of Ultrasonic Additive Manufacturing (UAM) for a Large Aircraft Maintenance Shelter (LAMS) Baseplate

    DTIC Science & Technology

    2015-03-26

    TEST AND EVALUATION OF ULTRASONIC ADDITIVE MANUFACTURING (UAM) FOR A LARGE AREA MAINTENANCE...States Government. AFIT-ENV-MS-15-M-158 TEST AND EVALUATION OF ULTRASONIC ADDITIVE MANUFACTURING FOR A LARGE AREA MAINTENANCE SHELTER...Civil Engineer (CE) operations. This research replicates a Large Area Maintenance Shelter (LAMS) baseplate design for ultrasonic additive

  14. Additive Manufacturing of Aerospace Alloys for Aircraft Structures

    DTIC Science & Technology

    2006-05-01

    power and traverse speed on microstructure, porosity , and build height in laser-deposited Ti- 6Al - 4V ”, Scripta Mater., Vol. 43, pp. 299-305, 2000. [10...laser additive manufacturing) process to produce Ti- 6Al - 4V structures. Many similar processes are under development elsewhere, including electron-beam...wattage CO2 laser and a powder feed system to deposit wide, thick beads (~ 0.5” x 0.15”) of Ti- 6Al - 4V onto a substrate. The primary LAMSM deposition

  15. Embracing additive manufacture: implications for foot and ankle orthosis design

    PubMed Central

    2012-01-01

    Background The design of foot and ankle orthoses is currently limited by the methods used to fabricate the devices, particularly in terms of geometric freedom and potential to include innovative new features. Additive manufacturing (AM) technologies, where objects are constructed via a series of sub-millimetre layers of a substrate material, may present the opportunity to overcome these limitations and allow novel devices to be produced that are highly personalised for the individual, both in terms of fit and functionality. Two novel devices, a foot orthosis (FO) designed to include adjustable elements to relieve pressure at the metatarsal heads, and an ankle foot orthosis (AFO) designed to have adjustable stiffness levels in the sagittal plane, were developed and fabricated using AM. The devices were then tested on a healthy participant to determine if the intended biomechanical modes of action were achieved. Results The adjustable, pressure relieving FO was found to be able to significantly reduce pressure under the targeted metatarsal heads. The AFO was shown to have distinct effects on ankle kinematics which could be varied by adjusting the stiffness level of the device. Conclusions The results presented here demonstrate the potential design freedom made available by AM, and suggest that it may allow novel personalised orthotic devices to be produced which are beyond the current state of the art. PMID:22642941

  16. 3D model of filler melting with micro-beam plasma arc based on additive manufacturing technology

    NASA Astrophysics Data System (ADS)

    Chen, Weilin; Yang, Tao; Yang, Ruixin

    2017-07-01

    Additive manufacturing technology is a systematic process based on discrete-accumulation principle, which is derived by the dimension of parts. Aiming at the dimension mathematical model and slicing problems in additive manufacturing process, the constitutive relations between micro-beam plasma welding parameters and the dimension of part were investigated. The slicing algorithm and slicing were also studied based on the dimension characteristics. By using the direct slicing algorithm according to the geometric characteristics of model, a hollow thin-wall spherical part was fabricated by 3D additive manufacturing technology using micro-beam plasma.

  17. Additive Manufacturing: An Enabling Technology for the MoonBEAM 6U CubeSat Missions

    NASA Technical Reports Server (NTRS)

    Hopkins, R. C.; Hickman, R. R.; Cavender, D. P.; Dominquez, A.; Schnell, A. R.; Baysinger, M.; Capizzo, P.; Garcia, J.; Fabisinski, L. L.

    2017-01-01

    The Advanced Concepts Office at the NASA Marshall Space Flight Center completed a mission concept study for the Moon Burst Energetics All-sky Monitor (MoonBEAM). The goal of the concept study was to show the enabling aspects that additive manufacturing can provide to CubeSats. In addition to using the additively manufactured tanks as part of the spacecraft structure, the main propulsion system uses a green propellant, which is denser than hydrazine. Momentum unloading is achieved with electric microthrusters, eliminating much of the propellant plumbing. The science mission, requirements, and spacecraft design are described.

  18. Geometric Modeling of Cellular Materials for Additive Manufacturing in Biomedical Field: A Review

    PubMed Central

    Rosso, Stefano; Meneghello, Roberto; Concheri, Gianmaria

    2018-01-01

    Advances in additive manufacturing technologies facilitate the fabrication of cellular materials that have tailored functional characteristics. The application of solid freeform fabrication techniques is especially exploited in designing scaffolds for tissue engineering. In this review, firstly, a classification of cellular materials from a geometric point of view is proposed; then, the main approaches on geometric modeling of cellular materials are discussed. Finally, an investigation on porous scaffolds fabricated by additive manufacturing technologies is pointed out. Perspectives in geometric modeling of scaffolds for tissue engineering are also proposed. PMID:29487626

  19. Additive Manufacture of Plasma Diagnostic Components Final Report Phase II

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Woodruff, Simon; Romero-Talamas, Carlos; You, Setthivoine

    There is now a well-established set of plasma diagnostics (see e.g. [3]), but these remain some of the mostexpensive assemblies in fusion systems since for every system they have to be custom built, and time fordiagnostic development can pace the project. Additive manufacturing (AM) has the potential to decreaseproduction cost and significantly lower design time of fusion diagnostic subsystems, which would realizesignificant cost reduction for standard diagnostics. In some cases, these basic components can be additivelymanufactured for less than 1/100th costs of conventional manufacturing.In our DOE Phase II SBIR, we examined the impact that AM can have on plasma diagnosticmore » cost bytaking 15 separate diagnostics through an engineering design using Conventional Manufacturing (CM) tech-niques, then optimizing the design to exploit the benefits of AM. The impact of AM techniques on cost isfound to be in several areas. First, the cost of materials falls because AM parts can be manufactured withlittle to no waste, and engineered to use less material than CM. Next, the cost of fabrication falls for AMparts relative to CM since the fabrication time can be computed exactly, and often no post-processing isrequired for the part to be functional. We find that AM techniques are well suited for plasma diagnosticssince typical diagnostic complexity comes at no additional cost. Cooling channels, for example, can be builtin to plasma-facing components at no extra cost. Fabrication costs associated with assembly are lower forAM parts because many components can be combined and printed as monoliths, thereby mitigating the needfor alignment or calibration. Finally, the cost of engineering is impacted by exploiting AM design tools thatallow standard components to be customized through web-interfaces. Furthermore, we find that conceptdesign costs can be impacted by scripting interfaces for online engineering design tools.« less

  20. Additive manufacturing capabilities applied to inertial confinement confusion at Los Alamos National Laboratory

    DOE PAGES

    Cardenas, Tana; Schmidt, Derek William; Peterson, Dominic S.

    2016-08-01

    We describe the use at Los Alamos National Laboratory of additive manufacturing (AM) for a variety of jigs and coating, assembly, and radiography fixtures. Additive manufacturing has also been used to produce shipping containers of complex design that would be too costly to have fabricated using traditional techniques. The current goal for AM use in target fabrication is to increase target accuracy and rigidity. This has been realized by implementing AM into target stalk fabrication, allowing increased complexity to address target strength and the addition of features for alignment at facilities. As a result, we will describe the fabrication ofmore » these components and our plans to utilize AM in the future.« less

  1. Laser-Assisted Wire Additive Manufacturing System for the Deep Space Gateway

    NASA Astrophysics Data System (ADS)

    Foster, B. D.; Matthews, B.

    2018-02-01

    Investigation on the Deep Space Gateway will involve experiments/operations inside pressurized modules. Support for those experiments may necessitate a means to fabricate and repair required articles. This capability can be provided through an additive manufacturing (AM) system.

  2. Additive Manufacturing of Metallic and Ceramic Components by the Material Extrusion of Highly-Filled Polymers: A Review and Future Perspectives

    PubMed Central

    Cano, Santiago

    2018-01-01

    Additive manufacturing (AM) is the fabrication of real three-dimensional objects from metals, ceramics, or plastics by adding material, usually as layers. There are several variants of AM; among them material extrusion (ME) is one of the most versatile and widely used. In MEAM, molten or viscous materials are pushed through an orifice and are selectively deposited as strands to form stacked layers and subsequently a three-dimensional object. The commonly used materials for MEAM are thermoplastic polymers and particulate composites; however, recently innovative formulations of highly-filled polymers (HP) with metals or ceramics have also been made available. MEAM with HP is an indirect process, which uses sacrificial polymeric binders to shape metallic and ceramic components. After removing the binder, the powder particles are fused together in a conventional sintering step. In this review the different types of MEAM techniques and relevant industrial approaches for the fabrication of metallic and ceramic components are described. The composition of certain HP binder systems and powders are presented; the methods of compounding and filament making HP are explained; the stages of shaping, debinding, and sintering are discussed; and finally a comparison of the parts produced via MEAM-HP with those produced via other manufacturing techniques is presented. PMID:29783705

  3. Additive Manufacturing of Metallic and Ceramic Components by the Material Extrusion of Highly-Filled Polymers: A Review and Future Perspectives.

    PubMed

    Gonzalez-Gutierrez, Joamin; Cano, Santiago; Schuschnigg, Stephan; Kukla, Christian; Sapkota, Janak; Holzer, Clemens

    2018-05-18

    Additive manufacturing (AM) is the fabrication of real three-dimensional objects from metals, ceramics, or plastics by adding material, usually as layers. There are several variants of AM; among them material extrusion (ME) is one of the most versatile and widely used. In MEAM, molten or viscous materials are pushed through an orifice and are selectively deposited as strands to form stacked layers and subsequently a three-dimensional object. The commonly used materials for MEAM are thermoplastic polymers and particulate composites; however, recently innovative formulations of highly-filled polymers (HP) with metals or ceramics have also been made available. MEAM with HP is an indirect process, which uses sacrificial polymeric binders to shape metallic and ceramic components. After removing the binder, the powder particles are fused together in a conventional sintering step. In this review the different types of MEAM techniques and relevant industrial approaches for the fabrication of metallic and ceramic components are described. The composition of certain HP binder systems and powders are presented; the methods of compounding and filament making HP are explained; the stages of shaping, debinding, and sintering are discussed; and finally a comparison of the parts produced via MEAM-HP with those produced via other manufacturing techniques is presented.

  4. Additively Manufactured IN718 Components with Wirelessly Powered and Interrogated Embedded Sensing

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Attridge, Paul; Bajekal, Sanjay; Klecka, Michael

    A methodology is described for embedding commercial-off-the-shelf sensors together with wireless communication and power circuit elements using direct laser metal sintered additively manufactured components. Physics based models of the additive manufacturing processes and sensor/wireless level performance models guided the design and embedment processes. A combination of cold spray deposition and laser engineered net shaping was used to fashion the transmitter/receiving elements and embed the sensors, thereby providing environmental protection and component robustness/survivability for harsh conditions. By design, this complement of analog and digital sensors were wirelessly powered and interrogated using a health and utilization monitoring system; enabling real-time, in situmore » prognostics and diagnostics.« less

  5. Next Generation Orthopaedic Implants by Additive Manufacturing Using Electron Beam Melting

    PubMed Central

    Murr, Lawrence E.; Gaytan, Sara M.; Martinez, Edwin; Medina, Frank; Wicker, Ryan B.

    2012-01-01

    This paper presents some examples of knee and hip implant components containing porous structures and fabricated in monolithic forms utilizing electron beam melting (EBM). In addition, utilizing stiffness or relative stiffness versus relative density design plots for open-cellular structures (mesh and foam components) of Ti-6Al-4V and Co-29Cr-6Mo alloy fabricated by EBM, it is demonstrated that stiffness-compatible implants can be fabricated for optimal stress shielding for bone regimes as well as bone cell ingrowth. Implications for the fabrication of patient-specific, monolithic, multifunctional orthopaedic implants using EBM are described along with microstructures and mechanical properties characteristic of both Ti-6Al-4V and Co-29Cr-6Mo alloy prototypes, including both solid and open-cellular prototypes manufactured by additive manufacturing (AM) using EBM. PMID:22956957

  6. Fabrication of Thermoelectric Devices Using Additive-Subtractive Manufacturing Techniques: Application to Waste-Heat Energy Harvesting

    NASA Astrophysics Data System (ADS)

    Tewolde, Mahder

    Thermoelectric generators (TEGs) are solid-state devices that convert heat directly into electricity. They are well suited for waste-heat energy harvesting applications as opposed to primary energy generation. Commercially available thermoelectric modules are flat, inflexible and have limited sizes available. State-of-art manufacturing of TEG devices relies on assembling prefabricated parts with soldering, epoxy bonding, and mechanical clamping. Furthermore, efforts to incorporate them onto curved surfaces such as exhaust pipes, pump housings, steam lines, mixing containers, reaction chambers, etc. require custom-built heat exchangers. This is costly and labor-intensive, in addition to presenting challenges in terms of space, thermal coupling, added weight and long-term reliability. Additive manufacturing technologies are beginning to address many of these issues by reducing part count in complex designs and the elimination of sub-assembly requirements. This work investigates the feasibility of utilizing such novel manufacturing routes for improving the manufacturing process of thermoelectric devices. Much of the research in thermoelectricity is primarily focused on improving thermoelectric material properties by developing of novel materials or finding ways to improve existing ones. Secondary to material development is improving the manufacturing process of TEGs to provide significant cost benefits. To improve the device fabrication process, this work explores additive manufacturing technologies to provide an integrated and scalable approach for TE device manufacturing directly onto engineering component surfaces. Additive manufacturing techniques like thermal spray and ink-dispenser printing are developed with the aim of improving the manufacturing process of TEGs. Subtractive manufacturing techniques like laser micromachining are also studied in detail. This includes the laser processing parameters for cutting the thermal spray materials efficiently by

  7. Design, Development and Hotfire Testing of Monolithic Copper and Bimetallic Additively Manufactured Combustion Chambers

    NASA Technical Reports Server (NTRS)

    Gradl, Paul; Barnett, Greg; Brandsmeier, Will; Greene, Sandy Elam; Protz, Chris

    2016-01-01

    NASA and industry partners are working towards fabrication process development to reduce costs and schedules associated with manufacturing liquid rocket engine components with the goal of reducing overall mission costs. One such technique being evaluated is powder-bed fusion or selective laser melting (SLM) otherwise commonly referred to as additive manufacturing. The NASA Low Cost Upper Stage Propulsion (LCUSP) program was designed to develop processes and material characterization for the GRCop-84 copper-alloy commensurate with powder bed additive manufacturing, evaluate bimetallic deposition and complete testing of a full scale combustion chamber. As part of this development, the process has been transferred to industry partners to enable a long-term supply chain of monolithic copper combustion chambers. As a direct spin off of this program, NASA is working with industry partners to further develop the printing process for the GRCop-84 material in addition to the C-18150 (CuCrZr) material. To advance the process further and allow for optimization with multiple materials, NASA is also investigating the feasibility of bimetallic additively manufactured chambers. A 1.2k sized thrust-chamber was designed and developed to compare the printing process of the GRCop-84 and C-18150 SLM materials. A series of similar MCC liners also completed development with an Inconel 625 jacket bonded to the GRcop-84 liner evaluating direct metal deposition (DMD) laser and arc-based techniques. This paper describes the design, development, manufacturing and testing of these combustion chambers and associated lessons learned throughout the design and development process.

  8. Standardization of rate of sugar addition for the manufacture of Thabdi.

    PubMed

    Hirpara, Krupa B; Patel, H G; Prajapati, J P

    2015-02-01

    Traditional Indian Dairy Products are manufactured in India using an age old practice which varies from place to place. For manufacture of these products industrially, a standard formulation is required. Thabdi, a region specific, very popular heat desiccated milk product is one of such products which has not been studied scientifically. Sugar plays an important role in physico-chemical, sensory, textural characteristics and also the shelf life of any milk sweet. Hence for process standardization of Thabdi manufacture, different levels of sugar i.e. 4, 6, 8 and 10 (percent of milk) were studied so that an optimum level yielding best organoleptic characteristics in final product can be selected. The product was made from milk standardized to 0.66 Fat:SNF level and added with ghee @ 1.2 % of milk at the time of colour and texture development stage as selected from the earlier phase of study. Based on the results obtained, a level of 8 % sugar addition on the milk basis at the time of manufacture has been selected to have full taste and sensory attributes.

  9. Mechanical strength of welding zones produced by material extrusion additive manufacturing.

    PubMed

    Davis, Chelsea S; Hillgartner, Kaitlyn E; Han, Seung Hoon; Seppala, Jonathan E

    2017-08-01

    As more manufacturing processes and research institutions adopt customized manufacturing as a key element in their design strategies and finished products, the resulting mechanical properties of parts produced through additive manufacturing (AM) must be characterized and understood. In material extrusion (MatEx), the most recently extruded polymer filament must bond to the previously extruded filament via polymer diffusion to form a "weld". The strength of the weld limits the performance of the manufactured part and is controlled through processing conditions. Under-standing the role of processing conditions, specifically extruder velocity and extruder temperature, on the overall strength of the weld will allow optimization of MatEx-AM parts. Here, the fracture toughness of a single weld is determined through a facile "trouser tear" Mode III fracture experiment. The actual weld thickness is observed directly by optical microscopy characterization of cross sections of MatEx-AM samples. Representative data of weld strength as a function of printing parameters on a commercial 3D printer demonstrates the robustness of the method.

  10. Additive manufacturing of scaffolds with dexamethasone controlled release for enhanced bone regeneration.

    PubMed

    Costa, Pedro F; Puga, Ana M; Díaz-Gomez, Luis; Concheiro, Angel; Busch, Dirk H; Alvarez-Lorenzo, Carmen

    2015-12-30

    The adoption of additive manufacturing in tissue engineering and regenerative medicine (TERM) strategies greatly relies on the development of novel 3D printable materials with advanced properties. In this work we have developed a material for bone TERM applications with tunable bioerosion rate and dexamethasone release profile which can be further employed in fused deposition modelling (the most common and accessible 3D printing technology in the market). The developed material consisted of a blend of poly-ϵ-caprolactone (PCL) and poloxamine (Tetronic®) and was processed into a ready-to-use filament form by means of a simplified melt-based methodology, therefore eliminating the utilization of solvents. 3D scaffolds composed of various blend formulations were additively manufactured and analyzed revealing blend ratio-specific degradation rates and dexamethasone release profiles. Furthermore, in vitro culture studies revealed a similar blend ratio-specific trend concerning the osteoinductive activity of the fabricated scaffolds when these were seeded and cultured with human mesenchymal stem cells. The developed material enables to specifically address different regenerative requirements found in various tissue defects. The versatility of such strategy is further increased by the ability of additive manufacturing to accurately fabricate implants matching any given defect geometry. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. Revival of pure titanium for dynamically loaded porous implants using additive manufacturing.

    PubMed

    Wauthle, Ruben; Ahmadi, Seyed Mohammad; Amin Yavari, Saber; Mulier, Michiel; Zadpoor, Amir Abbas; Weinans, Harrie; Van Humbeeck, Jan; Kruth, Jean-Pierre; Schrooten, Jan

    2015-09-01

    Additive manufacturing techniques are getting more and more established as reliable methods for producing porous metal implants thanks to the almost full geometrical and mechanical control of the designed porous biomaterial. Today, Ti6Al4V ELI is still the most widely used material for porous implants, and none or little interest goes to pure titanium for use in orthopedic or load-bearing implants. Given the special mechanical behavior of cellular structures and the material properties inherent to the additive manufacturing of metals, the aim of this study is to investigate the properties of selective laser melted pure unalloyed titanium porous structures. Therefore, the static and dynamic compressive properties of pure titanium structures are determined and compared to previously reported results for identical structures made from Ti6Al4V ELI and tantalum. The results show that porous Ti6Al4V ELI still remains the strongest material for statically loaded applications, whereas pure titanium has a mechanical behavior similar to tantalum and is the material of choice for cyclically loaded porous implants. These findings are considered to be important for future implant developments since it announces a potential revival of the use of pure titanium for additively manufactured porous implants. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Metal vapor micro-jet controls material redistribution in laser powder bed fusion additive manufacturing.

    PubMed

    Ly, Sonny; Rubenchik, Alexander M; Khairallah, Saad A; Guss, Gabe; Matthews, Manyalibo J

    2017-06-22

    The results of detailed experiments and finite element modeling of metal micro-droplet motion associated with metal additive manufacturing (AM) processes are presented. Ultra high speed imaging of melt pool dynamics reveals that the dominant mechanism leading to micro-droplet ejection in a laser powder bed fusion AM is not from laser induced recoil pressure as is widely believed and found in laser welding processes, but rather from vapor driven entrainment of micro-particles by an ambient gas flow. The physics of droplet ejection under strong evaporative flow is described using simulations of the laser powder bed interactions to elucidate the experimental results. Hydrodynamic drag analysis is used to augment the single phase flow model and explain the entrainment phenomenon for 316 L stainless steel and Ti-6Al-4V powder layers. The relevance of vapor driven entrainment of metal micro-particles to similar fluid dynamic studies in other fields of science will be discussed.

  13. Metal vapor micro-jet controls material redistribution in laser powder bed fusion additive manufacturing

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ly, Sonny; Rubenchik, Alexander M.; Khairallah, Saad A.

    The results of detailed experiments and finite element modeling of metal micro-droplet motion associated with metal additive manufacturing (AM) processes are presented. Ultra high speed imaging of melt pool dynamics reveals that the dominant mechanism leading to micro-droplet ejection in a laser powder bed fusion AM is not from laser induced recoil pressure as is widely believed and found in laser welding processes, but rather from vapor driven entrainment of micro-particles by an ambient gas flow. The physics of droplet ejection under strong evaporative flow is described using simulations of the laser powder bed interactions to elucidate the experimental results.more » Hydrodynamic drag analysis is used to augment the single phase flow model and explain the entrainment phenomenon for 316 L stainless steel and Ti-6Al-4V powder layers. The relevance of vapor driven entrainment of metal micro-particles to similar fluid dynamic studies in other fields of science will be discussed.« less

  14. Metal vapor micro-jet controls material redistribution in laser powder bed fusion additive manufacturing

    DOE PAGES

    Ly, Sonny; Rubenchik, Alexander M.; Khairallah, Saad A.; ...

    2017-06-22

    The results of detailed experiments and finite element modeling of metal micro-droplet motion associated with metal additive manufacturing (AM) processes are presented. Ultra high speed imaging of melt pool dynamics reveals that the dominant mechanism leading to micro-droplet ejection in a laser powder bed fusion AM is not from laser induced recoil pressure as is widely believed and found in laser welding processes, but rather from vapor driven entrainment of micro-particles by an ambient gas flow. The physics of droplet ejection under strong evaporative flow is described using simulations of the laser powder bed interactions to elucidate the experimental results.more » Hydrodynamic drag analysis is used to augment the single phase flow model and explain the entrainment phenomenon for 316 L stainless steel and Ti-6Al-4V powder layers. The relevance of vapor driven entrainment of metal micro-particles to similar fluid dynamic studies in other fields of science will be discussed.« less

  15. Using Additive Manufacturing to Print a CubeSat Propulsion System

    NASA Technical Reports Server (NTRS)

    Marshall, William M.; Zemba, Michael; Shemelya, Corey; Wicker, Ryan; Espalin, David; MacDonald, Eric; Keif, Craig; Kwas, Andrew

    2015-01-01

    Small satellites, such as CubeSats, are increasingly being called upon to perform missions traditionally ascribed to larger satellite systems. However, the market of components and hardware for small satellites, particularly CubeSats, still falls short of providing the necessary capabilities required by ever increasing mission demands. One way to overcome this shortfall is to develop the ability to customize every build. By utilizing fabrication methods such as additive manufacturing, mission specific capabilities can be built into a system, or into the structure, that commercial off-the-shelf components may not be able to provide. A partnership between the University of Texas at El Paso, COSMIAC at the University of New Mexico, Northrop Grumman, and the NASA Glenn Research Center is looking into using additive manufacturing techniques to build a complete CubeSat, under the Small Spacecraft Technology Program. The W. M. Keck Center at the University of Texas at El Paso has previously demonstrated the ability to embed electronics and wires into the addtively manufactured structures. Using this technique, features such as antennas and propulsion systems can be included into the CubeSat structural body. Of interest to this paper, the team is investigating the ability to take a commercial micro pulsed plasma thruster and embed it into the printing process. Tests demonstrating the dielectric strength of the printed material and proof-of-concept demonstration of the printed thruster will be shown.

  16. Dropwise additive manufacturing of pharmaceutical products for melt-based dosage forms.

    PubMed

    Içten, Elçin; Giridhar, Arun; Taylor, Lynne S; Nagy, Zoltan K; Reklaitis, Gintaras V

    2015-05-01

    The US Food and Drug Administration introduced the quality by design approach and process analytical technology guidance to encourage innovation and efficiency in pharmaceutical development, manufacturing, and quality assurance. As part of this renewed emphasis on the improvement of manufacturing, the pharmaceutical industry has begun to develop more efficient production processes with more intensive use of online measurement and sensing, real-time quality control, and process control tools. Here, we present dropwise additive manufacturing of pharmaceutical products (DAMPP) as an alternative to conventional pharmaceutical manufacturing methods. This mini-manufacturing process for the production of pharmaceuticals utilizes drop on demand printing technology for automated and controlled deposition of melt-based formulations onto edible substrates. The advantages of drop-on-demand technology, including reproducible production of small droplets, adjustable drop sizing, high placement accuracy, and flexible use of different formulations, enable production of individualized dosing even for low-dose and high-potency drugs. In this work, DAMPP is used to produce solid oral dosage forms from hot melts of an active pharmaceutical ingredient and a polymer. The dosage forms are analyzed to show the reproducibility of dosing and the dissolution behavior of different formulations. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association.

  17. Dropwise additive manufacturing of pharmaceutical products for solvent-based dosage forms.

    PubMed

    Hirshfield, Laura; Giridhar, Arun; Taylor, Lynne S; Harris, Michael T; Reklaitis, Gintaras V

    2014-02-01

    In recent years, the US Food and Drug Administration has encouraged pharmaceutical companies to develop more innovative and efficient manufacturing methods with improved online monitoring and control. Mini-manufacturing of medicine is one such method enabling the creation of individualized product forms for each patient. This work presents dropwise additive manufacturing of pharmaceutical products (DAMPP), an automated, controlled mini-manufacturing method that deposits active pharmaceutical ingredients (APIs) directly onto edible substrates using drop-on-demand (DoD) inkjet printing technology. The use of DoD technology allows for precise control over the material properties, drug solid state form, drop size, and drop dynamics and can be beneficial in the creation of high-potency drug forms, combination drugs with multiple APIs or individualized medicine products tailored to a specific patient. In this work, DAMPP was used to create dosage forms from solvent-based formulations consisting of API, polymer, and solvent carrier. The forms were then analyzed to determine the reproducibility of creating an on-target dosage form, the morphology of the API of the final form and the dissolution behavior of the drug over time. DAMPP is found to be a viable alternative to traditional mass-manufacturing methods for solvent-based oral dosage forms. © 2013 Wiley Periodicals, Inc. and the American Pharmacists Association.

  18. Additive Manufacturing of Catalyst Substrates for Steam-Methane Reforming

    NASA Astrophysics Data System (ADS)

    Kramer, Michelle; McKelvie, Millie; Watson, Matthew

    2018-01-01

    Steam-methane reforming is a highly endothermic reaction, which is carried out at temperatures up to 1100 °C and pressures up to 3000 kPa, typically with a Ni-based catalyst distributed over a substrate of discrete alumina pellets or beads. Standard pellet geometries (spheres, hollow cylinders) limit the degree of mass transfer between gaseous reactants and catalyst. Further, heat is supplied to the exterior of the reactor wall, and heat transfer is limited due to the nature of point contacts between the reactor wall and the substrate pellets. This limits the degree to which the process can be intensified, as well as limiting the diameter of the reactor wall. Additive manufacturing now gives us the capability to design structures with tailored heat and mass transfer properties, not only within the packed bed of the reactor, but also at the interface between the reactor wall and the packed bed. In this work, the use of additive manufacturing to produce monolithic-structured catalyst substrate models, made from acrylonitrile-butadiene-styrene, with enhanced conductive heat transfer is described. By integrating the reactor wall into the catalyst substrate structure, the effective thermal conductivity increased by 34% from 0.122 to 0.164 W/(m K).

  19. Characterization of Thermoplastic Polyurethane (TPU) and Ag Carbon Black TPU Nanocomposite for Potential Application in Additive Manufacturing (Postprint)

    DTIC Science & Technology

    2016-12-29

    APPLICATION IN ADDITIVE MANUFACTURING (POSTPRINT) Steven T. Patton, Chenggang Chen, Jianjun Hu, and Lawrence Grazulis University of Dayton Research...CARBON BLACK TPU NANOCOMPOSITE FOR POTENTIAL APPLICATION IN ADDITIVE MANUFACTURING (POSTPRINT) 5a. CONTRACT NUMBER FA8650-11-D-5401-0008 5b...and polymer nanocomposites (PNCs) are of interest for additive manufacturing (AM) and flexible electronics. Development/optimization of inks for AM

  20. Fabricating specialised orthopaedic implants using additive manufacturing

    NASA Astrophysics Data System (ADS)

    Unwin, Paul

    2014-03-01

    It has been hypothesised that AM is ideal for patient specific orthopaedic implants such as those used in bone cancer treatment, that can rapidly build structures such as lattices for bone and tissues to in-grow, that would be impossible using current conventional subtractive manufacturing techniques. The aim of this study was to describe the adoption of AM (direct metal laser sintering and electron beam melting) into the design manufacturing and post-manufacturing processes and the early clinical use. Prior to the clinical use of AM implants, extensive metallurgical and mechanical testing of both laser and electron beam fabrications were undertaken. Concurrently, post-manufacturing processes evaluated included hipping, cleaning and coating treatments. The first clinical application of a titanium alloy mega-implant was undertaken in November 2010. A 3D model of the pelvic wing implant was designed from CT scans. Novel key features included extensive lattice structures at the bone interfaces and integral flanges to fix the implant to the bone. The pelvic device was implanted with the aid of navigation and to date the patient remains active. A further 18 patient specific mega-implants have now been implanted. The early use of this advanced manufacturing route for patient specific implants has been very encouraging enabling the engineer to produce more advanced and anatomical conforming implants. However, there are a new set of design, manufacturing and regulatory challenges that require addressing to permit this technique to be used more widely. This technology is changing the design and manufacturing paradigm for the fabrication of specialised orthopaedic implants.

  1. Simulation of metal additive manufacturing microstructures using kinetic Monte Carlo

    DOE PAGES

    Rodgers, Theron M.; Madison, Jonathan D.; Tikare, Veena

    2017-04-19

    Additive manufacturing (AM) is of tremendous interest given its ability to realize complex, non-traditional geometries in engineered structural materials. But, microstructures generated from AM processes can be equally, if not more, complex than their conventionally processed counterparts. While some microstructural features observed in AM may also occur in more traditional solidification processes, the introduction of spatially and temporally mobile heat sources can result in significant microstructural heterogeneity. While grain size and shape in metal AM structures are understood to be highly dependent on both local and global temperature profiles, the exact form of this relation is not well understood. Wemore » implement an idealized molten zone and temperature-dependent grain boundary mobility in a kinetic Monte Carlo model to predict three-dimensional grain structure in additively manufactured metals. In order to demonstrate the flexibility of the model, synthetic microstructures are generated under conditions mimicking relatively diverse experimental results present in the literature. Simulated microstructures are then qualitatively and quantitatively compared to their experimental complements and are shown to be in good agreement.« less

  2. Microstructure of rapidly solidified Nb-based pre-alloyed powders for additive manufacturing

    NASA Astrophysics Data System (ADS)

    Guo, Yueling; Jia, Lina; Kong, Bin; Zhang, Shengnan; Zhang, Fengxiang; Zhang, Hu

    2017-07-01

    For powder-based additive manufacturing, sphere-shaped Nb-37Ti-13Cr-2Al-1Si pre-alloyed powders were prepared by plasma rotating electrode processing (PREP). The microstructure, surface oxidation and microhardness of the pre-alloyed powders were systematically investigated. Results showed that the main phases were Nb solid solution (Nbss) and Cr2Nb. The Cr2Nb phases were further determined using transmission electron microscopy (TEM). Fine dendrite structures were observed in the as-fabricated pre-alloyed powders, which transformed to large grains after heat treatment (HT) at 1450 °C for 3 h. With the increase of powder size, the secondary dendrite arm spacing (SDAS) increased and the microhardness (HV) decreased. A clean powder surface free of oxide particles was obtained by PREP and an oxide layer with 9.39 nm in thickness was generated on the powder surface. Compared with Cr- and Nb-oxides, more Ti-oxides were formed on outmost powder surface with a higher content of Ti (up to 47.86 at.%). The differences upon the microstructure and microhardness of the pre-alloyed powders with different sizes were discussed.

  3. Rationalization of anisotropic mechanical properties of Al-6061 fabricated using ultrasonic additive manufacturing

    DOE PAGES

    Sridharan, Niyanth; Gussev, Maxim; Seibert, Rachel; ...

    2016-09-01

    Ultrasonic additive manufacturing (UAM) is a solid-state process, which uses ultrasonic vibrations at 20 kHz along with mechanized tape layering and intermittent milling operation, to build fully functional three-dimensional parts. In the literature, UAM builds made with low power (1.5 kW) exhibited poor tensile properties in Z-direction, i.e., normal to the interfaces. This reduction in properties is often attributed to the lack of bonding at faying interfaces. The generality of this conclusion is evaluated further in 6061 aluminum alloy builds made with very high power UAM (9 kW). Tensile deformation behavior along X and Z directions were evaluated with small-scalemore » in-situ mechanical testing equipped with high-resolution digital image correlation, as well as, multi-scale characterization of builds. Interestingly, even with complete metallurgical bonding across the interfaces without any discernable voids, poor Z-direction properties were observed. This reduction is correlated to coalescence of pre-existing shear bands at interfaces into micro voids, leading to strain localization and spontaneous failure on tensile loading.« less

  4. Developing Gradient Metal Alloys through Radial Deposition Additive Manufacturing

    PubMed Central

    Hofmann, Douglas C.; Roberts, Scott; Otis, Richard; Kolodziejska, Joanna; Dillon, R. Peter; Suh, Jong-ook; Shapiro, Andrew A.; Liu, Zi-Kui; Borgonia, John-Paul

    2014-01-01

    Interest in additive manufacturing (AM) has dramatically expanded in the last several years, owing to the paradigm shift that the process provides over conventional manufacturing. Although the vast majority of recent work in AM has focused on three-dimensional printing in polymers, AM techniques for fabricating metal alloys have been available for more than a decade. Here, laser deposition (LD) is used to fabricate multifunctional metal alloys that have a strategically graded composition to alter their mechanical and physical properties. Using the technique in combination with rotational deposition enables fabrication of compositional gradients radially from the center of a sample. A roadmap for developing gradient alloys is presented that uses multi-component phase diagrams as maps for composition selection so as to avoid unwanted phases. Practical applications for the new technology are demonstrated in low-coefficient of thermal expansion radially graded metal inserts for carbon-fiber spacecraft panels. PMID:24942329

  5. Additive Manufacturing of Multifunctional Components Using High Density Carbon Nanotube Yarn Filaments

    NASA Technical Reports Server (NTRS)

    Gardner, John M.; Sauti, Godfrey; Kim, Jae-Woo; Cano, Roberto J.; Wincheski, Russell A.; Stelter, Christopher J.; Grimsley, Brian W.; Working, Dennis C.; Siochi, Emilie J.

    2016-01-01

    Additive manufacturing allows for design freedom and part complexity not currently attainable using traditional manufacturing technologies. Fused Filament Fabrication (FFF), for example, can yield novel component geometries and functionalities because the method provides a high level of control over material placement and processing conditions. This is achievable by extrusion of a preprocessed filament feedstock material along a predetermined path. However if fabrication of a multifunctional part relies only on conventional filament materials, it will require a different material for each unique functionality printed into the part. Carbon nanotubes (CNTs) are an attractive material for many applications due to their high specific strength as well as good electrical and thermal conductivity. The presence of this set of properties in a single material presents an opportunity to use one material to achieve multifunctionality in an additively manufactured part. This paper describes a recently developed method for processing continuous CNT yarn filaments into three-dimensional articles, and summarizes the mechanical, electrical, and sensing performance of the components fabricated in this way.

  6. Lightweight custom composite prosthetic components using an additive manufacturing-based molding technique.

    PubMed

    Leddy, Michael T; Belter, Joseph T; Gemmell, Kevin D; Dollar, Aaron M

    2015-01-01

    Additive manufacturing techniques are becoming more prominent and cost-effective as 3D printing becomes higher quality and more inexpensive. The idea of 3D printed prosthetics components promises affordable, customizable devices, but these systems currently have major shortcomings in durability and function. In this paper, we propose a fabrication method for custom composite prostheses utilizing additive manufacturing, allowing for customizability, as well the durability of professional prosthetics. The manufacturing process is completed using 3D printed molds in a multi-stage molding system, which creates a custom finger or palm with a lightweight epoxy foam core, a durable composite outer shell, and soft urethane gripping surfaces. The composite material was compared to 3D printed and aluminum materials using a three-point bending test to compare stiffness, as well as gravimetric measurements to compare weight. The composite finger demonstrates the largest stiffness with the lowest weight compared to other tested fingers, as well as having customizability and lower cost, proving to potentially be a substantial benefit to the development of upper-limb prostheses.

  7. The relationships between deformation mechanisms and mechanical properties of additively manufactured porous biomaterials.

    PubMed

    Kadkhodapour, J; Montazerian, H; Darabi, A Ch; Zargarian, A; Schmauder, S

    2017-06-01

    Modulating deformation mechanism through manipulating morphological parameters of scaffold internal pore architecture provides potential to tailor the overall mechanical properties under physiological loadings. Whereas cells sense local strains, cell differentiation is also impressed by the elastic deformations. In this paper, structure-property relations were developed for Ti6-Al-4V scaffolds designed based on triply periodic minimal surfaces. 10mm cubic scaffolds composed of 5×5×5 unit cells formed of F-RD (bending dominated) and I-WP (stretching dominated) architectures were additively manufactured at different volume fractions and subjected to compressive tests. The first stages of deformation for stretching dominated structure, was accompanied by bilateral layer-by-layer failure of unit cells owing to the buckling of micro-struts, while for bending dominated structure, namely F-RD, global shearing bands appeared since the shearing failure of struts in the internal architecture. Promoted mechanical properties were found for stretching dominated structure since the global orientation of struts were parallel to loading direction while inclination of struts diminished specific properties for bending dominated structure. Moreover, elastic-plastic deformation was computationally studied by applying Johnson-Cook damage model to the voxel-based models in FE analysis. Scaling analysis was performed for mechanical properties with respect to the relative density thereby failure mechanism was correlated to the constants of power law describing mechanical properties. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Reactive polymer fused deposition manufacturing

    DOEpatents

    Kunc, Vlastimil; Rios, Orlando; Love, Lonnie J.; Duty, Chad E.; Johs, Alexander

    2017-05-16

    Methods and compositions for additive manufacturing that include reactive or thermosetting polymers, such as urethanes and epoxies. The polymers are melted, partially cross-linked prior to the depositing, deposited to form a component object, solidified, and fully cross-linked. These polymers form networks of chemical bonds that span the deposited layers. Application of a directional electromagnetic field can be applied to aromatic polymers after deposition to align the polymers for improved bonding between the deposited layers.

  9. Additive-manufactured sandwich lattice structures: A numerical and experimental investigation

    NASA Astrophysics Data System (ADS)

    Fergani, Omar; Tronvoll, Sigmund; Brøtan, Vegard; Welo, Torgeir; Sørby, Knut

    2017-10-01

    The utilization of additive-manufactured lattice structures in engineered products is becoming more and more common as the competitiveness of AM as a production technology has increased during the past several years. Lattice structures may enable important weight reductions as well as open opportunities to build products with customized functional properties, thanks to the flexibility of AM for producing complex geometrical configurations. One of the most critical aspects related to taking AM into new application areas—such as safety critical products—is currently the limited understanding of the mechanical behavior of sandwich-based lattice structure mechanical under static and dynamic loading. In this study, we evaluate manufacturability of lattice structures and the impact of AM processing parameters on the structural behavior of this type of sandwich structures. For this purpose, we conducted static compression testing for a variety of geometry and manufacturing parameters. Further, the study discusses a numerical model capable of predicting the behavior of different lattice structure. A reasonably good correlation between the experimental and numerical results was observed.

  10. Advances in Additive Manufacturing

    DTIC Science & Technology

    2016-07-14

    of 3D - printed structures. Analysis examples will include quantification of tolerance differences between the designed and manufactured parts, void...15. SUBJECT TERMS 3-D printing , validation and verification, nondestructive inspection, print -on-the-move, prototyping 16. SECURITY CLASSIFICATION...researching the formation of AM-grade metal powder from battlefield scrap and operating base waste, 2) potential of 3-D printing with sand to make

  11. Multi-scale Microstructure Characterization for Improved Understanding of Microstructure-Property Relationship in Additive Manufacturing

    NASA Astrophysics Data System (ADS)

    Song, Hye Yun

    Additive manufacturing (AM) is the process for making 3-D objects by adding materials layer by layer. It can result in a marked reduction of the time and cost associated with designing and producing highly complex parts. Over the past decade, significant progress has been made in machine hardware and control software for process development to achieve dimensional accuracy and mitigate defects. On the other hand, the knowledge on microstructure-property relationship in the additively manufactured builds is still being established. In additive manufacturing, the interactions between the heat source and the material lead to a series of physical phenomena including localized heating, melting, solidification and micro-segregation, and cooling. Far-from-equilibrium microstructure can form as the material experiences a large number of repeated, rapid heating and cooling cycles (i.e. temperature gyrations) during depositions. The mechanical properties of additively manufactured parts are significantly influenced by their final microstructure. The overarching goal of the present research is to improve the fundamental understanding of microstructure-property relationship for AM parts. Specially, it is investigated the high-temperature creep strength of InconelRTM 718 (abbreviated as IN718 thereafter) fabricated by laser-powder bed fusion (L-PBF) AM. The specific objectives include (1) effect of support on the local microstructure, (2) microstructure evolution during post-built heat treatment, and (3) creep strength. Detailed microstructure characterization is performed using a multitude of tools including micro-hardness mapping, scanning electron microscope (SEM) along with electron backscatter diffraction (EBSD), and transmission electron microscope (TEM) for selected area diffraction (SAD) analysis and energy-dispersive X-ray spectroscopy (EDS). The characterized microstructure is correlated to the mechanical properties. Highlights of the research findings are discussed in

  12. Falcon: Visual analysis of large, irregularly sampled, and multivariate time series data in additive manufacturing

    DOE PAGES

    Steed, Chad A.; Halsey, William; Dehoff, Ryan; ...

    2017-02-16

    Flexible visual analysis of long, high-resolution, and irregularly sampled time series data from multiple sensor streams is a challenge in several domains. In the field of additive manufacturing, this capability is critical for realizing the full potential of large-scale 3D printers. Here, we propose a visual analytics approach that helps additive manufacturing researchers acquire a deep understanding of patterns in log and imagery data collected by 3D printers. Our specific goals include discovering patterns related to defects and system performance issues, optimizing build configurations to avoid defects, and increasing production efficiency. We introduce Falcon, a new visual analytics system thatmore » allows users to interactively explore large, time-oriented data sets from multiple linked perspectives. Falcon provides overviews, detailed views, and unique segmented time series visualizations, all with adjustable scale options. To illustrate the effectiveness of Falcon at providing thorough and efficient knowledge discovery, we present a practical case study involving experts in additive manufacturing and data from a large-scale 3D printer. The techniques described are applicable to the analysis of any quantitative time series, though the focus of this paper is on additive manufacturing.« less

  13. Falcon: Visual analysis of large, irregularly sampled, and multivariate time series data in additive manufacturing

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Steed, Chad A.; Halsey, William; Dehoff, Ryan

    Flexible visual analysis of long, high-resolution, and irregularly sampled time series data from multiple sensor streams is a challenge in several domains. In the field of additive manufacturing, this capability is critical for realizing the full potential of large-scale 3D printers. Here, we propose a visual analytics approach that helps additive manufacturing researchers acquire a deep understanding of patterns in log and imagery data collected by 3D printers. Our specific goals include discovering patterns related to defects and system performance issues, optimizing build configurations to avoid defects, and increasing production efficiency. We introduce Falcon, a new visual analytics system thatmore » allows users to interactively explore large, time-oriented data sets from multiple linked perspectives. Falcon provides overviews, detailed views, and unique segmented time series visualizations, all with adjustable scale options. To illustrate the effectiveness of Falcon at providing thorough and efficient knowledge discovery, we present a practical case study involving experts in additive manufacturing and data from a large-scale 3D printer. The techniques described are applicable to the analysis of any quantitative time series, though the focus of this paper is on additive manufacturing.« less

  14. Materials Testing and Cost Modeling for Composite Parts Through Additive Manufacturing

    DTIC Science & Technology

    2016-04-30

    FDM include plastic jet printing (PJP), fused filament modeling ( FFM ), and fused filament fabrication (FFF). FFF was coined by the RepRap project to...additive manufacturing processes? • Fused deposition modeling (FDM) trademarked by Stratasys • Fused filament modeling ( FFM ) and fused filament

  15. Additive Manufacturing: Ensuring Quality for Spacecraft Applications

    NASA Technical Reports Server (NTRS)

    Swanson, Theodore; Stephenson, Timothy

    2014-01-01

    Reliable manufacturing requires that material properties and fabrication processes be well defined in order to insure that the manufactured parts meet specified requirements. While this issue is now relatively straightforward for traditional processes such as subtractive manufacturing and injection molding, this capability is still evolving for AM products. Hence, one of the principal challenges within AM is in qualifying and verifying source material properties and process control. This issue is particularly critical for applications in harsh environments and demanding applications, such as spacecraft.

  16. A Multi-Scale, Multi-Physics Optimization Framework for Additively Manufactured Structural Components

    NASA Astrophysics Data System (ADS)

    El-Wardany, Tahany; Lynch, Mathew; Gu, Wenjiong; Hsu, Arthur; Klecka, Michael; Nardi, Aaron; Viens, Daniel

    This paper proposes an optimization framework enabling the integration of multi-scale / multi-physics simulation codes to perform structural optimization design for additively manufactured components. Cold spray was selected as the additive manufacturing (AM) process and its constraints were identified and included in the optimization scheme. The developed framework first utilizes topology optimization to maximize stiffness for conceptual design. The subsequent step applies shape optimization to refine the design for stress-life fatigue. The component weight was reduced by 20% while stresses were reduced by 75% and the rigidity was improved by 37%. The framework and analysis codes were implemented using Altair software as well as an in-house loading code. The optimized design was subsequently produced by the cold spray process.

  17. Cloud-Based Automated Design and Additive Manufacturing: A Usage Data-Enabled Paradigm Shift

    PubMed Central

    Lehmhus, Dirk; Wuest, Thorsten; Wellsandt, Stefan; Bosse, Stefan; Kaihara, Toshiya; Thoben, Klaus-Dieter; Busse, Matthias

    2015-01-01

    Integration of sensors into various kinds of products and machines provides access to in-depth usage information as basis for product optimization. Presently, this large potential for more user-friendly and efficient products is not being realized because (a) sensor integration and thus usage information is not available on a large scale and (b) product optimization requires considerable efforts in terms of manpower and adaptation of production equipment. However, with the advent of cloud-based services and highly flexible additive manufacturing techniques, these obstacles are currently crumbling away at rapid pace. The present study explores the state of the art in gathering and evaluating product usage and life cycle data, additive manufacturing and sensor integration, automated design and cloud-based services in manufacturing. By joining and extrapolating development trends in these areas, it delimits the foundations of a manufacturing concept that will allow continuous and economically viable product optimization on a general, user group or individual user level. This projection is checked against three different application scenarios, each of which stresses different aspects of the underlying holistic concept. The following discussion identifies critical issues and research needs by adopting the relevant stakeholder perspectives. PMID:26703606

  18. Cloud-Based Automated Design and Additive Manufacturing: A Usage Data-Enabled Paradigm Shift.

    PubMed

    Lehmhus, Dirk; Wuest, Thorsten; Wellsandt, Stefan; Bosse, Stefan; Kaihara, Toshiya; Thoben, Klaus-Dieter; Busse, Matthias

    2015-12-19

    Integration of sensors into various kinds of products and machines provides access to in-depth usage information as basis for product optimization. Presently, this large potential for more user-friendly and efficient products is not being realized because (a) sensor integration and thus usage information is not available on a large scale and (b) product optimization requires considerable efforts in terms of manpower and adaptation of production equipment. However, with the advent of cloud-based services and highly flexible additive manufacturing techniques, these obstacles are currently crumbling away at rapid pace. The present study explores the state of the art in gathering and evaluating product usage and life cycle data, additive manufacturing and sensor integration, automated design and cloud-based services in manufacturing. By joining and extrapolating development trends in these areas, it delimits the foundations of a manufacturing concept that will allow continuous and economically viable product optimization on a general, user group or individual user level. This projection is checked against three different application scenarios, each of which stresses different aspects of the underlying holistic concept. The following discussion identifies critical issues and research needs by adopting the relevant stakeholder perspectives.

  19. Tailoring the thermal conductivity of the powder bed in Electron Beam Melting (EBM) Additive Manufacturing.

    PubMed

    Smith, C J; Tammas-Williams, S; Hernandez-Nava, E; Todd, I

    2017-09-05

    Metallic powder bed additive manufacturing is capable of producing complex, functional parts by repeatedly depositing thin layers of powder particles atop of each other whilst selectively melting the corresponding part cross-section into each layer. A weakness with this approach arises when melting overhanging features, which have no prior melted material directly beneath them. This is due to the lower thermal conductivity of the powder relative to solid material, which as a result leads to an accumulation of heat and thus distortion. The Electron Beam Melting (EBM) process alleviates this to some extent as the powder must first be sintered (by the beam itself) before it is melted, which results in the added benefit of increasing the thermal conductivity. This study thus sought to investigate to what extent the thermal conductivity of local regions in a titanium Ti-6Al-4V powder bed could be varied by imparting more energy from the beam. Thermal diffusivity and density measurements were taken of the resulting sintered samples, which ranged from being loosely to very well consolidated. It was found that the calculated thermal conductivity at two temperatures, 40 and 730 °C, was more than doubled over the range of input energies explored.

  20. Microstructure characterisation of Ti-6Al-4V from different additive manufacturing processes

    NASA Astrophysics Data System (ADS)

    Neikter, M.; Åkerfeldt, P.; Pederson, R.; Antti, M.-L.

    2017-10-01

    The focus of this work has been microstructure characterisation of Ti-6Al-4V manufactured by five different additive manufacturing (AM) processes. The microstructure features being characterised are the prior β size, grain boundary α and α lath thickness. It was found that material manufactured with powder bed fusion processes has smaller prior β grains than the material from directed energy deposition processes. The AM processes with fast cooling rate render in thinner α laths and also thinner, and in some cases discontinuous, grain boundary α. Furthermore, it has been observed that material manufactured with the directed energy deposition processes has parallel bands, except for one condition when the parameters were changed, while the powder bed fusion processes do not have any parallel bands.

  1. Additively Manufactured Metals in Oxygen Systems Project

    NASA Technical Reports Server (NTRS)

    Tylka, Jonathan

    2015-01-01

    Metals produced by additive manufacturing methods, such as Powder Bed Fusion Technology, are now mature enough to be considered for qualification in human spaceflight oxygen systems. The mechanical properties of metals produced through AM processes are being systematically studied. However, it is unknown whether AM metals in oxygen applications may present an increased risk of flammability or ignition as compared to wrought metals of the same metallurgical composition due to increased porosity. Per NASA-STD-6001B materials to be used in oxygen system applications shall be based on flammability and combustion test data, followed by a flammability assessment. Without systematic flammability and ignition testing in oxygen there is no credible method for NASA to accurately evaluate the risk of using AM metals in oxygen systems.

  2. Direct fabrication of bio-inspired gecko-like geometries with vat polymerization additive manufacturing method

    NASA Astrophysics Data System (ADS)

    Davoudinejad, A.; Ribo, M. M.; Pedersen, D. B.; Islam, A.; Tosello, G.

    2018-08-01

    Functional surfaces have proven their potential to solve many engineering problems, attracting great interest among the scientific community. Bio-inspired multi-hierarchical micro-structures grant the surfaces with new properties, such as hydrophobicity, adhesion, unique optical properties and so on. The geometry and fabrication of these surfaces are still under research. In this study, the feasibility of using direct fabrication of microscale features by additive manufacturing (AM) processes was investigated. The investigation was carried out using a specifically designed vat photopolymerization AM machine-tool suitable for precision manufacturing at the micro dimensional scale which has previously been developed, built and validated at the Technical University of Denmark. It was shown that it was possible to replicate a simplified surface inspired by the Tokay gecko, the geometry was previously designed and replicated by a complex multi-step micromanufacturing method extracted from the literature and used as benchmark. Ultimately, the smallest printed features were analyzed by conducting a sensitivity analysis to obtain the righteous parameters in terms of layer thickness and exposure time. Moreover, two more intricate designs were fabricated with the same parameters to assess the surfaces functionality by its wettability. The surface with increased density and decreased feature size showed a water contact angle (CA) of 124°  ±  0.10°, agreeing with the Cassie–Baxter model. These results indicate the possibility of using precision AM for a rapid, easy and reliable fabrication method for functional surfaces.

  3. Powder bed charging during electron-beam additive manufacturing

    DOE PAGES

    Cordero, Zachary C.; Meyer, Harry M.; Nandwana, Peeyush; ...

    2016-11-18

    Electrons injected into the build envelope during powder-bed electron-beam additive manufacturing can accumulate on the irradiated particles and cause them to repel each other. Furthermore, these electrostatic forces can grow so large that they drive the particles out of the build envelope in a process known as smoking. Here, a model of powder bed charging is formulated and used to develop criteria that predict the conditions under which the powder bed will smoke. These criteria suggest dependences on particle size, pre-heat temperature, and process parameters that align closely with those observed in practice.

  4. Simulation based optimized beam velocity in additive manufacturing

    NASA Astrophysics Data System (ADS)

    Vignat, Frédéric; Béraud, Nicolas; Villeneuve, François

    2017-08-01

    Manufacturing good parts with additive technologies rely on melt pool dimension and temperature and are controlled by manufacturing strategies often decided on machine side. Strategies are built on beam path and variable energy input. Beam path are often a mix of contour and hatching strategies filling the contours at each slice. Energy input depend on beam intensity and speed and is determined from simple thermal models to control melt pool dimensions and temperature and ensure porosity free material. These models take into account variation in thermal environment such as overhanging surfaces or back and forth hatching path. However not all the situations are correctly handled and precision is limited. This paper proposes new method to determine energy input from full built chamber 3D thermal simulation. Using the results of the simulation, energy is modified to keep melt pool temperature in a predetermined range. The paper present first an experimental method to determine the optimal range of temperature. In a second part the method to optimize the beam speed from the simulation results is presented. Finally, the optimized beam path is tested in the EBM machine and built part are compared with part built with ordinary beam path.

  5. Numerical simulation of complex part manufactured by selective laser melting process

    NASA Astrophysics Data System (ADS)

    Van Belle, Laurent

    2017-10-01

    Selective Laser Melting (SLM) process belonging to the family of the Additive Manufacturing (AM) technologies, enable to build parts layer by layer, from metallic powder and a CAD model. Physical phenomena that occur in the process have the same issues as conventional welding. Thermal gradients generate significant residual stresses and distortions in the parts. Moreover, the large and complex parts to manufacturing, accentuate the undesirable effects. Therefore, it is essential for manufacturers to offer a better understanding of the process and to ensure production reliability of parts with high added value. This paper focuses on the simulation of manufacturing turbine by SLM process in order to calculate residual stresses and distortions. Numerical results will be presented.

  6. Biofabrication of customized bone grafts by combination of additive manufacturing and bioreactor knowhow.

    PubMed

    Costa, Pedro F; Vaquette, Cédryck; Baldwin, Jeremy; Chhaya, Mohit; Gomes, Manuela E; Reis, Rui L; Theodoropoulos, Christina; Hutmacher, Dietmar W

    2014-09-01

    This study reports on an original concept of additive manufacturing for the fabrication of tissue engineered constructs (TEC), offering the possibility of concomitantly manufacturing a customized scaffold and a bioreactor chamber to any size and shape. As a proof of concept towards the development of anatomically relevant TECs, this concept was utilized for the design and fabrication of a highly porous sheep tibia scaffold around which a bioreactor chamber of similar shape was simultaneously built. The morphology of the bioreactor/scaffold device was investigated by micro-computed tomography and scanning electron microscopy confirming the porous architecture of the sheep tibiae as opposed to the non-porous nature of the bioreactor chamber. Additionally, this study demonstrates that both the shape, as well as the inner architecture of the device can significantly impact the perfusion of fluid within the scaffold architecture. Indeed, fluid flow modelling revealed that this was of significant importance for controlling the nutrition flow pattern within the scaffold and the bioreactor chamber, avoiding the formation of stagnant flow regions detrimental for in vitro tissue development. The bioreactor/scaffold device was dynamically seeded with human primary osteoblasts and cultured under bi-directional perfusion for two and six weeks. Primary human osteoblasts were observed homogenously distributed throughout the scaffold, and were viable for the six week culture period. This work demonstrates a novel application for additive manufacturing in the development of scaffolds and bioreactors. Given the intrinsic flexibility of the additive manufacturing technology platform developed, more complex culture systems can be fabricated which would contribute to the advances in customized and patient-specific tissue engineering strategies for a wide range of applications.

  7. Big Area Additive Manufacturing of High Performance Bonded NdFeB Magnets

    NASA Astrophysics Data System (ADS)

    Li, Ling; Tirado, Angelica; Nlebedim, I. C.; Rios, Orlando; Post, Brian; Kunc, Vlastimil; Lowden, R. R.; Lara-Curzio, Edgar; Fredette, Robert; Ormerod, John; Lograsso, Thomas A.; Paranthaman, M. Parans

    2016-10-01

    Additive manufacturing allows for the production of complex parts with minimum material waste, offering an effective technique for fabricating permanent magnets which frequently involve critical rare earth elements. In this report, we demonstrate a novel method - Big Area Additive Manufacturing (BAAM) - to fabricate isotropic near-net-shape NdFeB bonded magnets with magnetic and mechanical properties comparable or better than those of traditional injection molded magnets. The starting polymer magnet composite pellets consist of 65 vol% isotropic NdFeB powder and 35 vol% polyamide (Nylon-12). The density of the final BAAM magnet product reached 4.8 g/cm3, and the room temperature magnetic properties are: intrinsic coercivity Hci = 688.4 kA/m, remanence Br = 0.51 T, and energy product (BH)max = 43.49 kJ/m3 (5.47 MGOe). In addition, tensile tests performed on four dog-bone shaped specimens yielded an average ultimate tensile strength of 6.60 MPa and an average failure strain of 4.18%. Scanning electron microscopy images of the fracture surfaces indicate that the failure is primarily related to the debonding of the magnetic particles from the polymer binder. The present method significantly simplifies manufacturing of near-net-shape bonded magnets, enables efficient use of rare earth elements thus contributing towards enriching the supply of critical materials.

  8. Big area additive manufacturing of high performance bonded NdFeB magnets

    DOE PAGES

    Li, Ling; Tirado, Angelica; Nlebedim, I. C.; ...

    2016-10-31

    Additive manufacturing allows for the production of complex parts with minimum material waste, offering an effective technique for fabricating permanent magnets which frequently involve critical rare earth elements. In this report, we demonstrate a novel method - Big Area Additive Manufacturing (BAAM) - to fabricate isotropic near-net-shape NdFeB bonded magnets with magnetic and mechanical properties comparable or better than those of traditional injection molded magnets. The starting polymer magnet composite pellets consist of 65 vol% isotropic NdFeB powder and 35 vol% polyamide (Nylon-12). The density of the final BAAM magnet product reached 4.8 g/cm3, and the room temperature magnetic propertiesmore » are: intrinsic coercivity Hci = 688.4 kA/m, remanence B r = 0.51 T, and energy product (BH) max = 43.49 kJ/m 3 (5.47 MGOe). In addition, tensile tests performed on four dog-bone shaped specimens yielded an average ultimate tensile strength of 6.60 MPa and an average failure strain of 4.18%. Scanning electron microscopy images of the fracture surfaces indicate that the failure is primarily related to the debonding of the magnetic particles from the polymer binder. As a result, the present method significantly simplifies manufacturing of near-net-shape bonded magnets, enables efficient use of rare earth elements thus contributing towards enriching the supply of critical materials.« less

  9. Big area additive manufacturing of high performance bonded NdFeB magnets

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Li, Ling; Tirado, Angelica; Nlebedim, I. C.

    Additive manufacturing allows for the production of complex parts with minimum material waste, offering an effective technique for fabricating permanent magnets which frequently involve critical rare earth elements. In this report, we demonstrate a novel method - Big Area Additive Manufacturing (BAAM) - to fabricate isotropic near-net-shape NdFeB bonded magnets with magnetic and mechanical properties comparable or better than those of traditional injection molded magnets. The starting polymer magnet composite pellets consist of 65 vol% isotropic NdFeB powder and 35 vol% polyamide (Nylon-12). The density of the final BAAM magnet product reached 4.8 g/cm3, and the room temperature magnetic propertiesmore » are: intrinsic coercivity Hci = 688.4 kA/m, remanence B r = 0.51 T, and energy product (BH) max = 43.49 kJ/m 3 (5.47 MGOe). In addition, tensile tests performed on four dog-bone shaped specimens yielded an average ultimate tensile strength of 6.60 MPa and an average failure strain of 4.18%. Scanning electron microscopy images of the fracture surfaces indicate that the failure is primarily related to the debonding of the magnetic particles from the polymer binder. As a result, the present method significantly simplifies manufacturing of near-net-shape bonded magnets, enables efficient use of rare earth elements thus contributing towards enriching the supply of critical materials.« less

  10. In vivo XCT bone characterization of lattice structured implants fabricated by additive manufacturing.

    PubMed

    Obaton, A-F; Fain, J; Djemaï, M; Meinel, D; Léonard, F; Mahé, E; Lécuelle, B; Fouchet, J-J; Bruno, G

    2017-08-01

    Several cylindrical specimens and dental implants, presenting diagonal lattice structures with different cell sizes (600, 900 and 1200 μm) were additively manufactured by selective laser melting process. Then they were implanted for two months in a sheep. After removal, they were studied by Archimedes' method as well as X-ray computed tomography in order to assess the penetration of bone into the lattice. We observed that the additive manufactured parts were geometrically conformed to the theoretical specifications. However, several particles were left adhering to the surface of the lattice, thereby partly or entirely obstructing the cells. Nevertheless, bone penetration was clearly visible. We conclude that the 900 μm lattice cell size is more favourable to bone penetration than the 1200 μm lattice cell size, as the bone penetration is 84% for 900 μm against 54% for 1200 μm cell structures. The lower bone penetration value for the 1200 μm lattice cell could possibly be attributed to the short residence time in the sheep. Our results lead to the conclusion that lattice implants additively manufactured by selective laser melting enable better bone integration.

  11. Structure/property (constitutive and dynamic strength/damage) characterization of additively manufactured 316L SS

    NASA Astrophysics Data System (ADS)

    Gray, G. T., III; Livescu, V.; Rigg, P. A.; Trujillo, C. P.; Cady, C. M.; Chen, S. R.; Carpenter, J. S.; Lienert, T. J.; Fensin, S.

    2015-09-01

    For additive manufacturing (AM), the certification and qualification paradigm needs to evolve as there exists no "ASTM-type" additive manufacturing certified process or AM-material produced specifications. Accordingly, utilization of AM materials to meet engineering applications requires quantification of the constitutive properties of these evolving materials in comparison to conventionally-manufactured metals and alloys. Cylinders of 316L SS were produced using a LENS MR-7 laser additive manufacturing system from Optomec (Albuquerque, NM) equipped with a 1kW Yb-fiber laser. The microstructure of the AM-316L SS is detailed in both the as-built condition and following heat-treatments designed to obtain full recrystallization. The constitutive behavior as a function of strain rate and temperature is presented and compared to that of nominal annealed wrought 316L SS plate. The dynamic damage evolution and failure response of all three materials was probed using flyer-plate impact driven spallation experiments at a peak stress of 4.5 GPa to examine incipient spallation response. The spall strength of AM-produced 316L SS was found to be very similar for the peak shock stress studied to that of annealed wrought or AM-316L SS following recrystallization. The damage evolution as a function of microstructure was characterized using optical metallography.

  12. Manufacturing of GLARE Parts and Structures

    NASA Astrophysics Data System (ADS)

    Sinke, J.

    2003-07-01

    GLARE is a hybrid material consisting of alternating layers of metal sheets and composite layers, requiring special attention when manufacturing of parts and structures is concerned. On one hand the applicable manufacturing processes for GLARE are limited, on the other hand, due to the constituents and composition of the laminate, it offers new opportunities for production. One of the opportunities is the manufacture of very large skin panels by lay-up techniques. Lay-up techniques are common for full composites, but uncommon for metallic structures. Nevertheless, large GLARE skin panels are made by lay-up processes. In addition, the sequences of forming and laminating processes, that can be selected, offer manufacturing options that are not applicable to metals or full composites. With respect to conventional manufacturing processes, the possibilities for Fibre Metal Laminates in general, are limited. The limits are partly due to the different failure modes, partly due to the properties of the constituents in the laminate. For machining processes: the wear of the cutting tools during machining operations of GLARE stems from the abrasive nature of the glass fibres. For the forming processes: the limited formability, expressed by a small failure strain, is related to the glass fibres. However, although these manufacturing issues may restrict the use of manufacturing processes for FMLs, application of these laminates in aircraft is not hindered.

  13. Cooling Rate Determination in Additively Manufactured Aluminum Alloy 2219

    NASA Astrophysics Data System (ADS)

    Brice, Craig A.; Dennis, Noah

    2015-05-01

    Metallic additive manufacturing processes generally utilize a conduction mode, welding-type approach to create beads of deposited material that can be arranged into a three-dimensional structure. As with welding, the cooling rates in the molten pool are relatively rapid compared to traditional casting techniques. Determination of the cooling rate in the molten pool is critical for predicting the solidified microstructure and resultant properties. In this experiment, wire-fed electron beam additive manufacturing was used to melt aluminum alloy 2219 under different thermal boundary conditions. The dendrite arm spacing was measured in the remelted material, and this information was used to estimate cooling rates in the molten pool based on established empirical relationships. The results showed that the thermal boundary conditions have a significant effect on the resulting cooling rate in the molten pool. When thermal conduction is limited due to a small thermal sink, the dendrite arm spacing varies between 15 and 35 µm. When thermal conduction is active, the dendrite arm spacing varies between 6 and 12 µm. This range of dendrite arm spacing implies cooling rates ranging from 5 to 350 K/s. Cooling rates can vary greatly as thermal conditions change during deposition. A cooling rate at the higher end of the range could lead to significant deviation from microstructural equilibrium during solidification.

  14. Utilization of Additive Manufacturing in Evaluating the Performance of Internally Defected Materials

    NASA Astrophysics Data System (ADS)

    Mourad, A.-H. I.; Ghazal, A. M.; Syam, M. M.; Qadi, O. D. Al; Jassmi, H. Al

    2018-05-01

    The elimination of internal defects in a material present in the raw material or generated during the manufacturing or service is difficult. The inclusions of the defects have an adverse effect on the load bearing capacity. The presence of the cracks subjected to a specific orientation in materials or machinery can cause devastating unexpected failure during operation. Analysis of the failure in the components with cracks is more confined to analytical and numerical evaluation. The experimental evaluation has been tedious due to the complexity of replicating the actual defected component. The potential of additive manufacturing in developing user-defined components with cracks for the experimental evaluation is explored in this research. The present research investigated the effect of the internal elliptical cracks aligned at different orientations on the mechanical performance of polylactic acid (Green filament). The Fusion Deposition Method was utilized for the development of the standard tensile specimens with internal elliptical crack oriented at 0°, 45° and 90° using UltiMaker 2. The results proved that there is a considerable reduction in the load bearing capacity due to the presence of the cracks. The maximum load bearing capacity decreased by 15.01% for the specimen with crack inclined at 0° to the lateral axis compared to crack- free specimen. The nature of the fracture and the stress-strain graph evidently showcase the brittle nature of the material. The SEM image of the fractured region proved the phenomenal characteristics such as strong adhesion between the layers and the proper material flow. In the light of the results of this work, it can be concluded that the 3-D printing methodology is effective for evaluating the mechanical performance of the internally defected material.

  15. Composite scaffolds for osteochondral repair obtained by combination of additive manufacturing, leaching processes and hMSC-CM functionalization.

    PubMed

    Díaz Lantada, Andrés; Alarcón Iniesta, Hernán; García-Ruíz, Josefa Predestinación

    2016-02-01

    Articular repair is a relevant and challenging area for the emerging fields of tissue engineering and biofabrication. The need of significant gradients of properties, for the promotion of osteochondral repair, has led to the development of several families of composite biomaterials and scaffolds, using different effective approaches, although a perfect solution has not yet been found. In this study we present the design, modeling, rapid manufacturing and in vitro testing of a composite scaffold aimed at osteochondral repair. The presented composite scaffold stands out for having a functional gradient of density and stiffness in the bony phase, obtained in titanium by means of computer-aided design combined with additive manufacture using selective laser sintering. The chondral phase is obtained by sugar leaching, using a PDMS matrix and sugar as porogen, and is joined to the bony phase during the polymerization of PDMS, therefore avoiding the use of supporting adhesives or additional intermediate layers. The mechanical performance of the construct is biomimetic and the stiffness values of the bony and chondral phases can be tuned to the desired applications, by means of controlled modifications of different parameters. A human mesenchymal stem cell (h-MSC) conditioned medium (CM) is used for improving scaffold response. Cell culture results provide relevant information regarding the viability of the composite scaffolds used. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Computational Fluid Dynamics and Additive Manufacturing to Diagnose and Treat Cardiovascular Disease.

    PubMed

    Randles, Amanda; Frakes, David H; Leopold, Jane A

    2017-11-01

    Noninvasive engineering models are now being used for diagnosing and planning the treatment of cardiovascular disease. Techniques in computational modeling and additive manufacturing have matured concurrently, and results from simulations can inform and enable the design and optimization of therapeutic devices and treatment strategies. The emerging synergy between large-scale simulations and 3D printing is having a two-fold benefit: first, 3D printing can be used to validate the complex simulations, and second, the flow models can be used to improve treatment planning for cardiovascular disease. In this review, we summarize and discuss recent methods and findings for leveraging advances in both additive manufacturing and patient-specific computational modeling, with an emphasis on new directions in these fields and remaining open questions. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. A Novel Method for Fabricating Additive Manufactured Lightweight, Optical Quality Metallic Mirrors

    DTIC Science & Technology

    2016-01-04

    lighter  mirrors  can  lead to great reductions of mass in full systems [3,4].    The state of the art in this industry is ULE™,  Zerodur ™, or beryllium...1    A Novel Method for Fabricating Additive Manufactured  Lightweight, Optical Quality Metallic  Mirrors   Michael Stern, Joseph Bari  Distribution A...metallic  mirrors  fabricated by growing an additive manufactured blank, post  processing the faces, coating with electroless nickel, and diamond turning

  18. Using Additive Manufacturing to Print a CubeSat Propulsion System

    NASA Technical Reports Server (NTRS)

    Marshall, William M.

    2015-01-01

    CubeSats are increasingly being utilized for missions traditionally ascribed to larger satellites CubeSat unit (1U) defined as 10 cm x 10 cm x 11 cm. Have been built up to 6U sizes. CubeSats are typically built up from commercially available off-the-shelf components, but have limited capabilities. By using additive manufacturing, mission specific capabilities (such as propulsion), can be built into a system. This effort is part of STMD Small Satellite program Printing the Complete CubeSat. Interest in propulsion concepts for CubeSats is rapidly gaining interest-Numerous concepts exist for CubeSat scale propulsion concepts. The focus of this effort is how to incorporate into structure using additive manufacturing. End-use of propulsion system dictates which type of system to develop-Pulse-mode RCS would require different system than a delta-V orbital maneuvering system. Team chose an RCS system based on available propulsion systems and feasibility of printing using a materials extrusion process. Initially investigated a cold-gas propulsion system for RCS applications-Materials extrusion process did not permit adequate sealing of part to make this a functional approach.

  19. Compliance and control characteristics of an additive manufactured-flexure stage

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lee, ChaBum; Tarbutton, Joshua A.

    2015-04-15

    This paper presents a compliance and positioning control characteristics of additive manufactured-nanopositioning system consisted of the flexure mechanism and voice coil motor (VCM). The double compound notch type flexure stage was designed to utilize the elastic deformation of two symmetrical four-bar mechanisms to provide a millimeter-level working range. Additive manufacturing (AM) process, stereolithography, was used to fabricate the flexure stage. The AM stage was inspected by using 3D X-ray computerized tomography scanner: air-voids and shape irregularity. The compliance, open-loop resonance peak, and damping ratio of the AM stage were measured 0.317 mm/N, 80 Hz, and 0.19, respectively. The AM stagemore » was proportional-integral-derivative positioning feedback-controlled and the capacitive type sensor was used to measure the displacement. As a result, the AM flexure mechanism was successfully 25 nm positioning controlled within 500 μm range. The resonance peak was found approximately at 280 Hz in closed-loop. This research showed that the AM flexure mechanism and the VCM can provide millimeter range with high precision and can be a good alternative to an expensive metal-based flexure mechanism and piezoelectric transducer.« less

  20. Evaluation of marginal and internal gap of three-unit metal framework according to subtractive manufacturing and additive manufacturing of CAD/CAM systems

    PubMed Central

    Kim, Dong-Yeon; Kim, Eo-Bin; Kim, Hae-Young; Kim, Ji-Hwan

    2017-01-01

    PURPOSE To evaluate the fit of a three-unit metal framework of fixed dental prostheses made by subtractive and additive manufacturing. MATERIALS AND METHODS One master model of metal was fabricated. Twenty silicone impressions were made on the master die, working die of 10 poured with Type 4 stone, and working die of 10 made of scannable stone. Ten three-unit wax frameworks were fabricated by wax-up from Type IV working die. Stereolithography files of 10 three-unit frameworks were obtained using a model scanner and three-dimensional design software on a scannable working die. The three-unit wax framework was fabricated using subtractive manufacturing (SM) by applying the prepared stereolithography file, and the resin framework was fabricated by additive manufacturing (AM); both used metal alloy castings for metal frameworks. Marginal and internal gap were measured using silicone replica technique and digital microscope. Measurement data were analyzed by Kruskal-Wallis H test and Mann-Whitney U-test (α=.05). RESULTS The lowest and highest gaps between premolar and molar margins were in the SM group and the AM group, respectively. There was a statistically significant difference in the marginal gap among the 3 groups (P<.001). In the marginal area where pontic was present, the largest gap was 149.39 ± 42.30 µm in the AM group, and the lowest gap was 24.40 ± 11.92 µm in the SM group. CONCLUSION Three-unit metal frameworks made by subtractive manufacturing are clinically applicable. However, additive manufacturing requires more research to be applied clinically. PMID:29279766

  1. Evaluation of marginal and internal gap of three-unit metal framework according to subtractive manufacturing and additive manufacturing of CAD/CAM systems.

    PubMed

    Kim, Dong-Yeon; Kim, Eo-Bin; Kim, Hae-Young; Kim, Ji-Hwan; Kim, Woong-Chul

    2017-12-01

    To evaluate the fit of a three-unit metal framework of fixed dental prostheses made by subtractive and additive manufacturing. One master model of metal was fabricated. Twenty silicone impressions were made on the master die, working die of 10 poured with Type 4 stone, and working die of 10 made of scannable stone. Ten three-unit wax frameworks were fabricated by wax-up from Type IV working die. Stereolithography files of 10 three-unit frameworks were obtained using a model scanner and three-dimensional design software on a scannable working die. The three-unit wax framework was fabricated using subtractive manufacturing (SM) by applying the prepared stereolithography file, and the resin framework was fabricated by additive manufacturing (AM); both used metal alloy castings for metal frameworks. Marginal and internal gap were measured using silicone replica technique and digital microscope. Measurement data were analyzed by Kruskal-Wallis H test and Mann-Whitney U-test (α=.05). The lowest and highest gaps between premolar and molar margins were in the SM group and the AM group, respectively. There was a statistically significant difference in the marginal gap among the 3 groups ( P <.001). In the marginal area where pontic was present, the largest gap was 149.39 ± 42.30 µm in the AM group, and the lowest gap was 24.40 ± 11.92 µm in the SM group. Three-unit metal frameworks made by subtractive manufacturing are clinically applicable. However, additive manufacturing requires more research to be applied clinically.

  2. Finite element simulation and experimental verification of ultrasonic non-destructive inspection of defects in additively manufactured materials

    NASA Astrophysics Data System (ADS)

    Taheri, H.; Koester, L.; Bigelow, T.; Bond, L. J.

    2018-04-01

    Industrial applications of additively manufactured components are increasing quickly. Adequate quality control of the parts is necessary in ensuring safety when using these materials. Base material properties, surface conditions, as well as location and size of defects are some of the main targets for nondestructive evaluation of additively manufactured parts, and the problem of adequate characterization is compounded given the challenges of complex part geometry. Numerical modeling can allow the interplay of the various factors to be studied, which can lead to improved measurement design. This paper presents a finite element simulation verified by experimental results of ultrasonic waves scattering from flat bottom holes (FBH) in additive manufacturing materials. A focused beam immersion ultrasound transducer was used for both the modeling and simulations in the additive manufactured samples. The samples were SS17 4 PH steel samples made by laser sintering in a powder bed.

  3. 3D/Additive Printing Manufacturing: A Brief History and Purchasing Guide

    ERIC Educational Resources Information Center

    Hughes, Bill; Wilson, Greg

    2016-01-01

    3D printing is recognized as a collection of technologies known as rapid prototyping, solid freeform fabrication, and most commonly, additive manufacturing (AM). With these emerging technologies it is possible to print (but not limited to): architectural models, discontinued car-part foundry patterns, industry-wide prototypes, human tissues, the…

  4. Dimensionless numbers in additive manufacturing

    NASA Astrophysics Data System (ADS)

    Mukherjee, T.; Manvatkar, V.; De, A.; DebRoy, T.

    2017-02-01

    The effects of many process variables and alloy properties on the structure and properties of additively manufactured parts are examined using four dimensionless numbers. The structure and properties of components made from 316 Stainless steel, Ti-6Al-4V, and Inconel 718 powders for various dimensionless heat inputs, Peclet numbers, Marangoni numbers, and Fourier numbers are studied. Temperature fields, cooling rates, solidification parameters, lack of fusion defects, and thermal strains are examined using a well-tested three-dimensional transient heat transfer and fluid flow model. The results show that lack of fusion defects in the fabricated parts can be minimized by strengthening interlayer bonding using high values of dimensionless heat input. The formation of harmful intermetallics such as laves phases in Inconel 718 can be suppressed using low heat input that results in a small molten pool, a steep temperature gradient, and a fast cooling rate. Improved interlayer bonding can be achieved at high Marangoni numbers, which results in vigorous circulation of liquid metal, larger pool dimensions, and greater depth of penetration. A high Fourier number ensures rapid cooling, low thermal distortion, and a high ratio of temperature gradient to the solidification growth rate with a greater tendency of plane front solidification.

  5. Additive manufacture (3d printing) of plasma diagnostic components and assemblies for fusion experiments

    NASA Astrophysics Data System (ADS)

    Sieck, Paul; Woodruff, Simon; Stuber, James; Romero-Talamas, Carlos; Rivera, William; You, Setthivoine; Card, Alexander

    2015-11-01

    Additive manufacturing (or 3D printing) is now becoming sufficiently accurate with a large range of materials for use in printing sensors needed universally in fusion energy research. Decreasing production cost and significantly lowering design time of energy subsystems would realize significant cost reduction for standard diagnostics commonly obtained through research grants. There is now a well-established set of plasma diagnostics, but these expensive since they are often highly complex and require customization, sometimes pace the project. Additive manufacturing (3D printing) is developing rapidly, including open source designs. Basic components can be printed for (in some cases) less than 1/100th costs of conventional manufacturing. We have examined the impact that AM can have on plasma diagnostic cost by taking 15 separate diagnostics through an engineering design using Conventional Manufacturing (CM) techniques to determine costs of components and labor costs associated with getting the diagnostic to work as intended. With that information in hand, we set about optimizing the design to exploit the benefits of AM. Work performed under DOE Contract DE-SC0011858.

  6. Fatigue crack propagation in additively manufactured porous biomaterials.

    PubMed

    Hedayati, R; Amin Yavari, S; Zadpoor, A A

    2017-07-01

    Additively manufactured porous titanium implants, in addition to preserving the excellent biocompatible properties of titanium, have very small stiffness values comparable to those of natural bones. Although usually loaded in compression, biomedical implants can also be under tensional, shear, and bending loads which leads to crack initiation and propagation in their critical points. In this study, the static and fatigue crack propagation in additively manufactured porous biomaterials with porosities between 66% and 84% is investigated using compact-tension (CT) samples. The samples were made using selective laser melting from Ti-6Al-4V and were loaded in tension (in static study) and tension-tension (in fatigue study) loadings. The results showed that displacement accumulation diagram obtained for different CT samples under cyclic loading had several similarities with the corresponding diagrams obtained for cylindrical samples under compression-compression cyclic loadings (in particular, it showed a two-stage behavior). For a load level equaling 50% of the yield load, both the CT specimens studied here and the cylindrical samples we had tested under compression-compression cyclic loading elsewhere exhibited similar fatigue lives of around 10 4 cycles. The test results also showed that for the same load level of 0.5F y , the lower density porous structures demonstrate relatively longer lives than the higher-density ones. This is because the high bending stresses in high-density porous structures gives rise to local Mode-I crack opening in the rough external surface of the struts which leads to quicker formation and propagation of the cracks. Under both the static and cyclic loading, all the samples showed crack pathways which were not parallel to but made 45 ° angles with respect to the notch direction. This is due to the fact that in the rhombic dodecahedron unit cell, the weakest struts are located in 45 ° direction with respect to the notch direction

  7. Dropwise additive manufacturing of pharmaceutical products for amorphous and self emulsifying drug delivery systems.

    PubMed

    Içten, Elçin; Purohit, Hitesh S; Wallace, Chelsey; Giridhar, Arun; Taylor, Lynne S; Nagy, Zoltan K; Reklaitis, Gintaras V

    2017-05-30

    The improvements in healthcare systems and the advent of the precision medicine initiative have created the need to develop more innovative manufacturing methods for the delivery and production of individualized dosing and personalized treatments. In accordance with the changes observed in healthcare systems towards more innovative therapies, this paper presents dropwise additive manufacturing of pharmaceutical products (DAMPP) for small scale, distributed manufacturing of individualized dosing as an alternative to conventional manufacturing methods A dropwise additive manufacturing process for amorphous and self-emulsifying drug delivery systems is reported, which utilizes drop-on-demand printing technology for automated and controlled deposition of melt-based formulations onto inert tablets. The advantages of drop on demand technology include reproducible production of droplets with adjustable sizing and high placement accuracy, which enable production of individualized dosing even for low dose and high potency drugs. Flexible use of different formulations, such as lipid-based formulations, allows enhancement of the solubility of poorly water soluble and highly lipophilic drugs with DAMPP. Here, DAMPP is used to produce solid oral dosage forms from melts of an active pharmaceutical ingredient and a surfactant. The dosage forms are analyzed to show the amorphous nature, self-emulsifying drug delivery system characteristics and dissolution behavior of these formulations. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Reconstruction of an Extensive Midfacial Defect Using Additive Manufacturing Techniques.

    PubMed

    Fernandes, Nelson; van den Heever, Jacobus; Hoogendijk, Christiaan; Botha, Sarel; Booysen, Gerrie; Els, Johan

    2016-10-01

    Malignant peripheral nerve sheath tumors are extremely rare tumors arising in peripheral nerves. Only 17 cases involving the trigeminal nerve have ever been reported. These tumors have a very poor prognosis and very high rates of recurrence and metastases. Their recommended treatment involves complete tumor resection followed by radiation. This can be problematic in the head and neck region. We present a clinical case involving a 33-year-old female patient presenting with a slow-growing, exophytic mass of the anterior maxilla. Incisional biopsy and subsequent histological examination revealed a diagnosis of a malignant peripheral nerve sheath tumor. Surgical resection involved a complete maxillectomy, rhinectomy, and resection of the upper lip and aspects of the left and right cheeks. Reconstruction of the subsequent defect incorporated the placement of four zygomatic oncology implants to aid in retention of a facial prosthesis. These implants, however, were subsequently lost; and an anatomical model of the hard tissues was manufactured via 3D printing. This model was used to design and manufacture a titanium frame (customized implant) for the patient. The frame was then fixated and secured intraoperatively with 21 cortical screws. A maxillary denture and silicone facial prosthesis were also made to fit onto this frame. This is the first known case where additive manufacturing, via the use of rapid prototyping and 3D printing, was employed to manufacture a facial prosthesis. © 2016 by the American College of Prosthodontists.

  9. 76 FR 82308 - Guidance for Industry: Current Good Tissue Practice and Additional Requirements for Manufacturers...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-30

    ... Cells, Tissues, and Cellular and Tissue-Based Products; Availability AGENCY: Food and Drug... Requirements for Manufacturers of Human Cells, Tissues, and Cellular and Tissue-Based Products (HCT/Ps)'' dated... Tissue Practice (CGTP) and Additional Requirements for Manufacturers of Human Cells, Tissues, and...

  10. Advanced Thermoplastic Polymers and Additive Manufacturing Applied to ISS Columbus Toolbox: Lessons Learnt and Results

    NASA Astrophysics Data System (ADS)

    Ferrino, Marinella; Secondo, Ottaviano; Sabbagh, Amir; Della Sala, Emilio

    2014-06-01

    In the frame of the International Space Station (ISS) Exploitation Program a new toolbox has been realized by TAS-I to accommodate the tools currently in use on the ISS Columbus Module utilizing full-scale prototypes obtained with 3D rapid prototyping. The manufacturing of the flight hardware by means of advanced thermoplastic polymer UL TEM 9085 and additive manufacturing Fused Deposition Modelling (FDM) technology represent innovative elements. In this paper, the results achieved and the lessons learned are analyzed to promote future technology know-how. The acquired experience confirmed that the additive manufacturing process allows to save time/cost and to realize new shapes/features to introduce innovation in products and future design processes for space applications.

  11. In situ X-ray imaging of defect and molten pool dynamics in laser additive manufacturing.

    PubMed

    Leung, Chu Lun Alex; Marussi, Sebastian; Atwood, Robert C; Towrie, Michael; Withers, Philip J; Lee, Peter D

    2018-04-10

    The laser-matter interaction and solidification phenomena associated with laser additive manufacturing (LAM) remain unclear, slowing its process development and optimisation. Here, through in situ and operando high-speed synchrotron X-ray imaging, we reveal the underlying physical phenomena during the deposition of the first and second layer melt tracks. We show that the laser-induced gas/vapour jet promotes the formation of melt tracks and denuded zones via spattering (at a velocity of 1 m s -1 ). We also uncover mechanisms of pore migration by Marangoni-driven flow (recirculating at a velocity of 0.4 m s -1 ), pore dissolution and dispersion by laser re-melting. We develop a mechanism map for predicting the evolution of melt features, changes in melt track morphology from a continuous hemi-cylindrical track to disconnected beads with decreasing linear energy density and improved molten pool wetting with increasing laser power. Our results clarify aspects of the physics behind LAM, which are critical for its development.

  12. Influence of scan strategy and molten pool configuration on microstructures and tensile properties of selective laser melting additive manufactured aluminum based parts

    NASA Astrophysics Data System (ADS)

    Dai, Donghua; Gu, Dongdong; Zhang, Han; Xiong, Jiapeng; Ma, Chenglong; Hong, Chen; Poprawe, Reinhart

    2018-02-01

    Selective laser melting additive manufacturing of the AlSi12 material parts through the re-melting of the previously solidified layer using the continuous two layers 90° rotate scan strategy was conducted. The influence of the re-melting behavior and scan strategy on the formation of the ;track-track; and ;layer-layer; molten pool boundaries (MPBs), dimensional accuracy, microstructure feature, tensile properties, microscopic sliding behavior and the fracture mechanism as loaded a tensile force has been studied. It showed that the defects, such as the part distortion, delamination and cracks, were significantly eliminated with the deformation rate less than 1%. The microstructure of a homogeneous distribution of the Si phase, no apparent grain orientation on both sides of the MPBs, was produced in the as-fabricated part, promoting the efficient transition of the load stress. Cracks preferentially initiate at the ;track-track; MPBs when the tensile stress increases to a certain value, resulting in the formation of the cleavage steps along the tensile loading direction. The cracks propagate along the ;layer-layer; MPBs, generating the fine dimples. The mechanical behavior of the SLM-processed AlSi12 parts can be significantly enhanced with the ultimate tensile strength, yield strength and elongation of 476.3 MPa, 315.5 MPa and 6.7%, respectively.

  13. Additive Biomanufacturing: An Advanced Approach for Periodontal Tissue Regeneration.

    PubMed

    Carter, Sarah-Sophia D; Costa, Pedro F; Vaquette, Cedryck; Ivanovski, Saso; Hutmacher, Dietmar W; Malda, Jos

    2017-01-01

    Periodontitis is defined as a chronic inflammatory condition, characterized by destruction of the periodontium, composed of hard (i.e. alveolar bone and cementum) and soft tissues (i.e. gingiva and periodontal ligament) surrounding and supporting the teeth. In severe cases, reduced periodontal support can lead to tooth loss, which requires tissue augmentation or procedures that initiate a repair, yet ideally a regenerative response. However, mimicking the three-dimensional complexity and functional integration of the different tissue components via scaffold- and/or matrix-based guided tissue engineering represents a great challenge. Additive biomanufacturing, a manufacturing method in which objects are designed and fabricated in a layer-by-layer manner, has allowed a paradigm shift in the current manufacturing of medical devices and implants. This shift from design-to-manufacture to manufacture-to-design, seen from a translational research point of view, provides the biomedical engineering and periodontology communities a technology with the potential to achieve tissue regeneration instead of repair. In this review, the focus is put on additively biomanufactured scaffolds for periodontal applications. Besides a general overview of the concept of additive biomanufacturing within this field, different developed scaffold designs are described. To conclude, future directions regarding advanced biomaterials and additive biomanufacturing technologies for applications in regenerative periodontology are highlighted.

  14. Big Area Additive Manufacturing of High Performance Bonded NdFeB Magnets

    PubMed Central

    Li, Ling; Tirado, Angelica; Nlebedim, I. C.; Rios, Orlando; Post, Brian; Kunc, Vlastimil; Lowden, R. R.; Lara-Curzio, Edgar; Fredette, Robert; Ormerod, John; Lograsso, Thomas A.; Paranthaman, M. Parans

    2016-01-01

    Additive manufacturing allows for the production of complex parts with minimum material waste, offering an effective technique for fabricating permanent magnets which frequently involve critical rare earth elements. In this report, we demonstrate a novel method - Big Area Additive Manufacturing (BAAM) - to fabricate isotropic near-net-shape NdFeB bonded magnets with magnetic and mechanical properties comparable or better than those of traditional injection molded magnets. The starting polymer magnet composite pellets consist of 65 vol% isotropic NdFeB powder and 35 vol% polyamide (Nylon-12). The density of the final BAAM magnet product reached 4.8 g/cm3, and the room temperature magnetic properties are: intrinsic coercivity Hci = 688.4 kA/m, remanence Br = 0.51 T, and energy product (BH)max = 43.49 kJ/m3 (5.47 MGOe). In addition, tensile tests performed on four dog-bone shaped specimens yielded an average ultimate tensile strength of 6.60 MPa and an average failure strain of 4.18%. Scanning electron microscopy images of the fracture surfaces indicate that the failure is primarily related to the debonding of the magnetic particles from the polymer binder. The present method significantly simplifies manufacturing of near-net-shape bonded magnets, enables efficient use of rare earth elements thus contributing towards enriching the supply of critical materials. PMID:27796339

  15. Big Area Additive Manufacturing of High Performance Bonded NdFeB Magnets.

    PubMed

    Li, Ling; Tirado, Angelica; Nlebedim, I C; Rios, Orlando; Post, Brian; Kunc, Vlastimil; Lowden, R R; Lara-Curzio, Edgar; Fredette, Robert; Ormerod, John; Lograsso, Thomas A; Paranthaman, M Parans

    2016-10-31

    Additive manufacturing allows for the production of complex parts with minimum material waste, offering an effective technique for fabricating permanent magnets which frequently involve critical rare earth elements. In this report, we demonstrate a novel method - Big Area Additive Manufacturing (BAAM) - to fabricate isotropic near-net-shape NdFeB bonded magnets with magnetic and mechanical properties comparable or better than those of traditional injection molded magnets. The starting polymer magnet composite pellets consist of 65 vol% isotropic NdFeB powder and 35 vol% polyamide (Nylon-12). The density of the final BAAM magnet product reached 4.8 g/cm 3 , and the room temperature magnetic properties are: intrinsic coercivity H ci  = 688.4 kA/m, remanence B r  = 0.51 T, and energy product (BH) max  = 43.49 kJ/m 3 (5.47 MGOe). In addition, tensile tests performed on four dog-bone shaped specimens yielded an average ultimate tensile strength of 6.60 MPa and an average failure strain of 4.18%. Scanning electron microscopy images of the fracture surfaces indicate that the failure is primarily related to the debonding of the magnetic particles from the polymer binder. The present method significantly simplifies manufacturing of near-net-shape bonded magnets, enables efficient use of rare earth elements thus contributing towards enriching the supply of critical materials.

  16. Geometrical accuracy of metallic objects produced with additive or subtractive manufacturing: A comparative in vitro study.

    PubMed

    Braian, Michael; Jönsson, David; Kevci, Mir; Wennerberg, Ann

    2018-07-01

    To evaluate the accuracy and precision of objects produced by additive manufacturing systems (AM) for use in dentistry and to compare with subtractive manufacturing systems (SM). Ten specimens of two geometrical objects were produced by five different AM machines and one SM machine. Object A mimics an inlay-shaped object, while object B imitates a four-unit bridge model. All the objects were sorted into different measurement dimensions (x, y, z), linear distances, angles and corner radius. None of the additive manufacturing or subtractive manufacturing groups presented a perfect match to the CAD file with regard to all parameters included in the present study. Considering linear measurements, the precision for subtractive manufacturing group was consistent in all axes for object A, presenting results of <0.050mm. The additive manufacturing groups had consistent precision in the x-axis and y-axis but not in the z-axis. With regard to corner radius measurements, the SM group had the best overall accuracy and precision for both objects A and B when compared to the AM groups. Within the limitations of this in vitro study, the conclusion can be made that subtractive manufacturing presented overall precision on all measurements below 0.050mm. The AM machines also presented fairly good precision, <0.150mm, on all axes except for the z-axis. Knowledge regarding accuracy and precision for different production techniques utilized in dentistry is of great clinical importance. The dental community has moved from casting to milling and additive techniques are now being implemented. Thus all these production techniques need to be tested, compared and validated. Copyright © 2018 The Academy of Dental Materials. Published by Elsevier Inc. All rights reserved.

  17. Development and fabrication of patient-specific knee implant using additive manufacturing techniques

    NASA Astrophysics Data System (ADS)

    Zammit, Robert; Rochman, Arif

    2017-10-01

    Total knee replacement is the most effective treatment to relief pain and restore normal function in a diseased knee joint. The aim of this research was to develop a patient-specific knee implant which can be fabricated using additive manufacturing techniques and has reduced wear rates using a highly wear resistant materials. The proposed design was chosen based on implant requirements, such as reduction in wear rates as well as strong fixation. The patient-specific knee implant improves on conventional knee implants by modifying the articulating surfaces and bone-implant interfaces. Moreover, tribological tests of different polymeric wear couples were carried out to determine the optimal materials to use for the articulating surfaces. Finite element analysis was utilized to evaluate the stresses sustained by the proposed design. Finally, the patient-specific knee implant was successfully built using additive manufacturing techniques.

  18. Wood lens design philosophy based on a binary additive manufacturing technique

    NASA Astrophysics Data System (ADS)

    Marasco, Peter L.; Bailey, Christopher

    2016-04-01

    Using additive manufacturing techniques in optical engineering to construct a gradient index (GRIN) optic may overcome a number of limitations of GRIN technology. Such techniques are maturing quickly, yielding additional design degrees of freedom for the engineer. How best to employ these degrees of freedom is not completely clear at this time. This paper describes a preliminary design philosophy, including assumptions, pertaining to a particular printing technique for GRIN optics. It includes an analysis based on simulation and initial component measurement.

  19. A Delphi Study of Additive Manufacturing Applicability for United States Air Force Civil Engineer Contingency Operations

    DTIC Science & Technology

    2015-03-26

    10 Table 2. Additive Manufacturing Categories (ASTM International , 2012) ..................... 14 Table 3. Delphi... flexibility in the design and structure of manufactured parts. It also allows for the creation of thousands of possible parts or tools from a single...machine. These benefits of 3 precision and flexibility in design and manufacturing show promising possibilities for addressing the general nature of

  20. Benchmarking Naval Shipbuilding With 3D Laser Scanning, Additive Manufacturing, and Collaborative Product Lifecycle Management

    DTIC Science & Technology

    2016-04-30

    manufacturing is also commonly referred to as 3D printing . AM differs radically from the currently dominant manufacturing methodologies. Most current...referred to as 3D printing . In the automotive industry, Ford Motor Co. uses 3D printing in several areas, including the tooling used to create production...four months and cost $500,000 to build, while a 3D - printed manifold prototype costs $3,000 to build over four days. Additive Manufacturing in the