Science.gov

Sample records for casting

  1. Casting Technology.

    ERIC Educational Resources Information Center

    Wright, Michael D.; And Others

    1992-01-01

    Three articles discuss (1) casting technology as it relates to industry, with comparisons of shell casting, shell molding, and die casting; (2) evaporative pattern casting for metals; and (3) high technological casting with silicone rubber. (JOW)

  2. Hair casts

    PubMed Central

    Parmar, Sweta S.; Parmar, Kirti S.; Shah, Bela J.

    2014-01-01

    Hair casts or pseudonits are circumferential concretions, which cover the hair shaft in such a way that, it could be easily removed. They are thin, cylindrical, and elongated in length. We present an unusual case of an 8-year-old girl presenting with hair casts. Occurrence of these is unusual, and they may have varied associations. This patient was suffering from developmental delay. It is commonly misdiagnosed as and very important to differentiate from pediculosis capitis. PMID:25396168

  3. Electromagnetic casting

    SciTech Connect

    Evans, J.W.; Kageyama, R.; Deepak; Cook, D.P.; Prasso, D.C.; Nishioka, S.

    1995-12-31

    Electromagnetic casting (EMC) is a technology that is used extensively in the aluminum industry to cast ingots with good surface finish for subsequent rolling into consumer product. The paper reviews briefly some investigations from the eighties wherein models for EMC were developed. Then more recent work is examined wherein more realistic 3D models have been developed, the traditional studies of electromagnetic and magnetohydrodynamic phenomena have been supplemented with research on heat transport, and the stability of the metal free surface has been examined. The paper concludes with three generalizations concerning modeling that may have wider applicability than EMC.

  4. Project CAST.

    ERIC Educational Resources Information Center

    Charles County Board of Education, La Plata, MD. Office of Special Education.

    The document outlines procedures for implementing Project CAST (Community and School Together), a community-based career education program for secondary special education students in Charles County, Maryland. Initial sections discuss the role of a learning coordinator, (including relevant travel reimbursement and mileage forms) and an overview of…

  5. Casting methods

    DOEpatents

    Marsden, Kenneth C.; Meyer, Mitchell K.; Grover, Blair K.; Fielding, Randall S.; Wolfensberger, Billy W.

    2012-12-18

    A casting device includes a covered crucible having a top opening and a bottom orifice, a lid covering the top opening, a stopper rod sealing the bottom orifice, and a reusable mold having at least one chamber, a top end of the chamber being open to and positioned below the bottom orifice and a vacuum tap into the chamber being below the top end of the chamber. A casting method includes charging a crucible with a solid material and covering the crucible, heating the crucible, melting the material, evacuating a chamber of a mold to less than 1 atm absolute through a vacuum tap into the chamber, draining the melted material into the evacuated chamber, solidifying the material in the chamber, and removing the solidified material from the chamber without damaging the chamber.

  6. Casting materials

    DOEpatents

    Chaudhry, Anil R. (Xenia, OH); Dzugan, Robert (Cincinnati, OH); Harrington, Richard M. (Cincinnati, OH); Neece, Faurice D. (Lyndurst, OH); Singh, Nipendra P. (Pepper Pike, OH)

    2011-06-14

    A foam material comprises a liquid polymer and a liquid isocyanate which is mixed to make a solution that is poured, injected or otherwise deposited into a corresponding mold. A reaction from the mixture of the liquid polymer and liquid isocyanate inside the mold forms a thermally collapsible foam structure having a shape that corresponds to the inside surface configuration of the mold and a skin that is continuous and unbroken. Once the reaction is complete, the foam pattern is removed from the mold and may be used as a pattern in any number of conventional casting processes.

  7. Thin Wall Iron Castings

    SciTech Connect

    J.F. Cuttino; D.M. Stefanescu; T.S. Piwonka

    2001-10-31

    Results of an investigation made to develop methods of making iron castings having wall thicknesses as small as 2.5 mm in green sand molds are presented. It was found that thin wall ductile and compacted graphite iron castings can be made and have properties consistent with heavier castings. Green sand molding variables that affect casting dimensions were also identified.

  8. INTERIOR VIEW WITH CASTING MACHINE AND CASTING FOREMAN OBSERVING OPERATION ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR VIEW WITH CASTING MACHINE AND CASTING FOREMAN OBSERVING OPERATION TO ENSURE MAXIMUM PRODUCTION AND QUALITY. - McWane Cast Iron Pipe Company, Pipe Casting Area, 1201 Vanderbilt Road, Birmingham, Jefferson County, AL

  9. Cool Cast Facts

    MedlinePLUS

    ... outer layer is usually made of plaster or fiberglass. Fiberglass casts are made of fiberglass, which is a plastic that can be shaped. Fiberglass casts come in many different colors — if you' ...

  10. LLNL casting technology

    SciTech Connect

    Shapiro, A.B.; Comfort, W.J. III

    1994-01-01

    Competition to produce cast parts of higher quality, lower rejection rate, and lower cost is a fundamental factor in the global economy. To gain an edge on foreign competitors, the US casting industry must cut manufacturing costs and reduce the time from design to market. Casting research and development (R&D) are the key to increasing US compentiveness in the casting arena. Lawrence Livermore National Laboratory (LLNL) is the home of a wide range of R&D projects that push the boundaries of state-of-the art casting. LLNL casting expertise and technology include: casting modeling research and development, including numerical simulation of fluid flow, heat transfer, reaction/solidification kinetics, and part distortion with residual stresses; special facilities to cast toxic material; extensive experience casting metals and nonmetals; advanced measurement and instrumentation systems. Department of Energy (DOE) funding provides the leverage for LLNL to collaborate with industrial partners to share this advanced casting expertise and technology. At the same time, collaboration with industrial partners provides LLNL technologists with broader insights into casting industry issues, casting process data, and the collective, experience of industry experts. Casting R&D is also an excellent example of dual-use technology; it is the cornerstone for increasing US industrial competitiveness and minimizing waste nuclear material in weapon component production. Annual funding for casting projects at LLNL is $10M, which represents 1% of the total LLNL budget. Metal casting accounts for about 80% of the funding. Funding is nearly equally divided between development directed toward US industrial competitiveness and weapon component casting.

  11. LLNL casting technology

    NASA Astrophysics Data System (ADS)

    Shapiro, A. B.; Comfort, W. J., III

    1994-01-01

    Competition to produce cast parts of higher quality, lower rejection rate, and lower cost is a fundamental factor in the global economy. To gain an edge on foreign competitors, the US casting industry must cut manufacturing costs and reduce the time from design to market. Casting research and development (R&D) are the key to increasing US competiveness in the casting arena. Lawrence Livermore National Laboratory (LLNL) is the home of a wide range of R&D projects that push the boundaries of state-of-the art casting. LLNL casting expertise and technology include: casting modeling research and development, including numerical simulation of fluid flow, heat transfer, reaction/solidification kinetics, and part distortion with residual stresses; special facilities to cast toxic material; extensive experience casting metals and nonmetals; advanced measurement and instrumentation systems. Department of Energy (DOE) funding provides the leverage for LLNL to collaborate with industrial partners to share this advanced casting expertise and technology. At the same time, collaboration with industrial partners provides LLNL technologists with broader insights into casting industry issues, casting process data, and the collective experience of industry experts. Casting R&D is also an excellent example of dual-use technology; it is the cornerstone for increasing US industrial competitiveness and minimizing waste nuclear material in weapon component production. Annual funding for casting projects at LLNL is $10M, which represents 1% of the total LLNL budget. Metal casting accounts for about 80% of the funding. Funding is nearly equally divided between development directed toward US industrial competitiveness and weapon component casting.

  12. Improving Metal Casting Process

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Don Sirois, an Auburn University research associate, and Bruce Strom, a mechanical engineering Co-Op Student, are evaluating the dimensional characteristics of an aluminum automobile engine casting. More accurate metal casting processes may reduce the weight of some cast metal products used in automobiles, such as engines. Research in low gravity has taken an important first step toward making metal products used in homes, automobiles, and aircraft less expensive, safer, and more durable. Auburn University and industry are partnering with NASA to develop one of the first accurate computer model predictions of molten metals and molding materials used in a manufacturing process called casting. Ford Motor Company's casting plant in Cleveland, Ohio is using NASA-sponsored computer modeling information to improve the casting process of automobile and light-truck engine blocks.

  13. SLIP CASTING METHOD

    DOEpatents

    Allison, A.G.

    1959-09-01

    S>A process is described for preparing a magnesium oxide slip casting slurry which when used in conjunction with standard casting techniques results in a very strong "green" slip casting and a fired piece of very close dimensional tolerance. The process involves aging an aqueous magnestum oxide slurry, having a basic pH value, until it attains a specified critical viscosity at which time a deflocculating agent is added without upsetting the basic pH value.

  14. Evolution of halictine castes

    NASA Astrophysics Data System (ADS)

    Knerer, Gerd

    1980-03-01

    Social halictine bees have female castes that range from species with no size differences to those with a discrete bimodality. Female caste differences are inversely correlated with the number of males produced in the first brood. It is proposed that the sexual dimorphism of solitary forms is being usurped by the female caste system of species in the process of turning social. Thus, caste differences and summer male suppression are greatest in the social species originating from solitary precursors with distinct sexual dimorphism, and are least in species evolving from solitary ancestors with a continuous sexual polymorphism.

  15. INTERIOR VIEW WITH PIPE CASTING MACHINE CASTING A 24' PIPE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR VIEW WITH PIPE CASTING MACHINE CASTING A 24' PIPE AND OPERATOR JOHNNY NIXON. - United States Pipe & Foundry Company Plant, Pipe Casting & Testing Area, 2023 St. Louis Avenue at I-20/59, Bessemer, Jefferson County, AL

  16. INTERIOR VIEW WITH LARGE PIPE CASTING MACHINE CASTING A 48' ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR VIEW WITH LARGE PIPE CASTING MACHINE CASTING A 48' PIPE. - United States Pipe & Foundry Company Plant, Pipe Casting & Testing Area, 2023 St. Louis Avenue at I-20/59, Bessemer, Jefferson County, AL

  17. INTERIOR VIEW WITH LARGE PIPE CASTING MACHINE CASTING A 48' ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR VIEW WITH LARGE PIPE CASTING MACHINE CASTING A 48' PIPE OPERATOR SPRAYING A POWDER TO HELP SOLIDIFY THE PIPE BEING CENTRIFUGALLY CAST. - United States Pipe & Foundry Company Plant, Pipe Casting & Testing Area, 2023 St. Louis Avenue at I-20/59, Bessemer, Jefferson County, AL

  18. Casting in Sport

    PubMed Central

    DeCarlo, Mark; Malone, Kathy; Darmelio, John; Rettig, Arthur

    1994-01-01

    Attempts by sports medicine professionals to return high school athletes with hand and wrist injuries to competition quickly and safely have been the source of confusion and debate on many playing fields around the country. In addition to the differing views regarding the appropriateness of playing cast usage in high school football, a debate exists among sports medicine professionals as to which material is best suited for playing cast construction. Materials used in playing cast construction should be hard enough to provide sufficient stabilization to the injured area and include adequate padding to absorb blunt impact forces. The purpose of the biomechanical portion of this investigation was to attempt to determine the most appropriate materials for use in constructing playing casts for the hand and wrist by assessing different materials for: 1) hardness using a Shore durometer, and 2) ability to absorb impact using a force platform. Results revealed that RTV11 and Scotchcast were the least hard of the underlying casting materials and that Temper Stick foam greatly increased the ability of RTV11 to absorb impact. Assessment of the mechanical properties of playing cast materials and review of current developments in high school football rules are used to aid practitioners in choosing the most appropriate materials for playing cast construction. ImagesFig 1.Fig 2.Fig 3. PMID:16558257

  19. Clean Metal Casting

    SciTech Connect

    Makhlouf M. Makhlouf; Diran Apelian

    2002-02-05

    The objective of this project is to develop a technology for clean metal processing that is capable of consistently providing a metal cleanliness level that is fit for a given application. The program has five tasks: Development of melt cleanliness assessment technology, development of melt contamination avoidance technology, development of high temperature phase separation technology, establishment of a correlation between the level of melt cleanliness and as cast mechanical properties, and transfer of technology to the industrial sector. Within the context of the first task, WPI has developed a standardized Reduced Pressure Test that has been endorsed by AFS as a recommended practice. In addition, within the context of task1, WPI has developed a melt cleanliness sensor based on the principles of electromagnetic separation. An industrial partner is commercializing the sensor. Within the context of the second task, WPI has developed environmentally friendly fluxes that do not contain fluorine. Within the context of the third task, WPI modeled the process of rotary degassing and verified the model predictions with experimental data. This model may be used to optimize the performance of industrial rotary degassers. Within the context of the fourth task, WPI has correlated the level of melt cleanliness at various foundries, including a sand casting foundry, a permanent mold casting foundry, and a die casting foundry, to the casting process and the resultant mechanical properties. This is useful in tailoring the melt cleansing operations at foundries to the particular casting process and the desired properties of cast components.

  20. Method of casting aerogels

    DOEpatents

    Poco, John F. (Livermore, CA)

    1993-01-01

    The invention describes a method for making monolithic castings of transparent silica aerogel with densities in the range from 0.001 g/cm.sup.3 to 0.6 g/cm.sup.3. Various shapes of aerogels are cast in flexible polymer molds which facilitate removal and eliminate irregular surfaces. Mold dimensions are preselected to account for shrinkage of alcogel which occurs during the drying step of supercritical extraction of solvent.

  1. Method of casting aerogels

    DOEpatents

    Poco, J.F.

    1993-09-07

    The invention describes a method for making monolithic castings of transparent silica aerogel with densities in the range from 0.001 g/cm[sup 3] to 0.6 g/cm[sup 3]. Various shapes of aerogels are cast in flexible polymer molds which facilitate removal and eliminate irregular surfaces. Mold dimensions are preselected to account for shrinkage of aerogel which occurs during the drying step of supercritical extraction of solvent. 2 figures.

  2. Casting Characteristics of Aluminum Die Casting Alloys

    SciTech Connect

    Makhlouf M. Makhlouf; Diran Apelian

    2002-02-05

    The research program investigates the casting characteristics of selected aluminum die casting alloys. Specifically, the alloys' tendencies towards die soldering and sludge formation, and the alloys' fluidity and machinability are evaluated. It was found that: When the Fe and Mn contents of the alloy are low; caution has to be taken against possible die soldering. When the alloy has a high sludge factor, particularly a high level of Fe, measures must be taken to prevent the formation of large hardspots. For this kind of alloy, the Fe content should be kept at its lowest allowable level and the Mn content should be at its highest possible level. If there are problems in die filling, measures other than changing the alloy chemistry need to be considered first. In terms of alloy chemistry, the elements that form high temperature compounds must be kept at their lowest allowable levels. The alloys should not have machining problems when appropriate machining techniques and machining parameters are used.

  3. A Winning Cast

    NASA Technical Reports Server (NTRS)

    2001-01-01

    Howmet Research Corporation was the first to commercialize an innovative cast metal technology developed at Auburn University, Auburn, Alabama. With funding assistance from NASA's Marshall Space Flight Center, Auburn University's Solidification Design Center (a NASA Commercial Space Center), developed accurate nickel-based superalloy data for casting molten metals. Through a contract agreement, Howmet used the data to develop computer model predictions of molten metals and molding materials in cast metal manufacturing. Howmet Metal Mold (HMM), part of Howmet Corporation Specialty Products, of Whitehall, Michigan, utilizes metal molds to manufacture net shape castings in various alloys and amorphous metal (metallic glass). By implementing the thermophysical property data from by Auburn researchers, Howmet employs its newly developed computer model predictions to offer customers high-quality, low-cost, products with significantly improved mechanical properties. Components fabricated with this new process replace components originally made from forgings or billet. Compared with products manufactured through traditional casting methods, Howmet's computer-modeled castings come out on top.

  4. Salvaged castings and methods of salvaging castings with defective cast cooling bumps

    DOEpatents

    Johnson, Robert Alan (Simpsonville, SC); Schaeffer, Jon Conrad (Greenville, SC); Lee, Ching-Pang (Cincinnati, OH); Abuaf, Nesim (Lincoln City, OR); Hasz, Wayne Charles (Pownal, VT)

    2002-01-01

    Castings for gas turbine parts exposed on one side to a high-temperature fluid medium have cast-in bumps on an opposite cooling surface side to enhance heat transfer. Areas on the cooling surface having defectively cast bumps, i.e., missing or partially formed bumps during casting, are coated with a braze alloy and cooling enhancement material to salvage the part.

  5. CAST FLOOR WITH VIEW OF TORPEDO LADLE (BENEATH CAST FLOOR) ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    CAST FLOOR WITH VIEW OF TORPEDO LADLE (BENEATH CAST FLOOR) AND KEEPERS OF THE CAST HOUSE FLOOR, S.L. KIMBROUGH AND DAVID HOLMES. - U.S. Steel, Fairfield Works, Blast Furnace No. 8, North of Valley Road, West of Ensley-Pleasant Grove Road, Fairfield, Jefferson County, AL

  6. Method for casting polyethylene pipe

    NASA Technical Reports Server (NTRS)

    Elam, R. M., Jr.

    1973-01-01

    Short lengths of 7-cm ID polyethylene pipe are cast in a mold which has a core made of room-temperature-vulcanizable (RTV) silicone. Core expands during casting and shrinks on cooling to allow for contraction of the polyethylene.

  7. Sealing micropores in thin castings

    NASA Technical Reports Server (NTRS)

    Mersereau, G. A.; Nitzschke, G. O.; Ochs, H. L.; Sutch, F. S.

    1981-01-01

    Microscopic pores in thin-walled aluminum castings are sealed by impregnation pretreatment. Technique was developed for investment castings used in hermetically sealed chassic for electronic circuitry. Excessively high leakage rates were previously measured in some chassis.

  8. Casting Of Multilayer Ceramic Tapes

    NASA Technical Reports Server (NTRS)

    Collins, Earl R., Jr.

    1991-01-01

    Procedure for casting thin, multilayer ceramic membranes, commonly called tapes, involves centrifugal casting at accelerations of 1,800 to 2,000 times normal gravitational acceleration. Layers of tape cast one at a time on top of any previous layer or layers. Each layer cast from slurry of ground ceramic suspended in mixture of solvents, binders, and other components. Used in capacitors, fuel cells, and electrolytic separation of oxygen from air.

  9. Mix/Cast Contamination Control

    NASA Technical Reports Server (NTRS)

    Wallentine, M.

    2005-01-01

    Presented is a training handbook for Mix/Cast Contamination Control; a part of a series of training courses to qualify access to Mix/Cast facilities. Contents: List Contamination Control Requirements; Identify foreign objects debris (FOD), Control Areas and their guidelines; Describe environmental monitoring; List Contamination Control Initiatives; Describe concern for Controlled Materials; Identify FOD Controlled Areas in Mix/Cast.

  10. Casting and Angling.

    ERIC Educational Resources Information Center

    Little, Mildred J.; Bunting, Camille

    The self-contained packet contains background information, lesson plans, 15 transparency and student handout masters, drills and games, 2 objective examinations, and references for teaching a 15-day unit on casting and angling to junior high and senior high school students, either as part of a regular physical education program or as a club

  11. Extrusion cast explosive

    DOEpatents

    Scribner, Kenneth J. (Livermore, CA)

    1985-01-01

    Improved, multiphase, high performance, high energy, extrusion cast explosive compositions, comprising, a crystalline explosive material; an energetic liquid plasticizer; a urethane prepolymer, comprising a blend of polyvinyl formal, and polycaprolactone; a polyfunctional isocyanate; and a catalyst are disclosed. These new explosive compositions exhibit higher explosive content, a smooth detonation front, excellent stability over long periods of storage, and lower sensitivity to mechanical stimulants.

  12. Casting and Angling.

    ERIC Educational Resources Information Center

    Smith, Julian W.

    As part of a series of books and pamphlets on outdoor education, this manual consists of easy-to-follow instructions for fishing activities dealing with casting and angling. The manual may be used as a part of the regular physical education program in schools and colleges or as a club activity for the accomplished weekend fisherman or the

  13. 14 CFR 25.621 - Casting factors.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... except castings that are pressure tested as parts of hydraulic or other fluid systems and do not support... bearing factor is larger than the applicable casting factor. (c) Critical castings. For each casting whose... occupants, the following apply: (1) Each critical casting must (i) Have a casting factor of not less than...

  14. AMCC casting development, volume 2

    NASA Technical Reports Server (NTRS)

    1995-01-01

    PCC successfully cast and performed nondestructive testing, FPI and x-ray, on seventeen AMCC castings. Destructive testing, lab analysis and chemical milling, was performed on eleven of the castings and the remaining six castings were shipped to NASA or Aerojet. Two of the six castings shipped, lots 015 and 016, were fully processed per blueprint requirements. PCC has fully developed the gating and processing parameters of this part and feels the part could be implemented into production, after four more castings have been completed to ensure the repeatability of the process. The AMCC casting has been a technically challenging part due to its size, configuration, and alloy type. The height and weight of the wax pattern assembly necessitated the development of a hollow gating system to ensure structural integrity of the shell throughout the investment process. The complexity in the jacket area of the casting required the development of an innovative casting technology that PCC has termed 'TGC' or thermal gradient control. This method of setting up thermal gradients in the casting during solidification represents a significant process improvement for PCC and has been successfully implemented on other programs. The alloy, JBK75, is a relatively new alloy in the investment casting arena and required our engineering staff to learn the gating, processing, and dimensional characteristics of the material.

  15. Melting and casting of FeAl-based cast alloy

    SciTech Connect

    Sikka, V.K.; Wilkening, D.; Liebetrau, J.; Mackey, B.

    1998-11-01

    The FeAl-based intermetallic alloys are of great interest because of their low density, low raw material cost, and excellent resistance to high-temperature oxidation, sulfidation, carburization, and molten salts. The applications based on these unique properties of FeAl require methods to melt and cast these alloys into complex-shaped castings and centrifugal cast tubes. This paper addresses the melting-related issues and the effect of chemistry on the microstructure and hardness of castings. It is concluded that the use of the Exo-Melt{trademark} process for melting and the proper selection of the aluminum melt stock can result in porosity-free castings. The FeAl alloys can be melted and cast from the virgin and revert stock. A large variation in carbon content of the alloys is possible before the precipitation of graphite flakes occurs. Titanium is a very potent addition to refine the grain size of castings. A range of complex sand castings and two different sizes of centrifugal cast tubes of the alloy have already been cast.

  16. Extrusion cast explosive

    DOEpatents

    Scribner, K.J.

    1985-01-29

    Improved, multiphase, high performance, high energy, extrusion cast explosive compositions, comprising, a crystalline explosive material; an energetic liquid plasticizer; a urethane prepolymer, comprising a blend of polyvinyl formal, and polycaprolactone; a polyfunctional isocyanate; and a catalyst are disclosed. These new explosive compositions exhibit higher explosive content, a smooth detonation front, excellent stability over long periods of storage, and lower sensitivity to mechanical stimulants. 1 fig.

  17. Extrusion cast explosive

    DOEpatents

    Scribner, K.J.

    1985-11-26

    Disclosed is an improved, multiphase, high performance, high energy, extrusion cast explosive compositions, comprising, a crystalline explosive material; an energetic liquid plasticizer; a urethane prepolymer, comprising a blend of polyvinyl formal, and polycaprolactone; a polyfunctional isocyanate; and a catalyst. These new explosive compositions exhibit higher explosive content, a smooth detonation front, excellent stability over long periods of storage, and lower sensitivity to mechanical stimulants. 1 fig.

  18. Metal casting extended assessments

    SciTech Connect

    Ambs, L.; Kosanovic, D.; Muller, M.; Kasten, D.

    1999-07-01

    In 1997, the Industrial Assessment Center program of the US Department of Energy initiated Extended Assessments as an option for some of their in-plant assessments. Intended for larger, more complex manufacturing facilities, the multi-day Extended Assessment allows the plant assessment team to explore more complex recommendations with the intent of encouraging major process and equipment changes. In this paper the authors describe the results of Extended Assessments at plants in the Metal Casting Industry, one of the DOE Industries of the Future. They visited five plants, two foundries and three die casting plants, with combined annual sales of $134 million and a combined annual production volume of 35,300 tons. The recommendations offered potential savings to each plant of an average $417,000 or 1.5% of average gross sales. A number of generalizations can be observed based on the assessments in the cast metals industry. First is that many of the smaller firms in this industry have been slow to adopt innovative technology. Off the shelf technologies are available that will help these firms reach the 21st Century. The concept of remelt of metal or scrap in the plant is an operation that can be improved. They found approximately two pounds of metal melted for every pound shipped. Finally, many opportunities exist outside of the core plant operations to reduce operating costs.

  19. High density tape casting system

    NASA Technical Reports Server (NTRS)

    Collins, Earl R., Jr. (inventor)

    1989-01-01

    A system is provided for casting thin sheets (or tapes) of particles bound together, that are used for oxygen membranes and other applications, which enables the particles to be cast at a high packing density in a tape of uniform thickness. A slurry contains the particles, a binder, and a solvent, and is cast against the inside walls of a rotating chamber. Prior to spraying the slurry against the chamber walls, a solvent is applied to a container. The solvent evaporates to saturate the chamber with solvent vapor. Only then is the slurry cast. As a result, the slurry remains fluid long enough to spread evenly over the casting surface formed by the chamber, and for the slurry particles to become densely packed. Only then is the chamber vented to remove solvent, so the slurry can dry. The major novel feature is applying solvent vapor to a rotating chamber before casting slurry against the chamber walls.

  20. LOST FOAM CASTING OF MAGNESIUM ALLOYS

    SciTech Connect

    Han, Qingyou; Dinwiddie, Ralph Barton; Sklad, Philip S; Currie, Kenneth; Abdelrahman, Mohamed; Vondra, Fred; Walford, Graham; Nolan, Dennis J

    2007-01-01

    The lost foam casting process has been successfully used for making aluminum and cast iron thin walled castings of complex geometries. Little work has been carried out on cast magnesium alloys using the lost foam process. The article describes the research activities at Oak Ridge National Laboratory and Tennessee Technological University on lost foam casting of magnesium alloys. The work was focused on castings of simple geometries such as plate castings and window castings. The plate castings were designed to investigate the mold filling characteristics of magnesium and aluminum alloys using an infrared camera. The pate castings were then characterized for porosity distribution. The window castings were made to test the castability of the alloys under lost foam conditions. Significant differences between lost foam aluminum casting and lost foam magnesium casting have been observed.

  1. Cast dielectric composite linear accelerator

    DOEpatents

    Sanders, David M.; Sampayan, Stephen; Slenes, Kirk; Stoller, H. M.

    2009-11-10

    A linear accelerator having cast dielectric composite layers integrally formed with conductor electrodes in a solventless fabrication process, with the cast dielectric composite preferably having a nanoparticle filler in an organic polymer such as a thermosetting resin. By incorporating this cast dielectric composite the dielectric constant of critical insulating layers of the transmission lines of the accelerator are increased while simultaneously maintaining high dielectric strengths for the accelerator.

  2. Fiber-Reinforced Slip Castings

    NASA Technical Reports Server (NTRS)

    Blome, J. C.; Drennan, D. N.; Keeser, H. M.

    1982-01-01

    Addition of silica fibers greatly reduces shrinkage and cracking during casting of ceramics. Fiber-reinforced slip-cast silica ceramics are also tougher and have lower dielectric loss. Silica fibers are hyperpure material containing only 1 part per million total metal-ion impurities. Hyperpure fibers ensure high reflectance and allow casting to be fired at temperature greater than 2,200 degrees F without loss of strength from devitrification.

  3. 21 CFR 888.5940 - Cast component.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... the cast heel, toe cap, cast support, and walking iron. (b) Classification. Class I (general controls... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cast component. 888.5940 Section 888.5940 Food and... ORTHOPEDIC DEVICES Surgical Devices 888.5940 Cast component. (a) Identification. A cast component is...

  4. Replacing London's cast iron mains

    SciTech Connect

    Thorne, A. ); Mathews, P. )

    1992-07-01

    This paper discusses the cast iron gas distribution systems that exist in many cities and contains considerable amounts of pipe that vary in age from 20 to 150 years. In many ways, cast iron is an excellent material. It is inherently corrosion resistant, easy to install and cheap. However, it is also brittle and smaller diameter cast iron pipe has a relatively low beam strength. This can lead, under some circumstances, to failure without external warning, with typically a full-circumferential failure. In congested areas this can lead to serious consequences. As a result, cast iron replacement programs are a common feature in such urban gas distribution systems.

  5. When Your Child Needs a Cast

    MedlinePLUS

    ... hard bandage that's usually made of material like fiberglass or plaster. Casts keep bones in place while ... water. Plaster of Paris casts are heavier than fiberglass casts and don't hold up as well ...

  6. Biotransformation and ToxCast

    EPA Science Inventory

    A major focus in toxicology research is the development of in vitro methods to predict in vivo chemical toxicity. Within the EPA ToxCast program, a broad range of in vitro biochemical and cellular assays have been deployed to profile the biological activity of 320 ToxCast Phase I...

  7. Lost-Soap Aluminum Casting.

    ERIC Educational Resources Information Center

    Mihalow, Paula

    1980-01-01

    Lost-wax casting in sterling silver is a costly experience for the average high school student. However, this jewelry process can be learned at no cost if scrap aluminum is used instead of silver, and soap bars are used instead of wax. This lost-soap aluminum casting process is described. (Author/KC)

  8. Casting Freedom, 1860-1862

    ERIC Educational Resources Information Center

    Social Education, 2005

    2005-01-01

    Thomas Crawford, an American Sculptor, created the full-size figure of Freedom in clay. Molds were made, from which a full-size positive plaster model was cast in five main sections. This model is on view today in the basement rotunda of the Russell Senate Office Building. Clark Mills was a self-taught American sculptor with experience in casting

  9. An evaluation of fiberglass cast application techniques.

    PubMed

    Wilson, D G; Vanderby, R

    1995-01-01

    Cylindrical casts constructed from 2, 3, 4, and 5 inch widths of fiberglass casting material were evaluated for strength in bending using an unstable fracture model. Five-inch casting material produced the strongest casts. The effect of longitudinal splinting with 2-inch fiberglass tape was evaluated in cylindrical casts constructed from 4-inch tape. Casts with splints on the compression side or with splints on both the tension and compression sides were stronger in bending than casts with a single splint on the tension side or casts without splints. PMID:7778250

  10. Sixty Years of Casting Research

    NASA Astrophysics Data System (ADS)

    Campbell, John

    2015-11-01

    The 60 years of solidification research since the publication of Chalmer's constitutional undercooling in 1953 has been a dramatic advance of understanding which has and continues to be an inspiration. In contrast, 60 years of casting research has seen mixed fortunes. One of its success stories relates to improvements in inoculation of gray irons, and another to the discovery of spheroidal graphite iron, although both of these can be classified as metallurgical rather than casting advances. It is suggested that true casting advances have dated from the author's lab in 1992 when a critical surface turbulence condition was defined for the first time. These last 20 years have seen the surface entrainment issues of castings developed to a sufficient sophistication to revolutionize the performance of light alloy and steel foundries. However, there is still a long way to go, with large sections of the steel and Ni-base casting industries still in denial that casting defects are important or even exist. The result has been that special ingots are still cast poorly, and shaped casting operations have suffered massive losses. For secondary melted and cast materials, electro-slag remelting has the potential to be much superior to expensive vacuum arc remelting, which has cost our aerospace and defense industries dearly over the years. This failure to address and upgrade our processing of liquid metals is a serious concern, since the principle entrainment defect, the bifilm, is seen as the principle initiator of cracks in metals; in general, bifilms are the Griffith cracks that initiate failures by cracking. A new generation of crack resistant metals and engineering structures can now be envisaged.

  11. Strip casting with fluxing agent applied to casting roll

    DOEpatents

    Williams, R.S.; O`Malley, R.J.; Sussman, R.C.

    1997-07-29

    A strip caster for producing a continuous strip includes a tundish for containing a melt, a pair of horizontally disposed water cooled casting rolls and devices for electrostatically coating the outer peripheral chill surfaces of the casting rolls with a powder flux material. The casting rolls are juxtaposed relative to one another for forming a pouting basin for receiving the melt through a teeming tube thereby establishing a meniscus between the rolls for forming the strip. The melt is protected from the outside air by a non-oxidizing gas passed through a supply line to a sealing chamber. A preferred flux is boron oxide having a melting point of about 550 C. The flux coating enhances wetting of the steel melt to the casting roll and dissolves any metal oxide formed on the roll. 3 figs.

  12. Strip casting with fluxing agent applied to casting roll

    DOEpatents

    Williams, Robert S. (Fairfield, OH); O'Malley, Ronald J. (Miamisburg, OH); Sussman, Richard C. (West Chester, OH)

    1997-01-01

    A strip caster (10) for producing a continuous strip (24) includes a tundish (12) for containing a melt (14), a pair of horizontally disposed water cooled casting rolls (22) and devices (29) for electrostatically coating the outer peripheral chill surfaces (44) of the casting rolls with a powder flux material (56). The casting rolls are juxtaposed relative to one another for forming a pouting basin (18) for receiving the melt through a teeming tube (16) thereby establishing a meniscus (20) between the rolls for forming the strip. The melt is protected from the outside air by a non-oxidizing gas passed through a supply line (28) to a sealing chamber (26). A preferred flux is boron oxide having a melting point of about 550.degree. C. The flux coating enhances wetting of the steel melt to the casting roll and dissolves any metal oxide formed on the roll.

  13. Strip casting apparatus and method

    DOEpatents

    Williams, Robert S. (Plum, PA); Baker, Donald F. (Hempfield, PA)

    1988-01-01

    Strip casting apparatus including a molten-metal-holding container and a nozzle to deposit molten metal onto a moving chill drum to directly cast continuous metallic strip. The nozzle body includes a slot bounded between a back and a front lip. The slot width exceeds about 20 times the gap distance between the nozzle and the chill drum surface. Preferably, the slot width exceeds 0.5 inch. This method of strip casting minimizes pressure drop, insuring better metal-to-chill-drum contact which promotes heat transfer and results in a better quality metallic strip.

  14. Biomimetic Materials by Freeze Casting

    NASA Astrophysics Data System (ADS)

    Porter, Michael M.; Mckittrick, Joanna; Meyers, Marc A.

    2013-06-01

    Natural materials, such as bone and abalone nacre, exhibit exceptional mechanical properties, a product of their intricate microstructural organization. Freeze casting is a relatively simple, inexpensive, and adaptable materials processing method to form porous ceramic scaffolds with controllable microstructural features. After infiltration of a second polymeric phase, hybrid ceramic-polymer composites can be fabricated that closely resemble the architecture and mechanical performance of natural bone and nacre. Inspired by the narwhal tusk, magnetic fields applied during freeze casting can be used to further control architectural alignment, resulting in freeze-cast materials with enhanced mechanical properties.

  15. Pressure Rig for Repetitive Casting

    NASA Technical Reports Server (NTRS)

    Vasquez, P.; Hutto, W. R.

    1986-01-01

    Equipment life increased by improved insulation. New design cuts time of preparation for casting from several days to about 1 hour. Savings due to elimination of lengthy heating and drying operations associated with preparation of ceramic mold. Quality of casting improved because moisture in cavity eliminated by use of insulating material, and more uniform pressure applied to process. Commercial blanket insulator protects components from heat, increasing life of pressure rig and enabling repeated use. Improved heat protection allows casting of brass and other alloys with higher melting temperatures in pressure rig.

  16. Slip-Cast Superconductive Parts

    NASA Technical Reports Server (NTRS)

    Wise, Stephanie A.; Buckley, John D.; Vasquez, Peter; Buck, Gregory M.; Hicks, Lana P.; Hooker, Matthew W.; Taylor, Theodore D.

    1993-01-01

    Complex shapes fabricated without machining. Nonaqueous slip-casting technique used to form complexly shaped parts from high-temperature superconductive materials like YBa(2)Cu(3)O(7-delta). Such parts useful in motors, vibration dampers, and bearings. In process, organic solvent used as liquid medium. Ceramic molds made by lost-wax process used instead of plaster-of-paris molds, used in aqueous slip-casting but impervious to organic solvents and cannot drain away liquid medium. Organic-solvent-based castings do not stick to ceramic molds as they do to plaster molds.

  17. 21 CFR 880.6185 - Cast cover.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Cast cover. 880.6185 Section 880.6185 Food and....6185 Cast cover. (a) Identification. A cast cover is a device intended for medical purposes that is made of waterproof material and placed over a cast to protect it from getting wet during a shower or...

  18. 21 CFR 880.6185 - Cast cover.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Cast cover. 880.6185 Section 880.6185 Food and....6185 Cast cover. (a) Identification. A cast cover is a device intended for medical purposes that is made of waterproof material and placed over a cast to protect it from getting wet during a shower or...

  19. 21 CFR 888.5940 - Cast component.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Cast component. 888.5940 Section 888.5940 Food and... ORTHOPEDIC DEVICES Surgical Devices 888.5940 Cast component. (a) Identification. A cast component is a device intended for medical purposes to protect or support a cast. This generic type of device...

  20. 21 CFR 888.5940 - Cast component.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Cast component. 888.5940 Section 888.5940 Food and... ORTHOPEDIC DEVICES Surgical Devices 888.5940 Cast component. (a) Identification. A cast component is a device intended for medical purposes to protect or support a cast. This generic type of device...

  1. 21 CFR 880.6185 - Cast cover.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cast cover. 880.6185 Section 880.6185 Food and....6185 Cast cover. (a) Identification. A cast cover is a device intended for medical purposes that is made of waterproof material and placed over a cast to protect it from getting wet during a shower or...

  2. 21 CFR 880.6185 - Cast cover.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Cast cover. 880.6185 Section 880.6185 Food and....6185 Cast cover. (a) Identification. A cast cover is a device intended for medical purposes that is made of waterproof material and placed over a cast to protect it from getting wet during a shower or...

  3. 21 CFR 888.5940 - Cast component.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Cast component. 888.5940 Section 888.5940 Food and... ORTHOPEDIC DEVICES Surgical Devices 888.5940 Cast component. (a) Identification. A cast component is a device intended for medical purposes to protect or support a cast. This generic type of device...

  4. 21 CFR 888.5940 - Cast component.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Cast component. 888.5940 Section 888.5940 Food and... ORTHOPEDIC DEVICES Surgical Devices 888.5940 Cast component. (a) Identification. A cast component is a device intended for medical purposes to protect or support a cast. This generic type of device...

  5. 14 CFR 23.621 - Casting factors.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... part whose bearing factor is larger than the applicable casting factor. (c) Critical castings. For each... casting factor of not less than 1.25 and receive 100 percent inspection by visual, radiographic, and... (ii) Have a casting factor of not less than 2.0 and receive 100 percent visual inspection and...

  6. 14 CFR 23.621 - Casting factors.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... part whose bearing factor is larger than the applicable casting factor. (c) Critical castings. For each... casting factor of not less than 1.25 and receive 100 percent inspection by visual, radiographic, and... (ii) Have a casting factor of not less than 2.0 and receive 100 percent visual inspection and...

  7. 14 CFR 23.621 - Casting factors.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... part whose bearing factor is larger than the applicable casting factor. (c) Critical castings. For each... casting factor of not less than 1.25 and receive 100 percent inspection by visual, radiographic, and... (ii) Have a casting factor of not less than 2.0 and receive 100 percent visual inspection and...

  8. 14 CFR 23.621 - Casting factors.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... part whose bearing factor is larger than the applicable casting factor. (c) Critical castings. For each... casting factor of not less than 1.25 and receive 100 percent inspection by visual, radiographic, and... (ii) Have a casting factor of not less than 2.0 and receive 100 percent visual inspection and...

  9. Clinical experience with a new casting tape.

    PubMed

    Fleming, L L; Miller, K; Sinback, M

    1980-05-01

    Between October 1977 and 1978, 93 CutterCast casts were applied at the Veterans Administration Hospital in Atlanta, Georgia. The composition and application of this new casting system are described, and the performance of the 93 casts is evaluated in relation to ease of application, roentgenographic clarity, skin condition, patient comfort, and ease of removal. The advantages and disadvantages are discussed. PMID:7375970

  10. Investment casting design of experiment. Final report

    SciTech Connect

    Owens, R.

    1997-10-01

    Specific steps in the investment casting process were analyzed in a designed experiment. The casting`s sensitivity to changes in these process steps was experimentally determined Dimensional and radiographic inspection were used to judge the sensitivity of the casting. Thirty-six castings of different pedigrees were poured and measured. Some of the dimensional inspection was conducted during the processing. It was confirmed that wax fixturing, number of gates, gate location, pour and mold temperature, pour speed, and cooling profile all affected the radiographic quality of the casting. Gate and runner assembly techniques, number of gates, and mold temperature affect the dimensional quality of the casting.

  11. Casting Using A Polystyrene Pattern

    NASA Technical Reports Server (NTRS)

    Vasquez, Peter; Guenther, Bengamin; Vranas, Thomas; Veneris, Peter; Joyner, Michael

    1993-01-01

    New technique for making metal aircraft models saves significant amount of time and effort in comparison with conventional lost-wax method. Produces inexpensive, effective wind-tunnel models. Metal wind-tunnel model cast by use of polystyrene pattern.

  12. Moldless casting by laser

    NASA Astrophysics Data System (ADS)

    McLean, Marc A.; Shannon, G. J.; Steen, William M.

    1997-09-01

    The principle of laser cladding involves the use of high power carbon-dioxide lasers and powder deposition technology to provide wear and corrosion resistant surface coatings to engineering components. By injecting metal powder into a laser generated melt pool on a moving substrate a solidified metal track can be produced. Deposition of successive tracks produces a multi-layer build. Laser direct casting (LDC) utilizes a coaxial nozzle enabling consistent omnidirectional deposition to produce 3D components from a selection of metal powders. The influence of the principal process parameters over the process features namely, powder catchment efficiency, beam shape and build rates are presented with several successfully generated 3D components. Nickel, stainless steel and satellite powders were deposited at laser powders of 0.4 to 1.4 kW and speeds of 500 to 1000 mm/min achieving build rates of 3 to 9 mm3/s. Fully dense metallurgical structures have been produced with no cracking or porosity and powder catchment efficiencies up to 85% have been achieved.

  13. Titan Casts Revealing Shadow

    NASA Astrophysics Data System (ADS)

    2004-05-01

    A rare celestial event was captured by NASA's Chandra X-ray Observatory as Titan -- Saturn's largest moon and the only moon in the Solar System with a thick atmosphere -- crossed in front of the X-ray bright Crab Nebula. The X-ray shadow cast by Titan allowed astronomers to make the first X-ray measurement of the extent of its atmosphere. On January 5, 2003, Titan transited the Crab Nebula, the remnant of a supernova explosion that was observed to occur in the year 1054. Although Saturn and Titan pass within a few degrees of the Crab Nebula every 30 years, they rarely pass directly in front of it. "This may have been the first transit of the Crab Nebula by Titan since the birth of the Crab Nebula," said Koji Mori of Pennsylvania State University in University Park, and lead author on an Astrophysical Journal paper describing these results. "The next similar conjunction will take place in the year 2267, so this was truly a once in a lifetime event." Animation of Titan's Shadow on Crab Nebula Animation of Titan's Shadow on Crab Nebula Chandra's observation revealed that the diameter of the X-ray shadow cast by Titan was larger than the diameter of its solid surface. The difference in diameters gives a measurement of about 550 miles (880 kilometers) for the height of the X-ray absorbing region of Titan's atmosphere. The extent of the upper atmosphere is consistent with, or slightly (10-15%) larger, than that implied by Voyager I observations made at radio, infrared, and ultraviolet wavelengths in 1980. "Saturn was about 5% closer to the Sun in 2003, so increased solar heating of Titan may account for some of this atmospheric expansion," said Hiroshi Tsunemi of Osaka University in Japan, one of the coauthors on the paper. The X-ray brightness and extent of the Crab Nebula made it possible to study the tiny X-ray shadow cast by Titan during its transit. By using Chandra to precisely track Titan's position, astronomers were able to measure a shadow one arcsecond in diameter, which corresponds to the size of a dime as viewed from about two and a half miles. Illustration of Crab, Titan's Shadow and Chandra Illustration of Crab, Titan's Shadow and Chandra Unlike almost all of Chandra's images which are made by focusing X-ray emission from cosmic sources, Titan's X-ray shadow image was produced in a manner similar to a medical X-ray. That is, an X-ray source (the Crab Nebula) is used to make a shadow image (Titan and its atmosphere) that is recorded on film (Chandra's ACIS detector). Titan's atmosphere, which is about 95% nitrogen and 5% methane, has a pressure near the surface that is one and a half times the Earth's sea level pressure. Voyager I spacecraft measured the structure of Titan's atmosphere at heights below about 300 miles (500 kilometers), and above 600 miles (1000 kilometers). Until the Chandra observations, however, no measurements existed at heights in the range between 300 and 600 miles. Understanding the extent of Titan's atmosphere is important for the planners of the Cassini-Huygens mission. The Cassini-Huygens spacecraft will reach Saturn in July of this year to begin a four-year tour of Saturn, its rings and its moons. The tour will include close flybys of Titan that will take Cassini as close as 600 miles, and the launching of the Huygens probe that will land on Titan's surface. Chandra's X-ray Shadow of Titan Chandra's X-ray Shadow of Titan "If Titan's atmosphere has really expanded, the trajectory may have to be changed." said Tsunemi. The paper on these results has been accepted and is expected to appear in a June 2004 issue of The Astrophysical Journal. Other members of the research team were Haroyoski Katayama (Osaka University), David Burrows and Gordon Garmine (Penn State University), and Albert Metzger (JPL). Chandra observed Titan from 9:04 to 18:46 UT on January 5, 2003, using its Advanced CCD Imaging Spectrometer instrument. NASA's Marshall Space Flight Center, Huntsville, Ala., manages the Chandra program for the Office of Space Science, NASA Headquarters, Washington. Northrop Grumman of Redondo Beach, Calif., formerly TRW, Inc., was the prime development contractor for the observatory. The Smithsonian Astrophysical Observatory controls science and flight operations from the Chandra X-ray Center in Cambridge, Mass. Additional information and images are available at: http://chandra.harvard.edu and http://chandra.nasa.gov

  14. Fillability of Thin-Wall Steel Castings

    SciTech Connect

    Robert C. Voigt; Joseph Bertoletti; Andrew Kaley; Sandi Ricotta; Travis Sunday

    2002-07-30

    The use of steel components is being challenged by lighter nonferrous or cast iron components. The development of techniques for enhancing and ensuring the filability of thin-wall mold cavities is most critical for thinner wall cast steel production. The purpose of this research was to develop thin-wall casting techniques that can be used to reliably produce thin-wall castings from traditional gravity poured sand casting processes. The focus of the research was to enhance the filling behavior to prevent misrunds. Experiments were conducted to investigate the influence of various foundry variables on the filling of thin section steel castings. These variables include casting design, heat transfer, gating design, and metal fluidity. Wall thickness and pouring temperature have the greatest effect on casting fill. As wall thickness increases the volume to surface area of the casting increases, which increases the solidification time, allowing the metal to flow further in thicker sect ions. Pouring time is another significant variable affecting casting fill. Increases or decreases of 20% in the pouring time were found to have a significant effect on the filling of thin-wall production castings. Gating variables, including venting, pouring head height, and mold tilting also significantly affected thin-wall casting fill. Filters offer less turbulent, steadier flow, which is appropriate for thicker castings, but they do not enhance thin-wall casting fill.

  15. Cast adrift: Gortex cast liners allow greater patient activity.

    PubMed

    Dubowitz, Gerald; Miller, Deborah M

    2003-01-01

    Extremity fractures are a common injury, with nearly 1.5 million cases reported in the United States in 1998. Treatment often involves lengthy periods of immobilization. This report outlines the use of a Gortex cast liner by a subject who was able to engage in swimming and scuba diving during the healing process. We report that a Gortex cast liner may be considered for an active patient who is keen to return to limited activities during fracture healing. Apparently because of a lack of knowledge of their existence, physicians currently are underutilizing this method of casting in active patients. The use of Gortex liners elsewhere has been reported to have higher patient and physician satisfaction in both use and performance, with no reported detrimental effects on outcome. PMID:14518627

  16. Instant Casting Movie Theater: The Future Cast System

    NASA Astrophysics Data System (ADS)

    Maejima, Akinobu; Wemler, Shuhei; Machida, Tamotsu; Takebayashi, Masao; Morishima, Shigeo

    We have developed a visual entertainment system called “Future Cast” which enables anyone to easily participate in a pre-recorded or pre-created film as an instant CG movie star. This system provides audiences with the amazing opportunity to join the cast of a movie in real-time. The Future Cast System can automatically perform all the processes required to make this possible, from capturing participants' facial characteristics to rendering them into the movie. Our system can also be applied to any movie created using the same production process. We conducted our first experimental trial demonstration of the Future Cast System at the Mitsui-Toshiba pavilion at the 2005 World Exposition in Aichi Japan.

  17. Magnesium-lithium casting alloys

    NASA Technical Reports Server (NTRS)

    Latenko, V. P.; Silchenko, T. V.; Tikhonov, V. A.; Maltsev, V. P.; Korablin, V. P.

    1974-01-01

    The strength properties of magnesium-lithium alloys at room, low, and high temperatures are investigated. It is found that the alloys may have practical application at ambient temperatures up to 100 C, that negative temperatures have a favorable influence on the alloy strength, and that cyclic temperature variations have practically no effect on the strength characteristics. The influence of chemical coatings on corrosion resistance of the MgLi alloys is examined. Several facilities based on pressure casting machines, low-pressure casting machines, and magnetodynamic pumps were designed for producing MgLi alloy castings. Results were obtained for MgLi alloys reinforced with fibers having a volumetric content of 15%.

  18. Energy Consumption of Die Casting Operations

    SciTech Connect

    Jerald Brevick; clark Mount-Campbell; Carroll Mobley

    2004-03-15

    Molten metal processing is inherently energy intensive and roughly 25% of the cost of die-cast products can be traced to some form of energy consumption [1]. The obvious major energy requirements are for melting and holding molten alloy in preparation for casting. The proper selection and maintenance of melting and holding equipment are clearly important factors in minimizing energy consumption in die-casting operations [2]. In addition to energy consumption, furnace selection also influences metal loss due to oxidation, metal quality, and maintenance requirements. Other important factors influencing energy consumption in a die-casting facility include geographic location, alloy(s) cast, starting form of alloy (solid or liquid), overall process flow, casting yield, scrap rate, cycle times, number of shifts per day, days of operation per month, type and size of die-casting form of alloy (solid or liquid), overall process flow, casting yield, scrap rate, cycle times, number of shifts per day, days of operation per month, type and size of die-casting machine, related equipment (robots, trim presses), and downstream processing (machining, plating, assembly, etc.). Each of these factors also may influence the casting quality and productivity of a die-casting enterprise. In a die-casting enterprise, decisions regarding these issues are made frequently and are based on a large number of factors. Therefore, it is not surprising that energy consumption can vary significantly from one die-casting enterprise to the next, and within a single enterprise as function of time.

  19. Casting propellant in rocket engine

    NASA Technical Reports Server (NTRS)

    Roach, J. E.; Froehling, S. C. (Inventor)

    1976-01-01

    A method is described for casting a solid propellant in the casing of a rocket engine having a continuous wall with a single opening which is formed by leaves of a material which melt at a temperature of the propellant and with curved edges concentric to the curvature of the spherical casing. The leaves are inserted into the spherical casing through the opening forming a core having a greater width than the width of the single opening and with curved peripheral edges. The cast propellant forms a solid mass and then heated to melt the leaves and provide a central opening with radial projecting flutes.

  20. INTERIOR VIEW WITH CASTING MACHINE COOLING A 20' IRON PIPE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR VIEW WITH CASTING MACHINE COOLING A 20' IRON PIPE PRIOR TO EXTRACTION FROM CASTING MACHINE. - McWane Cast Iron Pipe Company, Pipe Casting Area, 1201 Vanderbilt Road, Birmingham, Jefferson County, AL

  1. INTERIOR VIEW WITH CASTING MACHINE AND A 4" DUCTILE IRON ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR VIEW WITH CASTING MACHINE AND A 4" DUCTILE IRON PIPE BEING EXTRACTED FROM CASTING MACHINE - McWane Cast Iron Pipe Company, Pipe Casting Area, 1201 Vanderbilt Road, Birmingham, Jefferson County, AL

  2. INTERIOR VIEW OF CASTING MACHINE WITH 4' DUCTILE IRON PIPE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR VIEW OF CASTING MACHINE WITH 4' DUCTILE IRON PIPE BEING WEIGHED ON SCALES AT CASTING MACHINE. - McWane Cast Iron Pipe Company, Pipe Casting Area, 1201 Vanderbilt Road, Birmingham, Jefferson County, AL

  3. INTERIOR VIEW, LOOKING NORTH, WITH CASTING SUPERINTENDENT OVERSEEING TRANSFER OF ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR VIEW, LOOKING NORTH, WITH CASTING SUPERINTENDENT OVERSEEING TRANSFER OF MOLTEN METAL TO A CASTING MACHINE. - McWane Cast Iron Pipe Company, Pipe Casting Area, 1201 Vanderbilt Road, Birmingham, Jefferson County, AL

  4. INTERIOR VIEW WITH CASTING MACHINE AND A 4' DUCTILE IRON ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR VIEW WITH CASTING MACHINE AND A 4' DUCTILE IRON PIPE BEING CENTRIFUGALLY CAST, AS OPERATOR WATCHES TO ENSURE QUALITY. - McWane Cast Iron Pipe Company, Pipe Casting Area, 1201 Vanderbilt Road, Birmingham, Jefferson County, AL

  5. When Your Child Needs a Cast

    MedlinePLUS

    ... Questions About Casts Growth Plate Injuries Broken Bones, Sprains, and Strains Broken Bones Going to a Physical Therapist Word! Cast Strains and Sprains Are a Pain The Facts About Broken Bones ...

  6. New fibreglass casting system in orthopaedic practice.

    PubMed

    Davis, B; Dooley, B

    1976-06-26

    The composition, manufacture and application of a new fibreglass casting system for use in orthopaedic practice are described. The performance of the first 51 fibreglass casts used in routine fracture work is reviewed. The advantages (the cast is waterprof, extremely light and strong) and the disadvantages (an ultraviolet light source is required to cure the cast and the fiberglass tape is rather expensive) are evaluated. PMID:979766

  7. 14 CFR 29.621 - Casting factors.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Casting factors. 29.621 Section 29.621... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction General 29.621 Casting factors. (a... approved specifications. Paragraphs (c) and (d) of this section apply to structural castings...

  8. The Ins and Outs of Relief Casting.

    ERIC Educational Resources Information Center

    Greene, Yvonne

    2000-01-01

    Describes a unit on clay casting that introduces students to relief sculpture. The unit takes three 45 to 50 minute class periods three weeks apart. Discusses each class session in detail: (1) creating the casting; (2) turning out and rinsing the casting; and (3) enriching the surface with color. (CMK)

  9. 14 CFR 27.621 - Casting factors.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Casting factors. 27.621 Section 27.621... STANDARDS: NORMAL CATEGORY ROTORCRAFT Design and Construction General 27.621 Casting factors. (a) General... approved specifications. Paragraphs (c) and (d) of this section apply to structural castings...

  10. Prediction of Microporosity in Shrouded Impeller Castings

    SciTech Connect

    Viswanathan, S. Nelson, C.D.

    1998-09-01

    The purpose of this Cooperative Research and Development Agreement (CRADA) between the Oak Ridge National Laboratory (ORNL) and Morris Bean and Company was to link computer models of heat and fluid flow with previously developed quality criteria for the prediction of microporosity in a Al-4.5% Cu alloy shrouded impeller casting. The results may be used to analyze the casting process design for the commercial production of 206 o alloy shrouded impeller castings. Test impeller castings were poured in the laboratory for the purpose of obtaining thermal data and porosity distributions. Also, a simulation of the test impeller casting was conducted and the results validated with porosity measurements on the test castings. A comparison of the predicted and measured microporosity distributions indicated an excellent correlation between experiments and prediction. The results of the experimental and modeling studies undertaken in this project indicate that the quality criteria developed for the prediction of microporosity in Al-4.5% Cu alloy castings can accurately predict regions of elevated microporosity even in complex castings such as the shrouded impeller casting. Accordingly, it should be possible to use quality criteria for porosity prediction in conjunction with computer models of heat and fluid flow to optimize the casting process for the production of shrouded impeller castings. Since high levels of microporosity may be expected to result in poor fatigue properties, casting designs that are optimized for low levels of microporosity should exhibit superior fatigue life.

  11. Tape casting of magnesium oxide.

    SciTech Connect

    Ayala, Alicia; Corral, Erica L.; Loehman, Ronald E.; Bencoe, Denise Nora; Reiterer, Markus; Shah, Raja A.

    2008-02-01

    A tape casting procedure for fabricating ceramic magnesium oxide tapes has been developed as a method to produce flat sheets of sintered MgO that are thin and porous. Thickness of single layer tapes is in the range of 200-400 {micro}m with corresponding surface roughness values in the range of 10-20 {micro}m as measured by laser profilometry. Development of the tape casting technique required optimization of pretreatment for the starting magnesium oxide (MgO) powder as well as a detailed study of the casting slurry preparation and subsequent heat treatments for sintering and final tape flattening. Milling time of the ceramic powder, plasticizer, and binder mixture was identified as a primary factor affecting surface morphology of the tapes. In general, longer milling times resulted in green tapes with a noticeably smoother surface. This work demonstrates that meticulous control of the entire tape casting operation is necessary to obtain high-quality MgO tapes.

  12. Advanced Lost Foam Casting Technology

    SciTech Connect

    Charles E. Bates; Harry E. Littleton; Don Askeland; Taras Molibog; Jason Hopper; Ben Vatankhah

    2000-11-30

    This report describes the research done under the six tasks to improve the process and make it more functional in an industrial environment. Task 1: Pattern Pyrolysis Products and Pattern Properties Task 2: Coating Quality Control Task 3: Fill and Solidification Code Task 4: Alternate Pattern Materials Task 5: Casting Distortion Task 6: Technology Transfer

  13. ENVIRONMENTAL ASSESSMENT OF IRON CASTING

    EPA Science Inventory

    Sampling of ductile iron casting in green sand molds with phenolic isocyanate cores and in phenol-formaldehyde bound shell molds did not provide definitive proof that environmentally hazardous organic emission occur. Both molding systems produced the same type of major emissions,...

  14. Graphite Formation in Cast Iron

    NASA Technical Reports Server (NTRS)

    Stefanescu, D. M.

    1985-01-01

    In the first phase of the project it was proven that by changing the ratio between the thermal gradient and the growth rate for commercial cast iron samples solidifying in a Bridgman type furnace, it is possible to produce all types of graphite structures, from flake to spheroidal, and all types of matrices, from ferritic to white at a certain given level of cerium. KC-135 flight experiments have shown that in a low-gravity environment, no flotation occurs even in spheroidal graphite cast irons with carbon equivalent as high as 5%, while extensive graphite flotation occurred in both flake and spheroidal graphite cast irons, in high carbon samples solidified in a high gravity environment. This opens the way for production of iron-carbon composite materials, with high carbon content (e.g., 10%) in a low gravity environment. By using KC-135 flights, the influence of some basic elements on the solidification of cast iron will be studied. The mechanism of flake to spheroidal graphite transition will be studied, by using quenching experiments at both low and one gravity for different G/R ratios.

  15. Overview of ToxCast

    EPA Science Inventory

    In 2007, EPA launched ToxCast in order to develop a cost-effective approach for prioritizing the toxicity testing of large numbers of chemicals in a short period of time. Using data from state-of-the-art high throughput screening (HTS) bioassays developed in the pharmaceutical i...

  16. The fractography of casting alloys

    SciTech Connect

    Powell, G.W. )

    1994-10-01

    Several types of casting alloys were fractured using various loading modes (uniaxial tension, bending, impact, and torsion, and cyclic stressing), and the corresponding mechanical properties were determined. The unetched and etched fracture surfaces and the microstructures were examined using conventional techniques. The types of casting alloys that were the subjects f these investigations include gray iron, ductile iron, cast steel, and aluminum-base alloys (A380, A356, and 319). The fractographic studies have yielded these generalizations regarding the topography of the fracture surfaces. In the case of low-ductility alloys such as gray iron and the aluminum-base alloys, the tensile edge of a fracture surface produced by a stress system with a strong bending-moment component has a highly irregular contour, whereas the compressive edge of the fracture surface is quite straight and parallel to the bend axis. On the other hand, the periphery of a fracture surface produced by uniaxial tension has a completely irregular contour. The fracture surface produced by cyclic loading of a gray iron does not display any macroscopic evidence (such as a thumb nail) of the loading mode. However, the fracture surface of each of the other casting alloys displays clear, macroscopic evidence of failure induced by fatigue. The aluminum-base alloys fracture completely within the interdendritic region of the microstructure when subjected to monotonic loading by uniaxial tension or bending, whereas a fatigue crack propagates predominantly through the primary crystals of the microstructure.

  17. Casting Freedom, 1860-1862

    ERIC Educational Resources Information Center

    Social Education, 2005

    2005-01-01

    Thomas Crawford, an American Sculptor, created the full-size figure of Freedom in clay. Molds were made, from which a full-size positive plaster model was cast in five main sections. This model is on view today in the basement rotunda of the Russell Senate Office Building. Clark Mills was a self-taught American sculptor with experience in casting…

  18. Math: Objectives Guide. Project CAST.

    ERIC Educational Resources Information Center

    Charles County Board of Education, La Plata, MD. Office of Special Education.

    The guide lists math objectives needed for independent living by secondary special education students. One of a series of Project CAST (Community and School Together) life skills manuals, the guide outlines basic competencies in terms of goal statements, behavioral objectives, and specialized vocabulary for the following areas: money, making

  19. Land-based turbine casting initiative

    SciTech Connect

    Mueller, B.A.; Spicer, R.A.

    1995-12-31

    To meet goals for the ATS program, technical advances developed for aircraft gas turbine engines need to be applied to land-based gas turbines. These advances include directionally solidified and single crystal castings, alloys tailored to exploit these microstructures, complex internal cooling schemes, and coatings. The proposed program to scale aircraft gas turbine casting technology up to land based gas turbine size components is based on low sulfur alloys, casting process development, post-cast process development, and establishing casting defect tolerance levels. The inspection side is also discussed.

  20. Process development of thin strip steel casting

    SciTech Connect

    Sussman, R.C.; Williams, R.S.

    1990-12-01

    An important new frontier is being opened in steel processing with the emergence of thin strip casting. Casting steel directly to thin strip has enormous benefits in energy savings by potentially eliminating the need for hot reduction in a hot strip mill. This has been the driving force for numerous current research efforts into the direct strip casting of steel. The US Department of Energy initiated a program to evaluate the development of thin strip casting in the steel industry. In earlier phases of this program, planar flow casting on an experimental caster was studied by a team of engineers from Westinghouse Electric corporation and Armco Inc. A subsequent research program was designed as a fundamental and developmental study of both planar and melt overflow casting processes. This study was arranged as several separate and distinct tasks which were often completed by different teams of researchers. An early task was to design and build a water model to study fluid flow through different designs of planar flow casting nozzles. Another important task was mathematically modeling of melt overflow casting process. A mathematical solidification model for the formation of the strip in the melt overflow process was written. A study of the material and conditioning of casting substrates was made on the small wheel caster using the melt overflow casting process. This report discusses work on the development of thin steel casting.

  1. Prediction of Part Distortion in Die Casting

    SciTech Connect

    R. Allen Miller

    2005-03-30

    The die casting process is one of the net shape manufacturing techniques and is widely used to produce high production castings with tight tolerances for many industries. An understanding of the stress distribution and the deformation pattern of parts produced by die casting will result in less deviation from the part design specification, a better die design and eventually more productivity and cost savings. This report presents methods that can be used to simulate the die casting process in order to predict the deformation and stresses in the produced part and assesses the degree to which distortion modeling is practical for die casting at the current time. A coupled thermal-mechanical finite elements model was used to simulate the die casting process. The simulation models the effect of thermal and mechanical interaction between the casting and the die. It also includes the temperature dependant material properties of the casting. Based on a designed experiment, a sensitivity analysis was conducted on the model to investigate the effect of key factors. These factors include the casting material model, material properties and thermal interaction between casting and dies. To verify the casting distortion predictions, it was compared against the measured dimensions of produced parts. The comparison included dimensions along and across the parting plane and the flatness of one surface.

  2. Emulsion based cast booster - a priming system

    SciTech Connect

    Gupta, R.N.; Mishra, A.K.

    2005-07-01

    This paper explores the potential of emulsion based cast booster to be used as primer to initiate bulk delivered emulsion explosives used in mines. An attempt has been made for comparative study between conventional cast booster and emulsion based cast booster in terms of the initiation process developed and their capability to develop and maintain the stable detonation process in the column explosives. The study has been conducted using a continuous velocity of detonation (VOD) measuring instrument. During this study three blasts have been monitored. In each blast two holes have been selected for study, the first hole being initiated with conventional cast booster while the other one with emulsion based cast booster. The findings of the study advocates that emulsion based cast booster is capable of efficient priming of bulk delivered column explosive with stable detonation process in the column. Further, the booster had advantages over the conventional PETN/TNT based cast booster. 5 refs., 2 figs., 1 tab., 1 photo.

  3. Search for chameleons with CAST

    NASA Astrophysics Data System (ADS)

    Anastassopoulos, V.; Arik, M.; Aune, S.; Barth, K.; Belov, A.; Bruninger, H.; Cantatore, G.; Carmona, J. M.; Cetin, S. A.; Christensen, F.; Collar, J. I.; Dafni, T.; Davenport, M.; Desch, K.; Dermenev, A.; Eleftheriadis, C.; Fanourakis, G.; Ferrer-Ribas, E.; Friedrich, P.; Galn, J.; Garca, J. A.; Gardikiotis, A.; Garza, J. G.; Gazis, E. N.; Geralis, T.; Giomataris, I.; Hailey, C.; Haug, F.; Hasinoff, M. D.; Hoffmann, D. H. H.; Iguaz, F. J.; Irastorza, I. G.; Jacoby, J.; Jakobsen, A.; Jakov?i?, K.; Kaminski, J.; Karuza, M.; Kavuk, M.; Kr?mar, M.; Krieger, C.; Krger, A.; Laki?, B.; Laurent, J. M.; Liolios, A.; Ljubi?i?, A.; Luzn, G.; Neff, S.; Ortega, I.; Papaevangelou, T.; Pivovaroff, M. J.; Raffelt, G.; Riege, H.; Rosu, M.; Ruz, J.; Savvidis, I.; Solanki, S. K.; Vafeiadis, T.; Villar, J. A.; Vogel, J. K.; Yildiz, S. C.; Zioutas, K.; Brax, P.; Lavrentyev, I.; Upadhye, A.

    2015-10-01

    In this work we present a search for (solar) chameleons with the CERN Axion Solar Telescope (CAST). This novel experimental technique, in the field of dark energy research, exploits both the chameleon coupling to matter (?m) and to photons (??) via the Primakoff effect. By reducing the X-ray detection energy threshold used for axions from 1 keV to 400 eV CAST became sensitive to the converted solar chameleon spectrum which peaks around 600 eV. Even though we have not observed any excess above background, we can provide a 95% C.L. limit for the coupling strength of chameleons to photons of ?? ?1011 for 1

  4. MHD technology in aluminum casting

    SciTech Connect

    Kalinichenko, I.

    1984-08-01

    The use of MHD technology in aluminum casting is discussed. Associates of the Latvian Academy of Sciences Institute of Physics developed magnetohydrodynamic units for the Siberian plant. A MHD unit made it possible to free five persons from heavy work at the plant. Labor productivity doubled in this section. With the aid of the magnetic field, the alloy silumin is obtained in only three hours. Specialists of the Irkutsk affiliate of the All-Union Scientific Research and Design Institute of the Aluminum, Magnesium and Electrode Industry are convinced that MHD technology has a bright future. However, this will necessitate the development of new MHD technology for different types of casting facilities, with their specific features taken into account.

  5. Skin holes of titanium casting.

    PubMed

    Miyakawa, O; Watanabe, K; Okawa, S; Nakano, S; Honma, H; Kobayashi, M; Shiokawa, N

    1993-12-01

    The present study describes refractories which contribute to formation of skin holes of Ti casting. Plates consisting of quartz (Qu) and cristobalite (Cr) powders and Qu- and Cr-MgO mixtures were fired at high temperatures and used as phosphate-free molds. The cross-section of the castings was investigated using an optical microscope and an electron probe microanalyzer. Whereas the castings into the Qu molds were almost complete, those into the Cr molds were incomplete. The surface reaction zone of the Qu molds formed a typical layered structure with fewer skin holes. That of the latter extended deeply into the interior with a net-shaped Ti-Si phase, cracks, and holes. Addition of MgO to Cr effectively improved the castability and changed the reaction zone to the typical layered structure. However, slender holes occurred along the mold wall. The overall area around the holes was contaminated by Si and Mg. Probably, this resulted from a reaction of forsterite with Ti. The reactivity difference between Qu and Cr was not related to the fired strength of mold. PMID:8004911

  6. Cast shadows in wide perspective.

    PubMed

    Pont, Sylvia C; Wijntjes, Maarten W A; Oomes, Augustinus H J; van Doom, Andrea; van Nierop, Onno; de Ridder, Huib; Koenderink, Jan J

    2011-01-01

    We investigated the apparent spatial layout of cast shadows up to very wide fields of view. We presented up to 130 degrees wide images in which two 'flat poles' were standing on a green lawn under a cloudless blue sky on a sunny day. The poles threw sharp cast shadows on the green, of which one was fixed. The observer's task was to adjust the azimuth of the shadow of the other pole such that it fitted the scene. The source elevation was kept constant. The two cast shadows are, of course, parallel in physical space, but generically not in the picture plane because of the wide perspective. We found that observers made huge systematic errors, indicating that, generically, they fail to account for these perspective effects. The systematic deviations could be well described by a weighted linear combination of the directions in the picture plane and in the physical space, with weights that depended on the positions of, and distance between, the poles. PMID:22132508

  7. Tape casting of lanthanum chromite

    SciTech Connect

    Murphy, M.W.; Armstrong, T.R.; Smith, P.A.

    1997-01-01

    Solid oxide fuel cells (SOFCs) are currently being developed for a variety of applications such as stationary on-site power plants and cogeneration. The effects of process additives, ball milling, and solids loading were evaluated for tape casting suspensions of glycine-nitrate-synthesized La{sub 0.7}Ca{sub 0.31}CrO{sub 3} powder. An optimized formulation was obtained based on rheological characterization, electrokinetic sonic amplitude measurements, qualitative examination of green tapes, and the sintered microstructure. The tape casting formulation incorporated 66:34 methyl ethyl ketone/ethyl alcohol solvent, an aliphatic phosphate ester dispersant, and 80 wt% (35 vol%) solids. The best binder/plasticizer system was 12 wt% (15 vol%) poly(isobutyl methacrylate) and 5 wt% (6.3 vol%) benzyl butyl phthalate plasticizer (binder:plasticizer = 2.3). Cast tapes were sintered at 1300 C for 2 h, producing a bulk density of 96.2% theoretical, with linear shrinkage of 22% and an approximate grain size of 1.3 {micro}m.

  8. Method for casting thin metal objects

    SciTech Connect

    Pehrson, Brandon P; Moore, Alan F

    2015-04-14

    Provided herein are various embodiments of systems for casting thin metal plates and sheets. Typical embodiments include layers of mold cavities that are oriented vertically for casting the metal plates. In some embodiments, the mold cavities include a beveled edge such that the plates that are cast have a beveled edge. In some embodiments, the mold cavities are filled with a molten metal through an open horizontal edge of the cavity. In some embodiments, the mold cavities are filled through one or more vertical feed orifices. Further disclosed are methods for forming a thin cast metal plate or sheet where the thickness of the cast part is in a range from 0.005 inches to 0.2 inches, and the surface area of the cast part is in a range from 16 square inches to 144 square inches.

  9. Clean Cast Steel Technology, Phase IV

    SciTech Connect

    Charles E. Bates

    2003-02-24

    The objective of the Clean Cast Steel Technology Program was to improve casting product quality by removing or minimizing oxide defects and to allow the production of higher integrity castings for high speed machining lines. Previous research has concentrated on macro-inclusions that break, chip, or crack machine tool cutters and drills and cause immediate shutdown of the machining lines. The overall goal of the project is to reduce the amount of surface macro-inclusions and improve the machinability of steel castings. Macro-inclusions and improve the machinability of steel castings. Macro-inclusions have been identified by industrial sponsors as a major barrier to improving the quality and marketability of steel castings.

  10. Gating of Permanent Molds for ALuminum Casting

    SciTech Connect

    David Schwam; John F. Wallace; Tom Engle; Qingming Chang

    2004-03-30

    This report summarizes a two-year project, DE-FC07-01ID13983 that concerns the gating of aluminum castings in permanent molds. The main goal of the project is to improve the quality of aluminum castings produced in permanent molds. The approach taken was determine how the vertical type gating systems used for permanent mold castings can be designed to fill the mold cavity with a minimum of damage to the quality of the resulting casting. It is evident that somewhat different systems are preferred for different shapes and sizes of aluminum castings. The main problems caused by improper gating are entrained aluminum oxide films and entrapped gas. The project highlights the characteristic features of gating systems used in permanent mold aluminum foundries and recommends gating procedures designed to avoid common defects. The study also provides direct evidence on the filling pattern and heat flow behavior in permanent mold castings.

  11. Directional Solidification of Nodular Cast Iron

    NASA Technical Reports Server (NTRS)

    Curreri, P. A.; Stefanescu, D. M.; Hendrix, J. C.

    1987-01-01

    Cerium enhances formation of graphite nodules. Preliminary experiments in directional solidification of cast iron shows quantitative correlation of graphite microstructure with growth rate and thermal gradient, with sufficient spheroidizing element to form spheroidal graphite under proper thermal conditions. Experimental approach enables use of directional solidification to study solidification of spheriodal-graphite cast iron in low gravity. Possible to form new structural materials from nodular cast iron.

  12. A Benchmark Study on Casting Residual Stress

    SciTech Connect

    Johnson, Eric M.; Watkins, Thomas R; Schmidlin, Joshua E; Dutler, S. A.

    2012-01-01

    Stringent regulatory requirements, such as Tier IV norms, have pushed the cast iron for automotive applications to its limit. The castings need to be designed with closer tolerances by incorporating hitherto unknowns, such as residual stresses arising due to thermal gradients, phase and microstructural changes during solidification phenomenon. Residual stresses were earlier neglected in the casting designs by incorporating large factors of safety. Experimental measurement of residual stress in a casting through neutron or X-ray diffraction, sectioning or hole drilling, magnetic, electric or photoelastic measurements is very difficult and time consuming exercise. A detailed multi-physics model, incorporating thermo-mechanical and phase transformation phenomenon, provides an attractive alternative to assess the residual stresses generated during casting. However, before relying on the simulation methodology, it is important to rigorously validate the prediction capability by comparing it to experimental measurements. In the present work, a benchmark study was undertaken for casting residual stress measurements through neutron diffraction, which was subsequently used to validate the accuracy of simulation prediction. The stress lattice specimen geometry was designed such that subsequent castings would generate adequate residual stresses during solidification and cooling, without any cracks. The residual stresses in the cast specimen were measured using neutron diffraction. Considering the difficulty in accessing the neutron diffraction facility, these measurements can be considered as benchmark for casting simulation validations. Simulations were performed using the identical specimen geometry and casting conditions for predictions of residual stresses. The simulation predictions were found to agree well with the experimentally measured residual stresses. The experimentally validated model can be subsequently used to predict residual stresses in different cast components. This enables incorporation of the residual stresses at the design phase along with external loads for accurate predictions of fatigue and fracture performance of the cast components.

  13. High-Density-Tape Casting System

    NASA Technical Reports Server (NTRS)

    Collins, Earl R., Jr.

    1987-01-01

    Centrifuge packs solids from slurry into uniform, dense layer. New system produces tapes of nearly theoretical packing density. Centrifugal system used to cast thin tapes for capacitors, fuel cells, and filters. Cylindrical rotary casting chamber mounted on high-speed bearings and connected to motor. Liquid for vapor-pressure control and casting slurry introduced from syringes through rotary seal. During drying step, liquid and vapor vented through feed tubes or other openings. Laminated tapes produced by adding more syringes to cast additional layers of different materials.

  14. Microstructured metal molds fabricated via investment casting

    NASA Astrophysics Data System (ADS)

    Cannon, Andrew H.; King, William P.

    2010-02-01

    This paper describes an investment casting process to produce aluminum molds having integrated microstructures. Unlike conventional micromolding tools, the aluminum mold was large and had complex curved surfaces. The aluminum was cast from curved microstructured ceramic molds which were themselves cast from curved microstructured rubber. The aluminum microstructures had an aspect ratio of 1:1 and sizes ranging from 25 to 50 m. Many structures were successfully cast into the aluminum with excellent replication fidelity, including circular, square and triangular holes. We demonstrate molding of large, curved surfaces having surface microstructures using the aluminum mold.

  15. Spray casting project final report

    SciTech Connect

    Churnetski, S.R.; Thompson, J.E.

    1996-08-01

    Lockheed Martin Energy Systems, Inc. (Energy Systems), along with other participating organizations, has been exploring the feasibility of spray casting depleted uranium (DU) to near-net shape as a waste minimization effort. Although this technology would be useful in a variety of applications where DU was the material of choice, this effort was aimed primarily at gamma-shielding components for use in storage and transportation canisters for high-level radioactive waste, particularly in the Multipurpose Canister (MPC) application. In addition to the waste-minimization benefits, spray casting would simplify the manufacturing process by allowing the shielding components for MPC to be produced as a single component, as opposed to multiple components with many fabrication and assembly steps. In earlier experiments, surrogate materials were used to simulate the properties (specifically reactivity and density) of DU. Based on the positive results from those studies, the project participants decided that further evaluation of the issues and concerns that would accompany spraying DU was warranted. That evaluation occupied substantially all of Fiscal Year 1995, yielding conceptual designs for both an intermediate facility and a production facility and their associated engineering estimates. An intermediate facility was included in this study to allow further technology development in spraying DU. Although spraying DU to near-net shape seems to be feasible, a number of technical, engineering, and safety issues would need to be evaluated before proceeding with a production facility. This report is intended to document the results from the spray-casting project and to provide information needed by anyone interested in proceeding to the next step.

  16. Release of ToxCastDB and ExpoCastDB databases

    EPA Science Inventory

    EPA has released two databases - the Toxicity Forecaster database (ToxCastDB) and a database of chemical exposure studies (ExpoCastDB) - that scientists and the public can use to access chemical toxicity and exposure data. ToxCastDB users can search and download data from over 50...

  17. Control of Cast Iron Microstructure

    NASA Technical Reports Server (NTRS)

    Graham, J.; Lillybeck, N.; Franco, N.; Stefanescu, D. M.

    1985-01-01

    The use of microgravity for industrial research in the processing of cast iron was investigated. Solidification experiments were conducted using the KC-135 and F-104 aircraft, and an experiment plan was developed for follow-on experiments using the Shuttle. Three areas of interest are identified: (1) measurement of thermophysical properties in the melt; (2) understanding of the relative roles of homogeneous nucleation, grain multiplication, and innocultants in forming the microstructure; and (3) exploring the possibility of obtaining an aligned graphite structure in hypereutectic Fe, Ni, and Co.

  18. Yield Improvement in Steel Casting (Yield II)

    SciTech Connect

    Richard A. Hardin; Christoph Beckermann; Tim Hays

    2002-02-18

    This report presents work conducted on the following main projects tasks undertaken in the Yield Improvement in Steel Casting research program: Improvement of Conventional Feeding and Risering Methods, Use of Unconventional Yield Improvement Techniques, and Case Studies in Yield Improvement. Casting trials were conducted and then simulated using the precise casting conditions as recorded by the participating SFSA foundries. These results present a statistically meaningful set of experimental data on soundness versus feeding length. Comparisons between these casting trials and casting trials performed more than forty years ago by Pellini and the SFSA are quite good and appear reasonable. Comparisons between the current SFSA feeding rules and feeding rules based on the minimum Niyama criterion reveal that the Niyama-based rules are generally less conservative. The niyama-based rules also agree better with both the trials presented here, and the casting trails performed by Pellini an d the SFSA years ago. Furthermore, the use of the Niyama criterion to predict centerline shrinkage for horizontally fed plate sections has a theoretical basis according to the casting literature reviewed here. These results strongly support the use of improved feeding rules for horizontal plate sections based on the Niyama criterion, which can be tailored to the casting conditions for a given alloy and to a desired level of soundness. The reliability and repeatability of ASTM shrinkage x-ray ratings was investigated in a statistical study performed on 128 x-rays, each of which were rated seven different times. A manual ''Feeding and Risering Guidelines for Steel Castings' is given in this final report. Results of casting trials performed to test unconventional techniques for improving casting yield are presented. These use a stacked arrangement of castings and riser pressurization to increase the casting yield. Riser pressurization was demonstrated to feed a casting up to four time s the distance of a non-pressurized riser, and can increase casting yield by decreasing the required number of risers. All case studies for this projects were completed and compiled into an SFSA Technical Report that is submitted part of this Final Report

  19. Clean cast steel technology. Final report

    SciTech Connect

    Bates, C.E.; Griffin, J.A.

    1998-06-01

    This report documents the results obtained from the Clean Cast Steel Technology Program financially supported by the DOE Metal Casting Competitiveness Research Program and industry. The primary objective of this program is to develop technology for delivering steel free of oxide macroinclusions to mold cavities. The overall objective is to improve the quality of cast steel by developing and demonstrating the technology for substantially reducing surface and sub-surface oxide inclusions. Two approaches are discussed here. A total of 23 castings were produced by submerge pouring along with sixty conventionally poured castings. The submerged poured castings contained, on average, 96% fewer observable surface inclusions (11.9 vs 0.4) compared to the conventionally poured cast parts. The variation in the population of surface inclusions also decreased by 88% from 5.5 to 0.7. The machinability of the casting was also improved by submerged pouring. The submerge poured castings required fewer cutting tool changes and less operator intervention during machining. Subsequent to these trials, the foundry has decided to purchase more shrouds for continued experimentation on other problem castings where submerge pouring is possible. An examination of melting and pouring practices in four foundries has been carried out. Three of the four foundries showed significant improvement in casting quality by manipulating the melting practice. These melting practice variables can be grouped into two separate categories. The first category is the pouring and filling practice. The second category concerns the concentration of oxidizable elements contained in the steel. Silicon, manganese, and aluminum concentrations were important factors in all four foundries. Clean heats can consistently be produced through improved melting practice and reducing exposure of the steel to atmospheric oxygen during pouring and filling.

  20. DE LAVAUD CASTING FACING NORTH, NOTE CORE MOUNTED IN PREPARATION ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    DE LAVAUD CASTING FACING NORTH, NOTE CORE MOUNTED IN PREPARATION FOR NEXT PIPE CASTING. - United States Pipe & Foundry Company Plant, Pipe Casting & Testing Area, 2023 St. Louis Avenue at I-20/59, Bessemer, Jefferson County, AL

  1. INTERIOR VIEW WITH CASTING MACHINE AND A 20' DUCTILE IRON ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR VIEW WITH CASTING MACHINE AND A 20' DUCTILE IRON PIPE BEING EXTRACTED USING PIPE PULLERS. - McWane Cast Iron Pipe Company, Pipe Casting Area, 1201 Vanderbilt Road, Birmingham, Jefferson County, AL

  2. Energy use in selected metal casting facilities - 2003

    SciTech Connect

    Eppich, Robert E.

    2004-05-01

    This report represents an energy benchmark for various metal casting processes. It describes process flows and energy use by fuel type and processes for selected casting operations. It also provides recommendations for improving energy efficiency in casting.

  3. Casting fine grained, fully dense, strong inorganic materials

    DOEpatents

    Brown, Sam W.; Spencer, Larry S.; Phillips, Michael R.

    2015-11-24

    Methods and apparatuses for casting inorganic materials are provided. The inorganic materials include metals, metal alloys, metal hydrides and other materials. Thermal control zones may be established to control the propagation of a freeze front through the casting. Agitation from a mechanical blade or ultrasonic energy may be used to reduce porosity and shrinkage in the casting. After solidification of the casting, the casting apparatus may be used to anneal the cast part.

  4. 14 CFR 25.621 - Casting factors.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Casting factors. 25.621 Section 25.621... STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction General 25.621 Casting factors. (a... meet approved specifications. Paragraphs (c) and (d) of this section apply to any structural...

  5. 14 CFR 29.621 - Casting factors.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Casting factors. 29.621 Section 29.621 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction General 29.621 Casting factors. (a) General. The factors, tests, and...

  6. 14 CFR 25.621 - Casting factors.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Casting factors. 25.621 Section 25.621 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction General 25.621 Casting factors. (a) General. The factors, tests, and...

  7. 14 CFR 27.621 - Casting factors.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Casting factors. 27.621 Section 27.621 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Design and Construction General 27.621 Casting factors. (a) General. The factors, tests, and...

  8. The CAST (Childhood Asperger Syndrome Test)

    ERIC Educational Resources Information Center

    Williams, Jo; Scott, Fiona; Stott, Carol; Allison, Carrie; Bolton, Patrick; Baron-Cohen, Simon; Brayne, Carol

    2005-01-01

    The Childhood Asperger Syndrome Test (CAST) is a parental questionnaire to screen for autism spectrum conditions. In this validation study, the CAST was distributed to 1925 children aged 5-11 in mainstream Cambridgeshire schools. A sample of participants received a full diagnostic assessment, conducted blind to screen status. The sensitivity of

  9. Materials: unidirectional solidification of cast iron.

    PubMed

    Luyendijk, T; Nieswaag, H; Alsem, W H

    1984-07-13

    The segregation of sulfur in liquid cast iron was studied under conditions of microgravity on Spacelab 1. A rod of cast iron containing carbon, silicon, sulfur, and phosphorus was unidirectionally solidified at four different rates. The influence of sulfur on the graphite structure and the stability of an aluminum oxide skin deposited on the surface of the specimen were investigated. PMID:17837942

  10. Dimensional variability of production steel castings

    SciTech Connect

    Peters, F.E.; Risteu, J.W.; Vaupel, W.G.; DeMeter, E.C.; Voigt, R.C.

    1994-12-31

    Work is ongoing to characterize the dimensional variability of steel casting features. Data are being collected from castings produced at representative Steel Founders` Society of America foundries. Initial results based on more than 12,500 production casting feature measurements are presented for carbon and low alloy steel castings produced in green sand, no-bake, and shell molds. A comprehensive database of casting, pattern, and feature variables has been developed so that the influence of the variables on dimensional variability can be determined. Measurement system analysis is conducted to insure that large measurement error is not reported as dimensional variability. Results indicate that the dimensional variability of production casting features is less than indicated in current US (SFSA) and international (ISO) standards. Feature length, casting weight, parting line and molding process all strongly influence dimensional variability. Corresponding pattern measurements indicate that the actual shrinkage amount for casting features varies considerably. This variation in shrinkage will strongly influence the ability of the foundry to satisfy customer dimensional requirements.

  11. Casting Shadows in the Science Classroom.

    ERIC Educational Resources Information Center

    Nolan, Kathleen

    2003-01-01

    Uses the metaphor of shadows in a critical exploration of what it means to know and how the cultures of classrooms have shaped these images of knowing. Directs attention to objects that cast shadows on the learning and knowing of mathematics and science through the voices of preservice teachers. Discusses shadow casting toward textbooks, teachers,

  12. Processing of IN-718 Lattice Block Castings

    NASA Technical Reports Server (NTRS)

    Hebsur, Mohan G.

    2002-01-01

    Recently a low cost casting method known as lattice block casting has been developed by JAM Corporation, Wilmington, Massachusetts for engineering materials such as aluminum and stainless steels that has shown to provide very high stiffness and strength with only a fraction of density of the alloy. NASA Glenn Research Center has initiated research to investigate lattice block castings of high temperature Ni-base superalloys such as the model system Inconel-718 (IN-718) for lightweight nozzle applications. Although difficulties were encountered throughout the manufacturing process , a successful investment casting procedure was eventually developed. Wax formulation and pattern assembly, shell mold processing, and counter gravity casting techniques were developed. Ten IN-718 lattice block castings (each measuring 15-cm wide by 30-cm long by 1.2-cm thick) have been successfully produced by Hitchiner Gas Turbine Division, Milford, New Hampshire, using their patented counter gravity casting techniques. Details of the processing and resulting microstructures are discussed in this paper. Post casting processing and evaluation of system specific mechanical properties of these specimens are in progress.

  13. Slip casting and nitridation of silicon powder

    NASA Technical Reports Server (NTRS)

    Seiko, Y.

    1985-01-01

    Powdered Silicon was slip-cast with a CaSO4 x 0.5H2O mold and nitrided in a N atm. containing 0 or 5 vol. % H at 1000 to 1420 deg. To remove the castings, the modeling faces were coated successively with an aq. salt soap and powdered cellulose containing Na alginate, and thus prevented the sticking problem.

  14. The CAST (Childhood Asperger Syndrome Test)

    ERIC Educational Resources Information Center

    Williams, Jo; Scott, Fiona; Stott, Carol; Allison, Carrie; Bolton, Patrick; Baron-Cohen, Simon; Brayne, Carol

    2005-01-01

    The Childhood Asperger Syndrome Test (CAST) is a parental questionnaire to screen for autism spectrum conditions. In this validation study, the CAST was distributed to 1925 children aged 5-11 in mainstream Cambridgeshire schools. A sample of participants received a full diagnostic assessment, conducted blind to screen status. The sensitivity of…

  15. Iron/Phosphorus Alloys for Continuous Casting

    NASA Technical Reports Server (NTRS)

    Dufresne, E. R.

    1986-01-01

    Continuous casting becomes practicable because of reduced eutectic temperature. Experimental ferrous alloy has melting point about 350 degrees C lower than conventional steels, making possible to cast structural members and eliminating need for hot rolling. Product has normal metal structure and good physical properties. Process used to make rails, beams, slabs, channels, and pipes.

  16. Synthetic casting tapes: benefits and uses of Delta-Cast Conformable.

    PubMed

    Capper, C

    Casting is a traditional practice that has changed relatively little over thousands of years. Today, however, with the emphasis on evidence-based medicine, health professionals are examining the practice and investigating ways of improving it for the benefit of both patients and those who perform it. Most fractures and many soft tissue injuries are usually managed in a rigid cast, which brings with it complications and disadvantages. The ideal form of fracture fixation would stabilize the fracture while allowing some movement of the fracture site and soft tissue compression. This article explores the use of Delta-Cast Conformable (Johnson and Johnson), a synthetic casting tape, in both primary and secondary casting. The role of Delta-Cast Conformable with regard to focused rigidity casting, a new philosophy in fracture management, is discussed. PMID:9866464

  17. Final report on Expendable Pattern Casting Technology

    SciTech Connect

    Not Available

    1990-07-01

    The Expendable Pattern Casting (EPC) process is a potential casting process breakthrough which could dramatically improve the competitiveness of the US foundry industry. Cooperatively supported by US Industry and the Department of Energy and managed by the American Foundrymen's Society, a project was started in May 1989 to develop and optimize expendable pattern casting technology. Four major tasks were conducted in the first phase of the project. Those tasks involved: (1) reviewing published literature to determine the major problems in the EPC process, (2) evaluating factors influencing sand flow and compaction, (3) evaluating and comparing factors influencing sand flow and compaction, (3) evaluating and comparing casting precision obtained in the EPC process with that obtained in other processes, and (4) identifying critical parameters that control dimensional precision and defect formation in EP castings. 26 refs., 27 figs., 11 tabs.

  18. Possible segregation caused by centrifugal titanium casting.

    PubMed

    Watanabe, K; Okawa, S; Kanatani, M; Nakano, S; Miyakawa, O; Kobayashi, M

    1996-12-01

    The possibility of the segregation under solidification process using a centrifugal casting machine was investigated using an electron probe microanalyzer with elemental distribution map, line analysis and quantitative analysis. When a very small quantity of platinum was added to local molten titanium during the casting process, macroscopic segregation was observed under conditions of density difference of 0.1 g/cm3 at the most, confirming that the centrifugal force of the casting machine is extremely strong. When a Ti-6Al-4V alloy was cast, however, no macroscopic segregation was observed. The centrifugal force of the casting machine examined in the present study hardly results in the body-force segregation in this titanium alloy. PMID:9550020

  19. The production of large structural titanium castings

    NASA Astrophysics Data System (ADS)

    Klepeisz, J.; Veeck, S.

    1997-11-01

    Titanium-alloy castings have recently become an attractive option for critical-structural applications in aerospace structures. These opportunities have occurred primarily because of the development of advanced-process technologies, such as rapid-prototyping methodology and solidification modeling, which have dramatically reduced the cost and time required to obtain first-article castings through concurrent engineering. Moreover, these technologies have lowered the risk involved in examining new applications for titanium castings. This article examines the implementation of these new technologies and the heat treatment and mechanical properties of large structural castings, particularly in relation to section size. Additionally, the production of a cast-titanium transmission adapter for the V-22 Osprey Tiltrotoraircraft is described.

  20. The role of water in slip casting

    NASA Astrophysics Data System (ADS)

    McCauley, R. A.; Phelps, G. W.

    1984-05-01

    Slips and casting are considered in terms of physical and colloidal chemistry. Casting slips are polydisperse suspensions of lyophobic particles in water, whose degree of coagulation is controlled by interaction of flocculating and deflocculating agents. Slip casting rate and viscosity are functions of temperature. Slip rheology and response to deflocculating agents varies significantly as the kinds and amounts of colloid modifiers change. Water is considered as a raw material. Various concepts of water/clay interactions and structures are discussed. Casting is a de-watering operation in which water moves from slip to cast to mold in response to a potential energy termed moisture stress. Drying is an evaporative process from a free water surface.

  1. The role of water in slip casting

    NASA Technical Reports Server (NTRS)

    Mccauley, R. A.; Phelps, G. W.

    1984-01-01

    Slips and casting are considered in terms of physical and colloidal chemistry. Casting slips are polydisperse suspensions of lyophobic particles in water, whose degree of coagulation is controlled by interaction of flocculating and deflocculating agents. Slip casting rate and viscosity are functions of temperature. Slip rheology and response to deflocculating agents varies significantly as the kinds and amounts of colloid modifiers change. Water is considered as a raw material. Various concepts of water/clay interactions and structures are discussed. Casting is a de-watering operation in which water moves from slip to cast to mold in response to a potential energy termed moisture stress. Drying is an evaporative process from a free water surface.

  2. BMM SHAKEOUT AND VIBRATING CONVEYOR TRANSPORT SAND AND CASTINGS TO ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    BMM SHAKEOUT AND VIBRATING CONVEYOR TRANSPORT SAND AND CASTINGS TO SEPARATIONS SCREENS. - Southern Ductile Casting Company, Shaking, Degating & Sand Systems, 2217 Carolina Avenue, Bessemer, Jefferson County, AL

  3. Porosity inside a metal casting

    NASA Technical Reports Server (NTRS)

    2003-01-01

    Pores and voids often form in metal castings on Earth (above) making them useless. A transparent material that behaves at a large scale in microgravity the way that metals behave at the microscopic scale on Earth, will help show how voids form and learn how to prevent them. Scientists are using the microgravity environment on the International Space Station to study how these bubbles form, move and interact. The Pore Formation and Mobility Investigation (PFMI) in the Microgravity Science Glovebox aboard the International Space Station uses a transparent material called succinonitrile that behaves like a metal to study this problem. Video images sent to the ground allow scientists to watch the behavior of the bubbles as they control the melting and freezing of the material. The bubbles do not float to the top of the material in microgravity, so they can study their interactions.

  4. Bioinspired Design: Magnetic Freeze Casting

    NASA Astrophysics Data System (ADS)

    Porter, Michael Martin

    Nature is the ultimate experimental scientist, having billions of years of evolution to design, test, and adapt a variety of multifunctional systems for a plethora of diverse applications. Next-generation materials that draw inspiration from the structure-property-function relationships of natural biological materials have led to many high-performance structural materials with hybrid, hierarchical architectures that fit form to function. In this dissertation, a novel materials processing method, magnetic freeze casting, is introduced to develop porous scaffolds and hybrid composites with micro-architectures that emulate bone, abalone nacre, and other hard biological materials. This method uses ice as a template to form ceramic-based materials with continuously, interconnected microstructures and magnetic fields to control the alignment of these structures in multiple directions. The resulting materials have anisotropic properties with enhanced mechanical performance that have potential applications as bone implants or lightweight structural composites, among others.

  5. Fatigue characteristics of cast iron

    SciTech Connect

    Herrera, J.M.; Spencer, P.R.; Tarin, P.; Stafford, S.W. . Dept. of Mechanical Engineering)

    1994-07-01

    Fatigue results from cyclic or alternating loading with the fracture developing as a result of crack initiation and growth. For a crack to propagate, it is necessary for the crack to open and for the stresses at the crack tip to exceed the tensile stress of the material. If the tensile stresses at the crack tip are not present or are below a critical value, the crack will not propagate. Cast iron was tested under fatigue loading where the stresses were mainly in the compressive region. The lack of tensile stresses increased the range and combination of loading necessary to induced fatigue failure. A Goodman diagram for design purposes were developed. This diagram can be generated from data obtained form simple tension, compression, and rotating-beam fatigue tests. The results of these tests actually indicate a significantly larger region for safe design recommendations.

  6. Effect of Some Parameters on the Cast Component Properties in Hot Chamber Die Casting

    NASA Astrophysics Data System (ADS)

    Singh, Rupinder; Singh, Harvir

    2015-11-01

    Hot chamber die casting process is designed to achieve high dimensional accuracy for small products by forcing molten metal under high pressure into reusable moulds, called dies. The present research work is aimed at study of some parameters (as a case study of spring adjuster) on cast component properties in hot chamber die casting process. Three controllable factors of the hot chamber die casting process (namely: pressure at second phase, metal pouring temperature and die opening time) were studied at three levels each by Taguchi's parametric approach and single-response optimization was conducted to identify the main factors controlling surface hardness, dimensional accuracy and weight of the casting. Castings were produced using aluminium alloy, at recommended parameters through hot chamber die casting process. Analysis shows that in hot chamber die casting process the percentage contribution of second phase pressure, die opening time, metal pouring temperature for surface hardness is 82.48, 9.24 and 6.78 % respectively. While in the case of weight of cast component the contribution of second phase pressure is 94.03 %, followed by metal pouring temperature and die opening time (4.58 and 0.35 % respectively). Further for dimensional accuracy contribution of die opening time is 76.97 %, metal pouring temperature is 20.05 % and second phase pressure is 1.56 %. Confirmation experiments were conducted at an optimal condition showed that the surface hardness, dimensional accuracy and weight of the castings were improved significantly.

  7. AMCC casting development. Volume 1: Executive Summary

    NASA Astrophysics Data System (ADS)

    1995-03-01

    The Advanced Combustion Chamber Casting (AMCC) has been a technically challenging part due to its size, configuration, and alloy type. The height and weight of the wax pattern assembly necessitated the development of a hollow gating system to ensure structural integrity of the shell throughout the investment process. The complexity in the jacket area of the casting required the development of an innovative casting technology that PCC has termed 'TGC' or Thermal Gradient Control. This method, of setting up thermal gradients in the casting during solidification, represents a significant process improvement for PCC and has been successfully implemented on other programs. Metallurgical integrity of the final four castings was very good. Only the areas of the parts that utilized 'TGC Shape & Location System #2' showed any significant areas of microshrinkage when evaluated by non-destructive tests. Alumina oxides detected by FPI on the 'float' surfaces (top sid surfaces of the casting during solidification) of the part were almost entirely less than the acceptance criteria of .032 inches in diameter. Destructive chem mill of the castings was required to determine the effect of the process variables used during the processing of these last four parts (with the exception of the 'Shape & Location of TGC' variable).

  8. Characterization of Technetium Speciation in Cast Stone

    SciTech Connect

    Um, Wooyong; Jung, Hun Bok; Wang, Guohui; Westsik, Joseph H.; Peterson, Reid A.

    2013-11-11

    This report describes the results from laboratory tests performed at Pacific Northwest National Laboratory (PNNL) for the U.S. Department of Energy (DOE) EM-31 Support Program (EMSP) subtask, “Production and Long-Term Performance of Low Temperature Waste Forms” to provide additional information on technetium (Tc) speciation characterization in the Cast Stone waste form. To support the use of Cast Stone as an alternative to vitrification for solidifying low-activity waste (LAW) and as the current baseline waste form for secondary waste streams at the Hanford Site, additional understanding of Tc speciation in Cast Stone is needed to predict the long-term Tc leachability from Cast Stone and to meet the regulatory disposal-facility performance requirements for the Integrated Disposal Facility (IDF). Characterizations of the Tc speciation within the Cast Stone after leaching under various conditions provide insights into how the Tc is retained and released. The data generated by the laboratory tests described in this report provide both empirical and more scientific information to increase our understanding of Tc speciation in Cast Stone and its release mechanism under relevant leaching processes for the purpose of filling data gaps and to support the long-term risk and performance assessments of Cast Stone in the IDF at the Hanford Site.

  9. NWIS MEASUREMENTS FOR URANIUM METAL ANNULAR CASTINGS

    SciTech Connect

    MATTINGLY, J.K.; VALENTINE, T.E.; MIHALCZO, J.T.

    1998-03-13

    This report describes measurements performed with annular uranium metal castings of different enrichments to investigate the use of {sup 252}Cf-source-driven noise analysis measurements as a means to quantify the amount of special nuclear material (SNM) in the casting. This work in FY 97 was sponsored by the Oak Ridge Y-12 Plant and the DOE Office of Technology Development Programs. Previous measurements and calculational studies have shown that many of the signatures obtained from the source-driven measurement are very sensitive to fissile mass. Measurements were performed to assess the applicability of this method to standard annular uranium metal castings at the Oak Ridge Y-12 plant under verification by the International Atomic Energy Agency (IAEA) using the Nuclear Weapons Identification System (NWIS) processor. Before the measurements with different enrichments, a limited study of source-detector-casting moderator configurations was performed to enhance the correlated information. These configurations consisted of a casting with no reflector and with various thicknesses of polyethylene reflectors up to 10.16 cm in 2.54 cm steps. The polyethylene moderator thickness of 7.62 cm was used for measurements with castings of different enrichments reported here. The sensitivity of the measured parameters to fissile mass was investigated using four castings each with a different enrichment. The high sensitivity of this measurement method to fissile mass and to other material and configurations provides some advantages over existing safeguards methods.

  10. AMCC casting development. Volume 1: Executive Summary

    NASA Technical Reports Server (NTRS)

    1995-01-01

    The Advanced Combustion Chamber Casting (AMCC) has been a technically challenging part due to its size, configuration, and alloy type. The height and weight of the wax pattern assembly necessitated the development of a hollow gating system to ensure structural integrity of the shell throughout the investment process. The complexity in the jacket area of the casting required the development of an innovative casting technology that PCC has termed 'TGC' or Thermal Gradient Control. This method, of setting up thermal gradients in the casting during solidification, represents a significant process improvement for PCC and has been successfully implemented on other programs. Metallurgical integrity of the final four castings was very good. Only the areas of the parts that utilized 'TGC Shape & Location System #2' showed any significant areas of microshrinkage when evaluated by non-destructive tests. Alumina oxides detected by FPI on the 'float' surfaces (top sid surfaces of the casting during solidification) of the part were almost entirely less than the acceptance criteria of .032 inches in diameter. Destructive chem mill of the castings was required to determine the effect of the process variables used during the processing of these last four parts (with the exception of the 'Shape & Location of TGC' variable).

  11. The continuous production of stir cast material

    NASA Astrophysics Data System (ADS)

    Hamoen, A.

    1986-06-01

    The production of AlSi8 extrusion billets using a semicontinuous caster is described. The continuous casting process and the process parameters are outlined. The mathematical model, developed to calculate the temperature distribution within the billet during casting as a function of the process parameters, is explained. Quality control focussed on inversion segregation which causes the formation of a surface layer with a different structure and composition, imposing peeling of billets. Product development focussed on the production of stir-cast material of the same AlSi8 alloy. The use of AlSi8 as a wrought alloy by modification of the structure by stirring is discussed.

  12. Improved Slip Casting Of Ceramic Models

    NASA Technical Reports Server (NTRS)

    Buck, Gregory M.; Vasquez, Peter; Hicks, Lana P.

    1994-01-01

    Improved technique of investment slip casting developed for making precise ceramic wind-tunnel models. Needed in wind-tunnel experiments to verify predictions of aerothermodynamical computer codes. Ceramic materials used because of their low heat conductivities and ability to survive high temperatures. Present improved slip-casting technique enables casting of highly detailed models from aqueous or nonaqueous solutions. Wet shell molds peeled off models to ensure precise and undamaged details. Used at NASA Langley Research Center to form superconducting ceramic components from nonaqueous slip solutions. Technique has many more applications when ceramic materials developed further for such high-strength/ temperature components as engine parts.

  13. Methods for Casting Subterranean Ant Nests

    PubMed Central

    Tschinkel, Walter R.

    2010-01-01

    The study of subterranean ant nests has been impeded by the difficulty of rendering their structures in visible form. Here, several different casting materials are shown to make perfect casts of the underground nests of ants. Each material (dental plaster, paraffin wax, aluminum, zinc) has advantages and limitations, which are discussed. Some of the materials allow the recovery of the ants entombed in the casts, allowing a census of the ants to be connected with features of their nest architecture. The necessary equipment and procedures are described in the hope that more researchers will study this very important aspect of ant natural history. PMID:20673073

  14. Fractal analysis of complex microstructure in castings

    SciTech Connect

    Lu, S.Z.; Lipp, D.C.; Hellawell, A.

    1995-12-31

    Complex microstructures in castings are usually characterized descriptively which often raises ambiguity and makes it difficult to relate the microstructure to the growth kinetics or mechanical properties in processing modeling. Combining the principle of fractal geometry and computer image processing techniques, it is feasible to characterize the complex microstructures numerically by the parameters of fractal dimension, D, and shape factor, a, without ambiguity. Procedures of fractal measurement and analysis are described, and a test case of its application to cast irons is provided. The results show that the irregular cast structures may all be characterized numerically by fractal analysis.

  15. The effect of casting temperature on the fatigue properties of cast nickel aluminide alloys

    SciTech Connect

    Gieseke, B.; Sikka, V.K.

    1991-01-01

    The results of high cycle fatigue tests at 650{degree}C on several cast Ni{sub 3}Al alloys are reported and compared to cast IN-713C. These alloys include IC-221M and several variations to the IC-221M composition. The effect of casting temperature is investigated using castings poured at three different temperatures spanning a 56{degree}C range. The results show that IC-221M cast at the highest temperature has the best fatigue strength, exceeding that for IN-713C. In these alloys, crack initiation occurs at shrinkage microporosity and the effect of casting temperature on porosity is related to the observed differences in fatigue lives. 11 refs., 4 figs.

  16. GRINDING ROOM AT SOUTHERN DUCTILE CASTING COMPANY, BESSEMER FOUNDRY SHOWING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    GRINDING ROOM AT SOUTHERN DUCTILE CASTING COMPANY, BESSEMER FOUNDRY SHOWING WHEELABORATOR THAT IMPALE SHOT AT TUMBLING CASTINGS TO REMOVE EXCESS SURFACE METALS AND SAND; ANNEALING OVENS TO HEAT CERTAIN CASTINGS TO ACHIEVE A DESIRED CHARACTERISTIC; AND GRINDING WHEELS USED TO REMOVE GATES. - Southern Ductile Casting Company, Grinding & Shipping, 2217 Carolina Avenue, Bessemer, Jefferson County, AL

  17. 21 CFR 888.5960 - Cast removal instrument.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Cast removal instrument. 888.5960 Section 888.5960...) MEDICAL DEVICES ORTHOPEDIC DEVICES Surgical Devices 888.5960 Cast removal instrument. (a) Identification. A cast removal instrument is an AC-powered, hand-held device intended to remove a cast from...

  18. 21 CFR 888.5960 - Cast removal instrument.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Cast removal instrument. 888.5960 Section 888.5960...) MEDICAL DEVICES ORTHOPEDIC DEVICES Surgical Devices 888.5960 Cast removal instrument. (a) Identification. A cast removal instrument is an AC-powered, hand-held device intended to remove a cast from...

  19. 21 CFR 888.5960 - Cast removal instrument.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Cast removal instrument. 888.5960 Section 888.5960...) MEDICAL DEVICES ORTHOPEDIC DEVICES Surgical Devices 888.5960 Cast removal instrument. (a) Identification. A cast removal instrument is an AC-powered, hand-held device intended to remove a cast from...

  20. 49 CFR 192.275 - Cast iron pipe.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Cast iron pipe. 192.275 Section 192.275... Cast iron pipe. (a) Each caulked bell and spigot joint in cast iron pipe must be sealed with mechanical leak clamps. (b) Each mechanical joint in cast iron pipe must have a gasket made of a...

  1. 21 CFR 888.5960 - Cast removal instrument.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Cast removal instrument. 888.5960 Section 888.5960...) MEDICAL DEVICES ORTHOPEDIC DEVICES Surgical Devices 888.5960 Cast removal instrument. (a) Identification. A cast removal instrument is an AC-powered, hand-held device intended to remove a cast from...

  2. 21 CFR 888.5960 - Cast removal instrument.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cast removal instrument. 888.5960 Section 888.5960...) MEDICAL DEVICES ORTHOPEDIC DEVICES Surgical Devices 888.5960 Cast removal instrument. (a) Identification. A cast removal instrument is an AC-powered, hand-held device intended to remove a cast from...

  3. 49 CFR 192.275 - Cast iron pipe.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Cast iron pipe. 192.275 Section 192.275... Cast iron pipe. (a) Each caulked bell and spigot joint in cast iron pipe must be sealed with mechanical leak clamps. (b) Each mechanical joint in cast iron pipe must have a gasket made of a...

  4. 49 CFR 192.275 - Cast iron pipe.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Cast iron pipe. 192.275 Section 192.275... Cast iron pipe. (a) Each caulked bell and spigot joint in cast iron pipe must be sealed with mechanical leak clamps. (b) Each mechanical joint in cast iron pipe must have a gasket made of a...

  5. Basic Casting from A to Z. Student's Instruction Booklet.

    ERIC Educational Resources Information Center

    Zebco, Tulsa, OK.

    A profusely illustrated student instruction booklet contains step-by-step directions and diagrams for learning four basic casting techniques. Separate sections cover basic spin-casting, spinning, bait-casting, and fly-casting. Each section details recommended equipment (reel, rod, line, plug, tackle, lures, leaders, flies), describes specific

  6. Diabetic Neuropathy: What is a Total Contact Cast?

    MedlinePLUS

    MENU Return to Web version Diabetic Neuropathy | What is a Total Contact Cast? What is a total contact cast? A total contact cast is a cast used to treat ulcers (serious, deep sores) on a person’s foot. It consists of a fiberglass shell that fits around your leg and foot very ...

  7. 49 CFR 192.275 - Cast iron pipe.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Cast iron pipe. 192.275 Section 192.275... Cast iron pipe. (a) Each caulked bell and spigot joint in cast iron pipe must be sealed with mechanical leak clamps. (b) Each mechanical joint in cast iron pipe must have a gasket made of a...

  8. 49 CFR 192.275 - Cast iron pipe.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Cast iron pipe. 192.275 Section 192.275... Cast iron pipe. (a) Each caulked bell and spigot joint in cast iron pipe must be sealed with mechanical leak clamps. (b) Each mechanical joint in cast iron pipe must have a gasket made of a...

  9. [Cast fractures of dental Ni-Cr alloys (author's transl)].

    PubMed

    Takahashi, J; Kaneda, S; Okazaki, M; Doi, Y; Moriwaki, Y; Kimura, H

    1981-10-01

    Cast fractures of Ni-Cr alloys were investigated by means of scanning electron microscopy, energy dispersive X-ray spectrometry, electron-probe microanalysis, density measurements, setting and thermal expansion measurements and compressive tests. Three-Ni-Cr alloys for crowns and bridges were cast in spiral configurations by an argon-arc pressured type or an induction argon-pressured type-casting machine. The amount of cast fracture increase with an increase in cast temperature, but not with an increase of holding time at cast temperature. Ni-Cr alloys have more cast fractures in a phosphate-bonded investment than in a gypsum-bonded cristobalite investment. Fracture surfaces have an exposed dendrite structure, indicating the presence of cast porosity. The trigger of cast crack can be a cast porosity and the propagation of crack to fracture may be mainly due to the strength of investments. PMID:7038000

  10. Roll Casting of Aluminum Alloy Clad Strip

    SciTech Connect

    Nakamura, R.; Tsuge, H.; Haga, T.; Watari, H.; Kumai, S.

    2011-01-17

    Casting of aluminum alloy three layers of clad strip was tried using the two sets of twin roll casters, and effects of the casting parameters on the cladding conditions were investigated. One twin roll caster was mounted on the other twin roll caster. Base strip was 8079 aluminum alloy and overlay strips were 6022 aluminum alloy. Effects of roll-load of upper and lower casters and melt temperature of the lower caster were investigated. When the roll-load of the upper and lower caster was large enough, the overlay strip could be solidified and be connected. The overlay strip could be connected when the melt of the overlay strip cast by the lower caster was low enough. Sound three layers of clad strip could be cast by proper conditions.

  11. Open Cast Mining: An Environmental Issue.

    ERIC Educational Resources Information Center

    McPartland, Michael

    1993-01-01

    Presents a case study in which students investigate the environmental issue of open cast coal mining. Students examine the issue from different perspectives; interpret the available evidence; draw appropriate conclusions; and evaluate such conclusions. (MDH)

  12. Thermal transport properties of grey cast irons

    SciTech Connect

    Hecht, R.L.; Dinwiddie, R.B.; Porter, W.D.; Wang, Hsin

    1996-10-01

    Thermal diffusivity and thermal conductivity of grey cast iron have been measured as a function of graphite flake morphology, chemical composition, and position in a finished brake rotor. Cast iron samples used for this investigation were cut from ``step block`` castings designed to produce iron with different graphite flake morphologies resulting from different cooling rates. Samples were also machined from prototype alloys and from production brake rotors representing a variation in foundry practice. Thermal diffusivity was measured at room and elevated temperatures via the flash technique. Heat capacity of selected samples was measured with differential scanning calorimetry, and these results were used to calculate the thermal conductivity. Microstructure of the various cast iron samples was quantified by standard metallography and image analysis, and the chemical compositions were determined by optical emission spectroscopy.

  13. Caste and Language in Jaffna Society.

    ERIC Educational Resources Information Center

    Suseendirarajah, S.

    1978-01-01

    Caste and language in the Jaffna Hindu Tamil society were correlated based on data collected from sample villages in the Jaffna peninsula, where the political and economic ascendancy of the landlords was very dominant in the recent past. (SW)

  14. Vacuum casting of thick polymeric films

    NASA Technical Reports Server (NTRS)

    Cuddihy, E. F.; Moacanin, J.

    1979-01-01

    Bubble formation and layering, which often plague vacuum-evaporated films, are prevented by properly regulating process parameters. Vacuum casting may be applicable to forming thick films of other polymer/solvent solutions.

  15. Slip casting of advanced ceramics and composites

    NASA Astrophysics Data System (ADS)

    Schilling, C. H.; Aksay, I. A.

    1987-03-01

    Particle packing arrangements in slip cast (colloidal filtration) articles uniquely affect the evolution of grain size and porosity defect distributions during sintering. These particle packing arrangements are influenced by the physical properties of colloidal structures in suspension and the resulting processes of agglomerate restructuring and pore closure during consolidation. Key parameters affecting cast layer packing structures are the particle size distribution, interparticle potential, hydrodynamic stresses in suspensions, and the combined effect of hydrodynamic and compaction stresses in cast layers. Experiments with electrostatically stabilized aqueous alumina systems illustrate specific effects of interparticle potential on slip casting rates and microstructure evolution during sintering. In addition, experiments were conducted that illustrate microstructure variations caused by differential sedimentation velocities and agglomerate growth kinetic effects.

  16. Advanced lost foam from casting technology

    SciTech Connect

    Bates, C. E.; Littleton, H. E.; Askeland, D.; Griffin, J.; Miller, B. A.; Sheldon, D. S.

    1996-05-01

    Previous research made significant advances in understanding the Lost Foam Casting (LFC) Process and clearly identified areas where additional research was needed to improve the process and make it more functional in an industrial environment. The current project focused on five areas listed as follows: Task 1: Precision Pattern Production Task 2: Pattern Coating Consistency Task 3: Sand Fill and Compaction Effects Task 4: Pattern Gating Task 5: Mechanical Properties of Castings. This report summarizes the work done under the current contract in all five areas in the period of October 1, 1994 through December 31, 1995. Twenty-eight (28) companies jointly participate in the project. These companies represent a variety of disciplines, including pattern designers, pattern producers, coating manufacturers, plant design companies, compaction equipment manufacturers, casting producers, and casting buyers.

  17. Arc Casting Intermetallic Alloy (Materials Preparation Center)

    SciTech Connect

    2010-01-01

    Arc casting of intermetallic (La-Ni-Sn) AB5 alloy used for metal hydride hydrogen storage. Upon solidification the Sn is partially rejected and increases in concentration in the remaining liquid. Upon completing solidification there is a great deal of internal stress in the ingot. As the ingot cools further the stress is relieved. This material was cast at the Ames Laboratorys Materials Preparation Center http://www.mpc.ameslab.gov

  18. Embedding Optical Fibers In Cast Metal Parts

    NASA Technical Reports Server (NTRS)

    Gibler, William N.; Atkins, Robert A.; Lee, Chung E.; Taylor, Henry F.

    1995-01-01

    Use of metal strain reliefs eliminates breakage of fibers during casting process. Technique for embedding fused silica optical fibers in cast metal parts devised. Optical fiber embedded in flange, fitting, or wall of vacuum or pressure chamber, to provide hermetically sealed feedthrough for optical transmission of measurement or control signals. Another example, optical-fiber temperature sensor embedded in metal structural component to measure strain or temperature inside component.

  19. Combination Of Investment And Centrifugal Casting

    NASA Technical Reports Server (NTRS)

    Creeger, Gordon A.

    1994-01-01

    Modifications, including incorporation of centrifugal casting, made in investment-casting process reducing scrap rate. Used to make first- and second-stage high-pressure-fuel-turbopump nozzles, containing vanes with thin trailing edges and other thin sections. Investment mold spun for short time while being filled, and stopped before solidification occurs. Centrifugal force drives molten metal into thin trailing edges, ensuring they are filled. With improved filling, preheat and pour temperatures reduced and solidification hastened so less hot tearing.

  20. Generalized hair casts due to traction.

    PubMed

    Ozuguz, Pinar; Kacar, Seval; Takci, Zennure; Ekiz, Ozlem; Kalkan, Goknur; Bulbul Sen, Bilge

    2013-01-01

    Peripilar keratin casts, also called pseudonits or hair casts, are thin, elongated, greyish-white, cylindrical, sleeve-like structures that encircle the hair shaft and can easily be slid along the hair. They may be clinically misdiagnosed as nits. In addition to physical removal, keratolytic lotions or shampoos are helpful. We report an 11-year-old girl with pseudonits. Although it is not a rare condition, underdiagnosis is common. PMID:23909653

  1. Apollo 14 composite casting demonstration

    NASA Technical Reports Server (NTRS)

    1971-01-01

    This program assisted in the design and implementation of the composite casting demonstration for the Apollo 14 mission. Both flight and control samples were evaluated. Some conclusions resulting from a comparison of the flight and control samples were: (1) Solidification in neither the flight nor control samples was truly directional. (2) Apparent intermittent contact of the melt with the container in the flight samples led to unusual nucleation and growth structures. (3) There was greater uniformity, on a macro scale, of both pores and structural features in the flight sample; presumably the result of the reduced gravity conditions. (4) It seems quite feasible to produce enhanced dispersions of gases and dense phases in a melt which is solidified in reduced gravity. (5) A two-stage heating/cooling cycle may help directional solidification. (6) Sample materials should be selected from materials in which the dispersant fully wets the matrix material. (7) Experiments should be conducted in two modes: (1) where the melt is in good thermal contact with the container, and (2) where the melt is in a free-float condition.

  2. Low Background Micromegas in CAST

    NASA Astrophysics Data System (ADS)

    Garza, J. G.; Aune, S.; Aznar, F.; Calvet, D.; Castel, J. F.; Christensen, F. E.; Dafni, T.; Davenport, M.; Decker, T.; Ferrer-Ribas, E.; Galán, J.; García, J. A.; Giomataris, I.; Hill, R. M.; Iguaz, F. J.; Irastorza, I. G.; Jakobsen, A. C.; Jourde, D.; Mirallas, H.; Ortega, I.; Papaevangelou, T.; Pivovaroff, M. J.; Ruz, J.; Tomás, A.; Vafeiadis, T.; Vogel, J. K.

    2015-11-01

    Solar axions could be converted into x-rays inside the strong magnetic field of an axion helioscope, triggering the detection of this elusive particle. Low background x-ray detectors are an essential component for the sensitivity of these searches. We report on the latest developments of the Micromegas detectors for the CERN Axion Solar Telescope (CAST), including technological pathfinder activities for the future International Axion Observatory (IAXO). The use of low background techniques and the application of discrimination algorithms based on the high granularity of the readout have led to background levels below 10-6 counts/keV/cm2/s, more than a factor 100 lower than the first generation of Micromegas detectors. The best levels achieved at the Canfranc Underground Laboratory (LSC) are as low as 10-7 counts/keV/cm2/s, showing good prospects for the application of this technology in IAXO. The current background model, based on underground and surface measurements, is presented, as well as the strategies to further reduce the background level. Finally, we will describe the R&D paths to achieve sub-keV energy thresholds, which could broaden the physics case of axion helioscopes.

  3. Reinforcement of Aluminum Castings with Dissimilar Metals

    SciTech Connect

    Han, Q

    2004-01-07

    The project ''Reinforcement of Aluminum Casting with Dissimilar Metal'' was a Cooperative Research and Development Agreements (CRADAs) between Oak Ridge National Laboratory (ORNL) and Cummins Inc. This project, technologies have been developed to reinforce aluminum castings with steel insert. Defect-free bond between the steel insert and the aluminum casting has been consistently obtained. The push-out experiment indicated that the bond strength is higher than that of the Al-Fin method. Two patents have been granted to the project team that is comprised of Cummins Inc. and ORNL. This report contains four sections: the coating of the steel pins, the cast-in method, microstructure characterization, and the bond strength. The section of the coating of the steel pins contains coating material selection, electro-plating technique for plating Cu and Ni on steel, and diffusion bonding of the coatings to the steel. The section of cast-in method deals with factors that affecting the quality of the metallurgical bond between the coated steel and the aluminum castings. The results of microstructure characteristics of the bonding are presented in the microstructure characterization section. A push-out experiment and the results obtained using this method is described in the section of bond strength/mechanical property.

  4. Neutron radiography inspection of investment castings.

    PubMed

    Richards, W J; Barrett, J R; Springgate, M E; Shields, K C

    2004-10-01

    Investment casting, also known as the lost wax process, is a manufacturing method employed to produce near net shape metal articles. Traditionally, investment casting has been used to produce structural titanium castings for aero-engine applications with wall thickness less than 1 in (2.54 cm). Recently, airframe manufacturers have been exploring the use of titanium investment casting to replace components traditionally produced from forgings. Use of titanium investment castings for these applications reduces weight, cost, lead time, and part count. Recently, the investment casting process has been selected to produce fracture critical structural titanium airframe components. These airframe components have pushed the traditional inspection techniques to their physical limits due to cross sections on the order of 3 in (7.6 cm). To overcome these inspection limitations, a process incorporating neutron radiography (n-ray) has been developed. In this process, the facecoat of the investment casting mold material contains a cocalcined mixture of yttrium oxide and gadolinium oxide. The presence of the gadolinium oxide, allows for neutron radiographic imaging (and eventual removal and repair) of mold facecoat inclusions that remain within these thick cross sectional castings. Probability of detection (POD) studies have shown a 3 x improvement of detecting a 0.050 x 0.007 in2 (1.270 x 0.178 mm2) inclusion of this cocalcined material using n-ray techniques when compared to the POD using traditional X-ray techniques. Further, it has been shown that this n-ray compatible mold facecoat material produces titanium castings of equal metallurgical quality when compared to the traditional materials. Since investment castings can be very large and heavy, the neutron radiography facilities at the University of California, Davis McClellan Nuclear Radiation Center (UCD/MNRC) were used to develop the inspection techniques. The UCD/MNRC has very unique facilities that can handle large parts up to 39 ft (12 m) in length and 13 ft (4 m) high weighing up to 5000 lbs (2300 kg). These handling systems are robotically driven. The neutron radiographic system consists of a highly thermalized neutron beam. The neutron beam has an intensity of 5.6 x 10(6) n/cm2 s, with a L/D = 200 at a power of 2 MW. A divergent beam collimator is used which provides a beam of approximately 22 in (56 cm) in diameter at the film plane. A vacuum cassette with a gadolinium vapor deposited screen is used to collect the image. Exposure times can be as short as 3 min, or up to 30 min. PMID:15246417

  5. Methods and apparatuses for manufacturing monocrystalline cast silicon and monocrystalline cast silicon bodies for photovoltaics

    DOEpatents

    Stoddard, Nathan G. (Gettysburg, PA)

    2011-11-01

    Methods and apparatuses are provided for casting silicon for photovoltaic cells and other applications. With such methods and apparatuses, a cast body of monocrystalline silicon may be formed that is free of, or substantially free of, radially-distributed impurities and defects and having at least two dimensions that are each at least about 35 cm is provided.

  6. Methods and apparatus for manufacturing monocrystalline cast silicon and monocrystalline cast silicon bodies for photovoltaics

    DOEpatents

    Stoddard, Nathan G

    2014-01-14

    Methods and apparatuses are provided for casting silicon for photovoltaic cells and other applications. With such methods and apparatuses, a cast body of monocrystalline silicon may be formed that is free of, or substantially free of, radially-distributed impurities and defects and having at least two dimensions that are each at least about 35 cm is provided.

  7. National Metal Casting Research Institute final report. Volume 2, Die casting research

    SciTech Connect

    Jensen, D.

    1994-06-01

    Four subprojects were completed: development and evaluation of die coatings, accelerated die life characterization of die materials, evaluation of fluid flow and solidification modeling programs, selection and characterization of Al-based die casting alloys, and influence of die materials and coatings on die casting quality.

  8. Advanced Pattern Material for Investment Casting Applications

    SciTech Connect

    F. Douglas Neece Neil Chaudhry

    2006-02-08

    Cleveland Tool and Machine (CTM) of Cleveland, Ohio in conjunction with Harrington Product Development Center (HPDC) of Cincinnati, Ohio have developed an advanced, dimensionally accurate, temperature-stable, energy-efficient and cost-effective material and process to manufacture patterns for the investment casting industry. In the proposed technology, FOPAT (aFOam PATtern material) has been developed which is especially compatible with the investment casting process and offers the following advantages: increased dimensional accuracy; increased temperature stability; lower cost per pattern; less energy consumption per pattern; decreased cost of pattern making equipment; decreased tooling cost; increased casting yield. The present method for investment casting is "the lost wax" process, which is exactly that, the use of wax as a pattern material, which is then melted out or "lost" from the ceramic shell. The molten metal is then poured into the ceramic shell to produce a metal casting. This process goes back thousands of years and while there have been improvements in the wax and processing technology, the material is basically the same, wax. The proposed technology is based upon an established industrial process of "Reaction Injection Molding" (RIM) where two components react when mixed and then "molded" to form a part. The proposed technology has been modified and improved with the needs of investment casting in mind. A proprietary mix of components has been formulated which react and expand to form a foam-like product. The result is an investment casting pattern with smooth surface finish and excellent dimensional predictability along with the other key benefits listed above.

  9. Precision Casting via Advanced Simulation and Manufacturing

    NASA Technical Reports Server (NTRS)

    1997-01-01

    A two-year program was conducted to develop and commercially implement selected casting manufacturing technologies to enable significant reductions in the costs of castings, increase the complexity and dimensional accuracy of castings, and reduce the development times for delivery of high quality castings. The industry-led R&D project was cost shared with NASA's Aerospace Industry Technology Program (AITP). The Rocketdyne Division of Boeing North American, Inc. served as the team lead with participation from Lockheed Martin, Ford Motor Company, Howmet Corporation, PCC Airfoils, General Electric, UES, Inc., University of Alabama, Auburn University, Robinson, Inc., Aracor, and NASA-LeRC. The technical effort was organized into four distinct tasks. The accomplishments reported herein. Task 1.0 developed advanced simulation technology for core molding. Ford headed up this task. On this program, a specialized core machine was designed and built. Task 2.0 focused on intelligent process control for precision core molding. Howmet led this effort. The primary focus of these experimental efforts was to characterize the process parameters that have a strong impact on dimensional control issues of injection molded cores during their fabrication. Task 3.0 developed and applied rapid prototyping to produce near net shape castings. Rocketdyne was responsible for this task. CAD files were generated using reverse engineering, rapid prototype patterns were fabricated using SLS and SLA, and castings produced and evaluated. Task 4.0 was aimed at developing technology transfer. Rocketdyne coordinated this task. Casting related technology, explored and evaluated in the first three tasks of this program, was implemented into manufacturing processes.

  10. Predicting Pattern Tooling and Casting Dimensions for Investment Casting - Phase II

    SciTech Connect

    Sabau, Adrian S

    2005-09-01

    The investment casting process allows the production of complex-shape parts and close dimensional tolerances. One of the most important phases in the investment casting process is the design of the pattern die. Pattern dies are used to create wax patterns by injecting wax into dies. The wax patterns are used to create a ceramic shell by the application of a series of ceramic coatings, and the alloy is cast into the dewaxed shell mold (Fig. 1.1). However, the complexity of shape and the close dimensional tolerances required in the final casting make it difficult to determine tooling dimensions. The final linear dimension of the casting depends on the cumulative effects of the linear expansions or contractions in each step of the investment casting process (Fig. 1.2). In most cases, the mold geometry or cores restrict the shrinkage of the pattern or the cast part, and the final casting dimensions may be affected by time-dependent processes such as viscoelastic deformation of the wax, and viscoplastic creep and plastic deformations of the shell and alloy. The pattern die is often reworked several times to produce castings whose dimensions are within acceptable tolerances. To date, investment casting technology has been based on hands-on training and experience. Technical literature is limited to experimental, phenomenological studies aimed at obtaining empirical correlations for quick and easy application in industry. The goal of this project was to predict casting dimensions for investment castings in order to meet blueprint nominal during the first casting run. Several interactions have to be considered in a coupled manner to determine the shrinkage factors: these are the die-wax, wax-shell, and shell-alloy interactions (as illustrated in Fig. 1.3). In this work, the deformations of the die-wax and shell-alloy systems were considered in a coupled manner, while the coupled deformation of the wax-shell system was not considered. Future work is needed in order to deliver to industry a computer program in which all three systems are coupled for determining the dimensions of the wax pattern, the shell mold, and casting in a sequential but coupled manner.

  11. Microstructure of thin-wall ductile iron castings

    SciTech Connect

    Dogan, Omer N.; Schrems, Karol K.; Hawk, Jeffrey A.; Druschitz, A.P.

    2001-10-01

    The automotive industry is seeking to replace current car parts made of aluminum and iron castings with thin wall (down to 2 mm) iron castings to reduce the cost and weight of automobiles. The mechanical properties of thin wall ductile iron castings are affected strongly by the thickness of the castings. The thinner castings cool at a faster rate, and microstructural features that form during solidification, and subsequently, transform in the solid state, are strongly dependent on a geometrical parameter related to the ratio of surface area-to-volume of the casting. As this ratio becomes larger, castings cool faster. As a result, the nodule count on the observation plane of the specimens increases dramatically (>2000 nodules/mm2 in most specimens), i.e. as the thickness of castings decreases. Also, the matrix of the thin walled ductile iron castings becomes more ferritic as the ratio of surface area-to-volume decreases.

  12. INDIAN CASTE SYSTEM: HISTORICAL AND PSYCHOANALYTIC VIEWS.

    PubMed

    Vallabhaneni, Madhusudana Rao

    2015-12-01

    This paper elucidates the historical origins and transformations of India's caste system. Surveying the complex developments over many centuries, it points out that three positions have been taken in this regard. One suggests that the caste one is born into can be transcended within one's lifetime by performing good deeds. The other declares caste to be immutable forever. And, the third says that one can be reborn into a higher caste if one lives a virtuous life. Moving on to the sociopolitical realm, the paper notes how these positions have been used and exploited. The paper then attempts to anchor the existence and purpose of the Hindu caste system in Freud's ideas about group psychology and Klein's proposals of splitting and projective identification. The paper also deploys the large group psychology concepts of Volkan and the culturally nuanced psychoanalytic anthropology of Roland and Kakar. It concludes with delineating some ameliorative strategies for this tragic problem in the otherwise robust democratic society of India. PMID:26611129

  13. Superplasticity in Rapidly Solidified White Cast Irons

    NASA Astrophysics Data System (ADS)

    Ruano, Oscar A.; Eiselstein, Lawrence E.; Sherby, Oleg D.

    1982-10-01

    Superplastic properties of three different composition white cast irons were investigated in the temperature range of 630 to 725 C. Fine structures consisting of 1 to 2 ?m ferrite grains were developed in these materials by consolidation of rapidly solidified powders at intermediate temperatures below the A1 critical temperature. Tensile elongations of 1410 pct were found for a 3.0 pct C + 1.5 pct Cr white cast iron, 940 pct for a 3.0 pct C white cast iron, and 480 pct for a 2.4 pct C white cast iron when tested at 700 C and at a strain rate of 1 pct per minute. The superplastic white cast irons exhibited a high strain rate sensitivity exponent, m, of 0.5 and activation energies for plastic flow were found to be nearly equal to the activation energy for grain boundary self-diffusion in iron. These observations are in agreement with the creep behavior of superplastic materials controlled by grain boundary diffusion.

  14. [Reproduction of interocclusal relationship on stone casts].

    PubMed

    Arai, Y

    2000-12-01

    We fabricate a prosthesis by the indirect method. To fabricate a prosthesis functionally harmonized with the stomatognathic system, the interocclusal relationship must be reproduced on stone casts as accurately as possible. In this study, two subjects (one male, age 28; one female, age 31) were selected, and the occlusal contacts of complete arch stone casts made by three different impression methods were observed and compared with the true occlusal contacts in the intercuspal position in the mouth. To take the interocclusal records, we used a silicone bite checker. The following results were obtained. The occlusal contact points reproduced on the stone casts made by a conventional custom tray and a stock tray were rather low; that is, the number of occlusal contact points was less, and the size of the occlusal contact area was smaller, than in vivo. The states of the occlusal contact on the casts made by the same method differed from each other. On the bite-impression technique, the reproduction of occlusal contact was superior to that of the others. The shape, area, and number of contact regions under 60 micrometers were similar to contact regions under 30 micrometers in the mouth. There was no significant difference in reproduction between the custom tray and the stock tray. It is likely that the results were due to the distortion of the jaws and periodontal tissue during clenching at the intercuspal position, which could not be reproduced on the stone casts made by both the conventional custom and stock trays. PMID:11201196

  15. Robust digital watermarking using random casting method

    NASA Astrophysics Data System (ADS)

    Kim, Jin-Seob; Kim, Tae-Hyun; Kim, Eun-Soo

    2001-12-01

    In this paper, a new digital watermarking scheme based-on the random casting method in the DCT domain is proposed. In the conventional watermarking methods, the DCT-transformed watermark is casting to the high frequency coefficients of the original cover image and the watermark is sequentially embedded in the casting frequency. But this kind of watermarking scheme can be attacked easily by the pirates and unlawful users, because these methods might have some structured patterns by the sequential embedding and the fixed casting domain. Also this method might get the damaged stego-image and is not robust to the image compression algorithms. Therefore, in this paper, a new robust digital watermarking scheme is proposed. In this algorithm, the frequency coefficients of the DCT-transformed original cover-image in which the watermark is inserted are randomly selected. These random position values of the casting frequencies can be used as another secret-key together with the watermark-key. From some experimental results the proposed method is found to be more robust to the possible attacks than those of the conventional methods.

  16. Casting properties of Ni-Ti shape memory alloy.

    PubMed

    Takahashi, J; Okazaki, M; Kimura, H; Furuta, Y

    1984-04-01

    A Ni-45 wt% Ti (Ni-50 at % Ti) alloy was cast into molds of magnesia and silica investments by use of a dental argon-arc pressure casting machine with a copper crucible . The castings exhibited shape memory properties. The shape recovery process was sharper in the specimens cast in magnesia investment molds than in those cast in silica (phosphate-bonded) investment molds. The latter casting had a hard region of the periphery, suggesting that shape recovery process may be affected by reaction of molten metal with silica. Furthermore, the alloy possessed the adequate mechanical properties for consideration as crown-and-bridge prostheses. PMID:6736077

  17. Composites for Advanced Space Transportation Systems (CASTS)

    NASA Technical Reports Server (NTRS)

    Davis, J. G., Jr. (Compiler)

    1979-01-01

    A summary is given of the in-house and contract work accomplished under the CASTS Project. In July 1975 the CASTS Project was initiated to develop graphite fiber/polyimide matrix (GR/PI) composite structures with 589K (600 F) operational capability for application to aerospace vehicles. Major tasks include: (1) screening composites and adhesives, (2) developing fabrication procedures and specifications, (3) developing design allowables test methods and data, and (4) design and test of structural elements and construction of an aft body flap for the Space Shuttle Orbiter Vehicle which will be ground tested. Portions of the information are from ongoing research and must be considered preliminary. The CASTS Project is scheduled to be completed in September 1983.

  18. Cast Aluminum Alloy for High Temperature Applications

    NASA Technical Reports Server (NTRS)

    Lee, Jonathan A.

    2003-01-01

    Originally developed by NASA as high performance piston alloys to meet U.S. automotive legislation requiring low exhaust emission, the novel NASA alloys now offer dramatic increase in tensile strength for many other applications at elevated temperatures from 450 F (232 C) to about 750 F (400 C). It is an ideal low cost material for cast automotive components such as pistons, cylinder heads, cylinder liners, connecting rods, turbo chargers, impellers, actuators, brake calipers and rotors. It can be very economically produced from conventional permanent mold, sand casting or investment casting, with silicon content ranging from 6% to 18%. At high silicon levels, the alloy exhibits excellent dimensional stability, surface hardness and wear resistant properties.

  19. Hair casts due to a deodorant spray.

    PubMed

    Ena, Pasquale; Mazzarello, Vittorio; Chiarolini, Fausto

    2005-11-01

    A 7-year-old girl presented with itching and greyish-white sleeve-like structures in her hair. After ruling out other possible causes for the symptoms, such as nits and dandruff, it was determined that the patient was affected by hair casts. These are small cylindrical structures resembling louse eggs that encircle individual scalp hairs and are easily movable along the hair shafts. It was concluded that she had induced the condition through misuse of a deodorant body spray. Scanning electron microscopy combined with electron dispersive X-ray analysis (X-ray microanalysis) of the hair casts showed the chemical nature of the structures. Some elements present in the composition of the ingredients of the deodorant spray, such as aluminium, chlorine, silicon, magnesium and carbon, were also present in this uncommon type of hair casts. PMID:16197431

  20. Modeling microstructure development in gray cast irons

    NASA Astrophysics Data System (ADS)

    Goettsch, David D.; Dantzig, Jonathan A.

    1994-05-01

    Recent years have seen increasing use of solidification process modeling as a tool to aid in the analysis and elimination of manufacturing defects in castings. Grain size and other microstructural features such as second-phase morphology and distribution are the primary factors in determining the mechanical properties in cast metals. In this work, a representation of nucleation and growth kinetics for gray cast irons, based on a statistical description of the microstructure, has been coupled with a commercial finite-element method code for transient heat-flow calculation to determine microstructure. Features predicted include eutectic cell size, fractions of gray and white iron, graphite morphology, percent pearlite, percent ferrite, and pearlite spacing. The predicted microstructure can then be used to determine the strength and fatigue properties using published correlations. The theoretical development and results of the finite-elementbased model will be discussed and compared with experimental results.

  1. Salt Bath Oxinitriding of Gray Cast Iron

    NASA Astrophysics Data System (ADS)

    Ahmadi, M.; Teimouri, M.; Aliofkhazraee, M.; Mousavi Khoee, S. M.

    Salt bath oxinitriding is a duplex surface treatment developed to improve tribological and corrosion properties of ferrous materials. In this research, gray cast iron samples were nitrided at the temperature range of 480C-580C, and then oxidized in an oxidative salt bath. The phase composition of surface layer was identified by X-ray diffraction. Using a microhardness tester, hardness of nitrided gray cast iron was measured. Corrosion behavior of treated (nitrided and oxinitrided) samples was evaluated using potentiodynamic polarization technique in 3.5% NaCl solution. XRD analyses indicate that the surface layer in nitrided and oxinitrided samples is composed of ?-iron nitride (Fe2-3N) and magnetite (Fe3O4), respectively. Results show that the corrosion resistance of gray cast iron can be improved up to 170%.

  2. Fatigue of die cast zinc alloys

    SciTech Connect

    Schrems, K.K.; Dogan, O.N.; Goodwin, F.E.

    2006-04-01

    The rotating bending fatigue limit of die cast zinc alloy 2, alloy 3, alloy 5, AcuZinc 5, and ZA-8 were determined as a part of an on-going program by ILZRO into the mechanical properties of die cast zinc. The stress-life (S-N) curves of alloys 3, 5, AcuZinc 5, and ZA-8 were determined previously. This presentation reports the results of the S-N curve for Alloy 2 and the calculated fatigue limits for all five alloys. During the previous stress-life testing, the samples were stopped at 10 million cycles and the fatigue limit for alloy 3, alloy 5, and AcuZinc 5 appeared to be higher and the fatigue limit for ZA-8 appeared to be lower than the values reported in the literature. This was further investigated in alloy 5 and ZA-8 by testing continuous cast bulk alloy 5 and ZA-8.

  3. TiC reinforced cast chromium steels

    SciTech Connect

    Dogan, Omer N.; Rawers, James C.; Hawk, Jeffrey A.; Schrems, Karol K.

    2003-11-01

    A series of new titanium carbide reinforced cast chromium steels were developed for wear applications. Objective of the program was to enhance wear resistant alloys and, if possible, improve mechanical properties. The new steels which were melted in a vacuum induction furnace contained 12 Cr, 3-5 Ti, 1-2 C in weight percent. Alloying with Ti changed the precipitate microstructure from Cr carbide to TiC dispersed in a martensitic matrix. Yield strength and impact resistance improved with Ti alloying. Wear rates of the cast Cr/TiC steels, (determined from high- and low-stress abrasion tests, erosion test, and scratch tests) were generally lower than both the as-cast and heat-treated AISI type 440C steel and were often further reduced by increasing the Ti alloy concentration. The exceptions were the erosion test for which all materials had similar wear rate.

  4. A new casting defect healing technology

    SciTech Connect

    Hodge, E.S.; Reddoch, T.W.; Viswanathan, S.

    1997-01-01

    A new technology is presented for healing of defects in 356 aluminium alloys that provides economic upgrading of these cast alloys. It uses pneumatic isostatic forging (PIF) to produce high quality Al alloys products with enhanced mechanical properties uniform throughout the part, allowing higher design allowables and increased usage of Al alloy castings. The fundamental mechanism underlying PIF is a single mode plastic deformation process that uses isostatic application of pressures for 10-30 seconds at temperature. The process can be integrated in-line with other production operations, i.e., using the latent heat from the previous casting step. Results of applying the PIF process indicate lower cost and significant improvement in mechanical properties that rival and often exceed corresponding properties of other technologies like hot isostatic pressing and related processes. This process offers many advantages that are described in this paper in addition to presenting case histories of property enhancement by PIF and the mechanism responsible for property enhancement.

  5. Solvent casting flow from slot die

    NASA Astrophysics Data System (ADS)

    Lee, Semi; Nam, Jaewook

    2015-11-01

    A continuous solvent casting method using a slot die can precisely control the film thickness by adjusting the operating conditions, such as the belt speed and pumping rate, not the liquid property. Therefore, it is a suitable method for high precision continuous film production. In this particular method, the dope, or casting solution, is pumped through the feed slot to form a short curtain between the die and the moving belt. Although this method is widely used in producing films for various applications, it is difficult to find indepth analyses of such flow. In this study, we developed a finite element computational model for the steady-state two-dimensional sovent casting flow from the slot die. The effect of die configurations, rheological properties and operating conditions on the behavior and shape of the gas/liquid interfaces and the location of the dynamic contact line, which is the place where the dope meets the moving belt, were investigated.

  6. A fourier theory for cast shadows.

    PubMed

    Ramamoorthi, Ravi; Koudelka, Melissa; Belhumeur, Peter

    2005-02-01

    Cast shadows can be significant in many computer vision applications, such as lighting-insensitive recognition and surface reconstruction. Nevertheless, most algorithms neglect them, primarily because they involve nonlocal interactions in nonconvex regions, making formal analysis difficult. However, many real instances map closely to canonical configurations like a wall, a V-groove type structure, or a pitted surface. In particular, we experiment with 3D textures like moss, gravel, and a kitchen sponge, whose surfaces include canonical configurations like V-grooves. This paper takes a first step toward a formal analysis of cast shadows, showing theoretically that many configurations can be mathematically analyzed using convolutions and Fourier basis functions. Our analysis exposes the mathematical convolution structure of cast shadows and shows strong connections to recent signal-processing frameworks for reflection and illumination. PMID:15688567

  7. Variability of short arm cast application: the influence of experience using fibreglass tape and QuickCast.

    PubMed

    Cohen, M S

    1997-01-01

    A new short arm cast material which is heated to conform to the underlying limb was compared to conventional fibreglass tape. The time required for application, the pressures generated beneath the casts and the availability for digital motion were studied in three groups with varying lengths of casting experience. Results showed that the new immobilizer did not require additional time for application and provided similar interface pressures beneath the casts as compared to fibreglass tape. In addition, metacarpophalangeal joint motion was less restricted with the new casting experience. The shrinkable immobilizer thus offers an alternative to conventional fibreglass tape casts. PMID:9196621

  8. Mathematical Modeling of Surface Roughness of Castings Produced Using ZCast Direct Metal Casting

    NASA Astrophysics Data System (ADS)

    Chhabra, M.; Singh, R.

    2015-04-01

    Aim of this investigation is to develop a mathematical model for predicting surface roughness of castings produced using ZCast process by employing Buckingham's ?-theorem. A relationship has been proposed between surface roughness of castings and shell wall thickness of the shell moulds fabricated using 3D printer. Based on model, experiments were performed to obtain the surface roughness of aluminium, brass and copper castings produced using ZCast process based on 3D printing technique. Based on experimental data, three best fitted third-degree polynomial equations have been established for predicting the surface roughness of castings. The predicted surface roughness values were then calculated using established best fitted equations. An error analysis was performed to compare the experimental and predicted data. The average prediction errors obtained for aluminium, brass and copper castings are 10.6, 2.43 and 3.12 % respectively. The obtained average surface roughness (experimental and predicted) values of castings produced are acceptable with the sand cast surface roughness values range (6.25-25 m).

  9. Compound cast product and method for producing a compound cast product

    DOEpatents

    Meyer, Thomas N. (3987 Murray Highlands Cir., Murrysville, PA 15668-1747); Viswanathan, Srinath (1104 Albermarle La., Knoxville, TN 37923)

    2002-09-17

    A compound cast product is formed in a casting mold (14) having a mold cavity (16) sized and shaped to form the cast product. A plurality of injectors (24) is supported from a bottom side (26) of the casting mold (14). The injectors (24) are in fluid communication with the mold cavity (16) through the bottom side (26) of the casting mold (14). A molten material holder furnace (12) is located beneath the casting mold (14). The holder furnace (12) defines molten material receiving chambers (36) configured to separately contain supplies of two different molten materials (37, 38). The holder furnace (12) is positioned such that the injectors (24) extend downward into the receiving chamber (36). The receiving chamber (36) is separated into at least two different flow circuits (51, 52). A first molten material (37) is received in a first flow circuit (51), and a second molten material (38) is received into a second flow circuit (52). The first and second molten materials (37, 38) are injected into the mold cavity (16) by the injectors (24) acting against the force of gravity. The injectors (24) are positioned such that the first and second molten materials (37, 38) are injected into different areas of the mold cavity (16). The molten materials (37, 38) are allowed to solidify and the resulting compound cast product is removed from the mold cavity (16).

  10. Modeling of casting microstructures and defects

    SciTech Connect

    Shapiro, A.B.; Summers, L.T.; Eckels, D.J.; Sahai, V.

    1997-09-26

    Casting is an ancient art that has been a trial-and-error process for more than 4000 years. To predict the size, shape, and quality of a cast product, casting manufacturers typically cast full-size prototypes. If one part of the process is done incorrectly, the entire process is repeated until an acceptable product is achieved. One way to reduce the time, cost, and waste associated with casting is to use computer modeling to predict not only the quality of a product on the macro- scale, such as distortion and part shape, but also on the micro-scale such as grain defects. Modeling of solidification is becoming increasingly feasible with the advent of parallel computers. There are essentially two approaches to solidification modeling.The first is that of macro-modeling where heat transfer codes model latent heat release during solidification as a constant and based solely on the local temperature. This approach is useful in predicting large scale distortion and final part shape. The second approach, micro-modeling, is more fundamental. The micro-models estimate the latent heat release during solidification using nucleation and grain growth kinetics. Micro-models give insight into cast grain morphology and show promise in the future to predict engineering properties such as tensile strength. The micro-model solidification kinetics can be evaluated using first principles or they can be evaluated using experiments. This work describes an implementation of a micro-model for uranium which uses experimental results to estimate nucleation and growth kinetics.

  11. Pressure slip casting of silicon nitride

    SciTech Connect

    Richter, H.J.

    1995-09-01

    This paper discusses the potential of pressure slip casting for components made of technical ceramic materials. The tests carried out on pressure slip casting and pressure filtration of silicon nitride show that the highest green density will be obtained if a slurry is used which is completely deflocculated and does not contain any binding agent. Penetration of fine particles into the porous plastic mould cannot be completely prevented but can be reduced to a large extent by the proper selection of the pressure-time regime.

  12. Caste-Selective Pheromone Biosynthesis in Honeybees

    NASA Astrophysics Data System (ADS)

    Plettner, Erika; Slessor, Keith N.; Winston, Mark L.; Oliver, James E.

    1996-03-01

    Queen and worker honeybees (Apis mellifera L.) produce a caste-related blend of functionalized 8- and 10-carbon fatty acids in their mandibular glands. The biological functions of these compounds match the queen's reproductive and the worker's nonreproductive roles in the colony. Studies with deuterated substrates revealed that the biosynthesis of these acids begins with stearic acid, which is hydroxylated at the 17th or 18th position. The 18-carbon hydroxy acid chains are shortened, and the resulting 10-carbon hydroxy acids are oxidized in a caste-selective manner, thereby determining many of the functional differences between queens and workers.

  13. Lymphoplasmacytic lymphoma causing light chain cast nephropathy.

    PubMed

    Pérez, Nuria S; Garcia-Herrera, Adriana; Rosiñol, Laura; Palos, Lily; Santiago, Evelyn; Espinosa, Gerard; Solé, Manel; Campistol, Josep M; Quintana, Luis F

    2012-01-01

    Plasma cell dyscrasias are frequently associated with kidney disease through the production of monoclonal immunoglobulin but with a diverse set of pathologic renal patterns. While almost all patients with a renal biopsy showing a cast nephropathy have myeloma, kidney involvement associated with pathological immunoglobulin light chains and lymphoma is rare. To our knowledge, this is the first report of a cast nephropathy associated with lymphoplasmacytic lymphoma. We emphasize the relation between light chain deposition and renal dysfunction in this disease with production of light chains. A therapeutic approach that decreases light chain production appears to be warranted in these patients. PMID:22241794

  14. Fluxing agent for metal cast joining

    DOEpatents

    Gunkel, Ronald W. (Lower Burrell, PA); Podey, Larry L. (Greensburg, PA); Meyer, Thomas N. (Murrysville, PA)

    2002-11-05

    A method of joining an aluminum cast member to an aluminum component. The method includes the steps of coating a surface of an aluminum component with flux comprising cesium fluoride, placing the flux coated component in a mold, filling the mold with molten aluminum alloy, and allowing the molten aluminum alloy to solidify thereby joining a cast member to the aluminum component. The flux preferably includes aluminum fluoride and alumina. A particularly preferred flux includes about 60 wt. % CsF, about 30 wt. % AlF.sub.3, and about 10 wt. % Al.sub.2 O.sub.3.

  15. Optimal design applications in casting and welding

    SciTech Connect

    Byrne, P.E.; Michaleris, P.; Tortorelli, D.A.; Dantzig, J.A.

    1995-12-31

    In this article, the authors couple design sensitivity analysis and numerical optimization with process simulation to improve the design of castings and weldments. They first derive expressions for explicit sensitivity analysis of weakly coupled thermal stress systems. In the first of two example problems thermal analysis is used to determine an optimal riser design for a steel hammer casting. In the second example, thermal and elasto-plastic stress analyses are performed on a butt-welding process, which is then optimized to control residual stress and distortion.

  16. INTERIOR VIEW WITH LARGE PIPE CASTING MACHINE EXTRACTING A 48' ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR VIEW WITH LARGE PIPE CASTING MACHINE EXTRACTING A 48' PIPE. - United States Pipe & Foundry Company Plant, Pipe Casting & Testing Area, 2023 St. Louis Avenue at I-20/59, Bessemer, Jefferson County, AL

  17. INTERIOR VIEW WITH PIPE CASTING MACHINE EXTRUDING A 24' PIPE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR VIEW WITH PIPE CASTING MACHINE EXTRUDING A 24' PIPE AND OPERATOR JOHNNY NIXON. - United States Pipe & Foundry Company Plant, Pipe Casting & Testing Area, 2023 St. Louis Avenue at I-20/59, Bessemer, Jefferson County, AL

  18. Molding procedure for casting a variety of alloys

    NASA Technical Reports Server (NTRS)

    Fontes, M. J.; Kourtides, D.; Leibfritz, E. R.

    1970-01-01

    General procedure and molding sand composition for preparing molds usable for casting variety of alloys are developed. Molds are prepared from mixture of sand, sodium silicate binder, and organic liquid ester. Castings of radiographic quality are produced from various alloys.

  19. FINISHED CASTINGS ARE ONLY GROUND BEFORE THEY ARE SHIPPED TO ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    FINISHED CASTINGS ARE ONLY GROUND BEFORE THEY ARE SHIPPED TO CUSTOMERS WHO COMPLETE THE FINISHING IN THEIR OWN MACHINE SHOPS. - Southern Ductile Casting Company, Grinding & Shipping, 2217 Carolina Avenue, Bessemer, Jefferson County, AL

  20. SOUTHERN DUCTILE CASTING COMPANY, BACK SIDE OF FURNACE AND MOLDING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    SOUTHERN DUCTILE CASTING COMPANY, BACK SIDE OF FURNACE AND MOLDING BUILDINGS SHOWING CONNECTIONS TO LOCAL POWER GRID, PRIMARILY FOR ELECTRIC FURNACES. - Southern Ductile Casting Company, Bessemer Foundry, 2217 Carolina Avenue, Bessemer, Jefferson County, AL

  1. Prediction of porosity in cast equiaxed alloy 718

    SciTech Connect

    Ko, Y.K.; Sahai, V.; Overfelt, R.A.; Berry, J.T.

    1995-12-31

    The prediction of porosity distribution in shaped castings is a popular topic at the present time. A number of criteria functions (CFs) have been proposed to assist in such predictions, these functions generally being obtained from computer modeling of solidification. Although considerable attention has been given to the use of CFs with plain carbon steel and aluminum castings, only limited attention has been given to superalloy castings. Using experimental data on porosity distribution in such castings for validation, various criteria functions were compared for effectiveness in predicting the level of porosity in castings of different thicknesses vacuum investment cast in alloy 718. The criteria functions concerned were obtained by interrogating the output of a simulation using commercially available software. The castings were in the form of vertically cast plates attached to a common top gating system. The problems associated with obtaining thermally accurate simulation, as well as appropriate validation are also discussed.

  2. OVERVIEW LOOKING SOUTH OF CONTAINMENT SYSTEM (TOP), SLAB CASTING MACHINE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    OVERVIEW LOOKING SOUTH OF CONTAINMENT SYSTEM (TOP), SLAB CASTING MACHINE AND RUN OUT WITH TRAVELING TORCH. MACHINE IS CASTING IN TWIN MOLD. - U.S. Steel, Fairfield Works, Continuous Caster, Fairfield, Jefferson County, AL

  3. 19. Inside the cast house at Furnace A. Molten iron ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    19. Inside the cast house at Furnace A. Molten iron flowed into eight ladles. The furnace was cast (or tapped) six times each day. - Central Furnaces, 2650 Broadway, east bank of Cuyahoga River, Cleveland, Cuyahoga County, OH

  4. MALLEABLE INSPECTION STATION WHERE WORKERS ELIMINATE MALFORMED CASTINGS AND SEPARATED ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    MALLEABLE INSPECTION STATION WHERE WORKERS ELIMINATE MALFORMED CASTINGS AND SEPARATED GOOD CASTINGS PRIOR TO ANNEALING. - Stockham Pipe & Fittings Company, Malleable Annealing Building, 4000 Tenth Avenue North, Birmingham, Jefferson County, AL

  5. Accuracy of successive casts for full-arch fixed prostheses.

    PubMed

    Dounis, Kiki S; Dounis, Georgia; Ditmyer, Marcia M; Ziebert, Gerald J

    2010-01-01

    This clinically simulated study examined the accuracy of full-arch impression materials using successive casts reproduced from single impressions. Materials tested included a polyether polyvinyl siloxane, medium viscosity material, and putty wash. Maxillary full-arch Dentoform models were created with four abutments prepared for complete crowns. Six impressions of each material produced successive first and second generation casts. Individual cast copings were then fabricated and assembled into full-arch fixed dental prostheses. Marginal discrepancies were measured on both the casts and Dentoform. Data analysis suggests insignificant differences between successive casts. However, among second generation casts, clinically similar marginal discrepancies were exhibited. Outcomes demonstrated that second generation casts enabled fabrication and assembly of full-arch restorations that were clinically equivalent to first generation casts obtained. PMID:20859561

  6. Enhancements in Magnesium Die Casting Impact Properties

    SciTech Connect

    David Schwam; John F. Wallace; Yulong Zhu; Srinath Viswanathan; Shafik Iskander

    2000-06-30

    The need to produce lighter components in transportation equipment is the main driver in the increasing demand for magnesium castings. In many automotive applications, components can be made of magnesium or aluminum. While being lighter, often times the magnesium parts have lower impact and fatigue properties than the aluminum. The main objective of this study was to identify potential improvements in the impact resistance of magnesium alloys. The most common magnesium alloys in automotive applications are AZ91D, AM50 and AM60. Accordingly, these alloys were selected as the main candidates for the study. Experimental quantities of these alloys were melted in an electrical furnace under a protective atmosphere comprising sulfur hexafluoride, carbon dioxide and dry air. The alloys were cast both in a permanent mold and in a UBE 315 Ton squeeze caster. Extensive evaluation of tensile, impact and fatigue properties was conducted at CWRU on permanent mold and squeeze cast test bars of AZ91, AM60 and AM50. Ultimate tensile strength values between 20ksi and 30ksi were obtained. The respective elongations varied between 25 and 115. the Charpy V-notch impact strength varied between 1.6 ft-lb and 5 ft-lb depending on the alloy and processing conditions. Preliminary bending fatigue evaluation indicates a fatigue limit of 11-12 ksi for AM50 and AM60. This is about 0.4 of the UTS, typical for these alloys. The microstructures of the cast specimens were investigated with optical and scanning electron microscopy. Concomitantly, a study of the fracture toughness in AM60 was conducted at ORNL as part of the study. The results are in line with values published in the literature and are representative of current state of the art in casting magnesium alloys. The experimental results confirm the strong relationship between aluminum content of the alloys and the mechanical properties, in particular the impact strength and the elongation. As the aluminum content increases from about 5% in AM50 to over 9% in AZ91, more of the intermetallic Mg17Al12 is formed in the microstructure. For instance, for 15 increase in the aluminum content from AM50 to AM60, the volume fraction of eutectic present in the microstructure increases by 35%! Eventually, the brittle Mg17Al12 compound forms an interconnected network that reduces ductility and impact resistance. The lower aluminum in AM50 and AM60 are therefore a desirable feature in applications that call for higher impact resistance. Further improvement in impact resistance depends on the processing condition of the casting. Sound castings without porosity and impurities will have better mechanical properties. Since magnesium oxidizes readily, good melting and metal transfer practices are essential. The liquid metal has to be protected from oxidation at all times and entrainment of oxide films in the casting needs to be prevented. In this regard, there is evidence that us of vacuum to evacuate air from the die casting cavity can improve the quality of the castings. Fast cooling rates, leading to smaller grain size are beneficial and promote superior mechanical properties. Micro-segregation and banding are two additional defect types often encountered in magnesium alloys, in particular in AZ91D. While difficult to eliminate, segregation can be minimized by careful thermal management of the dies and the shot sleeve. A major source of segregation is the premature solidification in the shot sleeve. The primary solid dendrites are carried into the casting and form a heterogeneous structure. Furthermore, during the shot, segregation banding can occur. The remedies for this kind of defects include a hotter shot sleeve, use of insulating coatings on the shot sleeve and a short lag time between pouring into the shot sleeve and the shot.

  7. Reinforcing a Spica Cast With a Fiberglass Bar.

    PubMed

    Chaudhry, Sonia; Kang, Kevin; Lee, Mark C

    2015-11-01

    Hip spica casting is used in the treatment of femur fractures and hip dysplasia in children 1 to 6 years old. A bar connecting the legs of the cast has been shown to improve cast integrity and assist in patient transport. We present a simple and low-cost technique that can be used to create a connecting bar and that can be performed with readily available casting materials. PMID:26566556

  8. Application of TRIZ Theory in Patternless Casting Manufacturing Technique

    NASA Astrophysics Data System (ADS)

    Yang, Weidong; Gan, Dequan; Jiang, Ping; Tian, Yumei

    The ultimate goal of Patternless Casting Manufacturing (referred to as PCM) is how to obtain the casts by casting the sand mold directly. In the previous PCM, the resin content of sand mold is much higher than that required by traditional resin sand, so the casts obtained are difficult to be sound and qualified products, which limits the application of this technique greatly. In this paper, the TRIZ algorithm is introduced to the innovation process in PCM systematically.

  9. 22 CFR 121.10 - Forgings, castings, and machined bodies.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 22 Foreign Relations 1 2014-04-01 2014-04-01 false Forgings, castings, and machined bodies. 121.10... STATES MUNITIONS LIST Enumeration of Articles 121.10 Forgings, castings, and machined bodies. The U.S. Munitions List controls as defense articles those forgings, castings, and other unfinished products, such...

  10. 27 CFR 447.22 - Forgings, castings, and machined bodies.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 3 2012-04-01 2010-04-01 true Forgings, castings, and... IMPLEMENTS OF WAR The U.S. Munitions Import List 447.22 Forgings, castings, and machined bodies. Articles..., castings, extrusions, and machined bodies) which have reached a stage in manufacture where they are...

  11. 27 CFR 447.22 - Forgings, castings, and machined bodies.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 3 2011-04-01 2010-04-01 true Forgings, castings, and... IMPLEMENTS OF WAR The U.S. Munitions Import List 447.22 Forgings, castings, and machined bodies. Articles..., castings, extrusions, and machined bodies) which have reached a stage in manufacture where they are...

  12. 25 CFR 217.6 - Method of casting votes.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Method of casting votes. 217.6 Section 217.6 Indians.... 217.6 Method of casting votes. Within 30 days after an issue and any analysis provided for in 217.4... superintendent in writing of the number of votes cast for and against the proposed or alternative solutions....

  13. 29 CFR 452.131 - Casting of ballots; delegate elections.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 2 2012-07-01 2012-07-01 false Casting of ballots; delegate elections. 452.131 Section 452... REPORTING AND DISCLOSURE ACT OF 1959 Election Procedures; Rights of Members 452.131 Casting of ballots; delegate elections. The manner in which the votes of the representatives are cast in the convention is...

  14. 46 CFR 153.239 - Use of cast iron.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Use of cast iron. 153.239 Section 153.239 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SHIPS CARRYING BULK... Systems 153.239 Use of cast iron. (a) Cast iron used in a cargo containment system must meet...

  15. 25 CFR 217.6 - Method of casting votes.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 25 Indians 1 2012-04-01 2011-04-01 true Method of casting votes. 217.6 Section 217.6 Indians.... 217.6 Method of casting votes. Within 30 days after an issue and any analysis provided for in 217.4... superintendent in writing of the number of votes cast for and against the proposed or alternative solutions....

  16. 42 CFR 414.106 - Splints and casts.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 3 2014-10-01 2014-10-01 false Splints and casts. 414.106 Section 414.106 Public... Parenteral and Enteral Nutrition (PEN) Nutrients, Equipment and Supplies, Splints, Casts, and Certain Intraocular Lenses (IOLs) 414.106 Splints and casts. (a) Payment rules. Payment is made in a lump sum...

  17. 29 CFR 452.131 - Casting of ballots; delegate elections.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 2 2014-07-01 2014-07-01 false Casting of ballots; delegate elections. 452.131 Section 452... REPORTING AND DISCLOSURE ACT OF 1959 Election Procedures; Rights of Members 452.131 Casting of ballots; delegate elections. The manner in which the votes of the representatives are cast in the convention is...

  18. 29 CFR 452.131 - Casting of ballots; delegate elections.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 2 2013-07-01 2013-07-01 false Casting of ballots; delegate elections. 452.131 Section 452... REPORTING AND DISCLOSURE ACT OF 1959 Election Procedures; Rights of Members 452.131 Casting of ballots; delegate elections. The manner in which the votes of the representatives are cast in the convention is...

  19. 46 CFR 153.239 - Use of cast iron.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false Use of cast iron. 153.239 Section 153.239 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SHIPS CARRYING BULK... Systems 153.239 Use of cast iron. (a) Cast iron used in a cargo containment system must meet...

  20. 46 CFR 153.239 - Use of cast iron.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 5 2012-10-01 2012-10-01 false Use of cast iron. 153.239 Section 153.239 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SHIPS CARRYING BULK... Systems 153.239 Use of cast iron. (a) Cast iron used in a cargo containment system must meet...

  1. 25 CFR 217.6 - Method of casting votes.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 25 Indians 1 2011-04-01 2011-04-01 false Method of casting votes. 217.6 Section 217.6 Indians.... 217.6 Method of casting votes. Within 30 days after an issue and any analysis provided for in 217.4... superintendent in writing of the number of votes cast for and against the proposed or alternative solutions....

  2. 22 CFR 121.10 - Forgings, castings and machined bodies.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 22 Foreign Relations 1 2013-04-01 2013-04-01 false Forgings, castings and machined bodies. 121.10... STATES MUNITIONS LIST Enumeration of Articles 121.10 Forgings, castings and machined bodies. Articles..., castings, extrusions and machined bodies) which have reached a stage in manufacture where they are...

  3. 27 CFR 447.22 - Forgings, castings, and machined bodies.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 3 2013-04-01 2013-04-01 false Forgings, castings, and... IMPLEMENTS OF WAR The U.S. Munitions Import List 447.22 Forgings, castings, and machined bodies. Articles..., castings, extrusions, and machined bodies) which have reached a stage in manufacture where they are...

  4. 29 CFR 452.131 - Casting of ballots; delegate elections.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 2 2011-07-01 2011-07-01 false Casting of ballots; delegate elections. 452.131 Section 452... REPORTING AND DISCLOSURE ACT OF 1959 Election Procedures; Rights of Members 452.131 Casting of ballots; delegate elections. The manner in which the votes of the representatives are cast in the convention is...

  5. 27 CFR 447.22 - Forgings, castings, and machined bodies.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 3 2014-04-01 2014-04-01 false Forgings, castings, and... IMPLEMENTS OF WAR The U.S. Munitions Import List 447.22 Forgings, castings, and machined bodies. Articles..., castings, extrusions, and machined bodies) which have reached a stage in manufacture where they are...

  6. 25 CFR 217.6 - Method of casting votes.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 25 Indians 1 2014-04-01 2014-04-01 false Method of casting votes. 217.6 Section 217.6 Indians.... 217.6 Method of casting votes. Within 30 days after an issue and any analysis provided for in 217.4... superintendent in writing of the number of votes cast for and against the proposed or alternative solutions....

  7. INTERIOR VIEW WITH PIPE CASTING MACHINE WITH OPERATOR JOHNNY NIXON ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR VIEW WITH PIPE CASTING MACHINE WITH OPERATOR JOHNNY NIXON SETTING A CORE IN THE CASTING OF A 24' PIPE. - United States Pipe & Foundry Company Plant, Pipe Casting & Testing Area, 2023 St. Louis Avenue at I-20/59, Bessemer, Jefferson County, AL

  8. 22 CFR 121.10 - Forgings, castings and machined bodies.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 22 Foreign Relations 1 2012-04-01 2012-04-01 false Forgings, castings and machined bodies. 121.10... STATES MUNITIONS LIST Enumeration of Articles 121.10 Forgings, castings and machined bodies. Articles..., castings, extrusions and machined bodies) which have reached a stage in manufacture where they are...

  9. 29 CFR 452.131 - Casting of ballots; delegate elections.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 2 2010-07-01 2010-07-01 false Casting of ballots; delegate elections. 452.131 Section 452... REPORTING AND DISCLOSURE ACT OF 1959 Election Procedures; Rights of Members 452.131 Casting of ballots; delegate elections. The manner in which the votes of the representatives are cast in the convention is...

  10. 25 CFR 217.6 - Method of casting votes.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 25 Indians 1 2013-04-01 2013-04-01 false Method of casting votes. 217.6 Section 217.6 Indians.... 217.6 Method of casting votes. Within 30 days after an issue and any analysis provided for in 217.4... superintendent in writing of the number of votes cast for and against the proposed or alternative solutions....

  11. Clean Cast Steel Technology - Machinability and Technology Transfer

    SciTech Connect

    C. E. Bates; J. A. Griffin

    2000-05-01

    There were two main tasks in the Clean Cast Steel Technology - Machinability and Technology Transfer Project. These were (1) determine the processing facts that control the machinability of cast steel and (2) determine the ability of ladle stirring to homogenize ladle temperature, reduce the tap and pouring temperatures, and reduce casting scrap.

  12. New methods and materials for molding and casting ice formations

    NASA Technical Reports Server (NTRS)

    Reehorst, Andrew L.; Richter, G. Paul

    1987-01-01

    This study was designed to find improved materials and techniques for molding and casting natural or simulated ice shapes that could replace the wax and plaster method. By utilizing modern molding and casting materials and techniques, a new methodology was developed that provides excellent reproduction, low-temperature capability, and reasonable turnaround time. The resulting casts are accurate and tough.

  13. 46 CFR 153.239 - Use of cast iron.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Use of cast iron. 153.239 Section 153.239 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SHIPS CARRYING BULK... Systems 153.239 Use of cast iron. (a) Cast iron used in a cargo containment system must meet...

  14. 46 CFR 153.239 - Use of cast iron.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Use of cast iron. 153.239 Section 153.239 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SHIPS CARRYING BULK... Systems 153.239 Use of cast iron. (a) Cast iron used in a cargo containment system must meet...

  15. The effect on cast post dimensions of casting investment and airborne particle abrasion.

    PubMed

    Hashem, Danya; German, Matthew J; Wassell, Robert W

    2011-09-01

    Cast posts can sometimes prove difficult to seat fully during fitting. This study compared two different liquid/water dilutions for phosphate bonded investment and the effect of controlled airborne particle abrasion on resulting post diameter. After measuring polymeric post patterns (n = 18), 3 groups were invested using concentrated solution and 3 groups using dilute solution. After casting they were weighed and remeasured then exposed to airborne particle abrasion. Both solutions produced oversized cast posts. Mean diameter reduction during airborne particle abrasion was 8 microm/10s taking an average of 41s to reach precast size. Where a post pattern fits tightly, airborne particle abrasion for 70s should reduce the casting sufficiently to accommodate the cement lute. PMID:22645794

  16. Casting the Spirit: A Handmade Legacy

    ERIC Educational Resources Information Center

    Rutenberg, Mona

    2008-01-01

    This article discusses how an art therapist working in a hospital palliative care unit has incorporated a ritual of hand casting to help bring closure to dying patients and family members who are grieving as death approaches. The finished hand sculptures depict the hands of the patients and, sometimes, of their loved ones. They are faithful and

  17. Roll Casting of Al-25%Si

    NASA Astrophysics Data System (ADS)

    Haga, Toshio; Harada, Hideto; Watari, Hisaki

    2011-05-01

    Strip casting of Al-25%Si strip was tried using an unequal diameter twin roll caster. The diameter of the lower roll (large roll) was 1000 mm and the diameter of the upper roll (small roll) was 250 mm. Roll material was mild steel. The sound strip could be cast at the speeds ranging from 8 m/min to 12 m/min. The strip did not stick to the roll without the parting material. The primary Si, which existed at centre area of the thickness direction, was larger than that which existed at other area. The size of the primary Si was smaller than 0.2 mm. Eutectic Si was smaller 5 ?m. The as-cast strip was ranging from 2 mm to 3 mm thick and its width was 100 mm. The as-cast strip could be hot rolled down to 1 mm. The hot rolled strip was cold rolled. The primary Si became smaller and the pore occurred around the primary Si after the rolling.

  18. Modal Vibration Analysis of Large Castings

    NASA Technical Reports Server (NTRS)

    Werlink, Rudolph J.; Margasahayam, Ravi N.

    2009-01-01

    The art of experimental modal vibration analysis (MVA) has been extended to apply to large castings. This extension was made to enable the use of experimental MVA as a relatively inexpensive, simple means of assessing the internal structural integrity of tread shoes of crawler transporters used to move spacecraft to the launch pad at Kennedy Space Center. Each tread shoe is made from cast iron and weighs about a ton (has a mass .907 kg). The present extended version of experimental MVA could also be applied to other large castings. It could be especially useful to manufacturers as a means of rapidly discriminating against large castings that contain unacceptably large concentrations of internal defects. The use of experimental MVA to assess structural integrity is not new. What are new here are those aspects of the extension of experimental MVA that pertain to the application of MVA to objects so massive that it may not be practical or cost effective to mount them in special test fixtures that impose special test boundary conditions to test them in place under normal conditions of use.

  19. Oriented growth of cast silicon sheets

    NASA Astrophysics Data System (ADS)

    Saito, T.; Shimura, A.; Matsui, J.

    1985-09-01

    Casting of silicon sheets in molds, using a mold releasing agent, is shown to result in the attainment of a large size columnar grain structure normal to the sheet surface, and a predominantly 110 surface orientation. A possible oriented growth mechanism is proposed on the basis of dendritic grain growth.

  20. Arsenic Removal from Drinking Water - Web cast

    EPA Science Inventory

    Web cast presentation covered six topics: (1) Arsenic Chemistry, (2) Technology Selection/Arsenic Demonstration Program, (3) Case Study 1, (4) Caser Study 2, (5) Case Study 3, and (6) Media Regeneration Project. The presentation was considered a training session and consist of m...

  1. Gelcasting Alumina Cores for Investment Casting

    SciTech Connect

    Janney, M A; Klug, F J

    2001-01-01

    General Electric currently uses silica investment casting cores for making superalloy turbine blades. The silica core technology does not provide the degree of dimensional control needed for advanced turbine system manufacture. The sum of the various process variables in silica core manufacturing produces cores that have more variability than is allowed for in advanced, power-generation gas turbine airfoils.

  2. Feature Analysis of ToxCast Compounds

    EPA Science Inventory

    ToxCast was initiated by the US Environmental Protection Agency (EPA) to prioritize environmental chemicals for toxicity testing. Phase I generated data for 309 unique chemicals, mostly pesticide actives, that span diverse chemical feature/property space, as determined by quantu...

  3. Carburizer Effect on Cast Iron Solidification

    NASA Astrophysics Data System (ADS)

    Janerka, Krzysztof; Kondracki, Marcin; Jezierski, Jan; Szajnar, Jan; Stawarz, Marcin

    2014-06-01

    This paper presents the effect of carburizing materials on cast iron solidification and crystallization. The studies consisted of cast iron preparation from steel scrap and different carburizers. For a comparison, pig iron was exclusively used in a solid charge. Crystallization analysis revealed the influence of the carburizer material on the crystallization curves as well as differences in the solidification paths of cast iron prepared with the use of different charge materials. The carburizers' influence on undercooling during the eutectic crystallization process was analyzed. The lowest undercooling rate was recorded for the melt with pig iron, then for synthetic graphite, natural graphite, anthracite, and petroleum coke (the highest undercooling rate). So a hypothesis was formulated that eutectic cells are created most effectively with the presence of carbon from pig iron (the highest nucleation potential), and then for the graphite materials (crystallographic similarity with the carbon precipitation in the cast iron). The most difficult eutectic crystallization is for anthracite and petroleum coke (higher undercooling is necessary). This knowledge can be crucial when the foundry plant is going to change the solid charge composition replacing the pig iron by steel scrap and the recarburization process.

  4. Cast Stainless Steel Ferrite and Grain Structure

    SciTech Connect

    Ruud, Clayton O.; Ramuhalli, Pradeep; Meyer, Ryan M.; Mathews, Royce; Diaz, Aaron A.; Anderson, Michael T.

    2012-09-01

    In-service inspection requirements dictate that piping welds in the primary pressure boundary of light-water reactors be subject to a volumetric examination based on the rules contained within the American Society of Mechanical Engineers Boiler and Pressure Vessel Code, Section XI. The purpose of the inspection is the reliable detection and accurate sizing of service-induced degradation and/or material flaws introduced during fabrication. The volumetric inspection is usually carried out using ultrasonic testing (UT) methods. However, the varied metallurgical macrostructures and microstructures of cast austenitic stainless steel piping and fittings, including statically cast stainless steel and centrifugally cast stainless steel (CCSS), introduce significant variations in the propagation and attenuation of ultrasonic energy. These variations complicate interpretation of the UT responses and may compromise the reliability of UT inspection. A review of the literature indicated that a correlation may exist between the microstructure and the delta ferrite content of the casting alloy. This paper discusses the results of a recent study where the goal was to determine if a correlation existed between measured and/or calculated ferrite content and grain structure in CCSS pipe.

  5. Templates Aid Removal Of Defects From Castings

    NASA Technical Reports Server (NTRS)

    Hendrickson, Robert G.

    1992-01-01

    Templates used to correlate defects in castings with local wall thicknesses. Placed on part to be inspected after coated with penetrant dye. Positions of colored spots (indicative of defects) noted. Ultrasonic inspector measures thickness of wall at unacceptable defects only - overall inspection not necessary.

  6. Cast Iron With High Carbon Content

    NASA Technical Reports Server (NTRS)

    Curreri, P. A.; Hendrix, J. C.; Stefanescu, D. M.

    1986-01-01

    Method proposed for solidifying high-carbon cast iron without carbon particles segregating at upper surface. Solidification carried out in low gravity, for example on airplane flying free-fall parabolic trajectory. Many different microstructures obtained by proposed technique, and percentage by weight of carbon retained in melt much higher than at present.

  7. Graphite formation in cast iron, phase 2

    NASA Technical Reports Server (NTRS)

    Stefanescu, D. M.; Fiske, M. R.

    1985-01-01

    Several types of cast irons are directionally solidified aboard the KC-135 aircraft. Also, control samples are run on Earth for comparison. Some of these samples are unusable because of various mechanical problems; the analysis and the interpretation of results on the samples that are run successfully is discussed.

  8. An Update on ToxCast

    EPA Science Inventory

    In its first phase, ToxCast is profiling over 300 well-characterized chemicals (primarily pesticides) in over 400 HTS endpoints. These endpoints include biochemical assays of protein function, cell-based transcriptional reporter assays, multi-cell interaction assays, transcripto...

  9. An Introduction to ToxCast

    EPA Science Inventory

    ToxCast is a chemical prioritization research program to develop the ability to forecast toxicity using bioactivity profiling. The point is to use results in a variety of in vitro and rapid non-mammalian in vivo assays to explore effects at different toxicity targets. The desi...

  10. Thermal Modelling In Pressure Die Casting

    NASA Astrophysics Data System (ADS)

    Rasgado, M. T. Alonso; Davey, K.; Watari, H.

    2004-06-01

    The pressure die casting process is cyclic and the temperature levels in the die are principally dictated by the total energy received from the casting. It is thus extremely important that any solidification model for the casting is able to predict energy extraction rates to a high degree of accuracy. In this paper an efficient three dimensional hybrid thermal model for the pressure die casting process is described. The finite element method (FEM) is used for modelling heat transfer in the casting, coupled to a boundary element (BE) model for the die. The FEM can efficiently account for the non-linearity introduced by the release of latent heat on solidification, whereas the BEM is ideally suited for modelling linear heat conduction in the die, as surface temperatures are of principal importance. The FE formulation for the casting is based on a control volume capacitance method, which is shown to provide high accuracy and stability. This method is similar to the apparent and effective heat capacitance methods, which are popular approaches used where conduction predominates over other heat transfer mechanisms. These methods involve the specification of element or nodal capacitances to accommodate for the release of latent heat. Unfortunately they suffer from a major drawback in that energy is not correctly transported through elements and so providing a source of inaccuracy. The control volume capacitance method allows for the transport of mass arising from volumetric shrinkage and ensures that energy is correctly transported. The BE model caters for surface phenomena such as boiling in the cooling channels, which is important, as this effectively controls the manner in which energy is extracted. The die temperature is decomposed into two components, one a steady-state part and the other a time-dependent perturbation. This approach enables the transient die temperatures to be calculated in an efficient way, since only die surfaces close to the die cavity are considered in the perturbation analysis. The governing equations across domains are coupled by means of a multiplicative-Schwarz method for non-overlapping domains as focus is on the use of serial processing. A coarse preconditioner is utilised and obtained from a crude representation of the global system of equations. Numerical experiments are performed to demonstrate the computational effectiveness of the approach. Predicted die and casting temperatures are compared with thermocouple measurements and good agreement is indicated.

  11. A new freeze casting technique for ceramics

    NASA Astrophysics Data System (ADS)

    Araki, Kiyoshi

    A new freeze casting technique for ceramics capable of manufacturing near room temperature with a sublimable vehicle has been developed in order to eliminate expensive processes under extremely cold temperatures in the conventional freeze casting. Fluid concentrated slurries of Al2O 3 powder in molten camphene (C10H16) were successfully prepared at 55°C with a small amount of a dispersant. These slurries were quickly solidified (frozen) at room temperature to yield a rigid solid green body, where the frozen camphene was easily removed by sublimation (freeze-drying) with negligible shrinkage. Sintering was successfully conducted without any special binder burnout process to yield dense sintered bodies (over 98% T.D). An organic alloy with a eutectic composition in the naphthalene (C 10H8)-camphor (C10H16O) binary system with a eutectic temperature of 31°C was also found to be a successful vehicle for the new ceramic freeze casting. The fabrication processes are almost the same as those with camphene. It was found that vehicles with off-eutectic compositions resulted in large voids in the sintered body due to the ceramic particle rejection by pro-eutectic crystals during freezing. At the eutectic composition, fine lamellar microstructure in the solidified vehicle inhibits the particle rejection. The proposed advantages of the new freeze casting technique with a sublimable vehicle include; (1) elimination of extremely cold temperatures used in conventional freeze casting; (2) elimination of troublesome binder burnout process; and (3) fast manufacturing cycle due to quick solidification. Porous ceramic bodies with unique interconnected pore channels were fabricated by the new freeze casting with lower solid content. The unique channels surrounded by fully dense walls have nearly circular cross-sections unlike conventional aqueous freeze casting. The porosity and the channel diameters are controllable by the solid content in the slurry. The unique channels are replicas of entangled dendrites of frozen camphene, which sublimes during freeze-drying process. The unique porous structure with interconnected pore channels, which is completely new, is considered potentially useful in many applications such as filters and implantable bone scaffolds.

  12. Viability changes: Microbiological analysis of dental casts

    PubMed Central

    ilinskas, Juozas; Junevi?ius, Jonas; Ramonait?, Agn?; Pavilonis, Alvydas; Gleiznys, Alvydas; Sakalauskien?, Jurgina

    2014-01-01

    Background This study evaluated the survival of the most prevalent oral bacteria and fungi (Staphylococcus aureus, Klebsiella pneumoniae, Escherichia coli, and Candida albicans) in dental casts, and compared changes in the amounts of these microorganisms at different time intervals to determine how long dental casts may pose threat to the health of dental personnel and patients. Material/Methods When manufacturing the casts, regular water was replaced with sterile distilled water, where suspensions of the studied bacteria or the fungus at certain concentrations were prepared. When the dental casts were fully set (solidified), plaster shavings were examined immediately after the contact of the studied microorganism with the plaster, as well as after 1, 2, 24, 48, 72, 96, and 120 hours. Following that, we measured how the amount of the studied bacteria and fungi in 1 gram of the plaster changed within the studied period of time. Results Klebsiella pneumoniae survived in plaster for up to 4 days, and the reduction in the number of these bacteria became statistically significant after 1 day (p<0.05). Staphylococcus aureus remained viable in plaster for up to 4 days, and the number of these bacteria dropped after 1 day (p<0.05). Escherichia coli disappeared after 2 days, and a reduction was already observed after 2 hours (p<0.05). Candida albicans in plaster models died within 2 days, and a reduction in their number was observed after 1 day (p<0.05). Conclusions The microorganisms did not multiply in the gypsum casts and their number significantly dropped instead of increasing. PMID:24902637

  13. A Modified Cast-on Method for the Reinforcement of Aluminum Castings with Dissimilar Metals

    NASA Astrophysics Data System (ADS)

    Han, Qingyou

    2016-02-01

    A modified cast-on method has been developed to reinforce aluminum castings with steel insert. Defect-free bond between the steel insert and the aluminum casting has been consistently obtained. Data obtained from a push-out experiment indicated that the bond strength was much higher than that obtained using the Al-Fin approach. This paper introduces this modified method in four sections: the coating of the steel pins, the cast-on method, microstructure characterization, and the bond strength. The section on the coating of the steel pins contains coating material selection, electroplating technique for plating Cu and Ni on steel, and diffusion bonding of the coatings to the steel. The section on cast-on method deals with factors that affecting the quality of the metallurgical bond between the coated steel and the aluminum castings. The results of microstructure characteristics of the bonding are presented in the microstructure characterization section. A push-out experiment and the results obtained using this method is described in the section of bond strength/mechanical property.

  14. Relationship between casting modulus and grain size in cast A356 aluminium alloys

    NASA Astrophysics Data System (ADS)

    Niklas, A.; Abaunza, U.; Fernndez-Calvo, A. I.; Lacaze, J.

    2012-01-01

    Microstructure of Al-Si alloy castings depends most generally on melt preparation and on the cooling rate imposed by the thermal modulus of the component. In the case of Al-Si alloys, emphasis is put during melt preparation on refinement of pro-eutectic (Al) grains and on modification of the Al-Si eutectic. Thermal analysis has been used since long to check melt preparation before casting, i.e. by analysis of the cooling curve during solidification of a sample cast in an instrumented cup. The conclusions drawn from such analysis are however valid for the particular cooling conditions of the cups. It thus appeared of interest to investigate how these conclusions could extrapolate to predict microstructure in complicated cast parts showing local changes in the solidification conditions. For that purpose, thermal analysis cups and instrumented sand and die castings with different thermal moduli and thus cooling rates have been made, and the whole set of cooling curves thus recorded has been analysed. A statistical analysis of the characteristic features of the cooling curves related to grain refinement in sand and die castings allowed determining the most significant parameters and expressing the cube of grain size as a polynomial of these parameters. After introduction of a further parameter quantifying melt refining an excellent correlation, with a R2 factor of 0.99 was obtained.

  15. Characterization of Bimetallic Castings with an Austenitic Working Surface Layer and an Unalloyed Cast Steel Base

    NASA Astrophysics Data System (ADS)

    Wrbel, Tomasz

    2014-05-01

    The paper presents the technology of bimetallic castings based on the founding method of layer coating directly in the cast process of the so-called method of mold cavity preparation. The prepared castings consist of two fundamental parts, i.e., the base and the working surface layer. The base part of the bimetallic casting is typical foundry material, i.e., unalloyed cast steel, whereas the working layer is a plate of austenitic alloy steel sort X2CrNi 18-9. The quality of the joint between the base part and the working layer was evaluated on the basis of ultrasonic non-destructive testing and structure examinations containing metallographic macro- and microscopic studies with the use of a light microscope (LOM) with microhardness measurements and a scanning electron microscope (SEM) with microanalysis of the chemical composition (energy dispersive spectroscopyEDS). On the basis of the obtained results it was confirmed that the decisive phenomena needed to create a permanent joint between the two components of the bimetallic casting are carbon and heat transport in the direction from the high-carbon and hot base material which was poured into the mold in the form of liquid metal to the low-carbon and cold material of the working layer which was placed in the mold cavity in the form of a monolithic insert.

  16. Caste in 21st Century India: Competing Narratives

    PubMed Central

    Desai, Sonalde; Dubey, Amaresh

    2012-01-01

    Recent debates regarding inclusion of caste in 2011 Census have raised questions about whether caste still matters in modern India. Ethnographic studies of the mid-20th century identified a variety of dimensions along which caste differentiation occurs. At the same time, whether this differentiation translates into hierarchy remains a contentious issue as does the persistence of caste, given the economic changes of the past two decades. Using data from a nationally representative survey of 41,554 households conducted in 2005, this paper examines the relationship between social background and different dimensions of well-being. The results suggest continued persistence of caste disparities in education, income and social networks. PMID:22736803

  17. Method of making an apertured casting. [using duplicate mold

    NASA Technical Reports Server (NTRS)

    Terray, A. (inventor)

    1976-01-01

    An apertured casting is made by first forming a duplicate in the shape of the finished casting, positioning refractory metal bodies such as wires in the duplicate at points corresponding to apertures or passageways in finished products, forming a ceramic coating on the duplicate, removing the duplicate material, firing the ceramic in a vacuum or inert atmosphere, vacuum casting the metal in the ceramic form, removing the ceramic form, heating the cast object in an atmospheric furnace to oxidize the refractory metal bodies and then leaching the oxidized refractory bodies from the casting with a molten caustic agent or acid solution.

  18. Microstructure and Elemental Distribution in a Cast Austenitic Steel

    SciTech Connect

    Kenik, Edward A; Busby, Jeremy T; Hoelzer, David T; Rowcliffe, Arthur Frederick; Vitek, John Michael

    2007-01-01

    Casting of austenitic stainless steels offers the possibility of directly producing large and/or complex structures, such as the first wall shield module or the diverter cassette for the International Tokomak Experimental Reactor. However, the resulting mechanical properties and the corrosion resistance of such cast components can be inferior compared to conventionally forged components because of the larger grain size, lower dislocation density and extensive segregation inherent in the cast material. This study examines the microstructural and compositional heterogeneities of a large casting of 316N stainless steel, as well as the possibility of improving the homogeneity and mechanical properties of such a cast material.

  19. Experimentation and simulation of gravity fed lead castings

    SciTech Connect

    Korzekwa, D.R.; Lewis, M.A.K.; Rollett, A.D.; Erickson, W.C.; Bryant, L. Jr.

    1992-01-01

    Gravity fed load castings are analyzed both experimentally and numerically. Castings produced from various mold designs and crucible pour hole sizes are studied with Flash X-Ray Radiography to look at the mold filling and casting integrity. The same castings were also modeled using the commercial code FLOW-3D. Details of the fluid flow and the final structure are studied for both the experimental and numerical castings. This work also qualitatively compares flash x-ray radiographs with the simulations. FLOW-3D is in good agreement with the experimental work.

  20. Biliary casts after liver transplantation: Morphology and biochemical analysis

    PubMed Central

    Yang, Yu-Long; Zhang, Cheng; Lin, Mei-Ju; Shi, Li-Jun; Zhang, Hong-Wei; Li, Jing-Yi; Yu, Qiang

    2013-01-01

    AIM: To investigate the pathogenesis of biliary casts after liver transplantation relative to their morphology and biochemical markers. METHODS: The microstructure of biliary casts was assessed using scanning electron microscopy and Hematoxylin and eosin staining assessed their histology. The expression levels of CD3, CD5, CD34, CD68 and CD79a in these biliary casts were evaluated immunohistochemically. RESULTS: Biliary casts differed widely in their microstructure, with some containing blood vessels positive for CD34 and collagen fibers with positive Masson staining. Large numbers of neutrophils and other inflammatory cells were present, but only on the edge of the biliary casts; although the boundaries were clear without crossover. None of the biliary casts contained T-lymphocytes, B-lymphocytes, macrophages and other inflammatory cells. CONCLUSION: The microcostructure of biliary casts differed. Bacteria and acute rejection are not clearly related to their formation. PMID:24282366

  1. An investigation of squeeze-cast alloy 718

    NASA Technical Reports Server (NTRS)

    Gamwell, W. R.

    1993-01-01

    Alloy 718 billets produced by the squeeze-cast process have been evaluated for use as potential replacements for propulsion engine components which are normally produced from forgings. Alloy 718 billets were produced using various processing conditions. Structural characterizations were performed on 'as-cast' billets. As-cast billets were then homogenized and solution treated and aged according to conventional heat-treatment practices for this alloy. Mechanical property evaluations were performed on heat-treated billets. As-cast macrostructures and microstructures varied with squeeze-cast processing parameters. Mechanical properties varied with squeeze-cast processing parameters and heat treatments. One billet exhibited a defect free, refined microstructure, with mechanical properties approaching those of wrought alloy 718 bar, confirming the feasibility of squeeze-casting alloy 718. However, further process optimization is required, and further structural and mechanical property improvements are expected with process optimization.

  2. Metallic Fuel Casting Development and Parameter Optimization Simulations

    SciTech Connect

    R.S. Fielding; J. Crapps; C. Unal; J.R. Kennedy

    2013-03-01

    One of the advantages of metallic fuel is the abilility to cast the fuel slugs to near net shape with little additional processing. However, the high aspect ratio of the fuel is not ideal for casting. EBR-II fuel was cast using counter gravity injection casting (CGIC) but, concerns have been raised concerning the feasibility of this process for americium bearing alloys. The Fuel Cycle Research and Development program has begun developing gravity casting techniques suitable for fuel production. Compared to CGIC gravity casting does not require a large heel that then is recycled, does not require application of a vacuum during melting, and is conducive to re-usable molds. Development has included fabrication of two separate benchscale, approximately 300 grams, systems. To shorten development time computer simulations have been used to ensure mold and crucible designs are feasible and to identify which fluid properties most affect casting behavior and therefore require more characterization.

  3. Die Casting Part Distortion: Prediction and Attenuation

    SciTech Connect

    Dr, R. Allen Miller

    2002-02-12

    The goal of this research was to predict the part deformation and residual stresses after ejection from the die and cooling to room temperature. A finite element model was built to achieve this goal and several modeling techniques were investigated throughout this research. Die-casting is a very complex process and the researchers are faced with a large number of hard to solve physical problems when modeling the process. Several assumptions are made in our simulation model. The first significant assumption is the instantaneous cavity filling. This means that the cavity filling stage is not considered in our model. Considering the cavity filling stage increases the modeling complexity as a result of different flow patterns. expected in the shot sleeve, gate, runner and different cavity features. The flow of gas from the cavity through the vents is another problem that is ignored in our model as a result of this assumption. Our second assumption is that the cast metal has uniform temperature distribution inside the cavity, at the starting point of simulation. This temperature is assumed to be over liquidus limit, i.e. the solid fraction is 0.0% of the cast metal. The third assumption is due to ABAQUS (commercial software used in this research) limitations. ABAQUS cannot deal with multi-phase models; therefore we use solid elements to define the casting instead of multi-phase (liquid/solid) elements. Liquid elements can carry the hydrostatic pressure from the shot sleeve and apply it on the cavity surfaces, while the solid elements do not have this capability. To compensate for this assumption we add the cavity pressure as a boundary condition and apply it on the cavity surface separately from the part. Another issue with this assumption is that, liquid casting can follow the cavity shape when it distorts. With the use of solid elements to represent the casting during its liquid state, it loses this capability to follow the cavity. Several techniques were tested to overcome this problem.

  4. [Infrared casting temperature control of the induction centrifuge casting exemplary in the non-precious dental alloy Wiron 88].

    PubMed

    Mller, W D; Lotz, J; Lange, K P; Altrichter, B

    1991-01-01

    A temperature-dependent, IR-controlled casting technology for the non-precious dental alloy Wiron 88 (Bego) is presented and compared with a traditional procedure. The new casting allows the production of cast objects with favourable and reproducible material properties. Compared with the commonly used technology hardness, grain size and susceptibility to corrosion could be reduced. Texture after casting was found to be homogeneous. The procedure presented meets the requirements for a modern casting technology and be adapted to older automatic casating devices. PMID:1816820

  5. Genetic Evidence on the Origins of Indian Caste Populations

    PubMed Central

    Bamshad, Michael; Kivisild, Toomas; Watkins, W. Scott; Dixon, Mary E.; Ricker, Chris E.; Rao, Baskara B.; Naidu, J. Mastan; Prasad, B.V. Ravi; Reddy, P. Govinda; Rasanayagam, Arani; Papiha, Surinder S.; Villems, Richard; Redd, Alan J.; Hammer, Michael F.; Nguyen, Son V.; Carroll, Marion L.; Batzer, Mark A.; Jorde, Lynn B.

    2001-01-01

    The origins and affinities of the ?1 billion people living on the subcontinent of India have long been contested. This is owing, in part, to the many different waves of immigrants that have influenced the genetic structure of India. In the most recent of these waves, Indo-European-speaking people from West Eurasia entered India from the Northwest and diffused throughout the subcontinent. They purportedly admixed with or displaced indigenous Dravidic-speaking populations. Subsequently they may have established the Hindu caste system and placed themselves primarily in castes of higher rank. To explore the impact of West Eurasians on contemporary Indian caste populations, we compared mtDNA (400 bp of hypervariable region 1 and 14 restriction site polymorphisms) and Y-chromosome (20 biallelic polymorphisms and 5 short tandem repeats) variation in ?265 males from eight castes of different rank to ?750 Africans, Asians, Europeans, and other Indians. For maternally inherited mtDNA, each caste is most similar to Asians. However, 20%30% of Indian mtDNA haplotypes belong to West Eurasian haplogroups, and the frequency of these haplotypes is proportional to caste rank, the highest frequency of West Eurasian haplotypes being found in the upper castes. In contrast, for paternally inherited Y-chromosome variation each caste is more similar to Europeans than to Asians. Moreover, the affinity to Europeans is proportionate to caste rank, the upper castes being most similar to Europeans, particularly East Europeans. These findings are consistent with greater West Eurasian male admixture with castes of higher rank. Nevertheless, the mitochondrial genome and the Y chromosome each represents only a single haploid locus and is more susceptible to large stochastic variation, bottlenecks, and selective sweeps. Thus, to increase the power of our analysis, we assayed 40 independent, biparentally inherited autosomal loci (1 LINE-1 and 39 Alu elements) in all of the caste and continental populations (?600 individuals). Analysis of these data demonstrated that the upper castes have a higher affinity to Europeans than to Asians, and the upper castes are significantly more similar to Europeans than are the lower castes. Collectively, all five datasets show a trend toward upper castes being more similar to Europeans, whereas lower castes are more similar to Asians. We conclude that Indian castes are most likely to be of proto-Asian origin with West Eurasian admixture resulting in rank-related and sex-specific differences in the genetic affinities of castes to Asians and Europeans. PMID:11381027

  6. Comparison of residual stresses in sand- and chill casting of ductile cast iron wind turbine main shafts

    NASA Astrophysics Data System (ADS)

    Sonne, M. R.; Frandsen, J. O.; Hattel, J. H.

    2015-06-01

    In this work, simulations of pouring, solidification and cooling, and residual stress evolution of sand and chill cast wind turbine main shafts is performed. The models are made in the commercial software MAGMAsoft. As expected, the cooling rate of the sand casting is shown to be much lower than for the chill casting, resulting in a very course microstructure. From the simulations the nodule count is found to be 17 nodules per mm2 and 159 nodules per mm2 for the sand and chill casting, respectively, in the critical region of the main bearing seat. This is verified from nodule counts performed on the real cast main shafts. Residual stress evaluations show an overall increase of the maximum principal stress field for the chill casting, which is expected. However, the stresses are found to be in compression on the surface of the chill cast main shaft, which is unforeseen.

  7. Volatile species retention during metallic fuel casting

    NASA Astrophysics Data System (ADS)

    Fielding, Randall S.; Porter, Douglas L.

    2013-10-01

    Metallic nuclear fuels are candidate transmutation fuel forms for advanced fuel cycles. Through the operation of the Experimental Breeder Reactor II metallic nuclear fuels have been shown to be robust and easily manufactured. However, concerns have been raised concerning loss of americium during the casting process because of its high vapor pressure. In order to address these concerns a gaseous diffusion model was developed and a series of experiments using both manganese and samarium as surrogates for americium were conducted. The modeling results showed that volatility losses can be controlled to essentially no losses with a modest overpressure. Experimental results also showed volatile species retention down to no detectable losses through overpressure, and although the loss values varied from the model results the same trend was seen. Based on these results it is very probable that americium losses through volatility can be controlled to no detectable losses through application of a modest overpressure during casting.

  8. Process for slip casting textured tubular structures

    DOEpatents

    Steinlage, Greg A. (West Lafayette, IN); Trumble, Kevin P. (West Lafayette, IN); Bowman, Keith J. (West Lafayette, IN)

    2002-01-01

    A process for centrifugal slip casting a textured hollow tube. A slip made up of a carrier fluid and a suspended powder is introduced into a porous mold which is rotated at a speed sufficient to create a centrifugal force that forces the slip radially outward toward the inner surface of the mold. The suspended powder, which is formed of particles having large dimensional aspect ratios such as particles of superconductive BSCCO, settles in a textured fashion radially outward toward the mold surface. The carrier fluid of the slip passes by capillary action radially outward around the settled particles and into the absorbent mold. A layer of mold release material is preferably centrifugally slip cast to cover the mold inner surface prior to the introduction of the BSCCO slip, and the mold release layer facilitates removal of the BSCCO greenbody from the mold without fracturing.

  9. Integrating shadow casting methodology and thermal simulation

    SciTech Connect

    Malkawi, A.; Jabi, W.

    1996-10-01

    This paper describes an experiment that integrates shadow casting methodology and thermal simulation algorithms developed by the authors. The 3D shadow procedures use a polyhedral representation of solids within a Cartesian space that allows for accurate casting of shadows. The algorithm is also capable of calculating surface areas of polygonal shadows of any arbitrary shape and size. The thermal simulation algorithms--using the Transfer Function Method (TFM)--incorporate the shaded area calculations to better predict solar heat gain from glazing based on transmitted, absorbed, and conducted cooling loads. The paper describes the use of a 3D computer model to illustrate the impact of the pattern and area of shading on the visual and thermal properties of building apertures. The paper discusses the objectives of this experiment, the algorithms used, and their integration. Conclusions and findings are drawn.

  10. Phase Transformation in Cast Superaustenitic Stainless Steels

    SciTech Connect

    Nathaniel Steven Lee Phillips

    2006-12-12

    Superaustenitic stainless steels constitute a group of Fe-based alloys that are compositionally balanced to have a purely austenitic matrix and exhibit favorable pitting and crevice corrosion resistant properties and mechanical strength. However, intermetallic precipitates such as sigma and Laves can form during casting or exposure to high-temperature processing, which degrade the corrosion and mechanical properties of the material. The goal of this study was to accurately characterize the solid-solid phase transformations seen in cast superaustenitic stainless steels. Heat treatments were performed to understand the time and temperature ranges for intermetallic phase formations in alloys CN3MN and CK3MCuN. Microstructures were characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy and wavelength dispersive spectroscopy (EDS, WDS). The equilibrium microstructures, composed primarily of sigma and Laves within purely austenitic matrices, showed slow transformation kinetics. Factors that determine the extent of transformation, including diffusion, nucleation, and growth, are discussed.

  11. The USAMP magnesium powertrain cast components project

    NASA Astrophysics Data System (ADS)

    Powell, Bob R.

    2003-11-01

    The U.S. Automotive Materials Partnership (USAMP) and the U.S. Department of Energy launched the Magnesium Powertrain Cast Components Project in 2001 to determine the feasibility of producing a magnesiumintensive enginea six-cylinder engine with a magnesium block, bedplate, oil pan, and front cover. As the project approaches its midpoint, two goals are near completion: evaluation of the best available low-cost, creep-resistant magnesium alloys and design of engine components using the properties of the best alloys. Phase II of the project sets three additional goals: casting and testing the magnesium components in assembled powertrains, developing a powertrain magnesium alloy design database and common specification for magnesium powertrain alloys, and funding and promoting research to enable even more advanced powertrain applications in North America.

  12. Foam Filters Used in Gravity Casting

    NASA Astrophysics Data System (ADS)

    Hsu, Fu-Yuan; Lin, Huey-Jiuan

    2011-12-01

    Ceramic foam filters are normally used for reducing the velocity of liquid metal in the design of runner systems. In this study, four designs of the runner system with various orientations of foam filters were explored, and their effect on the velocity of the melt was estimated by a casting experiment and computational modeling. In the casting experiment, the free-fall trajectory and metal weighing methods were employed for measuring apparent velocity and flow rate, respectively. Using Forchheimer's equation, a porous material such as a foam filter was simulated. The modeling result was validated by the experiment. For the efficient use of a foam filter in a running system with a high flow rate but low exit velocity, an optimized design is recommended.

  13. Volatile Species Retention During Metallic Fuel Casting

    SciTech Connect

    Randall S. Fielding; Douglas L. Proter

    2013-10-01

    Metallic nuclear fuels are candidate transmutation fuel forms for advanced fuel cycles. Through the operation of the Experimental Breeder Reactor II metallic nuclear fuels have been shown to be robust and easily manufactured. However, concerns have been raised concerning loss of americium during the casting process because of its high vapor pressure. In order to address these concerns a gaseous diffusion model was developed and a series of experiments using both manganese and samarium as surrogates for americium were conducted. The modeling results showed that volatility losses can be controlled to essentially no losses with a modest overpressure. Experimental results also showed volatile species retention down to no detectable losses through overpressure, although the loss values varied from the model results the same trend was seen. Bases on these results it is very probably that americium losses through volatility can be controlled to no detectable losses through application of a modest overpressure during casting.

  14. Mold For Casting Radius-Inspection Specimens

    NASA Technical Reports Server (NTRS)

    Ball, Robert N.

    1988-01-01

    Thin replicas viewed on comparator without sectioning. New mold machined from piece of transparent poly(methyl methacrylate). Fits around base of post. Two slots machined into inner surface form channels for casting inspection sections. Bottom of mold fits flush against surface around bottom of post. When surface slanted, mold automatically aligns in proper orientation. Time required to inspect elliptical radii located at bottoms of series of small posts reduced from 18 hours to 3 hours.

  15. IMPROVED MAGNESIUM OXIDE SLIP CASTING METHOD

    DOEpatents

    Stoddard, S.D.; Nuckolls, D.E.

    1963-12-31

    A process for making an aqueous magnesium oxide slip casting slurry comprising the steps of mixing finely ground fused magnesium oxide with water, milling the slurry for at least 30 hours at a temperature of 2-10 deg C (the low temperature during milling inhibiting the formation of hydrated magnesium oxide), discharging the slurry from the mill, adding hydrochloric acid as a deflocculent, and adding a scum inhibitor is presented. (AEC)

  16. Thin Wall Cast Iron: Phase II

    SciTech Connect

    Doru M. Stefanescu

    2005-07-21

    The development of thin-wall technology allows the designers of energy consuming equipment to select the most appropriate material based on cost/material properties considerations, and not solely on density. The technology developed in this research project will permit the designers working for the automotive industry to make a better informed choice between competing materials and thin wall cast iron, thus decreasing the overall cost of the automobile.

  17. Efficient Runner Networks for Investment Castings

    SciTech Connect

    GIVLER,RICHARD C.; SAYLORS,DAVID B.

    2000-07-18

    We present a computational method that finds an efficient runner network for an investment casting, once the gate locations have been established. The method seeks to minimize a cost function that is based on total network volume. The runner segments are restricted to lie in the space not occupied by the part itself. The collection of algorithms has been coded in C and runner designs have been computed for several real parts, demonstrating substantial reductions in rigging volume.

  18. Fiber reinforcement of investment cast parts

    SciTech Connect

    Nolte, M.; Neussl, E.; Schaedlich-Stubenrauch, J.; Sahm, P.R.

    1993-12-31

    For 3 years now the Foundry-Institute (Giesserei-Institut) of the Aachen Institute of Technology has worked on the development of a new, low-cost production process for longfiber-reinforced light alloy components. The process baseline is oriented on the precision casting process in its investment casting mode, also known as lost wax process. The investment casting process is well known as a typical near-net-shape process for the manufacture of high-quality cast components, predominantly for applications in the aerospace industry (structured components, turbine blades and parts etc.) and enjoys significant growth rates during the last decades. After preliminary studies on the modification of single process substeps R & D work concentrated on the final-shape production of Al-components (Al-alloys A356, A357, 201 etc.) reinforced with long ceramic fibers. Both SiC and Al{sub 2}O{sub 3}-based fibers of several producers were used. Main interest focuses on techniques for a selective reinforcement of main stress sections. Without using conventional sintered preforms the fibers are infiltrated with molten metal under a support pressure of less than 1 MPa. Combined with a new developed wax pattern technique test specimens with a nearly homogeneous fiber distribution were produced. In addition, even reactive matrix alloys did not lead to destructive interface reactions. In most cases sufficient bonding between fibers and matrix could be observed. Following to these positive tendencies a considerable improvement of mechanical properties could be measured for longfiber reinforced Al-alloys. Both tensile strength and elastic modulus could be increased up to 100% compared with the unreinforced matrix alloy. Latest work concentrated on the production of small representative components for potential applications.

  19. INTERNAL ADAPTATION OF CAST TITANIUM CROWNS

    PubMed Central

    da Rocha, Sicknan Soares; Adabo, Gelson Luis; Ribeiro, Ricardo Faria; Fonseca, Renata Garcia

    2007-01-01

    As the adaptation of titanium crowns obtained by Rematitan Plus investment, specific for titanium, is not recognized to be suitable, this study evaluated the effect of the concentration of the specific liquid and the temperature of the mold of investments on the internal misfit of crowns cast on commercially pure titanium. Individual dies of epoxy resin were obtained, representing teeth prepared for full-crown restoration with a 6-degree axial surface convergence angle and shoulder (1.0 mm). For the waxing of each crown, a ring-shaped stainless steel matrix (8.0mm internal diameter; 7.5 mm height) was adapted above the individual dies of epoxy resin. The Rematian Plus investment was mixed according to the manufacturer's instructions using two different concentrations of the specific liquid: 100%, 75%. Casting was performed in a Discovery Plasma Ar-arc vacuum-pressure casting machine with molds at temperatures of 430C, 515C and 600C. The crowns were cleaned individually in a solution (1% HF + 13% HNO3) for 10 min using a ultrasonic cleaner, with no internal adaptations, and luted with zinc phosphate cement under a 5 kg static load. The crown and die assemblies were embedded in resin and sectioned longitudinally. The area occupied by cement was observed using stereoscopic lens (10X) and measured by the Leica Qwin image analysis system (mm2). The data for each experimental condition (n=8) were analyzed by Kruskal-Wallis non-parametric test (=0.05). The results showed that liquid dilution and the increase in mold temperature did not significantly influence the levels of internal fit of the cast titanium crowns. The lowest means (SD) of internal misfit were obtained for the 430C/100%: (7.25 mm2 1.59) and 600C/100% (8.8 mm2 2.25) groups, which presented statistically similar levels of internal misfit. PMID:19089139

  20. Refractory films from spin-cast polyacrylonitrile

    SciTech Connect

    Renschler, C.L.; Sylwester, A.P.

    1987-01-01

    Polyacrylonitrile (PAN) films have been spin-cast and pyrolyzed to produce thin (500 to 1500 A) carbon films. These films have higher electrical conductivities than carbon films produced by other methods at similar temperatures. The conductivity can be varied by at least four orders of magnitude by changing the pyrolysis temperature. UV, IR, and Raman spectroscopies were used to investigate the chemical structure of the films during different stages of processing.

  1. Innovative method for casting steel armorplate

    SciTech Connect

    Turner, P.C.; Hansen, J.S.

    1993-01-01

    The US Bureau of Mines, through an Interagency Agreement with the US Tank-Automotive Command (TACOM), has successfully developed a steel expendable pattern casting process (EPC) for the manufacture of armorplate. The new armor is lighter and more ballistically effective than conventional rolled homogeneous armor (RHA), and costs less. An applique armor spinoff from the program was field-tested during the Gulf War. The applique armor withstood direct impacts from enemy munitions without failure.

  2. Solidifying Cast Iron in Low Gravity

    NASA Technical Reports Server (NTRS)

    Hendrix, J. C.; Curreri, P. A.; Stefanescu, D. M.

    1986-01-01

    Report describes study of solidification of cast iron in low and normal gravity. Because flotation, sedimentation, and convection suppressed, alloys that solidify at nearly zero gravity have unusual and potentially useful characteristics. Study conducted in airplane that repeatedly flew along parabolic trajectories. Appears iron/carbon alloys made at low gravity have greater carbon content (as high as 5 to 10 percent) than those made of Earth gravity because carbon particles do not float to top of melt.

  3. Repair welding of gamma titanium aluminide castings

    NASA Astrophysics Data System (ADS)

    Kelly, T. J.

    This paper examines the GTA repair welding of cast Ti-48Al-2Cr-2Nb gamma titanium aluminide. Pre-weld heat treatment, preheat and welding parameters are evaluated and discussed. A wide range of GTAW parameters is demonstrated for use with this alloy and the resulting weld structure is examined. The effects of postweld heat treatment on the structure of the weld deposit is also determined.

  4. Influence of casting solvent on phenyl ordering at the surface of spin cast polymer thin films.

    PubMed

    Myers, John N; Zhang, Chi; Chen, Chunyan; Chen, Zhan

    2014-06-01

    Controlling the surface molecular structure of spin cast polymer films is important for the rational design of surface properties. However, the relationship between spin casting parameters and film surface molecular structure is poorly understood. We report that the surface molecular structure of spin cast homopolymers which contain phenyl groups is influenced by the solvent aromaticity, investigated by a nonlinear optical spectroscopy, sum frequency generation (SFG) vibrational spectroscopy. When phenyl groups were located in a linear polymer backbone, spin casting with aromatic solvents enhanced the phenyl SFG signal relative to when a non-aromatic solvent was used which suggests that the aromatic solvent induced the surface phenyl groups to be more ordered and/or to lie more perpendicular to the film surface. In addition, when alkyl structures were believed to be present at the solvent/air interface, alkyl structures were observed at the film/air interface which suggests that molecular structure at the solvent/air interface was carried to the film surface. The effects of solvent aromaticity on phenyl ordering at spin cast film surfaces can be explained by different molecular structures of polymer chains at solvent/air interfaces, preferential solvation of functional groups during evaporation, and re-orientation of bulky side groups at the polymer film/air interface. PMID:24703669

  5. The Simulation of Magnesium Wheel Low Pressure Die Casting Based on PAM-CAST

    NASA Astrophysics Data System (ADS)

    Peng, Yinghong; Wang, Yingchun; Li, Dayong; Zeng, Xiaoqin

    2004-06-01

    Magnesium is the lightest metal commonly used in engineering, with various excellent characteristics such as high strength and electromagnetic interference shielding capability. Particularly, the usage of magnesium in automotive industry can meet better the need to reduce fuel consumption and CO2 emissions. Nowadays, most current magnesium components in automobiles are made by die casting. In this paper, commercial software for die casting, PAM-CAST, was utilized to simulate the low pressure die casting process of magnesium wheel. Through calculating temperature field and velocity field during filling and solidification stages, the evolution of temperature distribution and liquid fraction was analyzed. Then, the potential defects including the gas entrapments in the middle of the spokes, shrinkages between the rim and the spokes were forecasted. The analytical results revealed that the mold geometry and die casting parameters should be improved in order to get the sound magnesium wheel. The reasons leading to these defects were also analyzed and the solutions to eliminate them were put forward. Furthermore, through reducing the pouring velocity, the air gas entrapments and partial shrinkages were eliminated effectively.

  6. Fisher Matrix Preloaded — FISHER4CAST

    NASA Astrophysics Data System (ADS)

    Bassett, Bruce A.; Fantaye, Yabebal; Hlozek, Renée; Kotze, Jacques

    The Fisher Matrix is the backbone of modern cosmological forecasting. We describe the Fisher4Cast software: A general-purpose, easy-to-use, Fisher Matrix framework. It is open source, rigorously designed and tested and includes a Graphical User Interface (GUI) with automated LATEX file creation capability and point-and-click Fisher ellipse generation. Fisher4Cast was designed for ease of extension and, although written in Matlab, is easily portable to open-source alternatives such as Octave and Scilab. Here we use Fisher4Cast to present new 3D and 4D visualizations of the forecasting landscape and to investigate the effects of growth and curvature on future cosmological surveys. Early releases have been available at since mid-2008. The current release of the code is Version 2.2 which is described here. For ease of reference a Quick Start guide and the code used to produce the figures in this paper are included, in the hope that it will be useful to the cosmology and wider scientific communities.

  7. Seal welded cast iron nuclear waste container

    DOEpatents

    Filippi, Arthur M.; Sprecace, Richard P.

    1987-01-01

    This invention identifies methods and articles designed to circumvent metallurgical problems associated with hermetically closing an all cast iron nuclear waste package by welding. It involves welding nickel-carbon alloy inserts which are bonded to the mating plug and main body components of the package. The welding inserts might be bonded in place during casting of the package components. When the waste package closure weld is made, the most severe thermal effects of the process are restricted to the nickel-carbon insert material which is far better able to accommodate them than is cast iron. Use of nickel-carbon weld inserts should eliminate any need for pre-weld and post-weld heat treatments which are a problem to apply to nuclear waste packages. Although the waste package closure weld approach described results in a dissimilar metal combination, the relative surface area of nickel-to-iron, their electrochemical relationship, and the presence of graphite in both materials will act to prevent any galvanic corrosion problem.

  8. Die Soldering in Aluminium Die Casting

    SciTech Connect

    Han, Q.; Kenik, E.A.; Viswanathan, S.

    2000-03-15

    Two types of tests, dipping tests and dip-coating tests were carried out on small steel cylinders using pure aluminum and 380 alloy to investigate the mechanism of die soldering during aluminum die casting. Optical and scanning electron microscopy were used to study the morphology and composition of the phases formed during soldering. A soldering mechanism is postulated based on experimental observations. A soldering critical temperature is postulated at which iron begins to react with aluminum to form an aluminum-rich liquid phase and solid intermetallic compounds. When the temperature at the die surface is higher than this critical temperature, the aluminum-rich phase is liquid and joins the die with the casting during the subsequent solidification. The paper discusses the mechanism of soldering for the case of pure aluminum and 380 alloy casting in a steel mold, the factors that promote soldering, and the strength of the bond formed when soldering occurs. conditions, an aluminum-rich soldering layer may also form over the intermetallic layer. Although a significant amount of research has been conducted on the nature of these intermetallics, little is known about the conditions under which soldering occurs.

  9. CAST: An Inspiring Axion Helioscope ala Sikivie

    SciTech Connect

    Zioutas, K.; Anastassopoulos, V.; Tsagri, M.; Semertzidis, Y.; Papaevangelou, T.

    2010-08-30

    CAST is a data taking axion helioscope using a recycled LHC test magnet, CERN's detector technology and cryogenics expertise. An imaging X-ray telescope improves substantially the detection sensitivity and axion-ID. Massive axion-like particles of the Kaluza-Klein type were first introduced to explain the paradox of the hot corona, which is even hotter at locations overlying magnetic spots. This is suggesting that the CAST detection principle might be at work there, but being somehow modified and performing better. Remarkably, the density profile of the Sun allows for resonance crossing (m{sub axion}c{sup 2{approx_equal}}h{omega}{sub plasma}), which axion helioscopes are aiming to reach. The restless Sun favours this occasionally even further. Then, such processes can give rise to a chimera of converted axions or the like, making the Sun appear, within known physics, as mysterious and unpredictable as it is. CAST axion limits were used to conclude also for the hidden sector paraphotons. This is then suggestive for novel helioscopes for exotica like paraphotons, chameleons, etc. Pierre Sikivie's pioneering idea was to use a magnetic field as a catalyst to transform particles from the dark sector to ours, and vice versa.

  10. Comparison of Lost Foam Casting of AM60B Alloy and A356 Alloy

    SciTech Connect

    Han, Qingyou; Dinwiddie, Ralph Barton; Sklad, Philip S; Currie, Kenneth; Vondra, Fred; Abdelrahman, Mohamed; Walford, Graham; Nolan, Dennis J; Nedkova, Teodora

    2007-01-01

    The article describes the research activities at Oak Ridge National Laboratory and Tennessee Technological University on lost foam casting of magnesium alloys. The work was focused on castings of simple geometries such as plate castings and window castings in order to compare the difference in castability between magnesium alloys and aluminum alloy using the lost foam casting process. Significant differences between lost foam aluminum casting and lost foam magnesium casting have been observed.

  11. Physical Simulation of Investment Casting of Complex Shape Parts

    NASA Astrophysics Data System (ADS)

    Rahimian, Mehdi; Milenkovic, Srdjan; Maestro, Laura; De Azua, Aitor Eguidazu Ruiz; Sabirov, Ilchat

    2015-05-01

    Development of investment casting process has been a challenge for manufacturers of complex shape parts. Numerous experimental casting trials are typically carried out to determine the optimum casting parameters for fabrication of high-quality products. In this work, it is demonstrated that physical simulation of investment casting can successfully predict microstructure and hardness in as-cast complex shape parts. The physical simulation tool consists of a thermal model and melting/solidification experiments in thermo-mechanical simulator. The thermal model is employed to predict local cooling rate during solidification at each point of a casting. Melting/solidification experiments are carried out under controlled cooling rates estimated by the thermal model. Microstructural and mechanical characterization of the solidified specimens is performed; the obtained results predict the local microstructure and mechanical properties of the casting. This concept is applied to investment casting of complex shape nozzle guide vanes from Mar-M247 Ni-based superalloy. Experimental casting trials are performed and the outcomes of physical simulation tool are validated against experimental results. It is shown that phase composition, secondary dendrite arm spacing, grain size, ?/ ?' eutectic size and volume fraction, size and shape of carbide particles, and local microhardness can be predicted at each point of the casting via physical simulation.

  12. X-ray computed tomography for casting development

    NASA Astrophysics Data System (ADS)

    Georgeson, Gary E.; Crews, Alan R.; Bossi, Richard H.

    1992-09-01

    Computed tomography (CT) has been used to evaluate specific sand casting product examples for technical and economic benefits. The representative results are applicable to other casting technologies as well. CT has been shown to be cost effective in the development of new castings. The areas which would benefit include internal dimensional measurements (eliminating destructive sectioning), specific region inspections, flaw characterization in critical regions (to allow passing or informed repair of castings), and geometric acquisition for CAD/CAM. The quantitative capability of CT allows an engineering evaluation of castings based upon a correlation with performance. This quantitative measurement capability has also been used to measure the benefit of hot isostatic pressing in casting production. CT is also cost effective for engineering design and analysis by providing rapid geometry acquisition for input to computer aided design systems. This is particularly beneficial for components that do not have existing drawings or cannot be adequately defined until they are made for any reason. Presently CT can serve as an engineering aid to casting manufacturing. In order for CT evaluation to become routine in foundry applications, however, casting designers need to call it out as a measurement technique in the original casting design drawings, specifications on the application of CT must be written, contracts must include CT evaluation as a means for accepting casting quality, and lower cost CT systems must be available.

  13. Centrifugal Casting Features/Metallurgical Characterization of Aluminum Alloys

    SciTech Connect

    Chirita, G.; Soares, D.; Cruz, D.; Silva, F. S.; Stefanescu, I.

    2008-02-15

    This paper deals with the study of centrifugal effects on aluminium castings under high G values. Most of the studies in this domain (FGMs obtained by centrifugal casting) deal with functionally graded composites reinforced with a solid phase such as silicon particles or others. However, in this study it will be shown that unreinforced aluminium alloys may be significantly influenced by the centrifugal effect and that functionally graded castings are also obtained. It has been observed that the centrifugal effect may increase in some alloys, depending on the relative position in the castings, the rupture strength by approx. 50%, and rupture strain by about 300%, as compared to the gravity casting technique. The Young's modulus may also increase by about 20%. It has also been reported that in vertical centrifugal castings there are mainly three aspects that affect the components thus obtained, namely: fluid dynamics; vibration (inherent to the system); and centrifugal force. These features have a different effect on the castings depending on the aluminium alloy. In this paper, an analysis of the most important effects of the centrifugal casting process on metallurgical features is conducted. A solidification characterization at several points along the mould will be made in order to have an accurate idea of both the fluid dynamics inside the mould during the casting and the solidification behavior in different parts of the component. These two analyses will be related to the metallurgical properties (phase distribution; SDAS; eutectic silicon content and shape, pores density and shape) along the component and mainly along the direction of the centrifugal pressure. A comparison between castings obtained by both centrifugal casting technique and gravity casting technique is made for reference (gravity casting)

  14. Abrasion Resistance of as-Cast High-Chromium Cast Iron

    NASA Astrophysics Data System (ADS)

    Pokusov, Marcela; Berta, Igor; oo, ?ubomr

    2014-12-01

    High chromium cast irons are widely used as abrasion resistant materials. Their properties and wear resistance depend on carbides and on the nature of the matrix supporting these carbides. The paper presents test results of irons which contain (in wt.%) 18-22 Cr and 2-5 C, and is alloyed by 1.7 Mo + 5 Ni + 2 Mn to improve the toughness. Tests showed as-cast irons with mostly austenitic matrix achieved hardness 36-53 HRC but their relative abrasion-resistance was higher than the tool steel STN 19436 heat treated on hardness 60 HRC.

  15. Method and mold for casting thin metal objects

    SciTech Connect

    Pehrson, Brandon P; Moore, Alan F

    2014-04-29

    Provided herein are various embodiments of systems for casting thin metal plates and sheets. Typical embodiments include layers of mold cavities that are oriented vertically for casting the metal plates. In some embodiments, the mold cavities include a beveled edge such that the plates that are cast have a beveled edge. In some embodiments, the mold cavities are filled with a molten metal through an open horizontal edge of the cavity. In some embodiments, the mold cavities are filled through one or more vertical feed orifices. Further disclosed are methods for forming a thin cast metal plate or sheet where the thickness of the cast part is in a range from 0.005 inches to 0.2 inches, and the surface area of the cast part is in a range from 16 square inches to 144 square inches.

  16. Tensile properties of as-cast iron-aluminide alloys

    SciTech Connect

    Viswanathan, S.; McKamey, C.G.; Maziasz, P.J.

    1995-01-01

    Room-temperature tensile properties of as-cast Fe{sub 3}Al-based FA-129 alloy were investigated. Tensile properties were obtained in the as-cast condition in air, oxygen, and water-vapor environments, and after homogenization at 700, 900, and 1200{degrees}C. Transmission electron microscopy (MM) was used to characterize ordered phases and dislocation structure, and optical metallography and scanning electron microscopy (SEM) were used to characterize the grain microstructure and fracture morphology. Tensile properties in the as-cast condition exhibited an environmental effect; tensile ductilities in oxygen atmosphere were greater than those obtained in laboratory air. Homogenized samples of FA-129 alloy exhibited almost twice the ductility found in the as-cast condition. Microstructural characterization of the homogenized samples and comparison of the as-cast and homogenized microstructures provided clues that helped to explain the poor ductility in the as-cast state.

  17. Acquired localised hypertrichosis in a Chinese child after cast immobilisation.

    PubMed

    Yuen, M W; Lai, Loretta K P; Chan, P F; Chao, David V K

    2015-08-01

    Hypertrichosis refers to excessive hair growth that is independent of any androgen effect. Hypertrichosis could be congenital or acquired, localised or generalised. The phenomenon of acquired localised hypertrichosis following cast application for a fracture is well known to orthopaedic surgeons, but is rarely encountered by primary care physicians. We describe a 28-month-old Chinese boy who had fracture of right leg as a result of an injury. He had a cast applied by an orthopaedic surgeon as treatment. On removal of the cast 6 weeks later, he was noticed to have significant hair growth on his right leg compared with the left leg. The patient was reassessed 3 months after removal of the cast. The hypertrichosis resolved completely with time. This patient was one of the youngest among the reported cases of acquired localised hypertrichosis after cast application. We illustrate the significance of management of post-cast-acquired localised hypertrichosis in the primary care setting. PMID:26238136

  18. Investment cast AISI H13 tooling for automotive applications

    SciTech Connect

    Maguire, M.C.; Baldwin, M.D.; Hochanadel, P.W.; Edwards, G.R.

    1995-07-01

    While many techniques exist for production of soft tooling, for die casting there is limited recent experience with cast tooling. The most common US alloy used for manufacture of die casting tooling is wrought AISI H13. If the performance of the cast material is comparable to the wrought counterpart, the use of investment cast HI 3 tooling directly from patterns made via rapid prototyping is of considerable interest. A metallurgical study of investment cast H13 was conducted to evaluate the mechanical behavior in simulated die casting applications. Variable thickness plate investment castings of AISI H13 hot work die steel were produced and characterized in the as-cast and heat-treated conditions. The characterization included light microscopy and mechanical testing. Wrought samples of standard and premium grade H13 were heat-treated and characterized similarly for comparison. Microstructural differences were observed in as-cast samples produced in different section thicknesses. Dendrite cell size and carbide morphology constituted the most prominent microstructural differences observed. After a full heat-treatment, microstructural differences between the wrought material and cast materials were slight regardless of section thickness.The mechanical properties of the cast and heat-treated material proved similar to the properties of the standard heat-treated wrought material. A thermal fatigue testing unit was to con-elate the heat checking susceptibility of H13 steel to its processing and consequent microstructural condition. Surface hardness decreased significantly with thermal cycling, and heat checking was observed in as few as 50 cycles. Thermal softening and thermal fatigue susceptibility were quantified and discussed relative to the microstructural conditions created by processing and heat-treatment. It was found that the premium grade wrought H13 steel provided the best overall resistance to heat checking.

  19. Radiographic evaluation of porosities in removable partial denture castings.

    PubMed

    Lewis, A J

    1978-03-01

    Most of the removable partial denture castings examined showed radiographic evidence of internal porosity. In general the porosity ocurred in characteristic regions associated with abrupt changes in cross-sectional thickness. These were located either within the partial denture framework or at the casting-sprue junctions. The porosity is due to metal shrinkage caused by a premature solidification at some point, which in turn interferes with a controlled unidirectional soldification of the casting. PMID:273090

  20. Cast prosthesis removal using ultrasonics and a thermoplastic resin adhesive.

    PubMed

    Parreira, F R; O'Connor, R P; Hutter, J W

    1994-03-01

    Nonsurgical endodontic procedures are routinely performed on teeth with existing cast restorations. The internal anatomy of the tooth and location of the root canals may be obscured by a crown or fixed partial denture. Tooth morphology and canal location may, therefore, be better visualized without the cast restoration in place. This article describes a conservative technique to remove an existing cast restoration to facilitate nonsurgical root canal treatment. PMID:7996088

  1. A simplified method of total contact casting for diabetic foot ulcers.

    PubMed

    Huband, M S; Carr, J B

    1993-02-01

    A simplified method of total contact casting for diabetic plantar ulcerations is described in which a standard, well-molded short-leg walking cast is applied. Weekly cast changes are performed initially, followed by longer cast change intervals. Either fiberglass or plaster casting tape appears equally efficacious. Healing of all ulcers was demonstrated in 12 patients treated with this technique. PMID:10148327

  2. Microporosity Prediction and Validation for Ni-based Superalloy Castings

    NASA Astrophysics Data System (ADS)

    Guo, J.; Beckermann, C.; Carlson, K.; Hirvo, D.; Bell, K.; Moreland, T.; Gu, J.; Clews, J.; Scott, S.; Couturier, G.; Backman, D.

    2015-06-01

    Microporosityin high performance aerospace castings can reduce mechanical properties and consequently degrade both component life and durability. Therefore, casting engineers must be able to both predict and reduce casting microporosity. A dimensionless Niyama model has been developed [1] that predicts local microporosity by accounting for local thermal conditions during casting as well as the properties and solidification characteristics of the cast alloy. Unlike the well-known Niyama criterion, application of the dimensionless Niyama model avoids the need to find a threshold Niyama criterion below which shrinkage porosity forms - a criterion which can be determined only via extensive alloy dependent experimentation. In the present study, the dimensionless Niyama model is integrated with a commercial finite element casting simulation software, which can now more accurately predict the location-specific shrinkage porosity volume fraction during solidification of superalloy castings. These microporosity predictions are validated by comparing modelled results against radiographically and metallographically measured porosity for several Ni-based superalloy equiaxed castings that vary in alloy chemistry with a focus on plates of changing draft angle and thickness. The simulation results agree well with experimental measurements. The simulation results also show that the dimensionless Niyama model can not only identify the location but also the average volume fraction of microporosity distribution in these equiaxed investment cast Ni-based superalloy experiments of relatively simple geometry.

  3. Advanced precision expendable pattern casting technology. 1994 Summary report

    SciTech Connect

    1995-05-01

    Casting technology is described. The following areas are reported on: precision pattern production; pattern coating; sand fill and compaction; pattern gating; mechanical properties; and technology transfer efforts.

  4. Numerical study of porosity in titanium dental castings.

    PubMed

    Wu, M; Sahm, P R; Augthun, M; Spiekermann, H; Schdlich-Stubenrauch, J

    1999-09-01

    A commercial software package, MAGMASOFT (MAGMA Giessereitechnologie GmbH, Aachen, Germany), was used to study shrinkage and gas porosity in titanium dental castings. A geometrical model for two simplified tooth crowns connected by a connector bar was created. Both mold filling and solidification of this casting model were numerically simulated. Shrinkage porosity was quantitatively predicted by means of a built-in feeding criterion. The risk of gas pore formation was investigated using the numerical filling and solidification results. The results of the numerical simulations were compared with experiments, which were carried out on a centrifugal casting machine with an investment block mold. The block mold was made of SiO2 based slurry with a 1 mm thick Zr2 face coat to reduce metal-mold reactions. Both melting and casting were carried out under protective argon (40 kPa). The finished castings were sectioned and the shrinkage porosity determined. The experimentally determined shrinkage porosity coincided with the predicted numerical simulation results. No apparent gas porosity was found in these model castings. Several running and gating systems for the above model casting were numerically simulated. An optimized running and gating system design was then experimentally cast, which resulted in porosity-free castings. PMID:15348102

  5. An heuristic based practical tool for casting process design

    SciTech Connect

    Nanda, N.K.; Smith, K.A.; Voller, V.R.; Haberle, K.F.

    1995-12-31

    The work in this paper reports on an heuristic based computer tool directed at casting process design; in particular key design parameters, such as part orientation, location of sprues, feeding rates, etc. The underlying principal used is that a given casting can be represented on identifying and classifying its critical features. The input to the system consists of the attributes of the features and the graphical output provides semi-quantitative information on key design parameters. Results on real castings match those of the expert casting designers and in some cases potential design improvements have been suggested by the system.

  6. Japanese R&D on new cast alloys and materials

    SciTech Connect

    Hayden, H.W.

    1996-05-01

    On the basis of observations of the JTEC team, it appears that Japanese universities and research institutes are leading long-term R&D thrusts for development of new materials casting technologies. Significant efforts include amorphous metals, intermetallics, application of MHD in continuous casting of steel, and energy efficient furnace technology. Industrial R&D seems focused more on process improvements than on new product technologies, but significant efforts in new cast materials included cast metal matrix composites, materials substitutions for thinner wall products, and advanced ceramic products for foundry industry applications.

  7. Tribological Properties of Al-SiC Metal Matrix Composites: A Comparison Between Sand Cast and Squeeze Cast Techniques

    NASA Astrophysics Data System (ADS)

    Ghosh, S.; Sahoo, P.; Sutradhar, G.

    2014-10-01

    Tribological behaviour of Al-SiC metal matrix composites prepared using two different fabrication techniques, viz. sand cast and squeeze cast techniques are studied in a multi- tribotester (TR-25, DUCOM, India) under dry sliding conditions and ambient atmosphere for varying volume fraction of reinforcement, applied load and sliding speed. Friction increases with increase in applied load and sliding speed and volume fraction of reinforcement. Wear test results show increased wear rates at higher load and speed, while increase in SiC volume fraction yields decrease in wear rate. Corrosion study conducted in 3.5 % NaCl solution shows that squeeze cast composites have better corrosion resistance than sand cast composites. Vickers's microhardness test shows improved hardness properties for squeeze cast composites compared to sand cast ones. The microstructure study of wear tracks reveals domination of abrasive wear with minor traces of adhesive wear.

  8. Aging degradation of cast stainless steel

    SciTech Connect

    Chopra, O.K.; Chung, H.M.

    1986-10-01

    A program is being conducted to investigate the significance of in-service embrittlement of cast duplex stainless steels under light-water reactor operating conditions. Microstructures of cast materials subjected to long-term aging either in reactor service or in the laboratory have been characterized by TEM, SANS, and APFIM techniques. Two precipitate phases, i.e., the Cr-rich ..cap alpha..' and Ni- and Si-rich G phase, have been identified in the ferrite matrix of the aged steels. The results indicate that the low-temperature embrittlement is primarily caused by ..cap alpha..' precipitates which form by spinodal decomposition. The relative contribution of G phase to loss of toughness is now known. Microstructural data also indicate that weakening of ferrite/austenite phase boundary by carbide precipitates has a significant effect on the onset and extent of embrittlement of the high-carbon CF-8 and CF-8M grades of stainless steels, particularly after aging at 400 or 450/sup 0/C. Data from Charpy-impact, tensile, and J-R curve tests for several heats of cast stainless steel aged up to 10,000 h at 350, 400, and 450/sup 0/C are presented and correlated with the microstructural results. Thermal aging of the steels results in an increase in tensile strength and a decrease in impact energy, J/sub IC/, and tearing modulus. The fracture toughness results show good agreement with the Charpy-impact data. The effects of compositional and metallurgical variables on loss of toughness are discussed.

  9. Modeling Coal Seam Damage in Cast Blasting

    SciTech Connect

    Chung, S.H.; Preece, D.S.

    1998-11-23

    A discrete element computer program named DMC_BLAST (Distinct Motion Code) has been under development since 1987 for modeling rock blasting (Preece & Taylor, 1989). This program employs explicit time integration and uses spherical or cylindrical elements that are represented as circles in two dimensions. DMC_BLAST calculations compare favorably with data from actual bench blasts (Preece et al, 1993). Coal seam chilling refers to the shattering of a significant portion of the coal leaving unusable fines. It is also refereed to as coal damage. Chilling is caused during a blast by a combination of explosive shock energy and movement of the adjacent rock. Chilling can be minimized by leaving a buffer zone between the bottom of the blastholes and the coal seam or by changing the blast design to decrease the powder factor or by a combination of both. Blast design in coal mine cast blasting is usually a compromise between coal damage and rock fragmentation and movement (heave). In this paper the damage to coal seams from rock movement is examined using the discrete element computer code DMC_BLAST. A rock material strength option has been incorporated into DMC_BLAST by placing bonds/links between the spherical particles used to model the rock. These bonds tie the particles together but can be broken when the tensile, compressive or shear stress in the bond exceeds the defined strength. This capability has been applied to predict coal seam damage, particularly at the toe of a cast blast where drag forces exerted by movement of the overlying rock can adversely effect the top of the coal at the bench face. A simulation of coal mine cast blasting has been performed with special attention being paid to the strength of the coal and its behavior at t he bench face during movement of the overlying material.

  10. Nonaqueous slip casting of high temperature ceramic superconductors using an investment casting technique

    NASA Astrophysics Data System (ADS)

    Hooker, Matthew W.; Taylor, Theodore D.; Wise, Stephanie A.; Buckley, John D.; Vasquez, Peter; Buck, Gregory M.; Hicks, Lana P.

    1993-08-01

    A process for slip casting ceramic articles that does not employ parting agents and affords the casting of complete, detailed, precision articles that do not possess parting lines is presented. This process is especially useful for high temperature superconductors and water-sensitive ceramics. A wax pattern for a shell mold is provided, and an aqueous mixture of a calcium sulfate-bonded investment material is applied as a coating to the wax pattern. The coated wax pattern is then dried, followed by curing to vaporize the wax pattern and leave a shell mold of the calcium sulfate-bonded investment material. The shell mold is cooled to room temperature, and a ceramic slip, created by dispersing a ceramic powder in an organic liquid, is poured therein. After a ceramic shell of desired thickness or a solid article has set up in the shell mold, excess ceramic slip is poured out. The shell mold is misted with water and peeled away from the ceramic article, after which the ceramic is fired to provide a complete, detailed, precision, high temperature superconductive ceramic article without parting lines. The casting technique may take place in the presence of a magnetic field to orient the ceramic powders during the casting process.

  11. Evaluation of the Inertness of Investment Casting Molds Using Both Sessile Drop and Centrifugal Casting Methods

    NASA Astrophysics Data System (ADS)

    Cheng, Xu; Yuan, Chen; Green, Nick; Withey, Paul

    2013-02-01

    The investment casting process is an economic production method for engineering components in TiAl-based alloys and offers the benefits of a near net-shaped component with a good surface finish. An investigation was undertaken to develop three new face coat systems based on yttria, but with better sintering properties. These face coat systems were mainly based on an yttria-alumina-zirconia system (Y2O3-0.5 wt pct Al2O3-0.5 wt pct ZrO2), an yttria-fluoride system (Y2O3-0.15 wt pct YF3), and an yttria-boride system (Y2O3-0.15 wt pct B2O3). After sintering, the chemical inertness of the face coat was first tested and analyzed using a sessile drop test through the metal wetting behavioral change for each face coat surface. Then, the interactions between the shell and metal were studied by centrifugal investment casting TiAl bars. Although the sintering aids in yttria can decrease the chemical inertness of the face coat, the thickness of the interaction layer in the casting was less than 10 ?m; therefore, these face coats still can be possible face coat materials for investment casting TiAl alloys.

  12. Method and apparatus for strip casting

    DOEpatents

    Follstaedt, Donald W.; Powell, John C.; Sussman, Richard C.; Williams, Robert S.

    1991-01-01

    Casting nozzles will provide improved flow conditions with the parameters controlled according to the present invention. The gap relationships between the nozzle slot and exit orifice must be controlled in combination with converging exit passageway to provide a smooth flow without shearing and turbulence in the stream. The nozzle lips are also rounded to improve flow and increase refractory life of the lips of the nozzle. The tundish walls are tapered to provide improve flow for supplying the melt to the nozzle. The nozzle is located about 45.degree. below top dead center for optimum conditions.

  13. Method and apparatus for strip casting

    DOEpatents

    Follstaedt, D.W.; Powell, J.C.; Sussman, R.C.; Williams, R.S.

    1991-11-12

    Casting nozzles will provide improved flow conditions with the parameters controlled according to the present invention. The gap relationships between the nozzle slot and exit orifice must be controlled in combination with converging exit passageway to provide a smooth flow without shearing and turbulence in the stream. The nozzle lips are also rounded to improve flow and increase refractory life of the lips of the nozzle. The tundish walls are tapered to provide improve flow for supplying the melt to the nozzle. The nozzle is located about 45[degree] below top dead center for optimum conditions. 2 figures.

  14. Electromagnetic continuous casting project: Final report

    SciTech Connect

    Battles, J.E.; Rote, D.M.; Misra, B.; Praeg, W.F.; Hull, J.R.; Turner, L.R.; Shah, V.L.; Lari, R.J.; Gopalsami, N.; Wiencek, T.

    1988-10-01

    This report describes the work on development of an electromagnetic casting process for steel, which was carried out at Argonne National Laboratory between January 1985 and December 1987. This effort was concerned principally with analysis and design work on magnet technology, liquid metal feed system, coolant system, and sensors and process controllers. Experimentation primarily involved (1) electromagnetic studies to determine the conditions and controlling parameters for stable levitation and (2) feed-system studies to establish important parameters that control and influence fluid flow from the liquid metal source to the caster. 73 refs., 91 figs., 11 tabs.

  15. Continuation of Crosscutting Technology Development at Cast

    SciTech Connect

    Yoon, Roe-Hoan

    2012-03-31

    This Final Technical Report describes progress made on the sub-projects awarded in the Cooperative Agreement DE-FC26-05NT42457: Continuation of Crosscutting Technology Development at Center for Advanced Separation Technologies (CAST). The final reports for each sub-project are attached in the appendix. Much of the research to be conducted with Cooperative Agreement funds will be longer-term, high-risk, basic research and will be carried out in five broad areas: a) Solid-solid separation b) Solid-liquid separation c) Chemical/Biological Extraction d) Modeling and Control, and e) Environmental Control.

  16. Phase transformations in cast duplex stainless steels

    NASA Astrophysics Data System (ADS)

    Kim, Yoon-Jun

    Duplex stainless steels (DSS) constitute both ferrite and austenite as a matrix. Such a microstructure confers a high corrosion resistance with favorable mechanical properties. However, intermetallic phases such as sigma (sigma) and chi (chi) can also form during casting or high-temperature processing and can degrade the properties of the DSS. This research was initiated to develop time-temperature-transformation (TTT) and continuous-cooling-transformation (CCT) diagrams of two types of cast duplex stainless steels, CD3MN (Fe-22Cr-5Ni-Mo-N) and CD3MWCuN (Fe-25Cr-7Ni-Mo-W-Cu-N), in order to understand the time and temperature ranges for intermetallic phase formation. The alloys were heat treated isothermally or under controlled cooling conditions and then characterized using conventional metallographic methods that included tint etching, and also using electron microscopy (SEM, TEM) and wavelength dispersive spectroscopy (WDS). The kinetics of intermetallic-phase (sigma + chi) formation were analyzed using the Johnson-Mehl-Avrami (JMA) equation in the case of isothermal transformations and a modified form of this equation in the case of continuous cooling transformations. The rate of intermetallic-phase formation was found to be much faster in CD3MWCuN than CD3MN due mainly to differences in the major alloying contents such as Cr, Ni and Mo. To examine in more detail the effects of these elements of the phase stabilities, a series of eight steel castings was designed with the Cr, Ni and Mo contents systematically varied with respect to the nominal composition of CD3MN. The effects of varying the contents of alloying additions on the formation of intermetallic phases were also studied computationally using the commercial thermodynamic software package, Thermo-Calc. In general, a was stabilized with increasing Cr addition and chi by increasing Mo addition. However, a delicate balance among Ni and other minor elements such as N and Si also exists. Phase equilibria in DSS can be affected by local composition fluctuations in the cast alloy. This may cause discrepancy between thermodynamic prediction and experimental observation.

  17. Phase Transformations in Cast Duplex Stainless Steels

    SciTech Connect

    Yoon-Jun Kim

    2004-12-19

    Duplex stainless steels (DSS) constitute both ferrite and austenite as a matrix. Such a microstructure confers a high corrosion resistance with favorable mechanical properties. However, intermetallic phases such as {sigma} and {chi} can also form during casting or high-temperature processing and can degrade the properties of the DSS. This research was initiated to develop time-temperature-transformation (TTT) and continuous-cooling-transformation (CCT) diagrams of two types of cast duplex stainless steels, CD3MN (Fe-22Cr-5Ni-Mo-N) and CD3MWCuN (Fe-25Cr-7Ni-Mo-W-Cu-N), in order to understand the time and temperature ranges for intermetallic phase formation. The alloys were heat treated isothermally or under controlled cooling conditions and then characterized using conventional metallographic methods that included tint etching, and also using electron microscopy (SEM, TEM) and wavelength dispersive spectroscopy (WDS). The kinetics of intermetallic-phase ({sigma} + {chi}) formation were analyzed using the Johnson-Mehl-Avrami (MA) equation in the case of isothermal transformations and a modified form of this equation in the case of continuous cooling transformations. The rate of intermetallic-phase formation was found to be much faster in CD3MWCuN than CD3MN due mainly to differences in the major alloying contents such as Cr, Ni and Mo. To examine in more detail the effects of these elements of the phase stabilities; a series of eight steel castings was designed with the Cr, Ni and Mo contents systematically varied with respect to the nominal composition of CD3MN. The effects of varying the contents of alloying additions on the formation of intermetallic phases were also studied computationally using the commercial thermodynamic software package, Thermo-Calc. In general, {sigma} was stabilized with increasing Cr addition and {chi} by increasing Mo addition. However, a delicate balance among Ni and other minor elements such as N and Si also exists. Phase equilibria in DSS can be affected by local composition fluctuations in the cast alloy. This may cause discrepancy between thermodynamic prediction and experimental observation.

  18. Sputtered protective coatings for die casting dies

    NASA Technical Reports Server (NTRS)

    Mirtich, M. J.; Nieh, C. Y.; Wallace, J. F.

    1981-01-01

    This investigation determined whether selected ion beam sputtered coatings on H-13 die steel would have the potential of improving the thermal fatigue behavior of the steel used as a die in aluminum die casting. The coatings were selected to test candidate insulators and metals capable of providing protection of the die surface. The studies indicate that 1 micrometer thick W and Pt coatings reduced the thermal fatigue more than any other coating tested and are candidates to be used on a die surface to increase die life.

  19. Cellularized Cellular Solids via Freeze-Casting.

    PubMed

    Christoph, Sarah; Kwiatoszynski, Julien; Coradin, Thibaud; Fernandes, Francisco M

    2016-02-01

    The elaboration of metabolically active cell-containing materials is a decisive step toward the successful application of cell based technologies. The present work unveils a new process allowing to simultaneously encapsulate living cells and shaping cell-containing materials into solid-state macroporous foams with precisely controlled morphology. Our strategy is based on freeze casting, an ice templating materials processing technique that has recently emerged for the structuration of colloids into macroporous materials. Our results indicate that it is possible to combine the precise structuration of the materials with cellular metabolic activity for the model organism Saccharomyces cerevisiae. PMID:26536388

  20. Refractory films from spin-cast carbon

    SciTech Connect

    Renschler, C.L.; Sylwester, A.P.

    1988-01-01

    A method is described to produce thin films of carbon by the pyrolysis of spin-cast polyacrylonitrile. Uv, ir, and Raman spectroscopies were employed to investigate the chemical structure of the films during pyrolysis. The electrical conductivity of films made in this way can be varied over several decades by changing the final temperature of carbonization. These films can also be photolithographically patterned and manipulated by wet and dry transfer techniques. As such, these films may have utility in microelectronic and hybrid microcircuit applications. 7 refs., 4 figs.

  1. [Ceramo-metallic bond of cast titanium].

    PubMed

    Bning, K; Walter, M

    1991-11-01

    The ceramo-metallic bond strength of cast titanium was tested according to DIN draft 13927. While the specimens failed in the bending tests, they clearly passed the 3-point bending test after removal of the surface reaction layer prior to firing. Light microscopy and SEM showed a satisfactory wetting of the titanium surface by the ceramic material. The result of X-ray analyses suggest that titanium particles are retained in the ceramic material when this layer is broken off its metallic substructure. PMID:1817878

  2. Reconciling the CAST and PVLAS results.

    PubMed

    Mohapatra, R N; Nasri, Salah

    2007-02-01

    The PVLAS experiment has recently claimed evidence for an axionlike particle in the milli-electron-volt mass range with a coupling to two photons that appears to be in contradiction with the negative results of the CAST experiment searching for solar axions. The simple axion interpretation of these two experimental results is therefore untenable and it has posed a challenge for theory. We propose a possible way to reconcile these two results by postulating the existence of an ultralight pseudoscalar particle interacting with two photons and a scalar boson and the existence of a low scale phase transition in the theory. PMID:17358829

  3. Casting dimensional control and fatigue life prediction for permanent mold casting dies. Technical report, September 29, 1993--May 31, 1997

    SciTech Connect

    1997-06-01

    Efforts as part of a three year program to address metal casting dimensional control and fatigue life prediction for permanent mold casting dies are described. Procedures have been developed and implemented to collect dimensional variability data from production steel casting. The influence of process variation and casting geometry variables on dimensional tolerances have been investigated. Also efforts leading to the developments and validation of a CAD/CAE model to predict the thermal fatigue life of permanent molds for aluminum castings are described. An appropriate thermomechanical property database for metal, mold and coating materials has been constructed. A finite element model has been developed to simulate the mold temperature distribution during repeated casting cycles. Validation trials using a permanent mold casting machine have indicated the success of the temperature distribution model developed. A combination of experimental and modeling techniques have been employed to extend their knowledge of permanent mold casting. The influence of coatings on casting solidification and mold temperatures has been determined. The computer model has been extended to predict thermally induced stresses and strains in the mold and to predict the number of cycles required to crack the mold. Experimental results have been used to validate the extended model.

  4. Spall behavior of cast iron with varying microstructures

    SciTech Connect

    Plume, Gifford; Rousseau, Carl-Ernst

    2014-07-21

    The spall strength of cast iron with varying microstructures has been investigated using plate impact at moderate speed. Stress history measurements were made with manganin stress gauges embedded between the back face of the specimen and a low impedance polycarbonate backing. Five separate cast irons were tested. Four of these consisted of gray cast iron with graphite in flake form, with three classified as Type VII A2 and the fourth containing a bimodal distribution of Types VII A4 and VII D8. The fifth casting consisted of ductile cast iron with graphite in nodular form, classified as Type I, size class 5. The spall strength for the Type VII A2 gray cast irons varied between 40 and 370 MPa, and that of the additional gray cast iron, between 410 and 490 MPa. The spall strength of the ductile cast iron fell within the range of 0.94–1.2 GPa. It is shown that the spall strength is linked to the damage level at the spall plane, where an increased level of tensile stress is required to generate higher levels of damage. Post mortem analysis was performed on the recovered samples, revealing the graphite phase to be the primary factor governing the spall fracture of cast irons, where crack nucleation is directly correlated to the debonding of graphite from the metal matrix. The average length of graphite found within a casting is linked to the material's strength, where strength increases as a function of decreasing length. The morphology and mean free path of graphite precipitates further govern the subsequent coalescence of initiated cracks to form a complete fracture plane. In cases where graphite spacing is large, increased energy level is required to complete the fracture process. A secondary factor governing the spall fracture of cast irons has also been linked to the microstructure of the metal matrix, with pearlite yielding higher spall strengths than free ferrite.

  5. Comparative study of two commercially pure titanium casting methods

    PubMed Central

    RODRIGUES, Renata Cristina Silveira; FARIA, Adriana Claudia Lapria; ORSI, Iara Augusta; de MATTOS, Maria da Gloria Chiarello; MACEDO, Ana Paula; RIBEIRO, Ricardo Faria

    2010-01-01

    The interest in using titanium to fabricate removable partial denture (RPD) frameworks has increased, but there are few studies evaluating the effects of casting methods on clasp behavior. Objective This study compared the occurrence of porosities and the retentive force of commercially pure titanium (CP Ti) and cobalt-chromium (Co-Cr) removable partial denture circumferential clasps cast by induction/centrifugation and plasma/vacuum-pressure. Material and Methods 72 frameworks were cast from CP Ti (n=36) and Co-Cr alloy (n=36; control group). For each material, 18 frameworks were casted by electromagnetic induction and injected by centrifugation, whereas the other 18 were casted by plasma and injected by vacuum-pressure. For each casting method, three subgroups (n=6) were formed: 0.25 mm, 0.50 mm, and 0.75 mm undercuts. The specimens were radiographed and subjected to an insertion/removal test simulating 5 years of framework use. Data were analyzed by ANOVA and Tukey's to compare materials and cast methods (α=0.05). Results Three of 18 specimens of the induction/centrifugation group and 9 of 18 specimens of plasma/vacuum-pressure cast presented porosities, but only 1 and 7 specimens, respectively, were rejected for simulation test. For Co-Cr alloy, no defects were found. Comparing the casting methods, statistically significant differences (p<0.05) were observed only for the Co-Cr alloy with 0.25 mm and 0.50 mm undercuts. Significant differences were found for the 0.25 mm and 0.75 mm undercuts dependent on the material used. For the 0.50 mm undercut, significant differences were found when the materials were induction casted. Conclusion Although both casting methods produced satisfactory CP Ti RPD frameworks, the occurrence of porosities was greater in the plasma/vacuum-pressure than in the induction/centrifugation method, the latter resulting in higher clasp rigidity, generating higher retention force values. PMID:21085805

  6. Spall behavior of cast iron with varying microstructures

    NASA Astrophysics Data System (ADS)

    Plume, Gifford; Rousseau, Carl-Ernst

    2014-07-01

    The spall strength of cast iron with varying microstructures has been investigated using plate impact at moderate speed. Stress history measurements were made with manganin stress gauges embedded between the back face of the specimen and a low impedance polycarbonate backing. Five separate cast irons were tested. Four of these consisted of gray cast iron with graphite in flake form, with three classified as Type VII A2 and the fourth containing a bimodal distribution of Types VII A4 and VII D8. The fifth casting consisted of ductile cast iron with graphite in nodular form, classified as Type I, size class 5. The spall strength for the Type VII A2 gray cast irons varied between 40 and 370 MPa, and that of the additional gray cast iron, between 410 and 490 MPa. The spall strength of the ductile cast iron fell within the range of 0.94-1.2 GPa. It is shown that the spall strength is linked to the damage level at the spall plane, where an increased level of tensile stress is required to generate higher levels of damage. Post mortem analysis was performed on the recovered samples, revealing the graphite phase to be the primary factor governing the spall fracture of cast irons, where crack nucleation is directly correlated to the debonding of graphite from the metal matrix. The average length of graphite found within a casting is linked to the material's strength, where strength increases as a function of decreasing length. The morphology and mean free path of graphite precipitates further govern the subsequent coalescence of initiated cracks to form a complete fracture plane. In cases where graphite spacing is large, increased energy level is required to complete the fracture process. A secondary factor governing the spall fracture of cast irons has also been linked to the microstructure of the metal matrix, with pearlite yielding higher spall strengths than free ferrite.

  7. Directional solidification of white cast iron

    NASA Astrophysics Data System (ADS)

    Park, J. S.; Verhoeven, J. D.

    1996-08-01

    Several studies of the ledeburite eutectic (Fe-Fe3C), in pure Fe-C alloys have shown that it has a lamellar morphology under plane front growth conditions. The structure of ledeburite in white cast irons, Fe-C-Si, consists of a rod morphology. It is generally not possible to produce plane front growth of Fe-C-Si eutectic alloys in the Fe-Fe3C form, because at the slow growth rates required for plane front growth, the Fe3C phase is replaced by graphite. By using small additions of Te, the growth of graphite was suppressed, and the plane front growth of the ledeburite eutectic in Fe-C-Si alloys was carried out with Si levels up to 1 wt pct. It was found that the growth morphology became a faceted rod morphology at 1 wt pct Si, but in contrast to the usual rod morphology of white cast irons, the rod phase was Fe3C rather than iron. It was shown that the usual rod morphology only forms at the sides of the two-phase cellular or dendritic growth fronts in Fe-C-Si alloys. Possible reasons for the inability of plane front directional solidification to produce the usual rod morphology in Fe-C-Si alloys are discussed. Also, data are presented on the spacing of the lamellar eutectic in pure Fe-C ledeburite, which indicates that this system does not follow the usual ?2 V = constant relation of regular eutectics.

  8. Shallow water model for horizontal centrifugal casting

    NASA Astrophysics Data System (ADS)

    Boh?ek, J.; Kharicha, A.; Ludwig, A.; Wu, M.

    2012-07-01

    A numerical model was proposed to simulate the solidification process of an outer shell of work roll made by the horizontal centrifugal casting technique. Shallow water model was adopted to solve the 2D average flow dynamics of melt spreading and the average temperature distribution inside the centrifugal casting mould by considering the centrifugal force, Coriolis force, viscous force due to zero velocity on the mould wall, gravity, and energy transport by the flow. Additionally, a 1D sub-model was implemented to consider the heat transfer in the radial direction from the solidifying shell to the mould. The solidification front was tracked by fulfilling the Stefan condition. Radiative and convective heat losses were included from both, the free liquid surface and the outer wall of the mould. Several cases were simulated with the following assumed initial conditions: constant height of the liquid metal (10, 20, and 30 mm), uniform temperature of the free liquid surface (1755 K). The simulation results have shown that while the solidification front remained rather flat, the free surface was disturbed by waves. The amplitude of waves increased with the liquid height. Free surface waves diminished as the solidification proceeded.

  9. Horizontal electromagnetic casting of thin metal sheets

    DOEpatents

    Hull, John R. (Hinsdale, IL); Lari, Robert J. (Aurora, IL); Praeg, Walter F. (Palos Park, IL); Turner, Larry R. (Naperville, IL)

    1987-01-01

    Thin metal sheets are cast by magnetically suspending molten metal deposited within a ferromagnetic yoke and between AC conducting coils and linearly displacing the magnetically levitated liquid metal while it is being cooled to form a solid metal sheet. Magnetic flux increases as the molten metal sheet moves downward and decreases as the molten metal sheet moves upward to stabilize the sheet and maintain it in equilibrium as it is linearly displaced and solidified by cooling gases. A conducting shield is electrically coupled to the molten metal sheet by means of either metal sheet engaging rollers or brushes on the solidified metal, and by means of an electrode in the vessel containing the molten metal thereby providing a return path for the eddy currents induced in the metal sheet by the AC coil generated magnetic flux. Variation in the geometry of the conducting shield allows the magnetic flux between the metal sheet and the conducting shield to be varied and the thickness in surface quality of the metal sheet to be controlled. Side guards provide lateral containment for the molten metal sheet and stabilize and shape the magnetic field while a leader sheet having electromagnetic characteristics similar to those of the metal sheet is used to start the casting process and precedes the molten metal sheet through the magnet and forms a continuous sheet therewith. The magnet may be either U-shaped with a single racetrack coil or may be rectangular with a pair of facing bedstead coils.

  10. Horizontal electromagnetic casting of thin metal sheets

    DOEpatents

    Hull, John R. (Hinsdale, IL); Lari, Robert J. (Aurora, IL); Praeg, Walter F. (Palos Park, IL); Turner, Larry R. (Naperville, IL)

    1988-01-01

    Thin metal sheets are cast by magnetically suspending molten metal deposited within a ferromagnetic yoke and between AC conducting coils and linearly displacing the magnetically levitated liquid metal while it is being cooled to form a solid metal sheet. Magnetic flux increases as the molten metal sheet moves downward and decreases as the molten metal sheet moves upward to stabilize the sheet and maintain it in equilibrium as it is linearly displaced and solidified by cooling gases. A conducting shield is electrically coupled to the molten metal sheet by means of either metal sheet engaging rollers or brushes on the solidified metal, and by means of an electrode in the vessel containing the molten metal thereby providing a return path for the eddy currents induced in the metal sheet by the AC coil generated magnetic flux. Variation in the geometry of the conducting shield allows the magnetic flux between the metal sheet and the conducting shield to be varied and the thickness in surface quality of the metal sheet to be controlled. Side guards provide lateral containment for the molten metal sheet and stabilize and shape the magnetic field while a leader sheet having electromagnetic characteristics similar to those of the metal sheet is used to start the casting process and precedes the molten metal sheet through the magnet and forms a continuous sheet therewith. The magnet may be either U-shaped with a single racetrack coil or may be rectangular with a pair of facing bedstead coils.

  11. Advanced Lost Foam Casting Technology - Phase V

    SciTech Connect

    Wanliang Sun; Harry E. Littleton; Charles E. Bates

    2004-04-29

    Previous research, conducted under DOE Contracts DE-FC07-89ID12869, DE-FC07-93ID12230 and DE-FC07-95ID113358 made significant advances in understanding the Lost Foam Casting (LFC) Process and clearly identified areas where additional developments were needed to improve the process and make it more functional in industrial environments. The current project focused on eight tasks listed as follows: Task 1--Computational Model for the Process and Data Base to Support the Model; Task 2--Casting Dimensional Accuracy; Task 3--Pattern Production; Task 4--Improved Pattern Materials; Task 5--Coating Control; Task 6--In-Plant Case Studies; Task 7--Energy and the Environmental Data; and Task 8--Technology Transfer. This report summarizes the work done on all tasks in the period of October 1, 1999 through September 30, 2004. The results obtained in each task and subtask are summarized in this Executive Summary and details are provided in subsequent sections of the report.

  12. Software Computes Tape-Casting Parameters

    NASA Technical Reports Server (NTRS)

    deGroh, Henry C., III

    2003-01-01

    Tcast2 is a FORTRAN computer program that accelerates the setup of a process in which a slurry containing metal particles and a polymeric binder is cast, to a thickness regulated by a doctor blade, onto fibers wound on a rotating drum to make a green precursor of a metal-matrix/fiber composite tape. Before Tcast2, setup parameters were determined by trial and error in time-consuming multiple iterations of the process. In Tcast2, the fiber architecture in the final composite is expressed in terms of the lateral distance between fibers and the thickness-wise distance between fibers in adjacent plies. The lateral distance is controlled via the manner of winding. The interply spacing is controlled via the characteristics of the slurry and the doctor-blade height. When a new combination of fibers and slurry is first cast and dried to a green tape, the shrinkage from the wet to the green condition and a few other key parameters of the green tape are measured. These parameters are provided as input to Tcast2, which uses them to compute the doctor-blade height and fiber spacings needed to obtain the desired fiber architecture and fiber volume fraction in the final composite.

  13. Aluminum Alloy and Article Cast Therefrom

    NASA Technical Reports Server (NTRS)

    Lee, Jonathan A. (Inventor); Chen, Po-Shou (Inventor)

    2003-01-01

    A cast article from an aluminum alloy, which has improved mechanical properties at elevated temperatures, has the following composition in weight percent: Silicon 14 - 25.0, Copper 5.5 - 8.0, Iron 0.05 - 1.2, Magnesium 0.5 - 1.5, Nickel 0.05 - 0.9, Manganese 0.05 - 1.0, Titanium 0.05 - 1.2, Zirconium 0.05 - 1.2, Vanadium 0.05 - 1.2, Zinc 0.05 - 0.9, Phosphorus 0.001 - 0.1, and the balance is Aluminum, wherein the silicon-to-magnesium ratio is 10 - 25, and the copper-to-magnesium ratio is 4 - 15. The aluminum alloy contains a simultaneous dispersion of three types of Al3X compound particles (X=Ti, V, Zr) having a LI2, crystal structure, and their lattice parameters are coherent to the aluminum matrix lattice. A process for producing this cast article is also disclosed, as well as a metal matrix composite, which includes the aluminum alloy serving as a matrix and containing up to about 60% by volume of a secondary filler material.

  14. Energy Saving Melting andRevert Reduction Technology (E0SMARRT): Predicting Pattern Tooling and Casting Dimension for Investment Casting

    SciTech Connect

    Nick Cannell; Dr. Mark Samonds; Adi Sholapurwalla; Sam Scott

    2008-11-21

    The investment casting process is an expendable mold process where wax patterns of the part and rigging are molded, assembled, shelled and melted to produce a ceramic mold matching the shape of the component to be cast. Investment casting is an important manufacturing method for critical parts because of the ability to maintain dimensional shape and tolerances. However, these tolerances can be easily exceeded if the molding components do not maintain their individual shapes well. In the investment casting process there are several opportunities for the final casting shape to not maintain the intended size and shape, such as shrinkage of the wax in the injection tool, the modification of the shape during shell heating, and with the thermal shrink and distortion in the casting process. Studies have been completed to look at the casting and shell distortions through the process in earlier phases of this project. Dr. Adrian Sabau at Oak Ridge National Labs performed characterizations and validations of 17-4 PH stainless steel in primarily fused silica shell systems with good agreement between analysis results and experimental data. Further tasks provided material property measurements of wax and methodology for employing a viscoelastic definition of wax materials into software. The final set of tasks involved the implementation of the findings into the commercial casting analysis software ProCAST, owned and maintained by ESI Group. This included: o the transfer of the wax material property data from its raw form into separate temperature-dependent thermophysical and mechanical property datasets o adding this wax material property data into an easily viewable and modifiable user interface within the pre-processing application of the ProCAST suite, namely PreCAST o and validating the data and viscoelastic wax model with respect to experimental results

  15. AUTOMATED MALLEABLE ANNEALING OVENS SLOWLY HEAT AND COOL CASTINGS AS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    AUTOMATED MALLEABLE ANNEALING OVENS SLOWLY HEAT AND COOL CASTINGS AS THEY MOVE IN BINS ALONG TRACKS IN THE OVEN BOTTOM IN THE MALLEABLE ANNEALING BUILDING. THIS PROCESS TRANSFORMS BRITTLE WHITE IRON CASTINGS INTO SOFTER, STRONGER MALLEABLE IRON. - Stockham Pipe & Fittings Company, Malleable Annealing Building, 4000 Tenth Avenue North, Birmingham, Jefferson County, AL

  16. Filtration efficiency in casting of a complexly alloyed nickel melt

    NASA Astrophysics Data System (ADS)

    Sidorov, V. V.; Iskhodzhanova, I. V.; Rigin, V. E.; Folomeikin, Yu. I.

    2012-12-01

    The use of a cellular ceramic filter is shown to be effective for casting nickel superalloys in vacuum, including superalloys cast using wastes. As a result of filtration, the volume fraction of nonmetallic inclusions and their sizes and quantity in a metal decrease.

  17. GUIDES TO POLLUTION PREVENTION: METAL CASTING AND HEAT TREATING INDUSTRY

    EPA Science Inventory

    This guide provides an overview of the major waste generating process of metal casting and heat treating operations and presents options for reducing this waste through source reduction and recycling. ost waste generated by the metal casting, or foundry, industry is from melting ...

  18. 49 CFR 192.755 - Protecting cast-iron pipelines.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Protecting cast-iron pipelines. 192.755 Section... NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Maintenance 192.755 Protecting cast-iron pipelines. When an operator has knowledge that the support for a segment of a buried...

  19. 49 CFR 192.755 - Protecting cast-iron pipelines.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Protecting cast-iron pipelines. 192.755 Section... NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Maintenance 192.755 Protecting cast-iron pipelines. When an operator has knowledge that the support for a segment of a buried...

  20. 49 CFR 192.755 - Protecting cast-iron pipelines.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Protecting cast-iron pipelines. 192.755 Section... NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Maintenance 192.755 Protecting cast-iron pipelines. When an operator has knowledge that the support for a segment of a buried...

  1. Refining cast implant-retained restorations by electrical discharge machining.

    PubMed

    Schmitt, S M; Chance, D A; Cronin, R J

    1995-03-01

    The UCLA abutment was developed to create implant-retained restorations with ideal contours, excellent esthetics, and minimal vertical space requirements for restorative materials. A major drawback of this abutment is that casting inaccuracies in the lost-wax process are difficult to control. This article describes a method of refining cast implant-retained restorations by use of electrical discharge machining. PMID:7760278

  2. Two from One Casting. Art Education: 6681.20.

    ERIC Educational Resources Information Center

    Hilf, Anne

    Two From One Casting is a studio course dealing with exploratory applications of casting methods and materials for students in grades 7 through 12 who wish to make permanent those creations easily destroyed by time or negligence. Course rationale, enrollment guidelines, objectives, outline of content, descriptions of activities and procedures,

  3. LUNG MODEL CASTING TECHNIQUES FOR INTERSPECIES MORPHOMETRIC COMPARISONS

    EPA Science Inventory

    Techniques have been developed for casting both solid and hollow lung models from lung specimens. These techniques have been used to make casts of rat, rabbit, baboon, and human lungs and may be used for other species. An air line at a positive pressure of 25 cm of water is conne...

  4. QUENCHING TUMBLING MILL TUMBLES CASTINGS OVER EACH OTHER TO REMOVE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    QUENCHING TUMBLING MILL TUMBLES CASTINGS OVER EACH OTHER TO REMOVE RUNNERS AND SPRUES WHILE QUICKLY COOLING THEM WITH WATER IN THE MALLEABLE ANNEALING BUILDING. THIS PROCESS ENSURES CASTINGS FORM WHITE IRON PRIOR TO BEING ASSEMBLED. - Stockham Pipe & Fittings Company, Malleable Annealing Building, 4000 Tenth Avenue North, Birmingham, Jefferson County, AL

  5. 126. EXTERIOR VIEW, LOOKING NORTH, SHOWING CAST SHED NO. 2, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    126. EXTERIOR VIEW, LOOKING NORTH, SHOWING CAST SHED NO. 2, FURNACE NO. 2, STOVES, POWER HOUSE, STACKS, FURNACE NO. 1 CAST SHED. FURNACE NO. 2 IS IN PROCESS OF RESTORATION. - Sloss-Sheffield Steel & Iron, First Avenue North Viaduct at Thirty-second Street, Birmingham, Jefferson County, AL

  6. The twin-roll strip casting of magnesium

    NASA Astrophysics Data System (ADS)

    Liang, D.; Cowley, C. B.

    2004-05-01

    Commonwealth Scientific & Industrial Research Organization has been working since 2000 to develop twin-roll strip casting of magnesium alloy. The primary objective was to significantly reduce the manufacturing cost of the magnesium sheet through the twin-roll casting process. This article describes the goals and challenges of this project as well as pilot plant test results.

  7. Rapid Tooling via Investment Casting and Rapid Prototype Patterns

    SciTech Connect

    Baldwin, Michael D.

    1999-06-01

    The objective of this work to develop the materials processing and design technologies required to reduce the die development time for metal mold processes from 12 months to 3 months, using die casting of Al and Mg as the example process. Sandia demonstrated that investment casting, using rapid prototype patterns produced from Stereo lithography or Selective laser Sintering, was a viable alternative/supplement to the current technology of machining form wrought stock. A demonstration die insert (ejector halt) was investment cast and subsequently tested in the die casting environment. The stationary half of the die insert was machined from wrought material to benchmark the cast half. The two inserts were run in a die casting machine for 3,100 shots of aluminum and at the end of the run no visible difference could be detected between the cast and machined inserts. Inspection concluded that the cast insert performed identically to the machined insert. Both inserts had no indications of heat checking or degradation.

  8. Fiberglass versus plaster casts. How to choose between them.

    PubMed

    Silfverskiold, J P

    1989-10-01

    Both fiberglass and plaster of Paris casts have advantages and disadvantages, and the choice of material depends on the individual situation. Fiberglass is used most often, but plaster of Paris, with its molding capabilities, is the first choice for fresh extremity fractures. "Hybrid" casts offer no advantages. PMID:2636865

  9. 91. VIEW NORTHWEST OF SCRAP HOUSE AND CAST HOUSE, BUILDINGS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    91. VIEW NORTHWEST OF SCRAP HOUSE AND CAST HOUSE, BUILDINGS 101 AND 72; BUILDING 101 IN THE CENTER OF THE PHOTOGRAPH HOUSED SCRAP METAL CLEANING AND PROCESSING FACILITIES; BUILDING 72 AT RIGHT CENTER HOUSED MELTING FURNACES AND CONTINUOUS CASTING MACHINERY - Scovill Brass Works, 59 Mill Street, Waterbury, New Haven County, CT

  10. The Childhood Autism Spectrum Test (CAST): Sex Differences

    ERIC Educational Resources Information Center

    Williams, Joanna G.; Allison, Carrie; Scott, Fiona J.; Bolton, Patrick F.; Baron-Cohen, Simon; Matthews, Fiona E.; Brayne, Carol

    2008-01-01

    The Childhood Autism Spectrum Test (CAST) (formally known as the Childhood Asperger Screening Test) identifies autism spectrum conditions by measuring social and communication skills. The present study explored the sex distribution of scores. The CAST was distributed to 11,635 children aged 4-9 years in Cambridgeshire primary schools (UK). 3,370

  11. Properties of a hybrid plaster-fibreglass cast

    PubMed Central

    Charles, Mark N.; Yen, David

    2000-01-01

    Objective To examine the suitability of a plaster-fibreglass hybrid cast for orthopedic applications, comparing them to plaster of Paris (POP) and fibreglass constructs. Method Groups of 10 standardized hybrid, POP and fibreglass casts were studied. An Instron servo-hydraulic system was used to test the casts in 3-point bending and shear. Outcome measures Strength, stiffness, weight, thickness and cost of the 3 types of cast, and shear strength at the interface between the POP and fibreglass in the hybrid casts. Results The hybrid casts were twice as strong as the POP constructs, were stiffer and weighed 14% less but were thicker and cost 2.5 times more. They were almost as strong as and less than half the cost of the fibreglass constructs but were thicker, not as stiff, and weighed 42% more. The shear strength of the POPfibreglass interface in the hybrid casts was higher than the 3-point bending strength of this construct by a factor of 3. Conclusions Plaster-fibreglass hybrid casts should be considered for orthopedic use on the basis of their strength, stiffness, weight and cost, combined with their acknowledged advantages of good moulding ability and water resistance. PMID:11045095

  12. High-resolution airway morphometry from polyurethane casts

    NASA Astrophysics Data System (ADS)

    Neufeld, Gordon R.; Vargas, John; Hoford, John D.; Craft, Jeanne; Shroff, Sunil; McRae, Karen M.

    1995-05-01

    An airway cast was made and imbedded in a solid polyurethane block of a contrasting color. The block was sequentially milled and photographed. The sequential photographs were scanned to create an image database which was analyzed on VIDA; a multidimensional image analysis software package. The technique shows promise as a semi-automated process for generating a high resolution morphometric database from airway casts.

  13. Start with Casting: What to Know before Auditions Begin.

    ERIC Educational Resources Information Center

    Carlisle, Barbara; Drapeau, Don

    1997-01-01

    Outlines steps in casting a play: the group should choose a piece with the group in mind; people should be shown off to their best advantage; and ageism, sexism, or racism should not enter the casting process. Performance reality should be kept in mind. (PA)

  14. INTERIOR VIEW WITH LARGE PIPE CASTING MACHINE AND BRIDGE CRANE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR VIEW WITH LARGE PIPE CASTING MACHINE AND BRIDGE CRANE PICKING UP A 48' PIPE FOR WEIGHING AND TRANSFER TO ANNEALING OVEN. - United States Pipe & Foundry Company Plant, Pipe Casting & Testing Area, 2023 St. Louis Avenue at I-20/59, Bessemer, Jefferson County, AL

  15. 8. VIEW OF A MOLD FOR PRECISION CASTING. THE MOLD ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. VIEW OF A MOLD FOR PRECISION CASTING. THE MOLD WAS USED IN FOUNDRY OPERATIONS THAT CAST PLUTONIUM EITHER AS INGOTS SUITABLE FOR ROLLING AND FURTHER WROUGHT PROCESSING OR INTO SHAPES AMENABLE TO DIRECT MACHINING OPERATIONS. (5/6/59) - Rocky Flats Plant, Plutonium Fabrication, Central section of Plant, Golden, Jefferson County, CO

  16. A Note on the Comparative View of Caste

    ERIC Educational Resources Information Center

    Schermerhorn, R. A.

    1972-01-01

    An important division of opinion on the nature of caste has developed among a number of prominent authorities on the sociology and anthropology of India. In this regard, the ideas of M. V. Shrinivas, T. B. Bottomore, E. R. Leach and Gerald Berreman are discussed. Comparison is made between caste in India and racial stratification in the United

  17. Casting Porosity-Free Grain Refined Magnesium Alloys

    SciTech Connect

    Schwam, David

    2013-08-12

    The objective of this project was to identify the root causes for micro-porosity in magnesium alloy castings and recommend remedies that can be implemented in production. The findings confirm the key role played by utilizing optimal gating and risering practices in minimizing porosity in magnesium castings. 

  18. RAW COPPER SLABS USED IN CASTING OPERATIONS AT BUFFALO PLANT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    RAW COPPER SLABS USED IN CASTING OPERATIONS AT BUFFALO PLANT OF AMERICAN BRASS COMPANY. MATERIALS STORAGE FOR THE CAST SHOP NOW OCCUPIES A PORTION OF THE ORIGINAL BRASS MILL BUILT BY THE BUFFALO COPPER AND BRASS ROLLING MILL IN 1906-07 AND EXPANDED IN 1911. - American Brass Foundry, 70 Sayre Street, Buffalo, Erie County, NY

  19. 49 CFR 192.755 - Protecting cast-iron pipelines.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Protecting cast-iron pipelines. 192.755 Section... NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Maintenance 192.755 Protecting cast-iron pipelines. When an operator has knowledge that the support for a segment of a buried...

  20. Method and apparatus for planar drag strip casting

    DOEpatents

    Powell, J.C.; Campbell, S.L.

    1991-11-12

    The present invention is directed to an improved process and apparatus for strip casting. The combination of a planar flow casting nozzle positioned back from the top dead center position with an attached nozzle extension, provides an increased level of casting control and quality. The nozzle extension provides a means of containing the molten pool above the rotating substrate to increase the control of molten metal at the edges of the strip and increase the range of coating thicknesses which may be produced. The level of molten metal in the containment means is regulated to be above the level of melt supplying the casting nozzle which produces a condition of planar drag flow with the casting substrate prior to solidification. 5 figures.

  1. Method and apparatus for planar drag strip casting

    DOEpatents

    Powell, John C.; Campbell, Steven L.

    1991-01-01

    The present invention is directed to an improved process and apparatus for strip casting. The combination of a planar flow casting nozzle positioned back from the top dead center position with an attached nozzle extension, provides an increased level of casting control and quality. The nozzle extension provides a means of containing the molten pool above the rotating substrate to increase the control of molten metal at the edges of the strip and increase the range of coating thicknesses which may be produced. The level of molten metal in the containment means is regulated to be above the level of melt supplying the casting nozzle which produces a condition of planar drag flow with the casting substrate prior to solidification.

  2. Tensile-property characterization of thermally aged cast stainless steels.

    SciTech Connect

    Michaud, W. F.; Toben, P. T.; Soppet, W. K.; Chopra, O. K.; Energy Technology

    1994-03-03

    The effect of thermal aging on tensile properties of cast stainless steels during service in light water reactors has been evaluated. Tensile data for several experimental and commercial heats of cast stainless steels are presented. Thermal aging increases the tensile strength of these steels. The high-C Mo-bearing CF-8M steels are more susceptible to thermal aging than the Mo-free CF-3 or CF-8 steels. A procedure and correlations are presented for predicting the change in tensile flow and yield stresses and engineering stress-vs.-strain curve of cast stainless steel as a function of time and temperature of service. The tensile properties of aged cast stainless steel are estimated from known material information, i.e., chemical composition and the initial tensile strength of the steel. The correlations described in this report may be used for assessing thermal embrittlement of cast stainless steel components.

  3. Complex foamed aluminum parts as permanent cores in aluminum castings

    SciTech Connect

    Simancik, F.; Schoerghuber, F.

    1998-12-31

    The feasibility of complex shaped aluminum foam parts as permanent cores in aluminum castings has been investigated. The foamed samples were prepared by injection of the foam into sand molds. It turned out that sound castings can be produced if the foam core is properly preheated and/or surface treated before casting. The effect of the foam core on the performance of the casting was evaluated by in compression testing and by measuring structural damping. The gain in the related properties turned out to be much higher than the weight increase of the casting due to the presence of the core. The weight increase may be partially offset through a reduction of the wall-thickness of the shell.

  4. Tensile-property characterization of thermally aged cast stainless steels

    SciTech Connect

    Michaud, W.F.; Toben, P.T.; Soppet, W.K.; Chopra, O.K.

    1994-02-01

    The effect of thermal aging on tensile properties of cast stainless steels during service in light water reactors has been evaluated. Tensile data for several experimental and commercial heats of cast stainless steels are presented. Thermal aging increases the tensile strength of these steels. The high-C Mo-bearing CF-8M steels are more susceptible to thermal aging than the Mo-free CF-3 or CF-8 steels. A procedure and correlations are presented for predicting the change in tensile flow and yield stresses and engineering stress-vs.-strain curve of cast stainless steel as a function of time and temperature of service. The tensile properties of aged cast stainless steel are estimated from known material information, i.e., chemical composition and the initial tensile strength of the steel. The correlations described in this report may be used for assessing thermal embrittlement of cast stainless steel components.

  5. Waterproof versus cotton cast liners: a randomized, prospective comparison.

    PubMed

    Haley, Chad A; DeJong, E Schuyler; Ward, John A; Kragh, John F

    2006-03-01

    Casting injured extremities can cause complications (eg, itching, odor, rashes, skin maceration), many of which are associated with the inability to wash the extremity because of water retention and slow drying of conventional cast liners. A waterproof cast liner allows casts to become wet and perhaps improves hygiene and comfort. Fifty-nine patients (age, > or = 10 years) with upper or lower extremity injuries were randomized to a waterproof-liner group (n = 29) or a cotton-liner group (n = 30). Both groups had casts made of fiberglass tape. At each clinic visit, patients and physicians completed questionnaires evaluating comfort and skin condition, respectively. The waterproof-liner group had better scores for itch (P = .008), discomfort (P < .001), irritation (P = .002), overall patient score (P = .012), and overall physician score (P = .049). PMID:16610379

  6. Cast-iron main break predictive models guide maintenance plans

    SciTech Connect

    Lochbaum, B.S. )

    1994-04-01

    Public Service Electric and Gas Co. (PSE and G), with more cast iron than any other utility in the US, has developed cast-iron main break predictive models encompassing effects of weather, soils, corrosivity, installation vintage and annual replacement footage. While these models will not produce a segment-by-segment replacement priority listing, they will highlight geographic areas of cast iron vintages that are more at risk than others. The models are comprised primarily of information readily accessible to most gas utilities. PSE and G's distribution network consists of more than 15,000 mi of main of which 5,100 mi, or 34%, is cast iron. Developing informational tools about cast-iron main reliability has been pursued by the company in various studies, and some of the results have been incorporated into the system management philosophy.

  7. Grain Refinement of Permanent Mold Cast Copper Base Alloys

    SciTech Connect

    M.Sadayappan; J.P.Thomson; M.Elboujdaini; G.Ping Gu; M. Sahoo

    2005-04-01

    Grain refinement is a well established process for many cast and wrought alloys. The mechanical properties of various alloys could be enhanced by reducing the grain size. Refinement is also known to improve casting characteristics such as fluidity and hot tearing. Grain refinement of copper-base alloys is not widely used, especially in sand casting process. However, in permanent mold casting of copper alloys it is now common to use grain refinement to counteract the problem of severe hot tearing which also improves the pressure tightness of plumbing components. The mechanism of grain refinement in copper-base alloys is not well understood. The issues to be studied include the effect of minor alloy additions on the microstructure, their interaction with the grain refiner, effect of cooling rate, and loss of grain refinement (fading). In this investigation, efforts were made to explore and understand grain refinement of copper alloys, especially in permanent mold casting conditions.

  8. Durability of Quick Reaction Satellite Antenna (QRSA) trunnion castings

    NASA Astrophysics Data System (ADS)

    Wang, Wego; Wells, Martin G.

    1993-03-01

    Repeated failures of quick reaction satellite antenna (QRSA) trunnion castings in the field caused alarming concerns about their durability. Arguments over the cause of the failures, ranging from improper installation, unbalanced and/or excess force to poor design and insufficient material strength, have been disputed between the contractor and the government engineers. Incipient melting during solution treatment was also suspected as one of the reasons responsible for cracking in the original aluminum castings. This study compared the microstructures of as-cast and heat-treated samples and concluded that incipient melting did not occur during solution treatment and thus was not the principal cause for cracking in the aluminum castings. Eventually, the light aluminum alloy was replaced by a heavier but stronger ductile iron. As a result, the durability of the QRSA trunnion casting has been significantly improved and the deficiency was remedied.

  9. Prediction of ALLOY SHRINKAGE FACTORS FOR THE INVESTMENT CASTING PROCESS

    SciTech Connect

    Sabau, Adrian S

    2006-01-01

    This study deals with the experimental measurements and numerical predictions of alloy shrinkage factors (SFs) related to the investment casting process. The dimensions of the A356 aluminum alloy casting were determined from the numerical simulation results of solidification, heat transfer, fluid dynamics, and deformation phenomena. The investment casting process was carried out using wax patterns of unfilled wax and shell molds that were made of fused silica with a zircon prime coat. The dimensions of the die tooling, wax pattern, and casting were measured, in order to determine the actual tooling allowances. Several numerical simulations were carried out, to assess the level of accuracy for the casting shrinkage. The solid fraction threshold, at which the transition from the fluid dynamics to the solid dynamics occurs, was found to be important in predicting shrinkage factors (SFs). It was found that accurate predictions were obtained for all measued dimensions when the shell mold was considered a deformable material.

  10. Relationship Between Casting Distortion, Mold Filling, and Interfacial Heat Transfer in Sand Molds

    SciTech Connect

    J. K. Parker; K. A. Woodbury; T. S. Piwonka; Y. Owusu

    1999-09-30

    This project sought to determine the relationship between casting dimensions and interfacial heat transfer in aluminum alloy sand castings. The program had four parts; measurement of interfacial heat transfer coefficients in resin bonded and green sand molds, the measurement of gap formation in these molds, the analysis of castings made in varying gatings, orientations and thicknesses, and the measurement of residual stresses in castings in the as-cast and gate removed condition. New values for interfacial heat transfer coefficients were measured, a novel method for gap formation was developed, and the variation of casting dimensions with casting method, gating, and casting orientation in the mold was documented.

  11. The Influence of Casting Conditions on the Microstructure of As-Cast U-10Mo Alloys: Characterization of the Casting Process Baseline

    SciTech Connect

    Nyberg, Eric A.; Joshi, Vineet V.; Lavender, Curt A.; Paxton, Dean M.; Burkes, Douglas

    2013-12-13

    Sections of eight plate castings of uranium alloyed with 10 wt% molybdenum (U-10Mo) were sent from Y-12 to the Pacific Northwest National Laboratory (PNNL) for microstructural characterization. This report summarizes the results from this study.

  12. Cast Stone Formulation At Higher Sodium Concentrations

    SciTech Connect

    Fox, K. M.; Roberts, K. A.; Edwards, T. B.

    2014-02-28

    A low temperature waste form known as Cast Stone is being considered to provide supplemental Low Activity Waste (LAW) immobilization capacity for the Hanford site. Formulation of Cast Stone at high sodium concentrations is of interest since a significant reduction in the necessary volume of Cast Stone and subsequent disposal costs could be achieved if an acceptable waste form can be produced with a high sodium molarity salt solution combined with a high water to premix (or dry blend) ratio. The objectives of this study were to evaluate the factors involved with increasing the sodium concentration in Cast Stone, including production and performance properties and the retention and release of specific components of interest. Three factors were identified for the experimental matrix: the concentration of sodium in the simulated salt solution, the water to premix ratio, and the blast furnace slag portion of the premix. The salt solution simulants used in this study were formulated to represent the overall average waste composition. The cement, blast furnace slag, and fly ash were sourced from a supplier in the Hanford area in order to be representative. The test mixes were prepared in the laboratory and fresh properties were measured. Fresh density increased with increasing sodium molarity and with decreasing water to premix ratio, as expected given the individual densities of these components. Rheology measurements showed that all of the test mixes produced very fluid slurries. The fresh density and rheology data are of potential value in designing a future Cast Stone production facility. Standing water and density gradient testing showed that settling is not of particular concern for the high sodium compositions studied. Heat of hydration measurements may provide some insight into the reactions that occur within the test mixes, which may in turn be related to the properties and performance of the waste form. These measurements showed that increased sodium concentration in the salt solution reduced the time to peak heat flow, and reducing the amount of slag in the premix increased the time to peak heat flow. These observations may help to describe some of the cured properties of the samples, in particular the differences in compressive strength observed after 28 and 90 days of curing. Samples were cured for at least 28 days at ambient temperature in the laboratory prior to cured properties analyses. The low activity waste form for disposal at the Hanford Site is required to have a compressive strength of at least 500 psi. After 28 days of curing, several of the test mixes had mean compressive strengths that were below the 500 psi requirement. Higher sodium concentrations and higher water to premix ratios led to reduced compressive strength. Higher fly ash concentrations decreased the compressive strength after 28 days of curing. This may be explained in that the cementitious phases matured more quickly in the mixes with higher concentrations of slag, as evidenced by the data for the time to peak heat generation. All of the test mixes exhibited higher mean compressive strengths after 90 days of curing, with only one composition having a mean compressive strength of less than 500 psi. Leachability indices were determined for the test mixes for contaminants of interest. The leaching performance of the mixes evaluated in this study was not particularly sensitive to the factors used in the experimental design. This may be beneficial in demonstrating that the performance of the waste form is robust with respect to changes in the mix composition. The results of this study demonstrate the potential to achieve significantly higher waste loadings in Cast Stone and other low temperature, cementitious waste forms. Additional work is needed to elucidate the hydration mechanisms occurring in Cast Stone formulated with highly concentrated salt solutions since these reactions are responsible for determining the performance of the cured waste form. The thermal analyses completed in this study provide some preliminary insight, although the limited range of the factors in the test matrix hindered the identification of individual component effects. Future work should involve broader factor ranges to identify the roles played by each of the components in the mix via thermal analyses, analytical microscopy, and characterization of phase formation.

  13. Cast Stone Formulation At Higher Sodium Concentrations

    SciTech Connect

    Fox, K. M.; Edwards, T. A.; Roberts, K. B.

    2013-10-02

    A low temperature waste form known as Cast Stone is being considered to provide supplemental Low Activity Waste (LAW) immobilization capacity for the Hanford site. Formulation of Cast Stone at high sodium concentrations is of interest since a significant reduction in the necessary volume of Cast Stone and subsequent disposal costs could be achieved if an acceptable waste form can be produced with a high sodium molarity salt solution combined with a high water to premix (or dry blend) ratio. The objectives of this study were to evaluate the factors involved with increasing the sodium concentration in Cast Stone, including production and performance properties and the retention and release of specific components of interest. Three factors were identified for the experimental matrix: the concentration of sodium in the simulated salt solution, the water to premix ratio, and the blast furnace slag portion of the premix. The salt solution simulants used in this study were formulated to represent the overall average waste composition. The cement, blast furnace slag, and fly ash were sourced from a supplier in the Hanford area in order to be representative. The test mixes were prepared in the laboratory and fresh properties were measured. Fresh density increased with increasing sodium molarity and with decreasing water to premix ratio, as expected given the individual densities of these components. Rheology measurements showed that all of the test mixes produced very fluid slurries. The fresh density and rheology data are of potential value in designing a future Cast Stone production facility. Standing water and density gradient testing showed that settling is not of particular concern for the high sodium compositions studied. Heat of hydration measurements may provide some insight into the reactions that occur within the test mixes, which may in turn be related to the properties and performance of the waste form. These measurements showed that increased sodium concentration in the salt solution reduced the time to peak heat flow, and reducing the amount of slag in the premix increased the time to peak heat flow. These observations may help to describe some of the cured properties of the samples, in particular the differences in compressive strength observed after 28 and 90 days of curing. Samples were cured for at least 28 days at ambient temperature in the laboratory prior to cured properties analyses. The low activity waste form for disposal at the Hanford Site is required to have a compressive strength of at least 500 psi. After 28 days of curing, several of the test mixes had mean compressive strengths that were below the 500 psi requirement. Higher sodium concentrations and higher water to premix ratios led to reduced compressive strength. Higher fly ash concentrations decreased the compressive strength after 28 days of curing. This may be explained in that the cementitious phases matured more quickly in the mixes with higher concentrations of slag, as evidenced by the data for the time to peak heat generation. All of the test mixes exhibited higher mean compressive strengths after 90 days of curing, with only one composition having a mean compressive strength of less than 500 psi. Leach indices were determined for the test mixes for contaminants of interest. The leaching performance of the mixes evaluated in this study was not particularly sensitive to the factors used in the experimental design. This may be beneficial in demonstrating that the performance of the waste form is robust with respect to changes in the mix composition. The results of this study demonstrate the potential to achieve significantly higher waste loadings in Cast Stone and other low temperature, cementitious waste forms. Additional work is needed to elucidate the hydration mechanisms occurring in Cast Stone formulated with highly concentrated salt solutions since these reactions are responsible for determining the performance of the cured waste form. The thermal analyses completed in this study provide some preliminary insight, although the limited range of the factors in the test matrix hindered the identification of individual component effects. Future work should involve broader factor ranges to identify the roles played by each of the components in the mix via thermal analyses, analytical microscopy, and characterization of phase formation.

  14. Cast Stone Formulation At Higher Sodium Concentrations

    SciTech Connect

    Fox, K. M.; Roberts, K. A.; Edwards, T. B.

    2013-09-17

    A low temperature waste form known as Cast Stone is being considered to provide supplemental Low Activity Waste (LAW) immobilization capacity for the Hanford site. Formulation of Cast Stone at high sodium concentrations is of interest since a significant reduction in the necessary volume of Cast Stone and subsequent disposal costs could be achieved if an acceptable waste form can be produced with a high sodium molarity salt solution combined with a high water to premix (or dry blend) ratio. The objectives of this study were to evaluate the factors involved with increasing the sodium concentration in Cast Stone, including production and performance properties and the retention and release of specific components of interest. Three factors were identified for the experimental matrix: the concentration of sodium in the simulated salt solution, the water to premix ratio, and the blast furnace slag portion of the premix. The salt solution simulants used in this study were formulated to represent the overall average waste composition. The cement, blast furnace slag, and fly ash were sourced from a supplier in the Hanford area in order to be representative. The test mixes were prepared in the laboratory and fresh properties were measured. Fresh density increased with increasing sodium molarity and with decreasing water to premix ratio, as expected given the individual densities of these components. Rheology measurements showed that all of the test mixes produced very fluid slurries. The fresh density and rheology data are of potential value in designing a future Cast Stone production facility. Standing water and density gradient testing showed that settling is not of particular concern for the high sodium compositions studied. Heat of hydration measurements may provide some insight into the reactions that occur within the test mixes, which may in turn be related to the properties and performance of the waste form. These measurements showed that increased sodium concentration in the salt solution reduced the time to peak heat flow, and reducing the amount of slag in the premix increased the time to peak heat flow. These observations may help to describe some of the cured properties of the samples, in particular the differences in compressive strength observed after 28 and 90 days of curing. Samples were cured for at least 28 days at ambient temperature in the laboratory prior to cured properties analyses. The low activity waste form for disposal at the Hanford Site is required to have a compressive strength of at least 500 psi. After 28 days of curing, several of the test mixes had mean compressive strengths that were below the 500 psi requirement. Higher sodium concentrations and higher water to premix ratios led to reduced compressive strength. Higher fly ash concentrations decreased the compressive strength after 28 days of curing. This may be explained in that the cementitious phases matured more quickly in the mixes with higher concentrations of slag, as evidenced by the data for the time to peak heat generation. All of the test mixes exhibited higher mean compressive strengths after 90 days of curing, with only one composition having a mean compressive strength of less than 500 psi. Leach indices were determined for the test mixes for contaminants of interest. The leaching performance of the mixes evaluated in this study was not particularly sensitive to the factors used in the experimental design. This may be beneficial in demonstrating that the performance of the waste form is robust with respect to changes in the mix composition. The results of this study demonstrate the potential to achieve significantly higher waste loadings in Cast Stone and other low temperature, cementitious waste forms. Additional work is needed to elucidate the hydration mechanisms occurring in Cast Stone formulated with highly concentrated salt solutions since these reactions are responsible for determining the performance of the cured waste form. The thermal analyses completed in this study provide some preliminary insight, although the limited range of the factors in the test matrix hindered the identification of individual component effects. Future work should involve broader factor ranges to identify the roles played by each of the components in the mix via thermal analyses, analytical microscopy, and characterization of phase formation.

  15. Gating of Permanent Molds for Aluminum Casting

    SciTech Connect

    David Schwam; John F. Wallace; Tom Engle; Qingming Chang

    2004-01-01

    This report summarizes a two-year project, DE-FC07-011D13983 that concerns the gating of aluminum castings in permanent molds. The main goal of the project is to improve the quality of aluminum castings produced in permanent molds. The approach taken was to determine how the vertical type gating systems used for permanent mold castings can be designed to fill the mold cavity with a minimum of damage to the quality of the resulting casting. It is evident that somewhat different systems are preferred for different shapes and sizes of aluminum castings. The main problems caused by improper gating are entrained aluminum oxide films and entrapped gas. The project highlights the characteristic features of gating systems used in permanent mold aluminum foundries and recommends gating procedures designed to avoid common defects. The study also provides direct evidence on the filling pattern and heat flow behavior in permanent mold castings. Equipment and procedure for real time X-Ray radiography of molten aluminum flow into permanent molds have been developed. Other studies have been conducted using water flow and behavior of liquid aluminum in sand mold using real time photography. This investigation utilizes graphite molds transparent to X-Rays making it possible to observe the flow pattern through a number of vertically oriented grating systems. These have included systems that are choked at the base of a rounded vertical sprue and vertical gating systems with a variety of different ingates into the bottom of a mold cavity. These systems have also been changed to include gating systems with vertical and horizontal gate configurations. Several conclusions can be derived from this study. A sprue-well, as designed in these experiments, does not eliminate the vena contracta. Because of the swirling at the sprue-base, the circulating metal begins to push the entering metal stream toward the open runner mitigating the intended effect of the sprue-well. Improved designs of sprue-wells should be evaluated. In order for a runner extension to operate efficiently, it must have a small squared cross-section. If it is tapered, the first metal to enter the first metal to enter the system is not effectively trapped. If the cross section is large, there is less turbulence when the aluminum enters the mold cavity in comparison to the smaller cross sectioned, squared runner. However, a large runner reduces yield. In bottom-feeding gating systems, a filter can significantly improve the filling of the casting. The filter helps to slow the metal flow rate enough to reduce jetting into the mold cavity. In top feeding gating systems, a filter can initially slow the metal flow rate, but because the metal drops after passing the filter, high velocities are achieved during free fall when a filter is in place. Side feeding gating systems provide less turbulent flow into the mold cavity. The flow is comparable to a bottom-feeding gating system with a filter. Using properly designed side-gating system instead of a bottom-feeding system with a filter can potentially save the cost of the filter. Rough coatings promote better fill than smooth coatings. This conclusion seems at first counter intuitive. One tends to assume a rough coating creates more friction resistance to the flow of molten metal. In actuality the molten aluminum stream flows inside an oxide film envelope. When this film rests on top of the ridges of a rough coating the microscopic air pockets between the coating and the oxide film provide more thermal insulation than in a smooth coating. This insulation promotes longer feeding distances in the mold as demonstrated in the experiments. Much of this work is applicable to vertically parted sand molds as well, although the heat transfer conditions do vary from a metal mold generally used in permanent molding of aluminum. The flow measurements were conducted using graphite molds and real time X-Ray radiography recorded at a rate of 30 images per second through those molds. The facilities at Arrow Aluminum Foundry were used in the study. The results will be employed to demonstrate to the American Foundry Industry how molten aluminum flows in permanent molds of different designs and characteristics. The results of these experiments were compared with computer mold and simulation models. The Procast and Magmasoft flow and solidification simulation programs were employed to predict the flow behavior under the different conditions that can prevail in permanent mold gating. The development of a valid computer model that can correctly and accurately predict this flow is much more intricate than generally realized. To provide accurate predictions such programs require significant adjustments and verification with experimental data.

  16. Methods and apparatuses for manufacturing geometric multicrystalline cast silicon and geometric multicrystalline cast silicon bodies for photovoltaics

    DOEpatents

    Stoddard, Nathan G

    2015-02-10

    Methods and apparatuses are provided for casting silicon for photovoltaic cells and other applications. With such methods and apparatuses, a cast body of geometrically ordered multi-crystalline silicon may be formed that is free or substantially free of radially-distributed impurities and defects and having at least two dimensions that are each at least about 10 cm is provided.

  17. Marked Calpastatin (CAST) Depletion in Alzheimers Disease Accelerates Cytoskeleton Disruption and Neurodegeneration: Neuroprotection by CAST Overexpression

    PubMed Central

    Rao, Mala V.; Mohan, Panaiyur S.; Peterhoff, Corrinne M.; Yang, Dun-Sheng; Schmidt, Stephen D.; Stavrides, Philip H.; Campbell, Jabbar; Chen, Yuanxin; Jiang, Ying; Paskevich, Peter A.; Cataldo, Anne M.; Haroutunian, Vahram; Nixon, Ralph A.

    2010-01-01

    Increased activity of calpains is implicated in synaptic dysfunction and neurodegeneration in Alzheimers disease (AD). The molecular mechanisms responsible for increased calpain activity in AD are not known. Here, we demonstrate that disease progression is propelled by a marked depletion of the endogenous calpain inhibitor, calpastatin (CAST), from AD neurons, which is mediated by caspase-1, caspase-3, and calpains. Initial CAST depletion focally along dendrites coincides topographically with calpain II and ERK 1/2 activation, tau cleavage by caspase-3, and tau and neurofilament hyperphosphorylation. These same changes, together with cytoskeletal proteolysis and neuronal cell death, accompany CAST depletion after intrahippocampal kainic acid administration to mice, and are substantially reduced in mice overexpressing human CAST. Moreover, CAST reduction by shRNA in neuronal cells causes calpain-mediated death at levels of calcium-induced injury that are sublethal to cells normally expressing CAST. Our results strongly support a novel hypothesis that CAST depletion by multiple abnormally activated proteases accelerates calpain dysregulation in AD leading to cytoskeleton disruption and neurodegeneration. CAST mimetics may, therefore, be neuroprotective in AD. PMID:19020018

  18. Development of low-temperature high-strength integral steel castings for offshore construction by casting process engineering

    NASA Astrophysics Data System (ADS)

    Lim, Sang-Sub; Mun, Jae-Chul; Kim, Tae-Won; Kang, Chung-Gil

    2014-12-01

    In casting steels for offshore construction, manufacturing integral casted structures to prevent fatigue cracks in the stress raisers is superior to using welded structures. Here, mold design and casting analysis were conducted for integral casting steel. The laminar flow of molten metal was analyzed and distributions of hot spots and porosities were studied. A prototype was subsequently produced, and air vents were designed to improve the surface defects caused by the release of gas. A radiographic test revealed no internal defects inside the casted steel. Evaluating the chemical and mechanical properties of specimens sampled from the product revealed that target values were quantitatively satisfied. To assess weldability in consideration of repair welding, the product was machined with grooves and welded, after which the mechanical properties of hardness as well as tensile, impact, and bending strengths were evaluated. No substantive differences were found in the mechanical properties before and after welding.

  19. TiC reinforced cast Cr steels

    SciTech Connect

    Dogan, O.N.; Hawk, J.A.; Schrems, K.K.

    2006-06-01

    A new class of materials, namely TiC-reinforced cast chromium (Cr) steels, was developed for applications requiring high abrasion resistance and good fracture toughness. The research approach was to modify the carbide structure of commercial AISI 440C steel for better fracture resistance while maintaining the already high abrasion resistance. The new alloys contained 12Cr, 2.54.5Ti, and 11.5C (wt.%) and were melted in a vacuum induction furnace. Their microstructure was composed primarily of a martensitic matrix with a dispersion of TiC precipitates. Modification of TiC morphology was accomplished through changing the cooling rate during solidification. Wear rates of the TiC-reinforced Cr steels were comparable to that of AISI 440C steel, but the impact resistance was much improved.

  20. General requirement for effective overburden casting

    SciTech Connect

    Cook, J.D.; McCutchen, D.

    1994-12-31

    Effective overburden casting requires the efficient use of todays explosives and initiations systems if a mine is to survive. This paper uses a major coal stripping operation as an example of the proper application of explosives and initiation system to their conditions. High speed photography, rock analysis and computer modeling were used to assist in determining the effective use of the explosives and the initiation systems. The high speed photography confirmed the computer modeling done by SABREX, the Scientific Approach to Blasting Rock with Explosives developed by ICI Explosives world group of companies. The major coal company used in this paper mines the 36 inch Sewanee coal seam in Tennessee for TVA steam generation. The overburden is usually in excess of 100 ft. of sandstone.

  1. Casting inorganic structures with DNA molds

    PubMed Central

    Sun, Wei; Boulais, Etienne; Hakobyan, Yera; Wang, Wei Li; Guan, Amy; Bathe, Mark; Yin, Peng

    2014-01-01

    We report a general strategy for designing and synthesizing inorganic nanostructures with arbitrarily prescribed three-dimensional shapes. Computationally designed DNA strands self-assemble into a stiff “nano-mold” that contains a user-specified three-dimensional cavity and encloses a nucleating gold “seed”. Under mild conditions, this seed grows into a larger cast structure that fills and thus replicates the cavity. We synthesized a variety of nanoparticles with three nanometer resolution: three distinct silver cuboids with three independently tunable dimensions, silver and gold nanoparticles with diverse cross sections, and composite structures with homo-/heterogeneous components. The designer equilateral silver triangular and spherical nanoparticles exhibited plasmonic properties consistent with electromagnetism-based simulations. Our framework is generalizable to more complex geometries and diverse inorganic materials, offering a range of applications in biosensing, photonics, and nanoelectronics. PMID:25301973

  2. Method of casting silicon into thin sheets

    DOEpatents

    Sanjurjo, Angel (San Jose, CA); Rowcliffe, David J. (Los Altos, CA); Bartlett, Robert W. (Tucson, AZ)

    1982-10-26

    Silicon (Si) is cast into thin shapes within a flat-bottomed graphite crucible by providing a melt of molten Si along with a relatively small amount of a molten salt, preferably NaF. The Si in the resulting melt forms a spherical pool which sinks into and is wetted by the molten salt. Under these conditions the Si will not react with any graphite to form SiC. The melt in the crucible is pressed to the desired thinness with a graphite tool at which point the tool is held until the mass in the crucible has been cooled to temperatures below the Si melting point, at which point the Si shape can be removed.

  3. Strength of tape cast and laminated ceramics

    SciTech Connect

    Ham-Su, R.; Wilkinson, D.S.

    1995-06-01

    Monolithic Al{sub 2}O{sub 3} ceramic laminates were fabricated via a tape casting process. The strength of the single tapes was compared with that of laminates, using biaxial flexure tests. The fracture stress was similar. However, the laminates presented a lower Weibull modulus. The feasibility of eliminating or diminishing void-type flaws present in the green tapes was also assessed. To this end, tapes were first punctured, then laminated and sintered, and the effect of these known flaws in the final ceramic was assessed in four-point flexure tests. The thermocompression of green tapes during laminate fabrication was found to modify the flaws to a more forgiving morphology.

  4. CENTER FOR ADVANCED SEPARATION TECHNOLOGY (CAST) PROGRAM

    SciTech Connect

    Yoon, Roe-Hoan; Hull, Christopher

    2014-09-30

    The U.S. is the largest producer of mining products in the world. In 2011, U.S. mining operations contributed a total of $232 billion to the nation’s GDP plus $138 billion in labor income. Of this the coal mining industry contributed a total of $97.5 billion to GDP plus $53 billion in labor income. Despite these contributions, the industry has not been well supported with research and development funds as compared to mining industries in other countries. To overcome this problem, the Center for Advanced Separation Technologies (CAST) was established to develop technologies that can be used by the U.S. mining industry to create new products, reduce production costs, and meet environmental regulations.

  5. Spin-cast carbon films from polyacrylonitrile

    SciTech Connect

    Renschler, C.L.; Sylwester, A.P.

    1987-01-01

    Carbon films have been made by a variety of techniques, including evaporation, sputtering, and laser or thermal pyrolysis of organic polymers. Polyacrylonitrile (PAN) is often used as a carbon precursor, since low-temperature thermo-oxidative pretreatment produces a material which can be pyrolyzed without loss of shape. This is the basis for the production of carbon fibers with good mechanical properties. We report here the formation of very thin films of carbon (500 to 1500 A) by pyrolysis of spin-cast PAN. Using this technique, large, conductive films can be made which are sufficiently robust to allow intact lift-off and transfer of the films from one substrate to another. Such films are chemically inert, but can be photolithographically patterned and etched with an oxygen plasma.

  6. Casting of HgCdTe

    NASA Astrophysics Data System (ADS)

    Alexiades, V.

    1991-03-01

    Mercury-Cadmium-Telluride is a technologically important electronic material, used primarily as an infrared-detector. In such applications, large crystals of uniform concentration are desirable, which is difficult to achieve when the crystal is grown under gravity. Modeling and numerical simulation can help us gain insight, in the interpretation of experiments, and in designing future earth-bound and microgravity experiments. In this report we present a compilation of the relevant thermophysical properties of the pseudo-binary (HgTe)(1-x)(CdTe)(x), as functions of composition, x, and temperature, for both the solid and liquid phases, at the high temperatures (approximately 600 to 1100 C) relevant in the casting process.

  7. Acoustic energy transmission in cast iron pipelines

    NASA Astrophysics Data System (ADS)

    Kiziroglou, Michail E.; Boyle, David E.; Wright, Steven W.; Yeatman, Eric M.

    2015-12-01

    In this paper we propose acoustic power transfer as a method for the remote powering of pipeline sensor nodes. A theoretical framework of acoustic power propagation in the ceramic transducers and the metal structures is drawn, based on the Mason equivalent circuit. The effect of mounting on the electrical response of piezoelectric transducers is studied experimentally. Using two identical transducer structures, power transmission of 0.33 mW through a 1 m long, 118 mm diameter cast iron pipe, with 8 mm wall thickness is demonstrated, at 1 V received voltage amplitude. A near-linear relationship between input and output voltage is observed. These results show that it is possible to deliver significant power to sensor nodes through acoustic waves in solid structures. The proposed method may enable the implementation of acoustic - powered wireless sensor nodes for structural and operation monitoring of pipeline infrastructure.

  8. Near-congruent solidification of castings

    NASA Astrophysics Data System (ADS)

    Chaput, Kevin J.

    A study on the microstructure development of as-cast Cu-Mn alloys based around the congruent minimum at 34.6 wt % Mn and 873 °C was performed. Initially, this was to evaluate the alloy as an alternative to wide freezing range Pb and Sn bronzes that are plagued with porosity. The shallow minimum and associated narrow freezing ranges around the congruent point result in a completely cellular (non-dendritic) solidification morphology for a composition range ~3 wt % Mn about the congruent composition (C c). The degree of cellular solidification was found to depend on the mold material. Increased mold conductivity lead to a narrower composition range of complete cellular solidification. By casting alloys of different compositions into a composite mold, the effect of the mold conductivity allowed an evaluation of the congruent point reported by Gokcen. These results fit well with the constitutional supercooling criterion. While solidification at a point ideally would be planar, this was not observed even with minor deviations from the Cc. An additional study of the microstructure development along the minimum trough in the liquidus surface between the Cu-Mn and Ni-Mn binary congruent points of the Cu-Mn-Ni ternary system was conducted. This study revealed that alloys near the binary congruent minima were more cellular than alloys near the middle of the phase diagram, along the trough. As the composition approached the center of the Cu-Mn-Ni diagram, the morphology became more dendritic, characteristic of an isomorphous system. Even though these alloys did not solidify in a completely cellular manner, they were free of any microshrinkage porosity. The alloys in this study (Cu-Mn and Cu-Mn-Ni) show promise for use in structural applications due to the lack of microshrinkage porosity, potent solution strengthening of manganese and strong aging response.

  9. Thermal investigation of compound cast steel tools

    NASA Astrophysics Data System (ADS)

    Schaper, Mirko; Haferkamp, Heinz; Niemeyer, Matthias; Pelz, Christoph; Viets, Roman

    1999-03-01

    Tools for hot forging are exposed to complex stresses during their life-cycle. Therefore, forging dies should have a high wear resistance and toughness on the surface, combined with excellent thermal conductivity in the die body. Hot-work tool steel is appropriate for this application except from its thermal conductance. Hence, a tool consisting of hot-work tool steel in the area of contact and heat-treatable steel as die body is favorable. A smoothly graded microstructure in the joint zone between the two steel alloys is needed to match with the requirements. Fabrication of such functionally graded dies by sand casting exhibits high sensitivity to temperature and geometry dependent parameters. To melt on the inlay's surface must be ensured without destroying this region according to overheat coarsening and mixing of alloying elements. Instead of empirical methods to optimize the process parameters, a thermographic CCD-device is used for visualization of the heat flow while pouring the melt on the inlay. In fact the molten metal flow can be directed homogeneously across the bonding surface at adequate temperatures after evaluation of thermography data. The use of a silica-aerogel sheet as opaque window beneath the inlay in the mold enables systematic development of gating and risering, whereas undesirable scaling of the inlay due to the change of emissivity is retarded. Infrared image sequences clearly demonstrate the influence of different ring gating systems concerning the filling properties. Non-joined cavities may even be classified from image data. Compound cast steel tools have been manufactured and examined in forging trials validating life-cycle prolongation.

  10. Directional solidification of white cast iron

    SciTech Connect

    Park, J.S.; Verhoeven, J.D. |

    1996-08-01

    Several studies of the ledeburite eutectic (Fe-Fe{sub 3}C), in pure Fe-C alloys have shown that it has a lamellar morphology under plane front growth conditions. The structure of ledeburite in white cast irons, Fe-C-is, consists of a rod morphology. It is generally not possible to produce plane front growth of Fe-C-Si eutectic alloys in the Fe-Fe{sub 3}C form, because at the slow growth rates required for plane front growth, the Fe{sub 3}C phase is replaced by graphite. By using small additions of Te, the growth of graphite was suppressed, and the plane front growth of the ledeburite eutectic in Fe-C-Si alloys was carried out with Si levels up to 1 wt pct. It was found that the growth morphology became a faceted rod morphology at 1 wt pct Si, but in contrast to the usual rod morphology of white cast irons, the rod phase was Fe{sub 3}C rather than iron. It was shown that the usual rod morphology only forms at the sides of the two-phase cellular or dendritic growth fronts in Fe-C-Si alloys. Possible reasons for the inability of plane front directional solidification to produce the usual rod morphology in Fe-C-Si alloys are discussed. Also, data are presented on the spacing of the lamellar eutectic in pure Fe-C ledeburite, which indicates that this system does not follow the usual {lambda}{sup 2}V = constant relation of regular eutectics.

  11. Drug release mechanisms of cast lipid implants.

    PubMed

    Kreye, F; Siepmann, F; Willart, J F; Descamps, M; Siepmann, J

    2011-08-01

    The aim of this work was to better understand which physicochemical processes are involved in the control of drug release from lipid implants prepared by melting and casting. Lipid implants gain steadily in importance as controlled parenteral drug delivery systems: In contrast to PLGA-based devices, no acidic microclimates are created, which can inactivate incorporated drugs. The melting and casting method offers various advantages over the commonly used direct compression technique. For example, powder de-mixing during manufacturing and highly challenging scale-up due to poor powder flowability are avoided. Importantly, broad spectra of drug release patterns can be easily provided by varying the type of lipid. The resulting drug release rates are generally lower than those of implants prepared by direct compression. This is probably due to the differences in the microstructure of the pore network of the systems. Drug or water diffusion plays a dominant role for the control of drug release, potentially combined with limited drug solubility effects, caused by the low amounts of water available within the implants. In the case of pure diffusion control, a mechanistic realistic mathematical theory is proposed, which allows for quantitative predictions of the effects of formulation parameters on the resulting drug release kinetics. Importantly, these theoretical predictions could be successfully confirmed by independent experiments. Thus, the obtained new insight into the underlying drug release mechanisms can significantly facilitate the optimization of this type of advanced drug delivery systems. This is particularly helpful if long release periods are targeted, requiring time-consuming experimental studies. PMID:21352913

  12. Melting and casting characteristics of aluminum alloy A356-SiC particulate reinforced cast composites

    SciTech Connect

    Yarandi, F.M.

    1991-01-01

    Melting and casting characteristics of A356 (Al 7% Si) alloy reinforced with 10, 15, and 20 vol. % SiC particles were studied. Remelting followed by holding and solidification of these composites leads to settling of the SiC particles to the bottom of the mold. The height of the SiC particle-free zone formed at the top of the mold, as a result of settling, is referred to as the denuded zone. A356 with 20 vol. % SiC ({approximately}14-{mu} particle size) showed larger denuded zones for a given settling time compared to the system with 10 or 15 vol. % SiC. The permanent mold and sand mold spiral fluidities, and permanent mold casting fluidity of Al A356-SiC particle melt slurry generally decrease with increasing vol. % of a given size SiC. The fluidity values increase with temperature until a temperature range of 740-760C. Solidification microstructures formed during static settling and during flow along the length of the casting fluidity for SiC particle composites were analyzed. Influences of cooling rate, settling time, and oxide films on solidification microstructures were investigated.

  13. Irradiation response of delta ferrite in as-cast and thermally aged cast stainless steel

    NASA Astrophysics Data System (ADS)

    Li, Zhangbo; Lo, Wei-Yang; Chen, Yiren; Pakarinen, Janne; Wu, Yaqiao; Allen, Todd; Yang, Yong

    2015-11-01

    To enable the life extension of Light Water Reactors (LWRs) beyond 60 years, it is critical to gain adequate knowledge for making conclusive predictions to assure the integrity of duplex stainless steel reactor components, e.g. primary pressure boundary and reactor vessel internal. Microstructural changes in the ferrite of thermally aged, neutron irradiated only, and neutron irradiated after being thermally aged cast austenitic stainless steels (CASS) were investigated using atom probe tomography. The thermal aging was performed at 400C for 10,000h and the irradiation was conducted in the Halden reactor at ?315C to 0.08 dpa (5.6נ1019n/cm2, E>1MeV). Low dose neutron irradiation at a dose rate of 5נ10-9dpa/s was found to induce spinodal decomposition in the ferrite of as-cast microstructure, and further to enhance the spinodal decomposition in the thermally aged cast alloys. Regarding the G-phase precipitates, the neutron irradiation dramatically increases the precipitate size, and alters the composition of the precipitates with increased, Mn, Ni, Si and Mo and reduced Fe and Cr contents. The results have shown that low dose neutron irradiation can further accelerate the degradation of ferrite in a duplex stainless steel at the LWR relevant condition.

  14. The influence of master cast technique on the cast precision of implant-retained fixed prostheses.

    PubMed

    Rodrigues, Mariana Agustinho; Luthi, Leonardo Flores; Henriques, Guilherme Elias Pessanha

    2012-01-01

    The aim of this study was to evaluate the precision of three different mold filling techniques in order to obtain a cast simulating a three-unit, implant-retained, fixed prosthesis. Thirty casts (n = 10) were obtained using three different mold filling techniques. Group 1 used a unique fulfillment technique, Group 2 used a two-step fulfillment technique, and Group 3 used a latex cylinder technique. Using a metallic matrix, a titanium substructure was created to simulate a three-unit fixed prosthesis used as reference to evaluate the marginal misfit and tension forces in each cast. The vertical misfit was measured by an optical microscope with an increase of 120X and by an analysis unit using the one-screw test. The tension was quantified using strain gauges. The strain results showed a statistical difference between Group 3 and the other groups. The Tukey test showed no difference between the different treatment groups (p = 0.05). All three techniques were deemed efficient; however, considering that the cylinder latex technique induced less force toward the implants, it is the preferable technique for daily clinical practice. PMID:22414505

  15. Development of a CFD code for casting simulation

    NASA Technical Reports Server (NTRS)

    Murph, Jesse E.

    1993-01-01

    Because of high rejection rates for large structural castings (e.g., the Space Shuttle Main Engine Alternate Turbopump Design Program), a reliable casting simulation computer code is very desirable. This code would reduce both the development time and life cycle costs by allowing accurate modeling of the entire casting process. While this code could be used for other types of castings, the most significant reductions of time and cost would probably be realized in complex investment castings, where any reduction in the number of development castings would be of significant benefit. The casting process is conveniently divided into three distinct phases: (1) mold filling, where the melt is poured or forced into the mold cavity; (2) solidification, where the melt undergoes a phase change to the solid state; and (3) cool down, where the solidified part continues to cool to ambient conditions. While these phases may appear to be separate and distinct, temporal overlaps do exist between phases (e.g., local solidification occurring during mold filling), and some phenomenological events are affected by others (e.g., residual stresses depend on solidification and cooling rates). Therefore, a reliable code must accurately model all three phases and the interactions between each. While many codes have been developed (to various stages of complexity) to model the solidification and cool down phases, only a few codes have been developed to model mold filling.

  16. Columnar to equiaxed transition in high Cr white iron castings

    SciTech Connect

    Dogan, O.N.

    1996-07-15

    White cast irons are frequently used in applications requiring high wear resistance. High Cr white cast irons have a composite microstructure composed of hard (Fe,Cr){sub 7}C{sub 3} carbides in a steel matrix. In thick section castings, long rod-shaped carbides may grow perpendicular to the mold wall to form the columnar zone of the casting, or their long axes may grow in random directions to form equiaxed grains. Previous research has indicated that the equiaxed region of these high Cr white iron castings is much more wear resistant under high stress abrasive conditions than the columnar region, when the carbides are oriented perpendicular to the wear surface. Therefore, in order to maximize their abrasion resistance, it is essential that wear resistant cast parts with thick sections be produced with completely equiaxed macrostructures to maximize their abrasion resistance. In the present study, the effect of both the chemical composition, particularly carbon content, and the pouring superheat of the melt on the macrostructure of high Cr white iron castings is investigated.

  17. Development of a thin steel strip casting process. Final report

    SciTech Connect

    Williams, R.S.

    1994-04-01

    This is a comprehensive effort to develop direct strip casting to the point where a pilot scale program for casting carbon steel strip could be initiated. All important aspects of the technology were being investigated, however the program was terminated early due to a change in the business strategy of the primary contractor, Armco Inc. (focus to be directed at specialty steels, not low carbon steel). At termination, the project was on target on all milestones and under budget. Major part was casting of strip at the experiment casting facility. A new caster, capable of producing direct cast strip of up to 12 in. wide in heats of 1000 and 3000 lb, was used. A total of 81 1000-1200 lb heats were cast as well as one test heat of 3000 lb. Most produced strip of from 0.016 to 0.085 in. thick. Process reliability was excellent for short casting times; quality was generally poor from modern hot strip mill standards, but the practices necessary for good surface quality were identified.

  18. A study of interfacial heat transfer and process parameters in squeeze casting and low pressure permanent mold casting

    NASA Astrophysics Data System (ADS)

    Krishna, Prasad

    2001-08-01

    With the emerging demand for energy efficient and environment-friendly automobiles, cast aluminum alloys are increasingly being used in their manufacture. In this context, two permanent mold casting processes, namely, Squeeze Cast Permanent Mold and Low Pressure Permanent Mold (LPPM) have become very popular in the production of high integrity shape-cast aluminum components. However, many industries are yet to benefit from the full potential of these processes due to limited understanding of the effect of process parameters on casting quality and the necessary boundary conditions for computer modeling and simulation so as to minimize costly field trials. This dissertation attempts to address some of these concerns facing today's foundry industry. An experimental investigation of the Indirect Squeeze Casting Process was conducted by pouring molten Al-7Si-0.3Mg (A356) alloy into a specially designed and instrumented mold, mounted on a horizontal clamped-vertical shot squeeze caster (HVSC). Temperature measurements close to the metal/mold interface were made and compared with the results of the numerical simulation of heat flow during solidification and cooling of castings. The Heat Transfer Coefficient (HTC), a critical parameter essential for any solidification simulation, was estimated based on the simulation that gave the best fit to the experimental temperature data. During the solidification process, the HTC is relatively uniform over the entire casting and on reaching a critical solidification pressure, the HTC is close to 4500 W/m2 K. The work has also provided a correlation of Secondary Dendrite Arm Spacing (SDAS) with cooling rate for a modified A356 alloy. Low Pressure Permanent Mold Casting experiments were conducted by pouring a nearly identical aluminum alloy into an instrumented, coated mold mounted on a low pressure casting machine. The pressure levels, along with the time required to achieve complete filling, were microprocessor controlled in the casting machine. The HTC evaluation and SDAS-Cooling Rate Correlation were made in a similar manner to the Squeeze Casting study. A novel approach to estimating the HTC, accounting for the temporal and spatial temperature and thermal property variations, is presented. The maximum and minimum values of the HTC in this case were close to 2000 W/m2 K with no air gap and 400 W/m2 K with an air gap formation. The influences of air gap formation and mold coatings in controlling interfacial heat transfer were also modeled. It is expected that the HTCs and SDAS-Cooling Rate Correlations for the two casting processes will assist foundry engineers in deriving maximum benefits from each process.

  19. Predicting Pattern Tooling and Casting Dimensions for Investment Casting, Phase III

    SciTech Connect

    Sabau, Adrian S

    2008-04-01

    Efforts during Phase III focused mainly on the shell-alloy systems. A high melting point alloy, 17-4PH stainless steel, was considered. The experimental part of the program was conducted at ORNL and commercial foundries, where wax patterns were injected, molds were invested, and alloys were poured. Shell molds made of fused-silica and alumino-silicates were considered. A literature review was conducted on thermophysical and thermomechanical properties alumino-silicates. Material property data, which were not available from material suppliers, was obtained. For all the properties of 17-4PH stainless steel, the experimental data available in the literature did not cover the entire temperature range necessary for process simulation. Thus, some material properties were evaluated using ProCAST, based on CompuTherm database. A comparison between the predicted material property data and measured property data was made. It was found that most material properties were accurately predicted only over several temperature ranges. No experimental data for plastic modulus were found. Thus, several assumptions were made and ProCAST recommendations were followed in order to obtain a complete set of mechanical property data at high temperatures. Thermal expansion measurements for the 17-4PH alloy were conducted during heating and cooling. As a function of temperature, the thermal expansion for both the alloy and shell mold materials showed different evolution on heating and cooling. Numerical simulations were performed using ProCAST for the investment casting of 17-4PH stainless steel parts in fused silica molds using the thermal expansion obtained on heating and another one with thermal expansion obtained on cooling. Since the fused silica shells had the lowest thermal expansion properties in the industry, the dewaxing phase, including the coupling between wax-shell systems, was neglected. The shell mold was considered to be a pure elastic material. The alloy dimensions were obtained from numerical simulations. For 17-4PH stainless steel parts, the alloy shrinkage factors were over-predicted, as compared with experimental data. Additional R&D focus was placed on obtaining material property data for filled waxes, waxes that are common in the industry. For the first time in the investment casting industry, the thermo-mechanical properties of unfilled and filled waxes were measured. Test specimens of three waxes were injected at commercial foundries. Rheometry measurement of filled waxes was conducted at ORNL. The analysis of the rheometry data to obtain viscoelastic properties was not completed due to the reduction in the budget of the project (approximately 50% funds were received).

  20. The use of radiographs in small cast-gold restorations

    SciTech Connect

    Mattingly, S.L.; Podshadley, A.G.; Gullett, C.E.

    1982-07-01

    The rationale for the use of treatment radiographs in the construction of cast-gold restorations has been presented. Radiographs are made in the University of Louisville Fixed Prosthodontics Clinic at the precementation and postcementation stage of treatment when casting margins are inaccessible. Radiographs at this stage of treatment permit detection and correction of a variety of problems that may not be discovered clinically and allow the construction of excellent cast-gold restorations that would be impossible otherwise. Because all radiation safety factors are observed, the amount of radiation a patient receives is minimized.

  1. Hanford's Simulated Low Activity Waste Cast Stone Processing

    SciTech Connect

    Kim, Young

    2013-08-20

    Cast Stone is undergoing evaluation as the supplemental treatment technology for Hanford’s (Washington) high activity waste (HAW) and low activity waste (LAW). This report will only cover the LAW Cast Stone. The programs used for this simulated Cast Stone were gradient density change, compressive strength, and salt waste form phase identification. Gradient density changes show a favorable outcome by showing uniformity even though it was hypothesized differently. Compressive strength exceeded the minimum strength required by Hanford and greater compressive strength increase seen between the uses of different salt solution The salt waste form phase is still an ongoing process as this time and could not be concluded.

  2. Filler metal alloy for welding cast nickel aluminide alloys

    DOEpatents

    Santella, M.L.; Sikka, V.K.

    1998-03-10

    A filler metal alloy used as a filler for welding cast nickel aluminide alloys contains from about 15 to about 17 wt. % chromium, from about 4 to about 5 wt. % aluminum, equal to or less than about 1.5 wt. % molybdenum, from about 1 to about 4.5 wt. % zirconium, equal to or less than about 0.01 wt. % yttrium, equal to or less than about 0.01 wt. % boron and the balance nickel. The filler metal alloy is made by melting and casting techniques such as are melting the components of the filler metal alloy and cast in copper chill molds. 3 figs.

  3. Clinical experience with a water activated fiberglass casting material.

    PubMed

    Velazco, A; St Pierre, R; Fleming, L L

    1982-09-01

    One of several new types of synthetic casting material available in the market (Scotchcast) was evaluated. This system has the advantage of being a fiberglass tape activated by water. In a prospective study of 100 patients whose fractures were casted with this fiberglass tape, we found this system easy to use, light, strong, durable, and water resistant. Our patients developed few complications, most of which were attributable to our inexperience with the system. Cost, while greater than that for the typical plaster cast, was not prohibitive. PMID:24830622

  4. Corrosive wear of cast iron under reciprocating lubrication

    SciTech Connect

    Yahagi, Y.; Nagasawa, Y.; Hotta, S.; Mizutani, Y.

    1986-01-01

    In order to study the wear of cylinder bore fundamentally, a reciprocating friction tester was produced and utilized. The friction between a cast iron and a piston-ring and the wear of the cast iron were examined under the corrosive oil with sulphuric acid. The findings indicate that the friction and wear around TDC and BDC was confirmed to be greater than between these reversal points and the friction and wear around the reversal points increased with the sulphuric acid which has caused the deficiency of oil film and the corrosion of the cast iron.

  5. Design and Analysis for Melt Casting Metallic Fuel Pins

    SciTech Connect

    Wu, Xiaolong; Clarksean, Randy; Chen, Yitung; Meyer, Mitchell K.

    2002-07-01

    A concept for the casting of metallic fuels pins containing low vapor pressure materials is presented and discussed. The important physics of this concept include the mass transport of americium from the melt, the induction heating and stirring of the melt, plus the casting of long slender fuel rods. This paper discusses and presents preliminary modeling results for the casting of long, slender fuel rods. The model considers the flow of the melt into the molds, heat transfer into the molds, and the impact of process parameters on the formation of the fuel rod. (authors)

  6. Prosthetic management of malpositioned implant using custom cast abutment

    PubMed Central

    Chatterjee, Aishwarya; Ragher, Mallikarjuna; Patil, Sanket; Chatterjee, Debopriya; Dandekeri, Savita; Prabhu, Vishnu

    2015-01-01

    Two cases are reported with malpositioned implants. Both the implants were placed 6–7 months back. They had osseointegrated well with the surrounding bone. However, they presented severe facial inclination. Case I was restored with custom cast abutment with an auto polymerizing acrylic gingival veneer. Case II was restored with custom cast UCLA type plastic implant abutment. Ceramic was directly fired on the custom cast abutments. The dual treatment strategy resulted in functional and esthetic restorations despite facial malposition of the implants. PMID:26538957

  7. Freeze Tape Casting of Functionally Graded Porous Ceramics

    NASA Technical Reports Server (NTRS)

    Sofie, Stephen W.

    2007-01-01

    Freeze tape casting is a means of making preforms of ceramic sheets that, upon subsequent completion of fabrication processing, can have anisotropic and/or functionally graded properties that notably include aligned and graded porosity. Freeze tape casting was developed to enable optimization of the microstructures of porous ceramic components for use as solid oxide electrodes in fuel cells: Through alignment and grading of pores, one can tailor surface areas and diffusion channels for flows of gas and liquid species involved in fuel-cell reactions. Freeze tape casting offers similar benefits for fabrication of optimally porous ceramics for use as catalysts, gas sensors, and filters.

  8. Numerical Simulation of Cast Distortion in Gas Turbine Engine Components

    NASA Astrophysics Data System (ADS)

    Inozemtsev, A. A.; Dubrovskaya, A. S.; Dongauser, K. A.; Trufanov, N. A.

    2015-06-01

    In this paper the process of multiple airfoilvanes manufacturing through investment casting is considered. The mathematical model of the full contact problem is built to determine stress strain state in a cast during the process of solidification. Studies are carried out in viscoelastoplastic statement. Numerical simulation of the explored process is implemented with ProCASTsoftware package. The results of simulation are compared with the real production process. By means of computer analysis the optimization of technical process parameters is done in order to eliminate the defect of cast walls thickness variation.

  9. Residual stresses in a cast iron automotive brake disc rotor

    NASA Astrophysics Data System (ADS)

    Ripley, Maurice I.; Kirstein, Oliver

    2006-11-01

    Runout, and consequent juddering and pulsation through the brake pedal, is a multi-million dollar per year warranty problem for car manufacturers. There is some suspicion that the runout can be caused by relaxation of residual casting stresses when the disc is overheated during severe-braking episodes. We report here neutron-diffraction measurements of the levels and distribution of residual strains in a used cast iron brake disc rotor. The difficulties of measuring stresses in grey cast iron are outlined and three-dimensional residual-strain distributions are presented and their possible effects discussed.

  10. A combined experimental and modeling approach to uranium casting

    SciTech Connect

    Korzekwa, D.; Dunn, P.

    1994-08-01

    U casting was studied using a combined experimental and modeling approach; the U is cast into graphite molds using vacuum induction melting. Mold design and process parameters were varied. FLOW-3D and ABAQUS codes were used. Temperature predictions were compared with experimental data from thermcouples in the mold; initial metal and mold temperatures were used in input to FLOW-3D. Fluid flow predictions were validated using static and dynamic radiographic data. Dynamic radiographic videos of gold castings were compared to 3D simulations.

  11. Shrinkage Prediction for the Investment Casting of Stainless Steels

    SciTech Connect

    Sabau, Adrian S

    2007-01-01

    In this study, the alloy shrinkage factors were obtained for the investment casting of 17-4PH stainless steel parts. For the investment casting process, unfilled wax and fused silica with a zircon prime coat were used for patterns and shell molds, respectively. Dimensions of the die tooling, wax pattern, and casting were measured using a Coordinate Measurement Machine in order to obtain the actual tooling allowances. The alloy dimensions were obtained from numerical simulation results of solidification, heat transfer, and deformation phenomena. The numerical simulation results for the shrinkage factors were compared with experimental results.

  12. Fabricating an Accurate Implant Master Cast: A Technique Report.

    PubMed

    Balshi, Thomas J; Wolfinger, Glenn J; Alfano, Stephen G; Cacovean, Jeannine N; Balshi, Stephen F

    2015-12-01

    The technique for fabricating an accurate implant master cast following the 12-week healing period after Teeth in a Day® dental implant surgery is detailed. The clinical, functional, and esthetic details captured during the final master impression are vital to creating an accurate master cast. This technique uses the properties of the all-acrylic resin interim prosthesis to capture these details. This impression captures the relationship between the remodeled soft tissue and the interim prosthesis. This provides the laboratory technician with an accurate orientation of the implant replicas in the master cast with which a passive fitting restoration can be fabricated. PMID:26215098

  13. Method to prevent/mitigate steam explosions in casting pits

    DOEpatents

    Taleyarkhan, Rusi P. (Knoxville, TN)

    1996-01-01

    Steam explosions can be prevented or mitigated during a metal casting process by the placement of a perforated flooring system in the casting pit. An upward flow of compressed gas through this perforated flooring system is introduced during the casting process to produce a buffer layer between any spilled molten metal and the cooling water in the reservoir. This buffer layer provides a hydrodynamic layer which acts to prevent or mitigate steam explosions resulting from hot, molten metal being spilled into or onto the cooling water.

  14. Method to prevent/mitigate steam explosions in casting pits

    DOEpatents

    Taleyarkhan, R.P.

    1996-12-24

    Steam explosions can be prevented or mitigated during a metal casting process by the placement of a perforated flooring system in the casting pit. An upward flow of compressed gas through this perforated flooring system is introduced during the casting process to produce a buffer layer between any spilled molten metal and the cooling water in the reservoir. This buffer layer provides a hydrodynamic layer which acts to prevent or mitigate steam explosions resulting from hot, molten metal being spilled into or onto the cooling water. 3 figs.

  15. An accelerated clinical chairside technique for casting overdenture attachment copings.

    PubMed

    Scherer, Michael D; Campagni, Wayne V

    2011-11-01

    An accelerated technique for casting a direct-pattern post and core restoration for use in fixed prosthodontics has been previously described. Similar techniques for use in removable prosthodontics show potential for clinical use, specifically for the fabrication of radicular stud overdenture attachments and their corresponding copings. The procedure uses a chairside technique and readily available components to fabricate a direct, acrylic resin pattern combining the elements of a cast coping with a fixed radicular attachment. This pattern can subsequently be invested, cast, finished and polished, luted, and attached to the removable prosthesis in a single clinical appointment. PMID:22024184

  16. Optimization of Squeeze Casting for Aluminum Alloy Parts

    SciTech Connect

    David Schwam; John F. Wallace; Qingming Chang; Yulong Zhu

    2002-07-30

    This study was initiated with the installation of a new production size UBE 350 Ton VSC Squeeze Casting system in the Metal Casting Laboratory at Case Western University. A Lindberg 75k W electrical melting furnace was installed alongside. The challenge of installation and operation of such industrial-size equipment in an academic environment was met successfully. Subsequently, a Sterling oil die heater and a Visi-Track shot monitoring system were added. A significant number of inserts were designed and fabricated over the span of the project, primarily for squeeze casting different configurations of test bars and plates. A spiral ''ribbon insert'' for evaluation of molten metal fluidity was also fabricated. These inserts were used to generate a broad range of processing conditions and determine their effect on the quality of the squeeze cast parts. This investigation has studied the influence of the various casting variables on the quality of indirect squeeze castings primarily of aluminum alloys. The variables studied include gating design, fill time and fill patter, metal pressure and die temperature variations. The quality of the die casting was assessed by an analysis of both their surface condition and internal soundness. The primary metal tested was an aluminum 356 alloy. In addition to determining the effect of these casting variables on casting quality as measured by a flat plate die of various thickness, a number of test bar inserts with different gating designs have been inserted in the squeeze casting machine. The mechanical properties of these test bars produced under different squeeze casting conditions were measured and reported. The investigation of the resulting properties also included an analysis of the microstructure of the squeeze castings and the effect of the various structural constituents on the resulting properties. The main conclusions from this investigation are as follows: The ingate size and shape are very important since it must remain open until the casting is solidified and pressure is maintained on the solidifying casting. Fanned gates, particularly on the smaller section castings avoid jetting effects at the ingate end. The fan type ingate helps accomplish a rapid fill without high velocities. The molten metal has to fill the cavity before localized solidification occurs. This is best accomplished with a larger ingate to attain rapid filling without excessive velocity or jetting that occurs at high metal velocities. Straight gates are prone to case jetting of the metal stream even a low velocities. Fanned gates allow use of higher fill velocity without excessive jetting. A higher metal pressure provides a more complete fill of the die including improved compensation for solidification shrinkage. With the proper filling pattern, ingates, overflows and die temperature for a given die, very good tensile properties can be attained in squeeze casting. In general, the smaller squeeze castings require higher die temperatures. Computer models using the UES Procast and MagmaSoft finite element software can, after suitable adjustments, predict the flow pattern in the die cavity.

  17. Influence of Melt Feeding Scheme and Casting Parameters During Direct-Chill Casting on Microstructure of an AA7050 Billet

    NASA Astrophysics Data System (ADS)

    Zhang, L.; Eskin, D. G.; Miroux, A.; Subroto, T.; Katgerman, L.

    2012-12-01

    Direct-chill (DC) casting billets of an AA7050 alloy produced with different melt feeding schemes and casting speeds were examined in order to reveal the effect of these factors on the evolution of microstructure. Experimental results show that grain size is strongly influenced by the casting speed. In addition, the distribution of grain sizes across the billet diameter is mostly determined by melt feeding scheme. Grains tend to coarsen towards the center of a billet cast with the semi-horizontal melt feeding, while upon vertical melt feeding the minimum grain size was observed in the center of the billet. Computer simulations were preformed to reveal sump profiles and flow patterns during casting under different melt feeding schemes and casting speeds. The results show that solidification front and velocity distribution of the melt in the liquid and slurry zones are very different under different melt feeding scheme. The final grain structure and the grain size distribution in a DC casting billet is a result of a combination of fragmentation effects in the slurry zone and the cooling rate in the solidification range.

  18. Advanced lost foam casting quarterly report, October 1, 1995--December 31, 1995

    SciTech Connect

    1995-12-31

    Objective is to advance the state of the art in lost foam casting technology, in order to improve the competitiveness of the US metals casting industries. The following tasks are reported on pyrolysis defects and sand distortion, bronze casting technology, steel casting technology, sand filling and compaction, coating technology, precision pattern production, and computational modeling.

  19. 49 CFR 192.373 - Service lines: Cast iron and ductile iron.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Service lines: Cast iron and ductile iron. 192.373... Regulators, and Service Lines 192.373 Service lines: Cast iron and ductile iron. (a) Cast or ductile iron... cast iron pipe or ductile iron pipe is installed for use as a service line, the part of the...

  20. 49 CFR 192.373 - Service lines: Cast iron and ductile iron.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Service lines: Cast iron and ductile iron. 192.373... Regulators, and Service Lines 192.373 Service lines: Cast iron and ductile iron. (a) Cast or ductile iron... cast iron pipe or ductile iron pipe is installed for use as a service line, the part of the...

  1. 49 CFR 192.373 - Service lines: Cast iron and ductile iron.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Service lines: Cast iron and ductile iron. 192.373... Regulators, and Service Lines 192.373 Service lines: Cast iron and ductile iron. (a) Cast or ductile iron... cast iron pipe or ductile iron pipe is installed for use as a service line, the part of the...

  2. 40 CFR 464.30 - Applicability; description of the ferrous casting subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... ferrous casting subcategory. 464.30 Section 464.30 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) METAL MOLDING AND CASTING POINT SOURCE CATEGORY Ferrous Casting Subcategory 464.30 Applicability; description of the ferrous casting...

  3. 40 CFR 464.30 - Applicability; description of the ferrous casting subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... ferrous casting subcategory. 464.30 Section 464.30 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS METAL MOLDING AND CASTING POINT SOURCE CATEGORY Ferrous Casting Subcategory 464.30 Applicability; description of the ferrous casting subcategory....

  4. 40 CFR 464.30 - Applicability; description of the ferrous casting subcategory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... ferrous casting subcategory. 464.30 Section 464.30 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) METAL MOLDING AND CASTING POINT SOURCE CATEGORY Ferrous Casting Subcategory 464.30 Applicability; description of the ferrous casting...

  5. 40 CFR 466.20 - Applicability; description of the cast iron basis material subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 30 2014-07-01 2014-07-01 false Applicability; description of the cast... CATEGORY Cast Iron Basis Material Subcategory 466.20 Applicability; description of the cast iron basis... of pollutants into publicly owned treatment works from porcelain enameling of cast iron...

  6. 40 CFR 466.20 - Applicability; description of the cast iron basis material subcategory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 31 2013-07-01 2013-07-01 false Applicability; description of the cast... CATEGORY Cast Iron Basis Material Subcategory 466.20 Applicability; description of the cast iron basis... of pollutants into publicly owned treatment works from porcelain enameling of cast iron...

  7. 40 CFR 466.20 - Applicability; description of the cast iron basis material subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 31 2012-07-01 2012-07-01 false Applicability; description of the cast... CATEGORY Cast Iron Basis Material Subcategory 466.20 Applicability; description of the cast iron basis... of pollutants into publicly owned treatment works from porcelain enameling of cast iron...

  8. 40 CFR 464.30 - Applicability; description of the ferrous casting subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... ferrous casting subcategory. 464.30 Section 464.30 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS METAL MOLDING AND CASTING POINT SOURCE CATEGORY Ferrous Casting Subcategory 464.30 Applicability; description of the ferrous casting subcategory....

  9. 40 CFR 464.30 - Applicability; description of the ferrous casting subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... ferrous casting subcategory. 464.30 Section 464.30 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) METAL MOLDING AND CASTING POINT SOURCE CATEGORY Ferrous Casting Subcategory 464.30 Applicability; description of the ferrous casting...

  10. Clean ferrous casting technology research. Final technical report, September 29, 1993--December 31, 1995

    SciTech Connect

    Piwonka, T.S.

    1996-01-01

    This report details results of a 30-month program to develop methods of making clean ferrous castings, i.e., castings free of inclusions and surface defects. The program was divided into 3 tasks: techniques for producing clean steel castings, electromagnetic removal of inclusions from ferrous melts, and study of causes of metal penetration in sand molds in cast iron.

  11. 40 CFR 464.20 - Applicability; description of the copper casting subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... copper casting subcategory. 464.20 Section 464.20 Protection of Environment ENVIRONMENTAL PROTECTION... Copper Casting Subcategory § 464.20 Applicability; description of the copper casting subcategory. The... introduction of pollutants into publicly owned treatment works resulting from copper casting operations...

  12. 40 CFR 464.20 - Applicability; description of the copper casting subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... copper casting subcategory. 464.20 Section 464.20 Protection of Environment ENVIRONMENTAL PROTECTION... CATEGORY Copper Casting Subcategory § 464.20 Applicability; description of the copper casting subcategory... introduction of pollutants into publicly owned treatment works resulting from copper casting operations...

  13. 40 CFR 464.20 - Applicability; description of the copper casting subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... copper casting subcategory. 464.20 Section 464.20 Protection of Environment ENVIRONMENTAL PROTECTION... CATEGORY Copper Casting Subcategory § 464.20 Applicability; description of the copper casting subcategory... introduction of pollutants into publicly owned treatment works resulting from copper casting operations...

  14. 40 CFR 464.20 - Applicability; description of the copper casting subcategory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... copper casting subcategory. 464.20 Section 464.20 Protection of Environment ENVIRONMENTAL PROTECTION... CATEGORY Copper Casting Subcategory § 464.20 Applicability; description of the copper casting subcategory... introduction of pollutants into publicly owned treatment works resulting from copper casting operations...

  15. 40 CFR 464.20 - Applicability; description of the copper casting subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... copper casting subcategory. 464.20 Section 464.20 Protection of Environment ENVIRONMENTAL PROTECTION... Copper Casting Subcategory § 464.20 Applicability; description of the copper casting subcategory. The... introduction of pollutants into publicly owned treatment works resulting from copper casting operations...

  16. 40 CFR 464.10 - Applicability; description of the aluminum casting subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... aluminum casting subcategory. 464.10 Section 464.10 Protection of Environment ENVIRONMENTAL PROTECTION... Aluminum Casting Subcategory § 464.10 Applicability; description of the aluminum casting subcategory. The... introduction of pollutants into publicly owned treatment works resulting from aluminum casting operations...

  17. 40 CFR 464.10 - Applicability; description of the aluminum casting subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... aluminum casting subcategory. 464.10 Section 464.10 Protection of Environment ENVIRONMENTAL PROTECTION... Aluminum Casting Subcategory § 464.10 Applicability; description of the aluminum casting subcategory. The... introduction of pollutants into publicly owned treatment works resulting from aluminum casting operations...

  18. 49 CFR 192.373 - Service lines: Cast iron and ductile iron.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... line which extends through the building wall must be of steel pipe. (c) A cast iron or ductile iron... 49 Transportation 3 2011-10-01 2011-10-01 false Service lines: Cast iron and ductile iron. 192.373... Regulators, and Service Lines 192.373 Service lines: Cast iron and ductile iron. (a) Cast or ductile...

  19. Caste, Class and the Love-Marriage: Social Change in India

    ERIC Educational Resources Information Center

    Corwin, Lauren A.

    1977-01-01

    The present study of a small town in rural West Bengal, India, reveals a number of "love-marriages" involving individuals from castes of distinctly different ranks in the local caste hierarchy. Despite the prevailing rule of caste endogamy, inter-caste couples appear to face little difficulty. (Author)

  20. 49 CFR 192.373 - Service lines: Cast iron and ductile iron.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Service lines: Cast iron and ductile iron. 192.373... Regulators, and Service Lines 192.373 Service lines: Cast iron and ductile iron. (a) Cast or ductile iron... cast iron pipe or ductile iron pipe is installed for use as a service line, the part of the...

  1. 46 CFR 59.20-1 - Carbon-steel or alloy-steel castings.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 2 2014-10-01 2014-10-01 false Carbon-steel or alloy-steel castings. 59.20-1 Section 59... BOILERS, PRESSURE VESSELS AND APPURTENANCES Welding Repairs to Castings § 59.20-1 Carbon-steel or alloy-steel castings. Defects in carbon-steel or alloy-steel castings may be repaired by welding. The...

  2. 46 CFR 59.20-1 - Carbon-steel or alloy-steel castings.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 2 2011-10-01 2011-10-01 false Carbon-steel or alloy-steel castings. 59.20-1 Section 59... BOILERS, PRESSURE VESSELS AND APPURTENANCES Welding Repairs to Castings § 59.20-1 Carbon-steel or alloy-steel castings. Defects in carbon-steel or alloy-steel castings may be repaired by welding. The...

  3. 46 CFR 59.20-1 - Carbon-steel or alloy-steel castings.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Carbon-steel or alloy-steel castings. 59.20-1 Section 59... BOILERS, PRESSURE VESSELS AND APPURTENANCES Welding Repairs to Castings § 59.20-1 Carbon-steel or alloy-steel castings. Defects in carbon-steel or alloy-steel castings may be repaired by welding. The...

  4. 46 CFR 59.20-1 - Carbon-steel or alloy-steel castings.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 2 2012-10-01 2012-10-01 false Carbon-steel or alloy-steel castings. 59.20-1 Section 59... BOILERS, PRESSURE VESSELS AND APPURTENANCES Welding Repairs to Castings § 59.20-1 Carbon-steel or alloy-steel castings. Defects in carbon-steel or alloy-steel castings may be repaired by welding. The...

  5. 46 CFR 59.20-1 - Carbon-steel or alloy-steel castings.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 2 2013-10-01 2013-10-01 false Carbon-steel or alloy-steel castings. 59.20-1 Section 59... BOILERS, PRESSURE VESSELS AND APPURTENANCES Welding Repairs to Castings § 59.20-1 Carbon-steel or alloy-steel castings. Defects in carbon-steel or alloy-steel castings may be repaired by welding. The...

  6. Study of FES/CAST/HGS

    NASA Technical Reports Server (NTRS)

    Workman, Gary L.; Cummings, Rick; Jones, Brian

    1992-01-01

    The microgravity materials processing program has been instrumental in providing the crystal growth community with an experimental environment to better understand the phenomena associated with the growing of crystals. In many applications one may pursue the growth of large single crystals which cannot be grown on earth due to convective driven flows. A microgravity environment is characterized by neither convection of buoyancy. Consequently superior crystals are able to be grown in space. On the other hand, since neither convection nor buoyancy dominates the fluid flow in a microgravity environment, then lesser dominating phenomena can affect crystal growth, such as surface driven flows or diffusion limited solidification. In the case of experiments that are to be flown in space using the Fluid Experiments System (FES), diffusion limited growth should be the dominating phenomenon. The use of holographic and Schlieren optical techniques for studying the concentration gradients in solidification processes has been used by several investigators over the years. The Holographic Ground System (HGS) facility at MSFC has been a primary resource in researching this capability. Consequently scientific personnel have been able to utilize these techniques in both ground based research and in space experiments. An important event in the scientific utilization of the HGS facilities was the TGS (triglycine sulfate) Crystal Growth and the Casting and Solidification Technology (CAST) experiments that were flown on the International Microgravity Lab (IML) mission in March of this year. The preparation and processing of these space observations are the primary experiments reported in this work. This project provides some ground-based studies to optimize on the holographic techniques used to acquire information about the crystal growth processes flown on IML. Since the ground-based studies will be compared with the space-based experimental results, it is necessary to conduct sufficient ground based studies to best determine how the experiment in space worked. The current capabilities in computer based systems for image processing and numerical computation have certainly assisted in those efforts. As anticipated, this study has certainly shown that these advanced computing capabilities are helpful in the data analysis of such experiments.

  7. Method of casting articles of a bulk-solidifying amorphous alloy

    DOEpatents

    Lin, Xianghong (Laguna Niguel, CA); Johnson, William L. (Pasadena, CA); Peker, Atakan (Aliso Viejo, CA)

    1998-01-01

    A casting charge of a bulk-solidifying amorphous alloy is cast into a mold from a temperature greater than its crystallized melting temperature, and permitted to solidify to form an article. The oxygen content of the casting charge is limited to an operable level, as excessively high oxygen contents produce premature crystallization during the casting operation. During melting, the casting charge is preferably heated to a temperature above a threshold temperature to eliminate heterogeneous crystallization nucleation sites within the casting charge. The casting charge may be cast from above the threshold temperature, or it may be cooled to the casting temperature of more than the crystallized melting point but not more than the threshold temperature, optionally held at this temperature for a period of time, and thereafter cast.

  8. Distal radius fractures: a prospective randomized comparison of fibreglass tape with QuickCast.

    PubMed

    Cohen, M S; Frillman, T

    1997-05-01

    Cast immobilization remains the most commonly employed method in the treatment of distal radius fractures. In an effort to test a new shrinkable polymer-coated casting material (QuickCast), a prospective randomized study was performed on 30 consecutive distal radius fractures. Fractures were divided into three groups based on the severity of fracture and treated with either a conventional short-arm fibreglass tape cast or a QuickCast. Results showed no significant differences in minor cast complications or maintenance of fracture reduction between conventional fibreglass tape and the QuickCast material. The shrinkable QuickCast, however, resulted in an average of one less cast change in all groups. This reduction in time and labour must be weighed against the slightly increased cost of the QuickCast immobilizer. PMID:9282188

  9. Method of casting articles of a bulk-solidifying amorphous alloy

    DOEpatents

    Lin, X.; Johnson, W.L.; Peker, A.

    1998-08-25

    A casting charge of a bulk-solidifying amorphous alloy is cast into a mold from a temperature greater than its crystallized melting temperature, and permitted to solidify to form an article. The oxygen content of the casting charge is limited to an operable level, as excessively high oxygen contents produce premature crystallization during the casting operation. During melting, the casting charge is preferably heated to a temperature above a threshold temperature to eliminate heterogeneous crystallization nucleation sites within the casting charge. The casting charge may be cast from above the threshold temperature, or it may be cooled to the casting temperature of more than the crystallized melting point but not more than the threshold temperature, optionally held at this temperature for a period of time, and thereafter cast. 8 figs.

  10. INTERIOR VIEW LOOKING WEST, CAST HOUSE OF BLAST FURNACE NO. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR VIEW LOOKING WEST, CAST HOUSE OF BLAST FURNACE NO. 1 AND BLAST FURNACE NO. 2. - Pittsburgh Steel Company, Monessen Works, Blast Furnace No. 1 & No. 2, Donner Avenue, Monessen, Westmoreland County, PA

  11. 13. SOUTHWEST VIEW OF CAST HOUSE No. 1, BLAST FURNACE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    13. SOUTHWEST VIEW OF CAST HOUSE No. 1, BLAST FURNACE No. 1, AND HOIST HOUSE No. 1. (Martin Stupich) - U.S. Steel Duquesne Works, Blast Furnace Plant, Along Monongahela River, Duquesne, Allegheny County, PA

  12. 67. INTERIOR VIEW OF THE CAST HOUSE OR DOROTHY SIX ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    67. INTERIOR VIEW OF THE CAST HOUSE OR DOROTHY SIX BLAST FURNACE LOOKING NORTHEAST. (Jet Lowe) - U.S. Steel Duquesne Works, Blast Furnace Plant, Along Monongahela River, Duquesne, Allegheny County, PA

  13. 56. LOOKING NORTH AT DOROTHY SIX BLAST FURNACE WITH CAST ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    56. LOOKING NORTH AT DOROTHY SIX BLAST FURNACE WITH CAST HOUSE IN FOREGROUND AND DUSTCATCHER AT RIGHT OF FURNACE (Jet Lowe) - U.S. Steel Duquesne Works, Blast Furnace Plant, Along Monongahela River, Duquesne, Allegheny County, PA

  14. Adhesive Wear Behavior of Heat Treated Spheroidal Graphite Cast Iron

    NASA Astrophysics Data System (ADS)

    Salim, M.; Shama, S.; Mozumder, Y. H.; Behera, R. K.; P, Sindhoora L.; Pattanaik, A.; Mishra, S. C.; Sen, S.

    2015-02-01

    Spheroidal graphite cast iron is one of the most favorable materials in cast iron family due to its wide range of mechanical and tribological properties. In the current research priority is given towards the investigation of wear system response of spheroidal graphite cast iron subjected to various heat treatment conditions. Pearlitic/ferritic and upper bainitic matrix was obtained through normalizing and austempering treatment for an austenitizing temperature of 1000C. Dry sliding wear test was performed at 10N, 20N, 30N for a sliding distance of 7.54m. With increase in load weight loss was observed for as-cast specimen whereas normalized specimen showed very less weight loss with increasing load. On the other hand the austempered specimen observed to lose weight when operated at 10N, whereas at 20N and 30N drastic gain in weight was observed.

  15. Development Program for Natural Aging Aluminum Casting Alloys

    SciTech Connect

    Dr. Geoffrey K. Sigworth

    2004-05-14

    A number of 7xx aluminum casting alloys are based on the ternary Al-Zn-Mg system. These alloys age naturally to high strength at room temperature. A high temperature solution and aging treatment is not required. Consequently, these alloys have the potential to deliver properties nearly equivalent to conventional A356-T6 (Al-Si-Mg) castings, with a significant cost saving. An energy savings is also possible. In spite of these advantages, the 7xx casting alloys are seldom used, primarily because of their reputation for poor castibility. This paper describes the results obtained in a DOE-funded research study of these alloys, which is part of the DOE-OIT ''Cast Metals Industries of the Future'' Program. Suggestions for possible commercial use are also given.

  16. The lost-foam casting of aluminum alloy components

    NASA Astrophysics Data System (ADS)

    Shivkumar, S.; Wang, L.; Apelian, D.

    1990-11-01

    In the lost-foam casting process, liquid metal is poured directly onto a refractory-coated, foamed polymer pattern which is buried in loose sand. The polymer pattern undergoes thermal degradation and is gradually replaced by the molten metal, which solidifies and produces the casting. The inherent operating advantages of this innovative technique have generated considerable interest among casting manufacturers. Currently, the process is being utilized to manufacture a wide variety of ferrous and nonferrous components catering primarily to the automotive industry. Because the process is relatively new, there is a compelling need to quantify the influence of process parameters on microstructure and mechanical properties. Furthermore, the interaction of the thermal degradation products with the solidifying metal may produce several unique defects in the casting.

  17. 35. CARRIE FURNACE No. 6 AND CAST HOUSE. THE CARRIE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    35. CARRIE FURNACE No. 6 AND CAST HOUSE. THE CARRIE BOILER SHOP IS ON THE RIGHT, IN FRONT OF HOT BLAST STOVES. - U.S. Steel Homestead Works, Blast Furnace Plant, Along Monongahela River, Homestead, Allegheny County, PA

  18. Residual stress in spin-cast polyurethane thin films

    SciTech Connect

    Zhang, Hong; Zhang, Li

    2015-01-19

    Residual stress is inevitable during spin-casting. Herein, we report a straightforward method to evaluate the residual stress in as-cast polyurethane thin films using area shrinkage measurement of films in floating state, which shows that the residual stress is independent of radial location on the substrate and decreased with decreasing film thickness below a critical value. We demonstrate that the residual stress is developed due to the solvent evaporation after vitrification during spin-casting and the polymer chains in thin films may undergo vitrification at an increased concentration. The buildup of residual stress in spin-cast polymer films provides an insight into the size effects on the nature of polymer thin films.

  19. 41. Casting floor, "B" furnace, pour in progress; mudgun is ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    41. Casting floor, "B" furnace, pour in progress; mudgun is to right of furnace; photo taken from furnace operator's booth. Looking south/southwest - Rouge Steel Company, 3001 Miller Road, Dearborn, Wayne County, MI

  20. 25. Detail of cast iron lamp post base with fluted ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    25. Detail of cast iron lamp post base with fluted wooded post at top, located at north end of bridge. VIEW NORTHEAST - Chelsea Street Bridge & Draw Tender's House, Spanning Chelsea River, Boston, Suffolk County, MA

  1. 3. FOURTH FLOOR OF OIL HOUSE (NOTICE CAST IRON SUPPORT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. FOURTH FLOOR OF OIL HOUSE (NOTICE CAST IRON SUPPORT POSTS AND OIL PRESS IN THE CENTER) - Wilson's Oil House, Lard Refinery, & Edible Fats Factory, Oil House, 2801 Southwest Fifteenth Street, Oklahoma City, Oklahoma County, OK

  2. Awareness programs and change in taste-based caste prejudice.

    PubMed

    Banerjee, Ritwik; Datta Gupta, Nabanita

    2015-01-01

    Becker's theory of taste-based discrimination predicts that relative employment of the discriminated social group will improve if there is a decrease in the level of prejudice for the marginally discriminating employer. In this paper we experimentally test this prediction offered by Garry Becker in his seminal work on taste based discrimination, in the context of caste in India, with management students (potential employers in the near future) as subjects. First, we measure caste prejudice and show that awareness through a TV social program reduces implicit prejudice against the lower caste and the reduction is sustained over time. Second, we find that the treatment reduces the prejudice levels of those in the left tail of the prejudice distribution--the group which can potentially affect real outcomes as predicted by the theory. And finally, a larger share of the treatment group subjects exhibit favorable opinion about reservation in jobs for the lower caste. PMID:25902290

  3. Advanced lost foam casting technology. 1995 summary report

    SciTech Connect

    Bates, C.E.; Littleton, H.E.; Askeland, D.; Griffin, J.; Miller, B.A.; Sheldon, D.S.

    1996-05-01

    Previous research made significant advances in understanding the Lost Foam Casting (LFC) Process and clearly identified areas where additional research was needed to improve the process and make it more functional in an industrial environment. The current project focused on five areas listed as follows: Task 1: Precision Pattern Production; Task 2: Pattern Coating Consistency; Task 3: Sand Fill and Compaction Effects; Task 4: Pattern Gating; and Task 5: Mechanical Properties of Castings. This report summarizes the work done under the current contract in all five areas. Twenty-eight (28) companies jointly participate in the project. These companies represent a variety of disciplines, including pattern designers, pattern producers, coating manufacturers, plant design companies, compaction equipment manufacturers, casting producers, and casting buyers. This report summarizes the work done in the past two years and the conclusions drawn from the work.

  4. An Energy Savings Model for the Heat Treatment of Castings

    SciTech Connect

    Y. Rong; R. Sisson; J. Morral; H. Brody

    2006-12-31

    An integrated system of software, databases, and design rules have been developed, verified, and to be marketed to enable quantitative prediction and optimization of the heat treatment of aluminum castings to increase quality, increase productivity, reduce heat treatment cycle times and reduce energy consumption. The software predicts the thermal cycle in critical locations of individual components in a furnace, the evolution of microstructure, and the attainment of properties in heat treatable aluminum alloy castings. The model takes into account the prior casting process and the specific composition of the component. The heat treatment simulation modules can be used in conjunction with software packages for simulation of the casting process. The system is built upon a quantitative understanding of the kinetics of microstructure evolution in complex multicomponent alloys, on a quantitative understanding of the interdependence of microstructure and properties, on validated kinetic and thermodynamic databases, and validated quantitative models.

  5. Synthetic casting tape as a facial impression tray material.

    PubMed

    Saunders, T R; Hansen, N A

    1995-08-01

    A procedure is described that uses thermoplastic synthetic casting tape for fabrication of facial impression trays. Once used, these trays can be disinfected without degradation of the tray material, which allows for storage and later use. PMID:8537924

  6. Use of casting tape for support of an extraoral impression.

    PubMed

    Siadat, Hakimeh; Mirfazaelian, Ali

    2003-12-01

    This article describes a technique for using casting tape to support irreversible hydrocolloid material when making extraoral impressions to increase patient comfort, save time, and produce less tissue distortion. PMID:14668762

  7. Effect of investment on casting high-fusing alloys.

    PubMed

    Barreto, M T; Goldberg, A J; Nitkin, D A; Mumford, G

    1980-11-01

    A definite interaction in castability was found between the three different phosphate-bonded investments and four different alloys tested in this study. 1. Casting completeness of all alloys, as measured by the length of test specimens, was affected by the investment. The high-gold content alloy, SMG II, yielded the most complete castings of all combinations teted when invested with Ceramigold. Of the nonprecious alloys, Biobond CB combined with Ceramigold II resulted in the longest samples. 2. The surface quality of Jelbon and SMG II castings was good, regardless of the investment used. Wiron S and Biobond CB varied in surface quality with different investments, Ceramigold II giving the smoothest castings. 3. All alloys, especially the nonprecious ones, should be tested for compatability with different investments before asserting their qualities or lack of qualities for clinical use. PMID:7003107

  8. 56. DETAIL OF BASE OF STEEL WINDMILL TOWER WITH CAST ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    56. DETAIL OF BASE OF STEEL WINDMILL TOWER WITH CAST IRON HAND PUMP OVER WELL HEAD ON HIGHWAY L44 IN IOWA JUST EAST OF NEBRASKA CITY, NEBRASKA. - Kregel Windmill Company Factory, 1416 Central Avenue, Nebraska City, Otoe County, NE

  9. BRASS FOUNDRY MACHINE ROOM USED TO MACHINE CAST BRONZE PIECES ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    BRASS FOUNDRY MACHINE ROOM USED TO MACHINE CAST BRONZE PIECES FOR VALVES AND PREPARE BRONZE VALVE BODIES FOR ASSEMBLY. - Stockham Pipe & Fittings Company, Brass Foundry, 4000 Tenth Avenue North, Birmingham, Jefferson County, AL

  10. Awareness Programs and Change in Taste-Based Caste Prejudice

    PubMed Central

    Banerjee, Ritwik; Datta Gupta, Nabanita

    2015-01-01

    Becker's theory of taste-based discrimination predicts that relative employment of the discriminated social group will improve if there is a decrease in the level of prejudice for the marginally discriminating employer. In this paper we experimentally test this prediction offered by Garry Becker in his seminal work on taste based discrimination, in the context of caste in India, with management students (potential employers in the near future) as subjects. First, we measure caste prejudice and show that awareness through a TV social program reduces implicit prejudice against the lower caste and the reduction is sustained over time. Second, we find that the treatment reduces the prejudice levels of those in the left tail of the prejudice distribution - the group which can potentially affect real outcomes as predicted by the theory. And finally, a larger share of the treatment group subjects exhibit favorable opinion about reservation in jobs for the lower caste. PMID:25902290

  11. 18. LOWER LATERAL SUPPORT DETAIL, HAND RAIL DETAILS, CAST STEEL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    18. LOWER LATERAL SUPPORT DETAIL, HAND RAIL DETAILS, CAST STEEL SHOE CONNECTIONS, AND HALF SECTIONS OF CONCRETE APPROACH SPANS - Jensen Bridge, Spanning Green River at Town of Jensen, Jensen, Uintah County, UT

  12. 42. Casting floor, "B" furnace, pour in progress; mudgun is ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    42. Casting floor, "B" furnace, pour in progress; mudgun is to right of furnace; operator takes temperature of iron in trough during pout. Looking south - Rouge Steel Company, 3001 Miller Road, Dearborn, Wayne County, MI

  13. 22 CFR 121.10 - Forgings, castings and machined bodies.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... components, accessories, attachments and parts as defined in 121.8), then the particular forging, casting, extrusion, machined body, etc., is considered a defense article subject to the controls of this...

  14. 22 CFR 121.10 - Forgings, castings and machined bodies.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... components, accessories, attachments and parts as defined in 121.8), then the particular forging, casting, extrusion, machined body, etc., is considered a defense article subject to the controls of this...

  15. Adjustable hinge permits movement of knee in plaster cast

    NASA Technical Reports Server (NTRS)

    Maley, W. E.

    1967-01-01

    Metal knee hinge with an adjustable sleeve worn on the outside of a leg cast facilitates movement of the knee joint. This helps eliminate stiffness of the knee and eliminates bulkiness and adjustment difficulty.

  16. Assessment of thermal embrittlement of cast stainless steels

    SciTech Connect

    Chopra, O.K.; Shack, W.J.

    1994-05-01

    A procedure and correlations are presented for assessing thermal embrittlement and predicting Charpy-impact energy and fracture toughness J-R curve of cast stainless steel components under Light Water Reactor operating conditions from known material information. The ``saturation`` impact strength and fracture toughness of a specific cast stainless steel, i.e., the minimum value that would be achieved for the material after long-term service, is estimated from the chemical composition of the steel. Fracture properties as a function of time and temperature of reactor service are estimated from the kinetics of embrittlement, which are also determined from chemical composition. A common ``predicted lower-bound`` J-R curve for cast stainless steels of unknown chemical composition is also defined for a given grade of steel, ferrite content, and temperature. Examples of estimating fracture toughness of cast stainless steel components during reactor service are presented.

  17. The nucleation of austenite in ferritic ductile cast iron

    SciTech Connect

    Chou, J.M.; Hon, M.H. ); Lee, J.L. )

    1992-07-01

    Austempered ductile cast iron has recently been receiving increasing attention because of its excellent combination of strength and ductility. Since the austenitization process has a significant influence on the mechanical properties of austempered ductile cast iron, several investigations on the nucleation sites of austenite and diffusion paths of carbon from spheroidal graphite have been reported in ferritic ductile cast iron. However, agreement on this subject has not ben reached. The purpose of this paper is to study the preferential nucleation sites of austenite during austenitization at two austenitizing temperatures in ferritic ductile cast iron. An attempt was made to understand the reasons which give rise to preferential austenite nucleation sites. The carbon diffusion paths from spheroidal graphite were also investigated.

  18. Casting Simulation of an Austrian Bronze Age Sword Hilt

    NASA Astrophysics Data System (ADS)

    Pola, Annalisa; Mödlinger, Marianne; Piccardo, Paolo; Montesano, Lorenzo

    2015-07-01

    Bronze Age swords with a metal hilt can be considered the peak of Bronze Age casting technologies. To reconstruct the casting techniques used more than 3000 years ago, a metal hilted sword of the Schalenknauf type from Lower Austria was studied with the aid of macroscopic analyses and simulation of mold filling and casting solidification. A three-dimensional model of the hilt was created based on optical scanner measurements performed on a hilt recently discovered during archaeological excavations. Three different configurations of the gating system were considered, two on the pommel disk and one on the knob, and the effect of its location on the formation of casting defects was investigated. Three-dimensional computed tomography was used to detect internal defects, such as gas and shrinkage porosity, which were then compared with those calculated by simulation. The best match between actual and predicted hilt quality demonstrated the location of the gating system, which turned out to be on the pommel disk.

  19. Nuclear-waste encapsulation by metal-matrix casting

    SciTech Connect

    Nelson, R.G.; Nesbitt, J.F.; Slate, S.C.

    1981-05-01

    Several encapsulation casting processes are described that were developed or used at the Pacific Northwest Laboratory to embed simulated high-level wastes of two different forms (glass marbles and ceramic pellets) in metal matrices. Preliminary evaluations of these casting processes and the products are presented. Demonstrations have shown that 5- to 10-mm-dia glass marbles can be encapsulated on an engineering scale with lead or lead alloys by gravity or vacuum processes. Marbles approx. 12 mm in dia were successfully encapsulated in a lead alloy on a production scale. Also, 4- to 9-mm-dia ceramic pellets in containers of various sizes were completely penetrated and the individual pellets encased with aluminum-12 wt % silicon alloy by vacuum processes. Indications are that of the casting processes tested, aluminum 12 wt % silicon alloy vacuum-cast around ceramic pellets had the highest degree of infiltration or coverage of pellet surfaces.

  20. DETAIL VIEW OF BASE OF CAST IRON TOWER SHOWING THE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    DETAIL VIEW OF BASE OF CAST IRON TOWER SHOWING THE FABRICATING MARK OF STARBUCK IRON WORKS, TROY, NY - Bidwell Bar Suspension Bridge & Stone Toll House, Near Lake Oroville (moved from fork of Feather River), Oroville, Butte County, CA