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1

CAST  

NSDL National Science Digital Library

The Council for Agricultural Science and Technology (CAST) was formed in 1972 as a result of a meeting sponsored by the National Academy of Sciences' National Research Council. CAST's mission is to "assemble, interpret, and communicate credible science-based information regionally, nationally, and internationally to legislators, regulators, policymakers, the media, the private sector and the public." Visitors will find the Education tab near the top of the page to be particularly helpful for those who want to pursue agricultural careers or learn about agricultural education, such as 4-H or Future Farmers of America. The CAST Videos section has a number of PowerPoint presentations on current topics of importance in agriculture, such as "The Science and Regulation of Food from Genetically Engineered Animals," "Food Safety and Fresh Produce," and "Probiotics in Human Health." A number of the papers that accompany the PowerPoint presentations are available for free.

2012-02-03

2

CAST  

NSDL National Science Digital Library

The Council for Agricultural Science and Technology (CAST) was formed in 1972 as a result of a meeting sponsored by the National Academy of Sciences' National Research Council. CAST's mission is to "assemble, interpret, and communicate credible science-based information regionally, nationally, and internationally to legislators, regulators, policymakers, the media, the private sector and the public." Visitors will find the Education tab near the top of the page to be particularly helpful for those who want to pursue agricultural careers or learn about agricultural education, such as 4-H or Future Farmers of America. The CAST Videos section has a number of PowerPoint presentations on current topics of importance in agriculture, such as "The Science and Regulation of Food from Genetically Engineered Animals," "Food Safety and Fresh Produce," and "Probiotics in Human Health." A number of the papers that accompany the PowerPoint presentations are available for free.

2012-02-06

3

Casting Technology.  

ERIC Educational Resources Information Center

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)

Wright, Michael D.; And Others

1992-01-01

4

Special Casting Techniques (Chapter 9).  

National Technical Information Service (NTIS)

Special casting techniques are progressive production methods. These casting techniques include the following: metal mold casting (chill mold casting), shell-mold casting, investment casting, centrifugal casting, and others. Each of these methods of casti...

N. P. Dubinin

1965-01-01

5

Paper Casting.  

ERIC Educational Resources Information Center

Describes an art project, based on the work of artist Chew Teng Beng, in the molding of wet paper on a plaster cast to create embossed paper designs. The values of such a project are outlined, including a note that its tactile approach makes it suitable to visually handicapped students. (SJL)

Arrasjid, Dorine A.

1980-01-01

6

Casting methods  

DOEpatents

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.

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

2012-12-18

7

Casting materials  

SciTech Connect

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.

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

8

Thin Wall Iron Castings  

SciTech Connect

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.

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

2001-10-31

9

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

10

High Performance Castings.  

National Technical Information Service (NTIS)

The report delineates the factors influencing the characteristics, design, and properties of high-performance castings and the outstanding problems that must be resolved to enhance the reliability and use of these castings. It suggests a number of program...

1972-01-01

11

LLNL casting technology  

SciTech Connect

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.

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

1994-01-01

12

LLNL casting technology  

NASA Astrophysics Data System (ADS)

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.

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

1994-01-01

13

The "flatback" cast.  

PubMed

A properly applied above-elbow cast in a child presents difficulties not seen in adults. Because of the differences in anatomy, physiology, and compliance, children can benefit from modification of the standard above-elbow cast. We report on a method of application of the "flatback" cast to address these concerns. PMID:8421630

Black, G B; Klippenstein, N L

1993-01-01

14

Casting and Molding  

NSDL National Science Digital Library

This activity was designed for blind learners, but all types of learners can explore the process used to cast and mold molten metal, glass, and plastics. Using gelatin, the learner will work with a variety of molds to create castings. When the shapes are unmolded, the learner can tactually explore the casts.

Blind, Perkins S.

2012-06-26

15

Advanced Cast Aluminum Alloys.  

National Technical Information Service (NTIS)

A recent advancement in cast aluminum alloys has demonstrated that complex shapes can be cast from a microalloyed Al-Cu alloy in dry sand molds with chills and that these castings can be heat treated to produce mechanical and physical properties nearly co...

A. P. Druschitz J. Griffin

2009-01-01

16

Improving Metal Casting Process  

NASA Technical Reports Server (NTRS)

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.

1998-01-01

17

Machine Casting of Ferrous Alloys.  

National Technical Information Service (NTIS)

The general purpose of the first six months' work was to identify techniques which will produce sound castings in reusable chill molds - techniques which are compatible with an automated machine casting process. To do this, castings made in permanent chil...

M. F. X. Gigliotti

1973-01-01

18

Casting Footprints for Eternity  

NASA Technical Reports Server (NTRS)

Apollo 11 Astronaut Buzz Aldrin has his footprints casted during the dedication ceremony of the rocket fountain at Building 4200 at Marshall Space Flight Center. The casts of Aldrin's footprints will be placed in the newly constructed Von Braun courtyard representing the accomplishments of the Apollo 11 lunar landing.

1999-01-01

19

Computer cast blast modelling  

Microsoft Academic Search

Cast blasting can be designed to utilize explosive energy effectively and economically for coal mining operations to remove overburden material. The more overburden removed by explosives, the less blasted material there is left to be transported with mechanical equipment, such as draglines and trucks. In order to optimize the percentage of rock that is cast, a higher powder factor than

S. Chung; M. McGill; D. S. Preece

1994-01-01

20

Clean Metal Casting  

SciTech Connect

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.

Makhlouf M. Makhlouf; Diran Apelian

2002-02-05

21

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

22

Optimum cast plan for steelmaking-continuous casting production scheduling  

Microsoft Academic Search

A planning method of cast for steelmaking continuous casting production scheduling in CIMS is studied. The cast plan model is established. An adaptive operator genetic algorithm is proposed to solve the optimum cast plan problem. The computation with practical data shows that the model and the solving method are very effective.

Yuncan Xue; Qiwen Yang; Huihe Shao

2004-01-01

23

Concrete Casting Machine.  

National Technical Information Service (NTIS)

The machine is for casting, on a production line basis, articulated concrete revetment mats employed to protect riverbanks and flood control levees from hydraulic erosion. The apparatus includes a moving conveyor system which carries flat pallets to a cas...

J. I. Boswell T. Burks G. F. Dixon G. S. Lee

1964-01-01

24

Cast changes: synthetic versus plaster.  

PubMed

A review of the changes in casting since the introduction of improved synthetic casting materials in the 1970s is presented. There is very little in the literature on nursing implications regarding the newer casting materials. Improvements in synthetic materials used in the casting of children include a fiberglass-free, latex-free casting polymer, with child-friendly prints now available. Though the use of synthetic casting predominates the market, plaster of Paris is still the mainstay for serial casting and casting requiring superior moldability and conformability. The advantages and disadvantages of synthetic and plaster of Paris casting, as well as nursing care of the child in each type of cast are summarized. PMID:9282058

Adkins, L M

1997-01-01

25

Casting Characteristics of Aluminum Die Casting Alloys  

SciTech Connect

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.

Makhlouf M. Makhlouf; Diran Apelian

2002-02-05

26

Method of casting aerogels  

DOEpatents

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.

Poco, J.F.

1993-09-07

27

Method of casting aerogels  

DOEpatents

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.

Poco, John F. (Livermore, CA)

1993-01-01

28

Bence Jones Cast Nephropathy  

Microsoft Academic Search

Patients with Bence Jones cast nephropathy usually present with acute renal failure (less commonly with chronic renal failure)\\u000a and Bence Jones proteinuria. It has been known for many years that intravenous radiocontrast media, dehydration, infections,\\u000a and the use of nonsteroidal antiin- fl ammatory drugs may induce the precipitation of renal tubular light chain casts and\\u000a result in acute renal failure,

Arthur H. Cohen

29

A Winning Cast  

NASA Technical Reports Server (NTRS)

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.

2001-01-01

30

Quartz ceramic nozzles for casting steel on continuous casting plant  

Microsoft Academic Search

Conclusions A technology was developed for making steel casting nozzles for the continuous casting of steel with different versions of lateral input of metal into the crystallizer. In laboratory conditions we made nozzles 600–650 mm long.

R. S. Churakova; E. P. Fedorova; Yu. A. Polonskii; E. I. Ermolaeva; A. M. Pozhivanov; N. D. Karpov

1972-01-01

31

Slip casting under pressure  

NASA Astrophysics Data System (ADS)

The addition of a pressure during slip casting increases the rate of material deposition and enables larger pieces to be fabricated. In this study, this process has been further developed using monolithic Al2O3 and Al2O3-SiC composites. Slip casting formulations based on both dispersed and coagulated slurries have been analyzed. Excellent results are achieved using coagulated slurries, with no cracking present after drying. The effect of pressure is to increase the green density with a consequent increase in the fired density. In addition, homogeneous microstructures are achieved in the composite system, despite the large difference in particle size used.

Grazzini, H. H.; Wilkinson, D. S.

1992-08-01

32

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

33

Pressure Casting in Investment Molds.  

National Technical Information Service (NTIS)

A study was made of methods for pressure casting nonferrous alloys into investment molds. The experimental methods were compared with standard suction casting practices. The best method studied was the direct pressure diaphragm method. By this method, met...

S. Lipson F. Ripkin

1964-01-01

34

Investment casting of gold jewellery  

Microsoft Academic Search

Changes in temperature which take place during pouring of a melt and flow into the mould vary greatly, and also depend on\\u000a the casting technique used. Understanding these changes is important for optimum casting practice.

Dieter Ott; Christoph J. Raub

1986-01-01

35

Sealing micropores in thin castings  

NASA Technical Reports Server (NTRS)

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.

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

1981-01-01

36

Rapid casting solutions: a review  

Microsoft Academic Search

Purpose – This paper seeks to review the industrial applications of state-of-the-art additive manufacturing (AM) techniques in metal casting technology. An extensive survey of concepts, techniques, approaches and suitability of various commercialised rapid casting (RC) solutions with traditional casting methods is presented. Design\\/methodology\\/approach – The tooling required for producing metal casting such as fabrication of patterns, cores and moulds with

Munish Chhabra; Rupinder Singh

2011-01-01

37

Casting Of Multilayer Ceramic Tapes  

NASA Technical Reports Server (NTRS)

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.

Collins, Earl R., Jr.

1991-01-01

38

BIMETALLIC CASTING. Final Report  

Microsoft Academic Search

Uranium and Zr were bonded by melting the two metals in contact with one ; another in a bimetallic casting process. Tensile tests of specimens containing ; the original zone of interface between the two metals showed that all failures ; were at locations other than the interface. The coefficients obtained for ; diffusion between molten U and molten Zr

T. Poole; D. Krashes

1962-01-01

39

ShakeCast Manual  

USGS Publications Warehouse

ShakeCast is a freely available, post-earthquake situational awareness application that automatically retrieves earthquake shaking data from ShakeMap, compares intensity measures against users? facilities, and generates potential damage assessment notifications, facility damage maps, and other Web-based products for emergency managers and responders.

Lin, Kuo-Wan; Wald, David J.

2008-01-01

40

Casting and Angling.  

ERIC Educational Resources Information Center

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…

Smith, Julian W.

41

Machine Casting of Ferrous Alloys.  

National Technical Information Service (NTIS)

A series of iron, nickel, and cobalt base alloys were permanent mold cast under varying conditions to evaluate techniques for improving the integrity of die casting. By appropriate control of heat flow it is possible to achieve permanent mold casting with...

M. F. X. Gigliotti

1974-01-01

42

Flow impact on cast ingots  

Microsoft Academic Search

Aluminium alloys are a standard cast metal used in a number of automotive and transportation applications, allowing manufacturers to reduce vehicle weight, increase the strength of components and improve emission controls. One of the most challenging problems associated with aluminium casting is the influence of convection during all stages of solidification. The strength of fluid flow changes the as-cast internal

Lorenz Ratke; Yves Fautrelle; Jacques Lacaze; Georg Müller; Andras Roosz; Gerhard Zimmermann; Phillippe Jarry; Rene Kieft; Zsolt Csepeli; Józef Sándor; Gerd-Ulrich Grün; Nándor Sillinger; Ralf Gerke-Cantow

2005-01-01

43

Mix/Cast Contamination Control  

NASA Technical Reports Server (NTRS)

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.

Wallentine, M.

2005-01-01

44

AMCC casting development, volume 2  

NASA Technical Reports Server (NTRS)

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.

1995-01-01

45

Volume MLS ray casting.  

PubMed

The method of Moving Least Squares (MLS) is a popular framework for reconstructing continuous functions from scattered data due to its rich mathematical properties and well-understood theoretical foundations. This paper applies MLS to volume rendering, providing a unified mathematical framework for ray casting of scalar data stored over regular as well as irregular grids. We use the MLS reconstruction to render smooth isosurfaces and to compute accurate derivatives for high-quality shading effects. We also present a novel, adaptive preintegration scheme to improve the efficiency of the ray casting algorithm by reducing the overall number of function evaluations, and an efficient implementation of our framework exploiting modern graphics hardware. The resulting system enables high-quality volume integration and shaded isosurface rendering for regular and irregular volume data. PMID:18988986

Ledergerber, Christian; Guennebaud, Gaël; Meyer, Miriah; Bächer, Moritz; Pfister, Hanspeter

2008-01-01

46

USGS ShakeCast  

USGS Publications Warehouse

Automating, Simplifying, and Improving the Use of ShakeMap for Post-Earthquake Decisionmaking and Response. ShakeCast is a freely available, post-earthquake situational awareness application that automatically retrieves earthquake shaking data from ShakeMap, compares intensity measures against users facilities, and generates potential damage assessment notifications, facility damage maps, and other Web-based products for emergency managers and responders.

Wald, David; Lin, Kuo-Wan

2007-01-01

47

Steel casting by diffusion solidification  

Microsoft Academic Search

A new process for casting and welding carbon steels is described in which carbon diffuses isothermally or adiabatically within\\u000a an intimate mixture of solid low carbon steel and high carbon liquid iron to effect solidification and subsequent homogenization\\u000a with respect to carbon. Advantages over conventional casting processes and products result from 1) 150 to 200‡C lower casting\\u000a temperature; 2) reduced

George Langford; Robert E. Cunningham

1978-01-01

48

Steel casting by diffusion solidification  

Microsoft Academic Search

A new process for casting and welding carbon steels is described in which carbon diffuses isothermally or adiabatically within\\u000a an intimate mixture of solid low carbon steel and high carbon liquid iron to effect solidification and subsequent homogenization\\u000a with respect to carbon. Advantages over conventional casting processes and products result from 1) 150 to 200°C lower casting\\u000a temperature; 2) reduced

George Langford; Robert E. Cunningham

1978-01-01

49

Cast dielectric composite linear accelerator  

DOEpatents

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.

Sanders, David M. (Livermore, CA) [Livermore, CA; Sampayan, Stephen (Manteca, CA) [Manteca, CA; Slenes, Kirk (Albuquerque, NM) [Albuquerque, NM; Stoller, H. M. (Albuquerque, NM) [Albuquerque, NM

2009-11-10

50

Lost-Soap Aluminum Casting.  

ERIC Educational Resources Information Center

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)

Mihalow, Paula

1980-01-01

51

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...

52

Casting Freedom, 1860-1862  

ERIC Educational Resources Information Center

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

Social Education, 2005

2005-01-01

53

Friction drilling of cast metals  

Microsoft Academic Search

This study investigates the friction drilling process, a nontraditional hole-making technique, for cast metals. In friction drilling, a rotating conical tool is applied to penetrate work-material and create a bushing in a single step without generating chip. The cast aluminum and magnesium alloys, two materials studied, are brittle compared to the ductile metal workpiece material used in previous friction drilling

Scott F. Miller; Jia Tao; Albert J. Shih

2006-01-01

54

Clogging in Continuous Casting Nozzles  

Microsoft Academic Search

Nozzle clogging is a serious productivity and qua lity problem in continuous casting. This work reviews the causes, effects, and solutions to cloggi ng in continuous casting nozzles. The results of a one-dimensional, steady state analysis of the heat loss from the molten steel stream through the nozzle wall are discussed. The analyses show that steel may freeze within the

K. G. Rackers; B. G. Thomas

55

An evaluation of fiberglass cast application techniques.  

PubMed

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

Wilson, D G; Vanderby, R

1995-01-01

56

Cast to Cast Variations in Type 316 Steel.  

National Technical Information Service (NTIS)

The microscopic examination of creep specimens from eight casts of AISI Type 316 stainless steel which ruptured with variable ductility is reported. The specimen microstructures are discussed and attempts are made to identify factors responsible for high ...

A. J. Hooper C. J. Bolton J. Lai J. E. Cordwell P. Marshall

1977-01-01

57

A Quantitative Approach to Casting Solidification: Freezing of Cast Iron.  

National Technical Information Service (NTIS)

The separate processes involved in casting solidification, such as eutectic nucleation and growth, have been previously studied separately in controlled experiments. The interaction of the separate processes has now been treated, using the freezing of cas...

W. Oldfield

1966-01-01

58

Instant Casting Movie Theater: The Future Cast System  

NASA Astrophysics Data System (ADS)

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.

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

59

Strip casting with fluxing agent applied to casting roll  

DOEpatents

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.

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

1997-07-29

60

Strip casting with fluxing agent applied to casting roll  

DOEpatents

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.

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

1997-01-01

61

Control of Cast Grain Size of Steel Castings.  

National Technical Information Service (NTIS)

Techniques for the quantative evaluation of refinement of a high strength cast steel have been evolved and used to test the effectiveness of various inoculants in achieving microstructural and macrostructural refinement. Of the various materials tested on...

P. Wieser N. Church J. F. Wallace

1964-01-01

62

Strip casting apparatus and method  

DOEpatents

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.

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

1988-01-01

63

Strip casting apparatus and method  

DOEpatents

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. 6 figs.

Williams, R.S.; Baker, D.F.

1988-09-20

64

Rapid Manufacturing Via Metal Casting  

NSDL National Science Digital Library

The metal casting industry in undergoing significant changes and it is necessary for manufacturing engineering, industrial engineering and design students to recognize these changes. Rapid manufacturing has the potential to revolutionize the metal casting industry by greatly reducing the tooling requirements necessary to produce components. The lead times to produce complex components are being reduced from months to days. A large reduction in the traditional labor requirements for molders, coremakers, patternmakers, and toolmakers will occur. The numerous advantages of the process are discussed and the major limitations are also presented. The "Third Wave" has arrived in the metal casting industry.

Creese, Robert

2009-07-14

65

Biomimetic Materials by Freeze Casting  

NASA Astrophysics Data System (ADS)

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.

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

2013-06-01

66

Investment casting design of experiment. Final report  

SciTech Connect

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.

Owens, R.

1997-10-01

67

Machine Casting of Ferrous Alloys.  

National Technical Information Service (NTIS)

Emphasis of the work at the University of Illinois is on processes and casting systems which employ a partially solid alloy as charge material. The program at the University of Illinois is especially designed to establish the processing conditions necessa...

R. Mehrabian D. G. Backman G. J. Abbaschian Y. V. Murty S. D. E. Ramati

1977-01-01

68

A New 'Shell Casting' Technic.  

National Technical Information Service (NTIS)

A new shell investment was formulated that hardened rapidly enough so that consecutive layers could be applied to a wax pattern without requiring intermediate drying cycles between each layer. This new 'shell casting investment' is a two component system....

E. R. Dootz R. G. Craig F. A. Peyton

1966-01-01

69

Care of Casts and Splints  

MedlinePLUS

... support. Casts can be made of plaster or fiberglass — a plastic that can be shaped. Splints or ... to put on, take off, and adjust. Materials Fiberglass or plaster materials form the hard supportive layer ...

70

Casting Using A Polystyrene Pattern  

NASA Technical Reports Server (NTRS)

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.

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

1993-01-01

71

Investment casting of gold jewellery  

Microsoft Academic Search

Porosity is one of the important causes for the rejection of jewellery items cast by the lost wax process. If it is of the\\u000a shrinkage type, then there is a considerable reservoir of knowledge, arising from experience in the casting of dental gold\\u000a and other gold alloys, which can be drawn upon to overcome the problem. If it is gas

Dieter Ott; Christoph J. Raub; William S. Rapson

1985-01-01

72

Titan Casts Revealing Shadow  

NASA Astrophysics Data System (ADS)

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,

2004-05-01

73

STME T/C casting technology  

NASA Astrophysics Data System (ADS)

The T/C casting technology developed by the National Launch System for the Space Transportation Main Engine is described. Special attention is given to the selection of JBK-75 as the combustion chamber casting alloy, some unique casting issues, and the development castings which were produced. Current plans call for producing a 650K full cast jacket mockup in the 4500 pound furnace. Once a 650K mockup casting has been successfully produced, a design of experiments (DOE) will be conducted to establish the best gating system. This will be followed by the design of permanent wax pattern tooling, gating tooling, and process fixtures, and, finally, by a process DOE.

Lobitz, J. R.; Ackerman, P. C.; Weber, S. L.

1992-07-01

74

Morphological castes in a vertebrate  

PubMed Central

Morphological specialization for a specific role has, until now, been assumed to be restricted to social invertebrates. Herein we show that complete physical dimorphism has evolved between reproductives and helpers in the eusocial naked mole-rat. Dimorphism is a consequence of the lumbar vertebrae lengthening after the onset of reproduction in females. This is the only known example of morphological castes in a vertebrate and is distinct from continuous size variation between breeders and helpers in other species of cooperatively breeding vertebrates. The evolution of castes in a mammal and insects represents a striking example of convergent evolution for enhanced fecundity in societies characterized by high reproductive skew. Similarities in the selective environment between naked mole-rats and eusocial insect species highlight the selective conditions under which queen/worker castes are predicted to evolve in animal societies.

O'Riain, M. J.; Jarvis, J. U. M.; Alexander, R.; Buffenstein, R.; Peeters, C.

2000-01-01

75

Casting propellant in rocket engine  

NASA Technical Reports Server (NTRS)

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.

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

1976-01-01

76

Cementite Solidification in Cast Iron  

NASA Astrophysics Data System (ADS)

Two hypereutectic cast irons (5.01 pct Cr and 5.19 pct V) were cast and the polished surfaces of test pieces were deep-etched and analyzed via scanning electron microscopy. The results show that graphite lamellae intersect the cementite and a thin austenite film nucleates and grows on the cementite plates. For both compositions, graphite and cementite can coexist as equilibrium phases, with the former always nucleating and growing first. The eutectic carbides grow from the austenite dendrites in a direction perpendicular to the primary plates.

Coronado, J. J.; Sinatora, A.; Albertin, E.

2014-06-01

77

Cementite Solidification in Cast Iron  

NASA Astrophysics Data System (ADS)

Two hypereutectic cast irons (5.01 pct Cr and 5.19 pct V) were cast and the polished surfaces of test pieces were deep-etched and analyzed via scanning electron microscopy. The results show that graphite lamellae intersect the cementite and a thin austenite film nucleates and grows on the cementite plates. For both compositions, graphite and cementite can coexist as equilibrium phases, with the former always nucleating and growing first. The eutectic carbides grow from the austenite dendrites in a direction perpendicular to the primary plates.

Coronado, J. J.; Sinatora, A.; Albertin, E.

2014-04-01

78

Cast-a-Box: Casting Conditions and Macroporosity  

NSDL National Science Digital Library

An illustration of three-dimensional finite difference simulation of heat conduction with phase change and complex boundary conditions, this requires students to adjust boundary conditions to make the top surface of a regular hexahedral "casting" to freeze last, eliminating macroporosity.

Powell, Adam C., IV

2004-08-24

79

Casting behavior of titanium alloys in a centrifugal casting machine.  

PubMed

Since dental casting requires replication of complex shapes with great accuracy, this study examined how well some commercial titanium alloys and experimental titanium-copper alloys filled a mold cavity. The metals examined were three types of commercial dental titanium [commercially pure titanium (hereinafter noted as CP-Ti), Ti-6Al-4V (T64) and Ti-6Al-7Nb (T67)], and experimental titanium-copper alloys [3%, 5% and 10% Cu (mass %)]. The volume percentage filling the cavity was evaluated in castings prepared in a very thin perforated sheet pattern and cast in a centrifugal casting machine. The flow behavior of the molten metal was also examined using a so-called "tracer element technique." The amounts of CP-Ti and all the Ti-Cu alloys filling the cavity were similar; less T64 and T67 filled the cavity. However, the Ti-Cu alloys failed to reach the end of the cavities due to a lower fluidity compared to the other metals. A mold prepared with specially designed perforated sheets was effective at differentiating the flow behavior of the metals tested. The present technique also revealed that the more viscous Ti-Cu alloys with a wide freezing range failed to sequentially flow to the end of the cavity. PMID:12593955

Watanabe, K; Miyakawa, O; Takada, Y; Okuno, O; Okabe, T

2003-05-01

80

New Lubricant for Pressure Die Casting.  

National Technical Information Service (NTIS)

Three lubricant formulations for the pressure die casting of large and complex castings were developed. The lubricants include mineral oils, synthetic acids, finely dispersed graphite preparations, etc. The new lubricants are not inferior in their propert...

B. P. Khrenov L. A. Tabanov L. Y. Kisilenko V. V. Romanov

1972-01-01

81

Welding of Castings in the Mining Environment.  

National Technical Information Service (NTIS)

The paper reviews the types of steel castings available to, and used in, the mining industry. The welding properties of carbon manganese, low alloy, and austenitic manganese steel castings are considered, and reference is made to the selection of welding ...

L. J. Lalor

1977-01-01

82

Metal Casting: Industry of the Future.  

National Technical Information Service (NTIS)

This 8-page brochure describes the Office of Industrial Technologies Metal Casting Industry of The Future; a partnership between the Department of Energy and the metal casting industry established to increase industrial energy and cost efficiency.

2001-01-01

83

The Role of Water in Slip Casting.  

National Technical Information Service (NTIS)

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. ...

R. A. Mccauley G. W. Phelps

1984-01-01

84

Electrochemical Etching of Titanium-Alloy Castings.  

National Technical Information Service (NTIS)

This study was conducted to determine whether a potentiostatic electrochemical method could be used to etch selectively either the dendrites or the interdendritic material from Ti cast structures and thereby reveal their microstructures. Cast binary titan...

J. C. Griess S. A. David R. J. Gray C. W. Houck

1983-01-01

85

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

86

New fibreglass casting system in orthopaedic practice.  

PubMed

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

Davis, B; Dooley, B

1976-06-26

87

Effect of ferrite on cast stainless steels  

SciTech Connect

Premature failure of stainless steel castings in bleach washing service is attributed to poor casting quality high porosity and to a high ferrite content, which makes the castings susceptible to corrosion by hot acid chloride solutions. A survey of the chemical compositions and ferrite contents of corrosion-resistant castings in bleach plants at three pulp mills found high [delta]-ferrite levels in the austenitic matrix due to the improper balance between austenite and ferrite stabilizers.

Nadezhdin, A.; Cooper, K. (Noranda Technology Centre, Pointe Claire, Quebec (Canada)); Timbers, G. (James Maclaren Inc., Quebec (Canada). Kraft Pulp Division)

1994-09-01

88

Porosity formation in axi-symmetric castings produced by counter-pressure casting method  

Microsoft Academic Search

We propose a method for simultaneous treatment of heat and mass transfer processes and porosity formation of castings produced by Counter Pressure Casting (CPC) method. The method enables us to account for the influence of the CPC parameters on the mechanical properties of the casting. Numerical results and comparison with experimental data are given for an axis-symmetric casting (hemisphere with

I. H. Katzarov; Y. B. Arsov; P. Stoyanov; T. Zeuner; A. Buehrig-Polaczek; P. R. Sahm

2001-01-01

89

Pressure Rig for Repetitive Casting.  

National Technical Information Service (NTIS)

The invention relates to a pressure rig for repetitive casting of metals. The pressure rig performs like a piston for feeding molten metal into a mold. Pressure is applied to an expandable rubber diaphragm which expands like a balloon to force the metal i...

P. Vasquez W. R. Hutto A. R. Philips

1987-01-01

90

Benchmarking aluminium die casting operations  

Microsoft Academic Search

Increasing demand in world automotive markets for aluminium die cast components is creating significant opportunities and challenges for the Australian industry, which is positioning itself as a global player. To meet these challenges, the industry is continuously seeking to improve its overall resource efficiency that can result in the reduction of cost and impact on green house gas (GHG) emissions.

A. Tharumarajah

2008-01-01

91

Homogenization heat treating cast microstructure  

NSDL National Science Digital Library

Cast microstructures have variations in composition on the length scale of dendrites and homogenization heat treatments are performed to smooth out these variations. This problem is an integral analysis of the 1D diffusion mass transfer in this problem. The results using two different assumed profiles are compared.

Krane, Matthew J.

2008-10-25

92

Advanced Lost Foam Casting Technology  

SciTech Connect

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

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

2000-11-30

93

Machine Casting of Ferrous Alloys.  

National Technical Information Service (NTIS)

This is the first semi-annual report describing research conducted at the University of Illinois at Urbana-Champaign as part of a joint university-industry research program on machine casting of ferrous alloys. During the six months covered by this report...

D. G. Backman R. Mehrabian R. J. Lauf S. D. E. Ramati Y. V. Murty

1976-01-01

94

Molding A Cast Metals Program  

ERIC Educational Resources Information Center

The cast metals program, a two-year associate degree program, at Muskegon Community College, Musegon, Michigan operates in close cooperation with the local foundry industry to provide a background for entry-level technical jobs and for continued studies toward a four-year degree. (EA)

Trumble, Dale E.

1975-01-01

95

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...

96

Tape casting of magnesium oxide.  

SciTech Connect

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.

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

2008-02-01

97

Machine Casting of Ferrous Alloys.  

National Technical Information Service (NTIS)

Due to the lack of economic permanent die materials for use in Hipocasting ferrous alloys, three innovative approaches for creating a mold cavity for use in machine casting of ferrous alloys were explored. They were: use of liquid metal cooling of a thin ...

G. D. Chandley G. Scholl

1975-01-01

98

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,...

99

Investment casting of gold jewellery  

Microsoft Academic Search

Measurements made by a very simple method have shown that many of the factors which affect the quality of castings are sensitive\\u000a to surface and interfacial energies during the pouring of the melt. The results of a number of measurements of these parameters\\u000a are presented and discussed.

Dieter Ott; Christoph J. Raub

1985-01-01

100

Investment casting of gold jewellery  

Microsoft Academic Search

The efficiency with which the moulds are filled is one of the most important aspects in the lost wax procedure for casting\\u000a jewellery. The factors which affect it are briefly discussed and the results of a number of experiments aimed at increasing\\u000a knowledge of the complex interrelationships between them are presented.

Dieter Ott; Christoph J. Raub

1986-01-01

101

Prediction of Microporosity in Shrouded Impeller Castings  

SciTech Connect

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.

Viswanathan, S. Nelson, C.D.

1998-09-01

102

Diabetic Neuropathy: What is a Total Contact Cast?  

MedlinePLUS

... 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 ( ... foot--that's why it is called a total contact cast. The cast helps to protect the skin ...

103

Land-based turbine casting initiative  

SciTech Connect

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.

Mueller, B.A.; Spicer, R.A. [Howmet Corp., Whitehall, MI (United States)

1995-12-31

104

Viscosity of casting fluxes used during continuous casting of steel  

Microsoft Academic Search

Molten flux viscosity of eighteen commercially available casting fluxes has been measured as a function of temperature in\\u000a the range of 1223 to 1723 K. Results show that, at a constant temperature, the flux viscosity is primarily dependent on the\\u000a mole fractions of SiO2 and A12O3. The calculated activation energy for viscous flow at 1573 K varies from 59 to

Michael D. Lanyi; Casimir J. Rosa

1981-01-01

105

Emulsion based cast booster - a priming system  

SciTech Connect

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.

Gupta, R.N.; Mishra, A.K. [National Institute of Rock Mechanics, KGF (India)

2005-07-01

106

Focused rigidity casts: an overview.  

PubMed

Focused rigidity casts (FRCs) are a novel treatment made from polymer semi-flexible cast material, used in the management of plantar foot ulceration to offload the site of ulceration. Current anecdotal evidence suggests that use of FRCs helps achieve quicker healing time. While FRCs were first used in the treatment of fractures, previous reports suggest that the FRC may be effective in the treatment of plantar foot ulceration. Although there is a paucity of evidence to support the use of FRCs in the treatment of foot ulceration, current evidence demonstrates a decrease in both wound healing time and plantar pressure. The aim of the paper is to examine the importance of offloading plantar ulcerations and introduce FRCs. PMID:23665658

Dagg, A R; Chockalingam, N; Branthwaite, H

2013-02-01

107

Casting Alloys: Side-Effects  

Microsoft Academic Search

Side-effects from dental materials are a minor problem, but should be recognized. In recent questionnaire surveys about side-effects, the incidence was estimated to be 1:300 in periodontics and 1:2600 in pedodontics. None of these reactions was related to dental casting alloys. In prosthodontics, the incidence was calculated to be about 1:400, and about 27% were related to base-metal alloys forremovable

Arne Hensten-Pettersen

1992-01-01

108

Investment casting of gold jewellery  

Microsoft Academic Search

The lost wax or investment casting process used extensively in gold jewellery fabrication is subject to the effects of a large\\u000a number of process variables. One consequence of this is that where problems arise or exist in its application, they can be\\u000a difficult to understand and solve. In order to promote optimization of the process the authors have studied the

Dieter Ott; Christoph J. Raub

1985-01-01

109

Tape casting of lanthanum chromite  

SciTech Connect

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.

Murphy, M.W.; Armstrong, T.R.; Smith, P.A. [Pacific Northwest National Lab., Richland, WA (United States)

1997-01-01

110

Aging degradation of cast stainless steel  

Microsoft Academic Search

A program is being conducted to investigate the significance of in-service embrittlement of cast-duplex stainless steels under light-water reactor operating conditions. Data from room-temperature Charpy-impact tests for several heats of cast stainless steel aged up to 10,000 h at 350, 400, and 450°C are presented and compared with results from other studies. Microstructures of cast-duplex stainless steels subjected to long-term

O. K. Chopra; H. M. Chung

1985-01-01

111

A Benchmark Study on Casting Residual Stress  

SciTech Connect

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.

Johnson, Eric M. [John Deere -- Moline Tech Center; Watkins, Thomas R [ORNL; Schmidlin, Joshua E [ORNL; Dutler, S. A. [MAGMA Foundry Technologies, Inc.

2012-01-01

112

Gating of Permanent Molds for Aluminum Casting  

Microsoft Academic Search

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

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

2004-01-01

113

Directional Solidification of Nodular Cast Iron  

NASA Technical Reports Server (NTRS)

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.

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

1987-01-01

114

High-Density-Tape Casting System  

NASA Technical Reports Server (NTRS)

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.

Collins, Earl R., Jr.

1987-01-01

115

Cutting efficiency of air-turbine burs on cast titanium and dental casting alloys  

Microsoft Academic Search

Objective: The purpose of this study was to investigate the cutting efficiency of air-turbine burs on cast free-machining titanium alloy (DT2F) and to compare the results with those for cast commercially pure (CP) Ti, Ti–6Al–4V alloy, and dental casting alloys.Methods: The cast metal (DT2F, CP Ti, Ti–6Al–4V, Type IV gold alloy and Co–Cr alloy) specimens were cut with air-turbine burs

I Watanabe; C Ohkubo; J. P Ford; M Atsuta; T Okabe

2000-01-01

116

Spray casting project final report  

SciTech Connect

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.

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

1996-08-01

117

Titanium and titanium alloy castings  

SciTech Connect

The specification covers ten grades of unalloyed titanium and titanium alloy castings as follows: Grade C-1, C-2, C-3, and C-4 (unalloyed titanium, Grade C-5 (Ti-6Al-4V), Grade C-6 (Ti-5Al-2.5Sn), Grade C-7A, C-7B, C-8A, and C-8B (Ti-Pd). The specification includes ordering information, manufacture, chemical composition, sampling and methods of chemical analysis, tensile properties, hardness, nondestructive inspection, workmanship, finish, marking, and certification. (JMT)

Not Available

1981-01-01

118

Control of cast iron microstructure  

NASA Technical Reports Server (NTRS)

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.

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

1985-01-01

119

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...

120

Yield Improvement in Steel Casting (Yield II)  

SciTech Connect

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

Richard A. Hardin; Christoph Beckermann; Tim Hays

2002-02-18

121

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

122

Continuous Steel Casting into Shaped Blanks (Selected Portions).  

National Technical Information Service (NTIS)

The introduction into the metallurgical industry of the method of continuous casting became possible only after the development of a stable casting process which provided stability for metallurgical production and obtaining high-grade production from cast...

D. P. Evteev N. A. Nikolaev N. N. Guglin V. S. Rutes Y. Y. Kan

1971-01-01

123

21 CFR 888.5960 - Cast removal instrument.  

Code of Federal Regulations, 2010 CFR

... 2010-04-01 2010-04-01 false Cast removal instrument. 888.5960 Section...DEVICES Surgical Devices § 888.5960 Cast removal instrument. (a) Identification. A cast removal instrument is an AC-powered,...

2010-04-01

124

Grease for Casting Aluminum Alloys under Pressure.  

National Technical Information Service (NTIS)

A grease is described for use with die casting molds and adjacent hot parts of casting machines consisting of an oxidized petrolatum (containing smaller than or equal to 16% hydroxy acids) base material aluminum powder 1.5-1.7, flaky graphite 0.5-3.0, and...

A. I. Dintses G. B. Solomonik N. N. Belousov R. N. Osher T. M. Komissarova

1972-01-01

125

Light weight design with light metal castings  

Microsoft Academic Search

The article gives a number of examples of light weight design with aluminium and magnesium castings. The high perfection of the high-pressure die casting HPDC technology and new design opportunities for net shape or near net shape components will be presented. New applications of particle reinforced light metals offer additional potential for weight saving and better technical, economical and environmental

D Brungs

1997-01-01

126

Automated Radioscopic Inspection of Aluminum Die Castings  

Microsoft Academic Search

Castings produced for the automotive industry are c onsidered important components for overall roadworthiness. To ensure the safety of con struction, it is necessary to check every part thoroughly using non-destructive testing . Radioscopy rapidly became the accepted way for controlling the quality of die cas t pieces. In this paper the fundamental principles of the automated detection of casting

Domingo Mery

127

Blast casting requires fresh assessment of methods  

SciTech Connect

The article says that because blast casting differs from conventional blasting, our ideas about explosive products, drilling, and initiating methods must change. The author discusses how to select a casting explosive and what factors are important in its selection. He also looks at how to determine the best blasthole diameter and burden blasting pattern.

Pilshaw, S.R.

1987-08-01

128

Composites for Advanced Space Transportation Systems (CASTS).  

National Technical Information Service (NTIS)

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 ap...

J. G. Davis

1979-01-01

129

Thermomechanical model of a continuous casting process  

Microsoft Academic Search

A model for the analysis of thermal stresses arising at the early stage of a continuous casting process is proposed. The model is used to simulate the casting of round billets assuming axial symmetry. Thermal analysis takes into account phase-change in the material and heat transfer through the mould. The heat balance equation is solved using an Eulerian formulation for

A. E. Huespe; A. Cardona; V. Fachinotti

2000-01-01

130

Iron/Phosphorus Alloys for Continuous Casting  

NASA Technical Reports Server (NTRS)

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.

Dufresne, E. R.

1986-01-01

131

Slip casting and nitridation of silicon powder  

NASA Astrophysics Data System (ADS)

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.

Seiko, Y.

1985-03-01

132

The CAST (Childhood Asperger Syndrome Test)  

ERIC Educational Resources Information Center

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…

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

2005-01-01

133

Subcritical Measurments Multiple HEU Metal Castings  

SciTech Connect

Experiments with the standard annular highly enriched uranium (HEU) metal castings at the Y-12 National Security Complex were performed in which up to five castings ({approx}90 kg) were assembled in a tightly packed array with minimal spacing between castings. The fission chain multiplication process was initiated by a time-tagged {sup 252}Cf spontaneously fissioning neutron source or by time and directionally tagged neutrons from a small portable DT neutron generator. The prompt neutron time behavior was measured with plastic scintillation detectors sensitive to the fast neutron (>1 MeV) and gamma ray without distinction. These experiments were performed to provide data to benchmark methods for the calculation of the prompt neutron time behavior. Previous measurements with a single casting have been reported. This paper presents the experimental results for multiple castings.

Mihalczo, John T [ORNL] [ORNL; Archer, Daniel E [ORNL] [ORNL; Wright, Michael C [ORNL] [ORNL; Mullens, James Allen [ORNL] [ORNL

2008-01-01

134

The production of large structural titanium castings  

NASA Astrophysics Data System (ADS)

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.

Klepeisz, J.; Veeck, S.

1997-11-01

135

Final report on Expendable Pattern Casting Technology  

SciTech Connect

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.

Not Available

1990-07-01

136

Porosity inside a metal casting  

NASA Technical Reports Server (NTRS)

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.

2003-01-01

137

AMCC casting development. Volume 1: Executive Summary  

NASA Technical Reports Server (NTRS)

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).

1995-01-01

138

Subcritical Measurements Multiple HEU Metal Castings  

SciTech Connect

Experiments with the standard annular highly enriched uranium (HEU) metal castings at Y-12 were performed in which up to 5 castings ({approx}90kg) were assembled in a tightly packed array with minimal spacing between castings. The fission chain multiplication process was initiated by a time tagged {sup 253}Cf spontaneously fissioning neutron source or time and directionally tagged neutrons from a small portable DT neutron generator and the prompt neutron time behavior measured with plastic scintillation detectors sensitive the fast neutron (>1 MeV) and gamma ray without distinction. These experiments were performed to provide data to benchmark methods for the calculation of the prompt neutron time behavior. Previous measurements with a single casting have been reported. This paper presents the experimental results for multiple castings. The prompt time decay was obtained by time coincidence correlation measurements between the detectors and the time tagged neutron source emission (equivalent to randomly pulsed neutron measurements) and between pairs of plastic scintillation detectors (equivalent to a 2-detector Rossi-alpha measurement). These standard HEU storage castings at the Y-12 plant had 5.000-in-OD, 3.500-in-ID, masses between 17,636 and 17,996 g, impurity content of 992 ppm, density of 18.75 g/cm{sup 3} and average enrichment of 93.16 wt % {sup 235}U. The castings were in tight fitting 025-in.-thick, 8.0-in-high stainless steel (SS-304) cylindrical cans for contamination control which were 8.0 in high. One can had an inside diameter of 3.0 in so that the Cf source could be located on the axes of this casting. Four 1 x 1 x 6 in plastic scintillators with the long dimension perpendicular to axes of the castings and adjacent to the outer surface of the casting cans were used. The detectors were enclosed in 1/4.-in.-thick lead shields on four 1 x 6 surfaces and on the 1 x 1 surface. The small surface of the lead shield was adjacent to the steel table. The photograph of the assembly of 5 casting with the detectors is given in Figure 1. The DT generator can be seen in the back with the time tagged neutrons aligned symmetrically around a line drawn from the generator through target spot and the center of the casting in the annular can seen in the foreground.

Mihalczo, John T [ORNL] [ORNL; Archer, Daniel E [ORNL] [ORNL; Wright, Michael C [ORNL] [ORNL

2008-01-01

139

Methods for Casting Subterranean Ant Nests  

PubMed Central

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.

Tschinkel, Walter R.

2010-01-01

140

Die-casting powdery mold releasing agent  

US Patent & Trademark Office Database

A die-casting powdery mold releasing agent according to this invention is a mold releasing agent comprising a mixture of powdery or granulated mold releasing base material composed of an inorganic compound as used for lubricant in a solid form and an organic compound giving adhesive property to the mold releasing agent, the both having powdery or granulated configurations, or configurations in which the organic compound is covered on the mold releasing base material. The mold releasing agent allows production of castings of high quality, in the die-casting method with good workability and without worsening environmental situations.

1991-08-13

141

Aluminium–aluminium compound fabrication by high pressure die casting  

Microsoft Academic Search

This study examines the development of aluminium–aluminium compounds during high pressure die casting. An aluminium insert was mounted into a die casting mould and embedded into an aluminium casting alloy. Prior to that, the natural oxide layer of the insert was removed and replaced by zinc coatings with different thicknesses. During the casting process the zinc layer dissolves and a

M. Rübner; M. Günzl; C. Körner; R. F. Singer

2011-01-01

142

Heritability of Anthropometric Phenotypes in Caste Populations of Visakhapatnam, India  

Microsoft Academic Search

6 Abstract In this study, we used anthropometric data from six Andhra caste populations to examine heritability patterns of 23 anthropometric phe- notypes (linear, craniofacial, and soft tissue measures) with special reference to caste differences. We obtained anthropometric data from 342 nuclear fam- ilies from Brahmin, Reddy, Telaga, Nagara, Ag. Kshatriya, and Mala castes of Visakhapatnam, India. These caste groups

Rector Arya; Ravindranath Duggirala; Anthony G. Comuzzie; Sobha Puppala; Saileela Modem; Bhaskara R. Busi; Michael H. Crawford

2002-01-01

143

Heritability of Anthropometric Phenotypes in Caste Populations of Visakhapatnam, India  

Microsoft Academic Search

In this study, we used anthropometric data from six Andhra caste populations to examine heritability patterns of 23 anthropometric phenotypes (linear, craniofacial, and soft tissue measures) with special reference to caste differences. We obtained anthropometric data from 342 nuclear families from Brahmin, Reddy, Telaga, Nagara, Ag. Kshatriya, and Mala castes of Visakhapatnam, India. These caste groups represent the existing hierarchical

Rector Arya; Ravindranath Duggirala; Anthony G. Comuzzie; Sobah Puppala; Saileela Modem; Bhaskara R. Busi; Michael H. Crawford

2011-01-01

144

Investment cast AISI H13 tooling for automotive applications.  

National Technical Information Service (NTIS)

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 mate...

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

1995-01-01

145

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

ERIC Educational Resources Information Center

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…

Zebco, Tulsa, OK.

146

[Comparative studies of synthetic and nonsynthetic cast dressings].  

PubMed

Six different cast materials were evaluated and compared for radiolucency and mechanical properties. Synthetic casts, that do not contain fiberglass are more radiolucent than fiberglass cast materials or plaster of Paris. The fiberglass cast is particularly stable, and the advantage of the cotton cast is a low dead weight. The costs of synthetic casts made according to the producer manufacturers' recommendations do not differ significantly, but they are all much more expensive than plaster of Paris. Splitting a synthetic cast along its length and bending it open is not enough to prevent compartment syndrome, and wedging is recommended to keep it open. PMID:8073300

Kunze, K; Haberer, K H

1994-06-01

147

Feeding and Risering Guidelines for Steel Castings.  

National Technical Information Service (NTIS)

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, a...

2002-01-01

148

Electric Heating for Pressure Die Casting Nozzles.  

National Technical Information Service (NTIS)

The possibility of using electric heating of magnesium pressure die casting nozzles has been investigated. Temperature calculations were carried out which indicated its feasibility. A test rig was built and temperature gradients in a full size nozzle were...

R. Stevens

1977-01-01

149

Microstructural Characterization of Cast Nickel Aluminum Bronze.  

National Technical Information Service (NTIS)

The morphology and chemical analysis of the complex phases present in cast nickel aluminum bronze of nominal composition 10% aluminum, 5% nickel, and 5% iron were investigated using optical microscopy, scanning electron microscopy, and scanning transmissi...

E. A. Culpan G. Rose

1978-01-01

150

Measurement of breast volume with thermoplastic casts.  

PubMed

A pilot study was carried through to assess the reproducibility of a new method of measuring breast volume. Twenty healthy female volunteers participated. A negative replica of the breast was made with thermoplastic cast material. The volume was measured by filling the cast with water until it reached two opposite points of the boundaries of the breast delineated on the cast. Three measurements were made of every cast and the mean was calculated. The range of the three measurements expressed as a percentage of the mean volume was 2.9 (SD 1.6)%. Each volunteer's breasts were measured twice with a brief intervening pause. The coefficient of variation between the two corresponding measurements was 6%. PMID:8815982

Edsander-Nord, A; Wickman, M; Jurell, G

1996-06-01

151

Recovery of Zircon from Investment Casting Molds.  

National Technical Information Service (NTIS)

The Bureau of Mines conducted physical and chemical beneficiation studies on three samples of waste investment casting molds to devise a method to liberate and recover zircon. Rod mill grinding, autogenous attrition grinding, and caustic leaching were lib...

C. W. Smith T. O. Llewellyn

1985-01-01

152

Uranium casting furnace automatic temperature control development.  

National Technical Information Service (NTIS)

Development of an automatic molten uranium temperature control system for use on batch-type induction casting furnaces is described. Implementation of a two-color optical pyrometer, development of an optical scanner for the pyrometer, determination of fur...

R. F. Lind

1992-01-01

153

Advanced lost foam from casting technology  

SciTech Connect

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.

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

1996-05-01

154

Thermal transport properties of grey cast irons  

SciTech Connect

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.

Hecht, R.L. [Ford Motor Co., Dearborn, MI (United States). Ford Research Lab.; Dinwiddie, R.B.; Porter, W.D.; Wang, Hsin [Oak Ridge National Lab., TN (United States)

1996-10-01

155

Slip casting alumina with Na-CMC  

SciTech Connect

Many forming methods are in common use for engineering ceramics. Of these, slip casting is an ideal forming method because of its low cost, simplicity and flexibility, potential for uniform particle packing and suitability to the production of articles of intricate shape. Slip casting nonclay materials, such as alumina, requires the use of both a deflocculant and a binder. There are many commercially available deflocculants and binders that can be tested in alumina casting slips. However, determination of a suitable deflocculant/binder combination and quantification of the optimal additions of the deflocculant/binder pair can be time consuming. Certain deflocculants are capable of acting as binders. One such additive is sodium carboxymethylcellulose (Na-cmc), a cellulose ether. Na-cmc is a powerful binder. It is a member of the carbohydrate binder group--the binder group with the strongest binding power. It is capable of acting as a deflocculant in glazes and nonclay casting slips.

Ruys, A.J.; Sorrell, C.C. [Univ. of New South Wales, Sydney, New South Wales (Australia)

1996-11-01

156

Caste and Language in Jaffna Society.  

ERIC Educational Resources Information Center

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)

Suseendirarajah, S.

1978-01-01

157

Vacuum casting of thick polymeric films  

NASA Technical Reports Server (NTRS)

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.

Cuddihy, E. F.; Moacanin, J.

1979-01-01

158

Genetic structure of Rajaka caste and affinities with other caste populations of Andhra Pradesh, India.  

PubMed

The present study gives an account of the genetic structure in terms of distribution of a few genetic markers, viz., A1A2B0, Rh(D), G6PD deficiency and haemoglobin among the Rajaka caste population of Andhra Pradesh, India. The genetic relationships of the Rajaka caste with other Andhra caste populations were investigated in terms of genetic distance, i.e., Sq B (mn) of Balakrishnan and Sanghvi. Relatively lesser distance was established between the Rajaka and two Panchama castes. Also, the pattern of genetic distance corroborates the hierarchical order of the Hindu varna system. PMID:9428195

Parvatheesam, C; Babu, B V; Babu, M C

1997-01-01

159

Effect of casting methods on castability of pure titanium.  

PubMed

Two types of patterns were tested for castability: 1) polyester mesh pattern (20mm x 22mm with 100 open squares) and 2) 20mm x 20mm wax plates 1.0 and 1.5 mm in thickness. These materials were invested using a pre-arranged commercial phosphate-bonded investment for titanium. Three different types of casting machines were selected: 1) a pressure-type casting machine with separate melting and casting chambers, 2) a pressure-type casting machine with one chamber and 3) a centrifugal-type casting machine at 3000 rpm. Pure titanium (> 99.5%) was cast into the molds at a mold temperature of 100 degrees C. The castability of mesh pattern was evaluated in terms of the number of cast segment, and the cast plate was evaluated using X-ray transparent images by a digital imaging technique. The centrifugal casting method showed the best castability among these three casting methods. PMID:8004920

Takahashi, J; Zhang, J Z; Okazaki, M

1993-12-01

160

Embedding Optical Fibers In Cast Metal Parts  

NASA Technical Reports Server (NTRS)

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.

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

1995-01-01

161

Physiology as a caste-defining feature  

Microsoft Academic Search

.  Division of labour is a key factor in the ecological success of social insects. Groups of individuals specializing on a particular\\u000a behaviour are known as castes and are usually distinguished by morphology or age. Physiology plays a key role in both these\\u000a types of caste, in either the developmental physiology which determines morphology, or the temporal changes in physiology\\u000a over

E. J. H. Robinson

2009-01-01

162

Generalized hair casts due to traction.  

PubMed

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

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

2013-01-01

163

Combination Of Investment And Centrifugal Casting  

NASA Technical Reports Server (NTRS)

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.

Creeger, Gordon A.

1994-01-01

164

A Diffusing Runner for Gravity Casting  

Microsoft Academic Search

In gravity casting, the quality of an aluminum alloy casting relies on, among other things, the design of the runner system\\u000a in which the ingate velocity into the mold cavity should be controlled to stay under a critical velocity (close to 0.5 m\\/s).\\u000a In this study, a diffuser was proposed to reduce the velocity of liquid metal to below this critical

Fu-Yuan Hsu; Huey-Jiuan Lin

2009-01-01

165

Arc Casting Intermetallic Alloy (Materials Preparation Center)  

ScienceCinema

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

166

Computed Tomography For Internal Inspection Of Castings  

NASA Technical Reports Server (NTRS)

Computed tomography used to detect internal flaws in metal castings before machining and otherwise processing them into finished parts. Saves time and money otherwise wasted on machining and other processing of castings eventually rejected because of internal defects. Knowledge of internal defects gained by use of computed tomography also provides guidance for changes in foundry techniques, procedures, and equipment to minimize defects and reduce costs.

Hanna, Timothy L.

1995-01-01

167

Apollo 14 composite casting demonstration  

NASA Technical Reports Server (NTRS)

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.

1971-01-01

168

Preferential dissolution behaviour in Ni-Cr dental cast alloy  

Microsoft Academic Search

A Ni-Cr-Mo dental alloy was fabricated by three different casting methods, viz. centrifugal casting, high frequency induction\\u000a casting and vacuum pressure casting. The dependence of cast microstructure on the electrochemical corrosion behaviour was\\u000a investigated using potentiodynamic cyclic and potentiostatic polarization techniques, impedance spectroscopy and scanning\\u000a electron microscopy. The experimental results were compared and discussed with those obtained for a Co-Cr-Mo

Viswanathan S. Saji; Han Cheol Choe

2010-01-01

169

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

DOEpatents

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.

Stoddard, Nathan G. (Gettysburg, PA)

2011-11-01

170

Casting And Solidification Technology (CAST): Directional solidification phenomena in a metal model at reduced gravity  

NASA Technical Reports Server (NTRS)

The Casting and Solidification Technology (CAST) experiment will study the phenomena that occur during directional solidification of an alloy, e.g., constitutional supercooling, freckling, and dendrite coarsening. The reduced gravity environment of space will permit the individual phenomena to be examined with minimum complication from buoyancy driven flows.

Mccay, M. H.

1988-01-01

171

Effect of ring liner and casting ring temperature on the dimension of cast posts  

Microsoft Academic Search

Statement of Problem: If a post does not fit passively, binding with the radicular tooth structure occurs, possibly increasing the risk for root fracture. Therefore, it is necessary to fabricate slightly undersized cast posts to allow for passive fit and cement placement. Shrinkage of the mold cavity may be a desired effect during the casting of posts. Purpose: This study

Rafael Del Castillo; Carlo Ercoli; Gerald N. Graser; Ross H. Tallents; Mark E. Moss

2000-01-01

172

Predictable Casting for Dimensional Shrinkage of Fast-cast Post-and-cores.  

PubMed

SUMMARY Statement of problem : Prior investigations into dimensional shrinkage of fast-cast post-and-cores resulted in variable dimensions. There is a need for consistent shrinkage of cast post-and-cores to reduce or eliminate lateral stresses on the remaining tooth structure. Purpose : The purpose of this research was to find a method of casting post-and-cores that would result in consistent shrinkage. Material and Methods : A total of 45 methyl methacrylate post-and-core patterns, 10 mm long, were fabricated from a standardized steel block. Three methods were used to cast the post-and-core. Investment materials used were Fast Fire 15 (Whip Mix Corp, Louisville, KY, USA) and Beauty Cast gypsum (Whip Mix Corp). Three groups of sample post and core patterns were cast, varying the investment material used and the burnout time. Results : Results show a statistical significance between the investment materials (p<0.05). The accelerated technique produced the most consistent results, and all samples had shrinkage of the casting. Conclusions : The use of a phosphate investment with an accelerated technique can produce consistent and predictable shrinkage of cast post-and-cores. PMID:24720261

Hansen, Pa

2014-01-01

173

Predicting Pattern Tooling and Casting Dimensions for Investment Casting, Phase II.  

National Technical Information Service (NTIS)

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...

2005-01-01

174

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

National Technical Information Service (NTIS)

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...

A. S. Sabau

2005-01-01

175

Advanced Pattern Material for Investment Casting Applications  

SciTech Connect

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.

F. Douglas Neece Neil Chaudhry

2006-02-08

176

Precision Casting via Advanced Simulation and Manufacturing  

NASA Technical Reports Server (NTRS)

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.

1997-01-01

177

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

SciTech Connect

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.

Sabau, Adrian S [ORNL

2005-09-01

178

Biliary Cast Syndrome in an Opium Inhaler  

PubMed Central

Biliary cast syndrome (BCS) is an uncommon complication which is mostly described in orthotopic liver transplantation. However, BCS has also been reported rarely in non-liver transplant patients. We describe a male long-term opium inhaler with BCS who underwent successful endoscopic cast removal by balloon enteroscopy-guided endoscopic retrograde cholangiopancreatography. A 52-year-old man, who was a known case of opium addiction, presented with the chief complaint of epigastric pain for 1 week prior to admission. Routine laboratory evaluation revealed cholestatic liver enzyme elevation. A cholestatic pattern was seen in radiographic modalities. Endoscopic retrograde cholangiopancreatography showed a linear filling defect in the intra- and extrahepatic duct. A long biliary cast was successfully removed using an extractor balloon. After removal of the biliary cast the patient is receiving ursodeoxycholic acid and does not report any problem 4 months after treatment. It seems that biliary dyskinesia due to long-term opium use can be a predisposing factor for biliary cast formation.

Dabiri, Reza; Aghdae, Hamid Asadzadeh; Rajabalinia, Hasan; Mohammad Alizadeh, Amir Houshang

2013-01-01

179

Robust digital watermarking using random casting method  

NASA Astrophysics Data System (ADS)

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.

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

2001-12-01

180

A Diffusing Runner for Gravity Casting  

NASA Astrophysics Data System (ADS)

In gravity casting, the quality of an aluminum alloy casting relies on, among other things, the design of the runner system in which the ingate velocity into the mold cavity should be controlled to stay under a critical velocity (close to 0.5 m/s). In this study, a diffuser was proposed to reduce the velocity of liquid metal to below this critical value, while the flow rate remained almost unchanged. Flow separation and dead zones in the diffuser design were avoided. A computational modeling package and a real casting experiment (water analogy method) were employed for exploring and verifying the new design. The efficiency of the diffuser was quantified by the measurement of coefficient of discharge Cd. For this new diffuser, the pressure recovery coefficient C p and the loss coefficient K L were also estimated.

Hsu, Fu-Yuan; Lin, Huey-Jiuan

2009-12-01

181

A new casting defect healing technology  

SciTech Connect

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.

Hodge, E.S.; Reddoch, T.W. [ForMat Industries, Inc., Knoxville, TN (United States); Viswanathan, S. [Oak Ridge National Lab., TN (United States)

1997-01-01

182

Composites for Advanced Space Transportation Systems (CASTS)  

NASA Technical Reports Server (NTRS)

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.

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

1979-01-01

183

Broken People: Caste Violence Against India's "Untouchables"  

NSDL National Science Digital Library

Even though "the imposition of social disabilities on persons by reason of their birth in certain castes" was legally abolished under India's constitution in 1950, "untouchability" is still practiced today in much of rural India. The "untouchable" caste -- or Dalits, which literally means "broken people" -- comprises over one-sixth of India's population, or 160 million people. This 310-page report, recently issued by Human Rights Watch (HRW), documents the discrimination and violence suffered by Dalits under the societal rule of higher-caste groups in the Indian states of Bihar, Tamil Nadu, Maharashtra, Andhra Pradesh, Karnataka, and Gujarat. The report also examines the government's role in preserving the status quo by thwarting peaceful social activism and failing to abolish exploitative labor practices through appropriate legislation.

184

TiC reinforced cast chromium steels  

SciTech Connect

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 440°C 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.

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

2003-11-01

185

Modeling of casting microstructures and defects  

SciTech Connect

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.

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

1997-09-26

186

Effect of Phase Pressure on Casting Properties in Cold Chamber Die Casting Process  

NASA Astrophysics Data System (ADS)

This paper focuses on the parametric optimization of process parameter in cold chamber die casting for an industrial component (crank case). Three controllable factors of the cold chamber die casting process (namely: 1st phase pressure, 2nd phase pressure and limit switch position) were studied at three levels each by Taguchi's parametric approach and single-response optimization was conducted to identify the main factor controlling surface hardness, weight of casting and dimensional accuracy (?d). Castings were produced using aluminium alloy at recommended parameters through cold chamber die casting process. Analysis shows that in cold chamber die casting process the percentage contribution of 1st phase pressure, limit switch position and 2nd phase pressure for surface hardness is 84.17, 11.43 and 1.93 % respectively. While in the case of weight of cast component, the contribution of limit switch position is 52.26 %, followed by 1st phase pressure and 2nd phase pressure 34.77 and 9.65 % respectively. Further for ?d, contribution of 1st phase pressure is 64.55 %, limit switch position 27.71 % and 2nd phase pressure contributes 4.87 %.

Singh, R.; Kapoor, R.

2013-04-01

187

Compound cast product and method for producing a compound cast product  

DOEpatents

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).

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

2002-09-17

188

Fisher4Cast: Fisher Matrix Toolbox  

NASA Astrophysics Data System (ADS)

The Fisher4Cast suite, which requires MatLab, provides a standard, tested tool set for general Fisher Information matrix prediction and forecasting for use in both research and education. The toolbox design is robust and modular, allowing for easy additions and adaptation while keeping the user interface intuitive and easy to use. Fisher4Cast is completely general but the default is coded for cosmology. It provides parameter error forecasts for cosmological surveys providing distance, Hubble expansion and growth measurements in a general, curved FLRW background.

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

2012-01-01

189

Fluxing agent for metal cast joining  

SciTech Connect

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.

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

2002-11-05

190

Caste-Selective Pheromone Biosynthesis in Honeybees  

NASA Astrophysics Data System (ADS)

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.

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

1996-03-01

191

Feasibility of Investment Casting Preforms for Phalanx Penetrators.  

National Technical Information Service (NTIS)

The objective of this program was to demonstrate, in a preliminary fashion, that depleted uranium 2 w/o molybdenum alloy Phalanx penetrators can be produced by the investment casting process and to provide cast penetrators for ballistic evaluation. Result...

E. J. Tenerini

1977-01-01

192

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

193

Membranes for Reverse Osmosis by Direct Casting on Porous Supports.  

National Technical Information Service (NTIS)

Cellulose acetate membranes cast under a variety of conditions on various support materials were tested with a standard 1% sodium chloride at different pressures. The objective was to examine the possibility of casting thin cellulose acetate membranes on ...

R. L. Nickelson E. A. Birkhimer D. E. Coverdell J. Y. Lai D. G. Wang

1970-01-01

194

Casting machine for grids of lead storage batteries  

SciTech Connect

A machine for the casting and subsequent stamping of grids for lead storage batteries, particularly ones consisting of low-Sb and Pb-Ca alloys, has a pouring nozzle to receive and pour a predetermined amount of melt into a casting mold arranged vertically beneath it. For removal from the mold, conveyance and machining of the castings without deformation, particularly if soft alloys are used a lifter for the casting is arranged on the casting mold, by means of which lifter the casting can be brought while remaining in its vertical position onto a conveyor device which is developed as a cooling path for hardening of the casting. At the end of the path a deflection unit repositions the casting which has been transported vertically up to this point into a horizontal position and by a feed device is advanced to a stamping machine from where the grid passes onto a conveyor belt.

Sperling, F.; Hennecke, A.

1984-06-26

195

Solidification of Spheroidal and Flake-Graphite Cast Iron.  

National Technical Information Service (NTIS)

The experimental observations of the solidification of cast iron have been interpreted using modern ideas in solidification theory to explain spheroidal graphite formation. In addition to experiments with cast iron, spherulites of ice were grown in the tr...

W. Oldfield G. T. Geering W. A. Tiller

1968-01-01

196

'TUNDTEMP' - an advisory tool for the continuous steel casting process.  

National Technical Information Service (NTIS)

This report summarizes the major features of the advisory tool 'TUNDTEMP', developed to act as a decision support in the continuous steel casting process. 'TUNDTEMP' provides a means to predict abnormal phenomena of temperature origin in the casting that ...

M. Sillanpaeae

1993-01-01

197

29 CFR 452.131 - Casting of ballots; delegate elections.  

Code of Federal Regulations, 2013 CFR

... Casting of ballots; delegate elections. 452.131 Section 452.131 Labor Regulations Relating to Labor OFFICE OF... Election Procedures; Rights of Members § 452.131 Casting of ballots; delegate elections. The...

2013-07-01

198

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

199

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

200

40 CFR 464.10 - Applicability; description of the aluminum casting subcategory.  

Code of Federal Regulations, 2013 CFR

...Applicability; description of the aluminum casting subcategory. 464.10...AND CASTING POINT SOURCE CATEGORY Aluminum Casting Subcategory § 464.10 Applicability; description of the aluminum casting subcategory. The...

2013-07-01

201

40 CFR 464.20 - Applicability; description of the copper casting subcategory.  

Code of Federal Regulations, 2013 CFR

... Applicability; description of the copper casting subcategory. 464.20 Section...MOLDING AND CASTING POINT SOURCE CATEGORY Copper Casting Subcategory § 464.20 Applicability; description of the copper casting subcategory. The...

2013-07-01

202

Potential of centrifugal casting for the production of near net shape uranium parts.  

National Technical Information Service (NTIS)

This report was written to provide a detailed summary of a literature survey on the near net shape casting process of centrifugal casting. Centrifugal casting is one potential casting method which could satisfy the requirements of the LANL program titled ...

E. Robertson

1993-01-01

203

40 CFR 464.40 - Applicability; description of the zinc casting subcategory.  

Code of Federal Regulations, 2013 CFR

...false Applicability; description of the zinc casting subcategory. 464.40 Section...MOLDING AND CASTING POINT SOURCE CATEGORY Zinc Casting Subcategory § 464.40 Applicability; description of the zinc casting subcategory. The...

2013-07-01

204

Microabrasion of cast metal margins--a warning.  

PubMed

Plastic test patterns were milled to simulate casting margins and were cast in a variety of dental alloys. The cast specimens were exposed to horizontal and vertical streams of low-pressure microabrasion with 50 microm aluminum oxide particles. Post-exposure measurements show all specimens were affected by microabrasion. Dentists and laboratory technicians who use microabrasion must be aware of the potential damage to casting margins. PMID:17362424

Mansueto, Michael A; Verrett, Ronald G; Phoenix, Rodney D

2007-01-01

205

Effect of Pressure Difference on the Quality of Titanium Casting  

Microsoft Academic Search

In casting titanium using a two-compartment casting machine, Herø et al. (1993) reported that the pressure difference between the melting chamber and the mold chamber affected the soundness of the castings. This study tested the hypothesis that differences in pressure produce castings with various amounts of porosity and different mechanical properties values. Plastic dumbbell-shaped patterns were invested with an alumina-based,

I. Watanabe; J. H. Watkins; H. Nakajima; M. Atsuta; T. Okabe

1997-01-01

206

Application of TRIZ Theory in Patternless Casting Manufacturing Technique  

NASA Astrophysics Data System (ADS)

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.

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

207

Casting the Spirit: A Handmade Legacy  

Microsoft Academic Search

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 powerful representations that

Mona Rutenberg

2008-01-01

208

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...

209

Genetic load among four Andhra caste populations  

Microsoft Academic Search

The effect of inbreeding on mortality is assessed through genetic load estimates among four caste populations, the Chakali, Kummari, Mangali, and Madiga of Andhra Pradesh, India. The regression coefficient “B” is positive and statistically not significant except in the Mangali where reduced fetal wastage with increased inbreeding coefficient is noted. The B\\/A values of the majority of populations suggest that

B. V. Babu; Y. S. Kusuma; J. M. Naidu

1994-01-01

210

Templates Aid Removal Of Defects From Castings  

NASA Technical Reports Server (NTRS)

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.

Hendrickson, Robert G.

1992-01-01

211

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...

212

Die Soldering in Aluminium Die Casting.  

National Technical Information Service (NTIS)

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 us...

Q. Han E. A. Kenik S. Viswanathan

2000-01-01

213

Cast Stainless Steel Ferrite and Grain Structure  

SciTech Connect

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.

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

2012-09-01

214

DAMPING BEHAVIOUR OF CAST AND SINTERED ALUMINIUM  

Microsoft Academic Search

Estimating damping in structures made of different materials and processes still remains as one of the biggest challenges. Aluminium is one such pioneer material which is being used extensively in aerospace, automotive and the manufacturing industry. Aluminium components are mainly manufactured by traditional casting and powder metallurgy process. The main objective of this paper is to estimate the damping ratio

Abhinav Alva; Vijay Desai

215

Cast Iron With High Carbon Content  

NASA Technical Reports Server (NTRS)

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.

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

1986-01-01

216

Carburizer Effect on Cast Iron Solidification  

NASA Astrophysics Data System (ADS)

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.

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

2014-06-01

217

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...

218

Carburizer Effect on Cast Iron Solidification  

NASA Astrophysics Data System (ADS)

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.

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

2014-04-01

219

Sputtered Protective Coatings for die Casting Dies.  

National Technical Information Service (NTIS)

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 candidat...

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

1981-01-01

220

Variability of study cast assessment among orthodontists  

Microsoft Academic Search

This study examined the accuracy and reliability with standardized definitions among 30 orthodontists in assessing different aspects of malocclusion from the study casts of 10 patients. Previous studies have indicated a lack of consistency among orthodontists in describing malocclusions. The diagnostic subcategories measured in this study included maxillary and mandibular crowding, overbite, overjet, and a modified molar, premolar, and canine

Jason W. Pair; Larry Luke; Stuart White; Kathryn Atchinson; Rita Englehart; Robert Brennan

2001-01-01

221

Roll Casting of Al-25%Si  

SciTech Connect

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 {mu}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.

Haga, Toshio [Osaka Institute of Technology, Omiya Asahiku Osaka city 535-8585 (Japan); Harada, Hideto [Graduate School of Osaka Institute of Technology, Omiya Asahiku Osaka city 535-8585 (Japan); Watari, Hisaki [Gunma University, Kiryu city, 376-8515 (Japan)

2011-05-04

222

Automation in foundry\\/casting industry  

Microsoft Academic Search

In the present study, the cooling curve analysis or thermal analysis technique during solidification of ferrous and non-ferrous alloys was used. For ferrous alloy, the temperature recording equipment IEEE 488 fitted with an Interface Scanner 740 and a GPIB (General Purpose Interface Bus) programme was used to obtain a continuous record of the temperature during solidification of the casting. The

M. M. Haque; Ahmad F. Ismail

2002-01-01

223

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...

224

Slip-Cast Coating of Alumina Crucibles.  

National Technical Information Service (NTIS)

The development of a process for coating alumina crucibles with MgO protective coat in a two-step slip casting operation is described. The best milling conditions for the alumina used were set ball milling for 24 hr. MgO had to be calcined at 1200 exp 0 C...

N. A. Haroun M. A. A. El-Masry

1980-01-01

225

Squeeze Casting of Steel Weapon Components.  

National Technical Information Service (NTIS)

The project was initiated to study the feasibility of applying the squeeze casting process to produce two specific steel weapon components - the receiver base and the barrel support of the M85 weapon. Dies were designed and fabricated for both components ...

D. A. Stawarz K. M. Kulkarni K. R. Iyer R. B. Miclot

1974-01-01

226

Sensor-based assessment of cast placement and removal.  

PubMed

Appropriate pressure during the application of a cast is critical to provide adequate stabilization of fractures. Force-sensing resistors (FSR) were used to measure pressure during cast placement and removal. The data demonstrated a signature pattern of skin pressure during the different steps of cast placement and removal. This reproducible signal provides validity evidence for our model. PMID:24732518

Maag, Anne-Lise D; Laufer, Shlomi; Kwan, Calvin; Cohen, Elaine R; Lenhart, Rachel L; Stork, Natalie C; Halanski, Matthew A; Pugh, Carla M

2014-01-01

227

Complete Simulation of High Pressure Die Casting Process  

Microsoft Academic Search

The use of simulation programs saves time and reduces the costs of the casting system design. At the same time it is possible to meet stringent product quality. Simulation can make a casting system optimal: it enables the producing of sound, high-quality castings with fewer experiments. Furthermore environmental savings and economical use of materials can be achieved when the number

Matti Sirviö; Sami Vapalahti; Jukka Väinölä

228

CAST - A CERN Experiment to Search for Solar Axions  

SciTech Connect

The CAST experiment at CERN is the only running solar axion telescope. The first results obtained so far with CAST - PHASE I is presented, which compete with the best astrophysically derived limits of the axion-to-photon coupling. The ongoing PHASE II of the experiment as well as the scheduled upgrades, which improve the axion discovery potential of CAST, are discussed.

Arik, E.; Boydag, F. S.; Cetin, S. A.; Dogan, O. B.; Hikmet, I. [Dogus University, Istanbul (Turkey); Aune, S.; Dafni, T.; Ferrer-Ribas, E.; Giomataris, I. [DAPNIA, Centre d'Etudes Nucleaires de Saclay (CEA-Saclay), Gif-sur-Yvette (France); Autiero, D.; Barth, K.; Davenport, M.; Di Lella, L.; Lasseur, C.; Papaevangelou, T.; Placci, A.; Riege, H.; Stewart, L.; Walckiers, L. [European Organization for Nuclear Research (CERN), Geneve (Switzerland); Belov, A. [Institute for Nuclear Research (INR), Russian Academy of Sciences, Moscow (Russian Federation)] (and others)

2007-04-23

229

New methods and materials for molding and casting ice formations  

NASA Technical Reports Server (NTRS)

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.

Reehorst, Andrew L.; Richter, G. Paul

1987-01-01

230

Casting Titanium and Zirconium in Zircon Sand Molds.  

National Technical Information Service (NTIS)

A zircon sand molding process was developed by the Bureau of Mines for static casting small titanium or zirconium shapes. Castings with unfinished weights up to 3.5 kg (7.7 lb) were produced in an inductoslag furnace and castings up to 7 kg (15.4 lb) were...

J. L. Hoffman M. L. Transue R. A. Beall R. K. Koch

1977-01-01

231

SOME PRINCIPLES FOR PRODUCING SOUND Al7Mg ALLOY CASTINGS  

Microsoft Academic Search

Principles were developed for the production of sound horizontal ; castings of the. Al-7Mg alloy. They were developed from a study of the ; relationship that exists between the thermal gradients at the center line of the ; casting and various conditions such as the size of the casting as well as the ; location of gates, risers, and chills.

W. H. Johnson; J. G. Kura

1959-01-01

232

Clean Cast Steel Technology - Machinability and Technology Transfer  

SciTech Connect

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.

C. E. Bates; J. A. Griffin

2000-05-01

233

Some basic research for thin-wall casting technology  

Microsoft Academic Search

Vacuum suction fluidity measurements were done on aluminum alloys and cast iron to establish the relationship between fluidity and various casting parameters. A prominent effect of mold coating plus mold atmosphere was found on aluminum alloys. The effects of silicon content, inoculation and spheroidizing treatments were evaluated on cast iron. Most of the effects found were explained in terms of

Niyama Eisuke; Anzai Koichi; Funakubo Tatsuya; Hiratsuka Sadato

1997-01-01

234

Roll casting of wire inserted aluminum alloy strip  

Microsoft Academic Search

Casting of wire inserted composite strip was tried using a downward melt drag twin roll caster. Casting and insert of the wire was operated by one process. Therefore, many steps to make metal matrix composite alloy can be saved by the process of the present study. The effects of the important casting conditions, which are roll speed and nozzle slit,

T. Haga; K. Takahashi; H. Inui; H. Sakaguchi; H. Watari; S. Kumai

2007-01-01

235

The effect of hot isostatic pressing on cast aluminum  

NASA Astrophysics Data System (ADS)

Aluminum-silicon alloys are the most important commercial aluminum casting alloys, primarily because of their superior casting characteristics. This article discusses the effect of hot isostatic pressing on the mechanical properties of cast aluminum alloy A356. The effect of low-cost Densal hotisostatic pressing is also examined.

Lei, C. S. C.; Frazier, W. E.; Lee, E. W.

1997-11-01

236

49 CFR 192.275 - Cast iron pipe.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false Cast iron pipe. 192.275 Section 192.275...Other Than by Welding § 192.275 Cast iron pipe. (a) Each caulked bell and spigot joint in cast iron pipe must be sealed with mechanical...

2013-10-01

237

46 CFR 153.239 - Use of cast iron.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false Use of cast iron. 153.239 Section 153.239 Shipping COAST...Cargo Containment Systems § 153.239 Use of cast iron. (a) Cast iron used in a cargo containment system must meet the...

2013-10-01

238

United States Capitol dome: Characterization of cast and wrought materials  

Microsoft Academic Search

Restoration of the cast iron dome at the United States Capitol is needed because moisture is leaking into interior areas of the building due to corrosion damage. Microstructure, composition, and tensile properties of cast and wrought samples from the dome are discussed in this report. The cast iron skin of the dome is a ferrite–pearlite gray iron with strength consistent

C. N. McCowan; T. A. Siewert; J. D. McColskey; K. Hildebrand; D. L. Olson

2011-01-01

239

Sensor-Based Assessment of Cast Placement and Removal  

PubMed Central

Appropriate pressure during the application of a cast is critical to provide adequate stabilization of fractures. Force-sensing resistors (FSR) were used to measure pressure during cast placement and removal. The data demonstrated a signature pattern of skin pressure during the different steps of cast placement and removal. This reproducible signal provides validity evidence for our model.

MAAG, Anne-Lise D.; LAUFER, Shlomi; KWAN, Calvin; COHEN, Elaine R.; LENHART, Rachel L.; STORK, Natalie C.; HALANSKI, Matthew A.; PUGH, Carla M.

2014-01-01

240

49 CFR 192.275 - Cast iron pipe.  

Code of Federal Regulations, 2010 CFR

...2009-10-01 2009-10-01 false Cast iron pipe. 192.275 Section 192...Materials Other Than by Welding § 192.275 Cast iron pipe. (a) Each caulked bell and spigot joint in cast iron pipe must be sealed with...

2009-10-01

241

49 CFR 192.275 - Cast iron pipe.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Cast iron pipe. 192.275 Section 192...Materials Other Than by Welding § 192.275 Cast iron pipe. (a) Each caulked bell and spigot joint in cast iron pipe must be sealed with...

2010-10-01

242

Transient altitude-induced compartment syndrome associated with fiberglass casts using waterproof cast padding.  

PubMed

Changes in aircraft cabin pressure and its interplay with a fixed diameter fiberglass cylindrical cast and the closed air cells in waterproof cast padding may cause a transient altitude-induced compartment syndrome. In this case series, 2 patients reported transient compartment syndromes that resolved with aircraft decent. As proof of concept, this work displays photographic and video evidence showing the difference in air cell volume from experimental data in a vacuum chamber as well as real-world volume changes at cruise altitude in a commercial airliner. Transient altitude-induced compartment syndromes associated with fiberglass casts using waterproof cast padding are real and surgeons and patients should be advised of this potentially devastating complication. PMID:23431541

Kadzielski, John; Bae, Donald S

2013-01-01

243

Control of Cast Grain Size of Steel Castings-Effect of Structure and Nonmetallics on Properties.  

National Technical Information Service (NTIS)

The relation of dendrite structure, nonmetallics and microporosity to solidification time and refinement by inoculation was investigated and correlated to mechanical properties of AISI 4335 steel castings. The dendrite spacing is determined by solidificat...

P. F. Wieser J. F. Wallace

1967-01-01

244

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

PubMed

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

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

2011-09-01

245

A new freeze casting technique for ceramics  

NASA Astrophysics Data System (ADS)

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.

Araki, Kiyoshi

246

The effect of casting temperature on the properties of squeeze cast aluminium and zinc alloys  

Microsoft Academic Search

Gravity casting and squeeze casting were carried out on an aluminium alloy with 13.5% silicon and a zinc alloy with 4.6% aluminium with different temperatures, 660, 690 and 720°C for the former and 440, 460 and 480°C for the latter. A top-loading crucible furnace was used to melt the alloys. The die-preheat temperatures used were 200–220°C for the aluminium alloy

L. J. Yang

2003-01-01

247

Effect of niobium on the as-cast microstructure of hypereutectic high chromium cast iron  

Microsoft Academic Search

The effect of niobium element on the as-cast microstructure of the hypereutectic high chromium cast irons containing 4.0 wt.% C and 20.0 wt.% Cr was studied by means of the optical microscopy, the scanning electron microscopy, the X-ray diffraction, the energy dispersive X-ray spectrometry, the electron probe microanalyzer and the Leica image analyzer. With the addition of Nb, NbC carbides are formed

Xiaohui Zhi; Jiandong Xing; Hanguang Fu; Bing Xiao

2008-01-01

248

Effect of titanium on the as-cast microstructure of hypereutectic high chromium cast iron  

Microsoft Academic Search

The effect of titanium on the as-cast microstructure of a hypereutectic high-Cr cast iron containing 4.0 wt.% carbon and 20.0 wt.% chromium was investigated. With the increase of titanium concentration, the primary M7C3 carbides were refined and the volume fraction of all carbides (primary and eutectic carbide) was decreased gradually. TiC particles became larger and agglomerated when the titanium concentration was 1.47 wt.%.

Xiaohui Zhi; Jiandong Xing; Hanguang Fu; Yiming Gao

2008-01-01

249

Effect of cerium on the as-cast microstructure of a hypereutectic high chromium cast iron  

Microsoft Academic Search

The effect of cerium element on the as-cast microstructure of a hypereutectic high chromium cast iron (HCCI) containing 4.0 wt.% C and 20.0 wt.% Cr was studied by means of optical microscopy (OM), scanning electron microscopy (SEM) and energy dispersive X-ray spectrometry (EDS). The results indicate that the primary M7C3 carbides are refined and spheroidized with the addition of suitable amount of

Yinhu Qu; Jiandong Xing; Xiaohui Zhi; Jiyun Peng; Hanguang Fu

2008-01-01

250

The Fit of Gold-alloy Full-crown Castings Made with Ceramic Casting Ring Liners  

Microsoft Academic Search

Measurements were made of the fit of gold-alloy full-crown castings produced with dry ceramic ring liners. When used with vacuum investing, these liners absorb relatively large amounts of water from the investment mix (thereby reducing its original W\\/P ratio) and then function as wet liners, thus increasing the investment's potential expansion and giving castings which are consistently larger than when

R. Earnshaw; E. F. Morey

1992-01-01

251

Corrosion behaviour of high pressure die-cast and semi-solid cast AZ91D alloys  

Microsoft Academic Search

The microstructure and the corrosion behaviour of high pressure die-cast and semi-solid cast AZ91D magnesium alloys have been investigated. Semi-solid processing leads to a structure with large rounded grains of a solid solution of magnesium (? phase) whereas die-cast alloys are more homogeneous. Electrochemical measurements, particularly with impedance spectroscopy, have shown that the semi-solid cast alloy possesses a corrosion rate

S Mathieu; C Rapin; J Hazan; P Steinmetz

2002-01-01

252

High-pressure die casting: effect of fluid flow on the microstructure of LM24 die-casting alloy  

Microsoft Academic Search

The effect of fluid flow rate on the microstructure of LM24 high pressure die-casting alloy was studied using a fully controlled cold chamber high-pressure die-casting machine and casting a series of rectangular coupons of 65 × 130 × 4 mm. All castings showed a bimodal distribution of dendrites in which the morphology of dendrites was completely different to the classic

M. R. Ghomashchi

1995-01-01

253

Viability changes: Microbiological analysis of dental casts  

PubMed Central

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.

Zilinskas, Juozas; Junevicius, Jonas; Ramonaite, Agne; Pavilonis, Alvydas; Gleiznys, Alvydas; Sakalauskiene, Jurgina

2014-01-01

254

Viability changes: Microbiological analysis of dental casts.  

PubMed

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 and 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

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

2014-01-01

255

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

NASA Astrophysics Data System (ADS)

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 spectroscopy—EDS). 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.

Wróbel, Tomasz

2014-03-01

256

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

NASA Astrophysics Data System (ADS)

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 spectroscopy—EDS). 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.

Wróbel, Tomasz

2014-05-01

257

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

NASA Astrophysics Data System (ADS)

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.

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

2012-01-01

258

The production and evaluation of metal-matrix composite castings produced by a pressure-assisted investment casting process  

Microsoft Academic Search

A process for the production of aluminium alloy metal-matrix composites (MMCs) by the liquid metal infiltration route is presented. This process was based on investment casting to enhance its ability to cast complex shapes by the fibre preform infiltration method. Squeeze casting has been the most popular route for producing such composites due to its ability to provide high positive

C. S. Lim; A. J. Clegg

1997-01-01

259

Effect of low frequency electromagnetic field on casting crack during DC casting superhigh strength aluminum alloy ingots  

Microsoft Academic Search

Super high strength aluminum alloys are very important materials to the aerospace industries, however, cracks often occur during the DC casting process because of their high alloying element content. In this paper, a new low frequency electromagnetic casting (LFEC) process is used to study the possibility of eliminating casting cracks. The results show that a low frequency electromagnetic field eliminates

Zuo Yubo; Cui Jianzhong; Zhao Zhihao; Zhang Haitao; Qin Ke

2005-01-01

260

Method of making an apertured casting. [using duplicate mold  

NASA Technical Reports Server (NTRS)

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.

Terray, A. (inventor)

1976-01-01

261

Caste in 21st Century India: Competing Narratives  

PubMed Central

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.

Desai, Sonalde; Dubey, Amaresh

2012-01-01

262

Mold and method for making variable thickness cast articles  

SciTech Connect

A method for casting molten metal articles of variable thickness in a mold is described, said method comprising the steps of: forming cavity walls within a permanent mold to define a casting cavity; lining portions of the cavity walls with sand to conform with the size and shape of corresponding sections of the article to be cast within the cavity; forming unlined bare portions of the cavity walls to conform with the size and shape of other corresponding sections of the article; varying the thickness of the sand to form thick and thin portions of the sand liner which are reversely correlated to corresponding thin and thick sections of the resultant cast article such that the sand liner is thicker in sections where the cast article is thin and is thinner in sections where the cast article is thicker; casting molten metal into the casting cavity causing the varied thickness sections to cool at different rates with the thinner sections cooling at a relatively slower rate than the thicker sections for producing an approximately equalized cooling time for these sections of the cast article; and characterized by controlling the temperature of the bore portions of the cavity walls during casting for precisely controlling the cooling rates and resultant physical properties of the sections of the cast article in contact with the bare portions.

Ruff, G.F.; Kuhn, J.W.; Wylie, R.J.

1993-05-25

263

Biliary casts after liver transplantation: Morphology and biochemical analysis  

PubMed Central

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.

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

2013-01-01

264

Metallic Fuel Casting Development and Parameter Optimization Simulations  

SciTech Connect

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.

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

2013-03-01

265

Determination of stresses in below-knee walking casts.  

PubMed

Glass fibre bandages are now commonly used for definitive below-knee walking casts, in preference to plaster of Paris, since they are better able to withstand the stresses imposed upon them. This paper describes a technique for recording the cast strains in glass fibre bandages and shows typical stress levels in patient and volunteer casts. A typical map of the stress variations in walking casts during gait in a volunteer has been produced. The study shows that the high stresses recorded along the medial and lateral borders of the foot by the strain gauge technique are confirmed by clinical experience, since this is where failure is most commonly seen in below-knee walking casts. It is concluded that the current generation of polyurethane impregnated glass fibre splinting bandages are too brittle in many cases for below-knee walking casts and that a more flexible fabric would reduce the incidence of cast breakdown. PMID:23916106

Wytch, R; Mitchell, C G; Gaffron, I D; Neil, G; Wardlaw, D

1990-02-01

266

Die Casting Part Distortion: Prediction and Attenuation  

SciTech Connect

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.

Dr, R. Allen Miller

2002-02-12

267

Volatile species retention during metallic fuel casting  

NASA Astrophysics Data System (ADS)

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.

Fielding, Randall S.; Porter, Douglas L.

2013-10-01

268

The USAMP magnesium powertrain cast components project  

NASA Astrophysics Data System (ADS)

Despite the demonstrated ability of magnesium alloys to significantly reduce weight at acceptable costs in many areas of an automobile, powertrain components have not benefited from this metal, primarily because the high-temperature alloys that are required for engines and transmissions are too expensive. However, the U.S. Department of Energy and the U.S. Automotive Materials Partnership have launched a project to evaluate several new, potentially low-cost magnesium alloys, design several pre-competitive power-train components for the best alloy properties, cast and dynamometer or vehicle test the components in assembled powertrains, develop a powertrain magnesium alloy design database and common alloy specification, and identify andpromote the funding of fundamental research into improved magnesium alloys and casting processes.

Powell, Bob R.

2002-02-01

269

Process for slip casting textured tubular structures  

DOEpatents

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.

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

2002-01-01

270

Efficient Runner Networks for Investment Castings  

SciTech Connect

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.

GIVLER,RICHARD C.; SAYLORS,DAVID B.

2000-07-18

271

Friction Stir Welding of Magnesium Die Castings  

Microsoft Academic Search

Friction stir welding (FSW), being a solid-state process, is an attractive method for joining magnesium die castings. In this study, FSW of AZ91D and AM50A plates was performed both on the individual alloys and to join them together. The welds were sound and free from defects, except for small surface cracks in AM50A; a fine microstructure characterized the weld zones.

Jan Ivar Skar; Haavard Gjestland; Ljiljana Djapic Oosterkamp; Darryl L. Albright

272

Hardenability of steels for precision castings  

Microsoft Academic Search

1.The standard medium-carbon steel 45L, widely used for manufacturing cast machine parts, which can be melted in high-frequency induction furnaces with an acid lining, has a high hardenability and tendency to grain growth.2.Steel 50PPL, which can be melted in high-frequency induction furnaces with a basic lining, has a minimal hardenability. The ideal critical diameter of basic 50PPL is 8.6 mm,

K. Z. Shepelyakovskii; Yu. Ya. Postnikov; V. D. Kal'ner; L. S. Danil'chenko

1971-01-01

273

Solidifying Cast Iron in Low Gravity  

NASA Technical Reports Server (NTRS)

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.

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

1986-01-01

274

Mold For Casting Radius-Inspection Specimens  

NASA Technical Reports Server (NTRS)

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.

Ball, Robert N.

1988-01-01

275

Review: aqueous tape casting of ceramic powders  

Microsoft Academic Search

Slurry formulations and processing parameters of the water-based tape casting of ceramic powders are reviewed. Additives include binders, like cellulose ethers, vinyl or acrylic-type polymers; plasticizers, like glycols; and dispersants, like ammonium salts of poly(acrylic acids). Mostly alumina powders have been employed. Hydrophobing of ceramic powders permits the aqueous processing even of water-reactive powders, like aluminium nitride. Non-toxicity and non-inflammability

D. Hotza; P. Greil

1995-01-01

276

Thin sheet casting with electromagnetic pressurization  

DOEpatents

An apparatus, method and system for the casting of thin strips or strips of metal upon a moving chill block that includes an electromagnet located so that molten metal poured from a reservoir onto the chill block passes into the magnetic field produced by the electromagnet. The electromagnet produces a force on the molten metal on said chill block in the direction toward said chill block in order to enhance thermal contact between the molten metal and the chill block.

Walk, Steven R. (Winterport, ME); Slepian, R. Michael (Pittsburgh, PA); Nathenson, Richard D. (Pittsburgh, PA); Williams, Robert S. (Fairfield, OH)

1991-01-01

277

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

NASA Astrophysics Data System (ADS)

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.

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

2004-06-01

278

Thin section casting program: Volume 4, Static cast product bending, straightening, and rolling: Final report  

SciTech Connect

Statically cast 1/2'', 3/4'', and 1'' thick steel slabs were subjected to hot rolling in a laboratory reversing mill and to simulated coiling-uncoiling on a three-point bender-unbender. Tensile properties and microstructures of hot bands thinner than 0.15'' produced from the statically cast slabs were found to be independent of initial slab thickness and similar to those from conventionally cast 8''-10'' thick slabs. Cold rolled and batch annealed product from the statically cast slabs had mechanical properties equivalent to those of conventionally processed deep-drawing quality steel. Overall, the results of this task indicated that 1/2''-1'' thick steel sections produced in a twin belt caster can be coiled and uncoiled in a hot coiler box downstream of the caster without generating any cracks in the product, and that the total range of hot and cold rolled sheet and strip products with qualities equivalent to those of conventionally produced can be obtained from the 1/2''-1'' thick sections. This report is the fifth of a six volume set on thin section casting.

Not Available

1989-01-01

279

Seal welded cast iron nuclear waste container  

DOEpatents

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.

Filippi, Arthur M. (Pittsburgh, PA); Sprecace, Richard P. (Murrysville, PA)

1987-01-01

280

CAST: An Inspiring Axion Helioscope ala Sikivie  

SciTech Connect

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.

Zioutas, K.; Anastassopoulos, V. [University of Patras, Patras (Greece); Tsagri, M. [University of Patras, Patras (Greece); CERN, 1211 Geneve 23 (Switzerland); Semertzidis, Y. [Brookhaven National Laboratory, Upton, NY (United States); Papaevangelou, T. [IRFU, Centre d'Etudes Nucleaires de Saclay, Gif-sur-Yvette (France)

2010-08-30

281

Fisher Matrix Preloaded — FISHER4CAST  

NASA Astrophysics Data System (ADS)

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.

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

282

Microporosity prediction in aluminum alloy castings  

NASA Astrophysics Data System (ADS)

A comprehensive methodology that takes into account solidification, shrinkage-driven interdendritic fluid flow, hydrogen precipitation, and porosity evolution has been developed for the prediction of the microporosity fraction and distribution in aluminum alloy castings. The approach may be used to determine the extent of gas and shrinkage porosity, i.e., the resultant microporosity which occurs due to gas precipitation and that which occurs when solidification shrinkage cannot be compensated for by the interdendritic fluid flow. A solution algorithm in which the local pressure and microporosity are coupled is presented, and details of the implementation methodology are provided. The models are implemented in a computational framework consistent with that of commonly used algorithms for fluid dynamics, allowing a straightforward incorporation into existing commercial software. The results show that the effect of microporosity on the interdendritic fluid flow cannot be neglected. The predictions of porosity profiles are validated by comparison with independent experimental measurements by other researchers on aluminum A356 alloy test castings designed to capture a variety of solidification conditions. The numerical results reproduce the characteristic microporosity profiles observed in the experimental results and also agree quantitatively with the experimentally measured porosity levels. The approach provides an enhanced capability for the design of structural castings.

Sabau, A. S.; Viswanathan, S.

2002-04-01

283

Centrifugal Casting Features/Metallurgical Characterization of Aluminum Alloys  

NASA Astrophysics Data System (ADS)

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).

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

2008-02-01

284

Centrifugal Casting Features/Metallurgical Characterization of Aluminum Alloys  

SciTech Connect

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)

Chirita, G.; Soares, D.; Cruz, D.; Silva, F. S. [Mechanical Engineering Department, School of Engineering, Minho University (Portugal); Stefanescu, I. [Faculty of Mechanical Engineering, Dunarea de Jos University Galati (Romania)

2008-02-15

285

Anisotropic shrinkage characteristics of tape cast alumina  

NASA Astrophysics Data System (ADS)

Dimensional control during sintering is a major issue in ceramics processing to avoid high post-sintering costs associated with machining of the fired ceramic part to desired tolerances and dimensions. Ceramic forming processes such as tape casting, injection molding, and extrusion involve shear of anisotropic particles resulting in preferential alignment of the particles in the green body. This preferential alignment causes directionality in mechanical, electrical, optical, and magnetic properties and most importantly warpage or distortion during sintering. A large effort has been devoted to synthesizing ceramic green bodies with minimal density gradients and uniform packing and modeling the sintering behavior evolution but little effort has been devoted to characterizing orientation of particles and the effect of preferential alignment on sintering shrinkage anisotropy. A systematic study was initiated to study the effect of processing variables such as shear rate, solids loading, temperature, and binder content on aqueous tape cast alumina. Three different alumina systems: A16-SG, Baikowski RC-UFX DBM and RC-LS DBM were investigated. Aqueous tapes of high solids loading alumina (56 vol. %) were tape cast at various speeds and thicknesses and assuming plane Couette flow a shear rate regime of 21--270 s-1 was investigated. Higher shear rates and high solids loading resulted in higher in-plane anisotropy whereas the anisotropy in the thickness direction was higher for low solids loading systems. The anisotropy was found to be fairly constant above a certain critical shear rate (˜100 s-1) irrespective of the temperature and the solids loading and this correlated with the viscosity-shear rate relationship of the cast slips. The higher shrinkage anisotropy in the thickness direction for the low solids loading systems (35 and 45 vol. %) was attributed to the higher amount of organics in the slip required to sustain the suitable viscosity for tape casting and subsequently the strains associated with binder removal. The sintering rate in the thickness direction was significantly higher. This was attributed to more number of necks resulting from platy nature of alumina particles and the strains associated with binder removal. SEM images in the thickness direction after intermediate levels of sintering clearly revealed that the particles become more isotropic much earlier as compared to the in-plane direction. (Abstract shortened by UMI.)

Patwardhan, Jaideep Suresh

286

Cast Stone Formulation At Higher Sodium Concentrations  

SciTech Connect

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

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

2013-09-17

287

Cast Stone Formulation At Higher Sodium Concentrations  

SciTech Connect

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

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

2013-10-02

288

Tensile properties of as-cast iron-aluminide alloys  

SciTech Connect

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.

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

1995-01-01

289

Practice of overburden casting at the Trapper Mine - Craig, Colorado  

SciTech Connect

Enfield Pit was chosen to test overburden casting at the Trapper Mine in Colorado. Seam and overburden geology, and drilling and blasting patterns are described. Tables summarize the costs involved in cast blasting. The primary problem encountered was coal losses along the open face due to high powder factors and heave of the overburden. It was concluded that cast blasting has the potential of considerable savings in overburden stripping. 3 figures, 2 tables.

Dupree, P.D.

1984-01-01

290

Radiographic evaluation of porosities in removable partial denture castings.  

PubMed

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

Lewis, A J

1978-03-01

291

Aqueous suspensions for tape-casting based on acrylic binders  

Microsoft Academic Search

The use of water-based systems represents an interesting alternative to the widespread non-aqueous tape-casting but the low strength of water-based binders generally limits their applicability. A tape-casting slurry is a complex system where each organic component has a substantial effect on the rheological behaviour. In this study the effect of the dispersant and binders in alumina aqueous tape-casting slurries were

C. Pagnoux; T. Chartier; M. de F. Granja; F. Doreau; J. M. Ferreira; J. F. Baumard

1998-01-01

292

Failure Analysis of Cast Lead–Antimony Battery Grids  

Microsoft Academic Search

This paper presents the failure investigation of lead-acid battery grids received from a local battery manufacturer. Distortion,\\u000a cracking, and brittleness were observed in as-cast grids. These battery grids were gravity cast by re-melting of locally made\\u000a Pb–Sb ingots. However, similar distortion and brittleness were not observed in grids of similar design cast by re-melting\\u000a of imported Pb–Sb ingots. Spectroscopy, optical

Fawad TariqS; S. Umair Azher; Nausheen Naz

2010-01-01

293

Erosive wear characteristics of spheroidal carbides cast iron  

Microsoft Academic Search

In the present investigation, the authors reported erosive wear property of spheroidal carbides cast irons (SCI). SCI was obtained at the temperature of 1700–1800°C by adding about 10% vanadium to crystallize vanadium spheroidal carbides in the structure. Erosive wear tests were performed on high manganese cast iron with spheroidal carbides (SCI–VMn), high V–Cr–Ni cast iron with spheroidal carbides (SCI–VCrNi) and

Xinba Yaer; Kazumichi Shimizu; Hideto Matsumoto; Tadashi Kitsudo; Tadashi Momono

2008-01-01

294

Depth of oscillation marks forming in continuous casting of steel  

Microsoft Academic Search

The surface of continuously cast slabs is characterized by the presence of oscillation marks. Direct linkage of the continuous\\u000a casting process and hot rolling process requires that cast slabs should be free of surface defects. In the present work, a\\u000a mechanical model has been developed for the prediction of the depth of oscillation marks of the depression type. It is

Klaus Schwerdtfeger; Hong Sha

2000-01-01

295

Modeling of asymmetric membrane formation by dry-casting method  

Microsoft Academic Search

Many polymeric membranes are produced by phase inversion technique invented by Loeb and Sourirajan in 1962. The dry-casting method is one of the major phase inversion techniques in which a homogeneous polymer solution consisting of solvent(s) and nonsolvent(s) is cast on a support and then evaporation of the casting solution takes place under convective conditions. In this paper, we model

Sacide Alsoy Altinkaya; Bulent Ozbas

2004-01-01

296

Site pre-cast yard layout arrangement through genetic algorithms  

Microsoft Academic Search

The use of modular construction has gained wide acceptance in the housing sector. Standardized modular units are often pre-cast on site. The establishment of site pre-cast yard, in particular arranging the pre-cast facilities within the compound, presents real challenge to site management. This complex task is further aggregated with the involvement of several resources with different transport cost. A GA-model

Sai-On Cheung; Thomas Kin-Lun Tong; Chi-Ming Tam

2002-01-01

297

Features of phase transformations in high-chromium cast irons  

Microsoft Academic Search

1.In contrast to cast irons with 12–14% Cr, in cast irons with 29–30% Cr transformation by bainitic and martensitic mechanisms is prevalent.2.With increasing content of carbon and manganese there is an increase in austenite stability in both the pearlitic and intermediate regions.3.From hardenability diagrams plotted it is possible to select cast iron compositions providing maximum hardness in a given cross

E. V. Rozhkova; S. S. Mikhailovskaya; I. I. Tsypin

1983-01-01

298

Low-pressure die casting of magnesium alloy AM50: Response to process parameters  

Microsoft Academic Search

Low-pressure die casting (LPDC) process has been successfully used to produce sound magnesium alloy AM50 castings. The influence of process parameters: filling time, pressure holding time, die temperature, holding pressure and casting temperature, on the mechanical properties, microstructure and density of LPDC castings were studied. The optimal process parameters for LPDC casting have been experimentally determined as follows: filling time

Penghuai Fu; Alan A. Luo; Haiyan Jiang; Liming Peng; Yandong Yu; Chunquan Zhai; Anil K. Sachdev

2008-01-01

299

Experimental study on the ice pattern fabrication for the investment casting by rapid freeze prototyping (RFP)  

Microsoft Academic Search

The process of investment casting has come to occupy a key position in the range of modern metal casting techniques. Wax pattern is widely used in the investment casting. However, there exist some problems and technical difficulties in using it such as wax pattern expanding, ceramic shell cracking, etc. A new investment casting technology, named freeze cast process (FCP), has

Qingbin Liu; Guanghua Sui; M. C. Leu

2002-01-01

300

Wettability of elastomeric impression materials and voids in gypsum casts.  

PubMed

Numerous factors are involved in making an accurate void-free dental artificial stone cast or die. The relationship of the wettability of an elastomeric impression material and its interaction with the gypsum slurry is an important factor. This study examined the relative "pourability" of several impression materials by counting the number of resultant voids in artificial stone casts containing 48 point angles. Those elastomers that exhibited the lowest contact angle with water produced artificial stone casts with the fewest voids. Surfactants applied to the impression material significantly reduced the number of voids in artificial stone casts, as did modified elastomers designated by the manufacturer as hydrophilic. PMID:1774689

Cullen, D R; Mikesell, J W; Sandrik, J L

1991-08-01

301

Short arm plaster cast for distal pediatric forearm fractures.  

PubMed

Ten years' clinical experience with below-elbow plaster cast treatment of distal one third pediatric forearm fractures was subjected to an independent retrospective radiographic review. In the study population of 761 fractures, no significant displacement occurred while the forearm remained in plaster. The average angulation change was 4.5 degrees (SD +/- 2.2 degrees). In each angulation change > 5 degrees, poor cast molding was evident, as reflected by a high "cast index" (p < 0.01). Although this technique is technically demanding, excellent results are obtained in all distal pediatric forearm fractures if proper cast molding is used. PMID:8188836

Chess, D G; Hyndman, J C; Leahey, J L; Brown, D C; Sinclair, A M

1994-01-01

302

Casting materials and their application in research and teaching.  

PubMed

From a biological point of view, casting refers to filling of anatomical and/or pathological spaces with extraneous material that reproduces a three-dimensional replica of the space. Casting may be accompanied by additional procedures such as corrosion, in which the soft tissue is digested out, leaving a clean cast, or the material may be mixed with radiopaque substances to allow x-ray photography or micro computed topography (µCT) scanning. Alternatively, clearing of the surrounding soft tissue increases transparency and allows visualization of the casted cavities. Combination of casting with tissue fixation allows anatomical dissection and didactic surgical procedures on the tissue. Casting materials fall into three categories namely, aqueous substances (India ink, Prussian blue ink), pliable materials (gelatins, latex, and silicone rubber), or hard materials (methyl methacrylates, polyurethanes, polyesters, and epoxy resins). Casting has proved invaluable in both teaching and research and many phenomenal biological processes have been discovered through casting. The choice of a particular material depends inter alia on the targeted use and the intended subsequent investigative procedures, such as dissection, microscopy, or µCT. The casting material needs to be pliable where anatomical and surgical manipulations are intended, and capillary-passable for ultrastructural investigations. PMID:24564951

Haenssgen, Kati; Makanya, Andrew N; Djonov, Valentin

2014-04-01

303

Advanced precision expendable pattern casting technology. 1994 Summary report  

SciTech Connect

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.

NONE

1995-05-01

304

Spray casting of steel strip: Process analysis  

NASA Astrophysics Data System (ADS)

Near-net shape manufacturing (NNSM) of thin steel sections by spray casting eliminates casting as a separate step with attendant improved microstructures and properties and significant energy savings. The process involves atomization of a stream of liquid metal and deposition of droplets in the generated spray on a moving substrate at mass flow rates of 0.25 to 2.5 kg/s. In this paper, NNSM of steel strip by the Osprey spray casting process is investigated by combining numerical simulation and experiments. Critical input parameters for the computation are quantified utilizing existing state-of-the-art mathematical models and specific experiments. Numerical computation of the consolidation of the spray at the substrate during manufacture of thin sections is conducted using both continuum and discrete event (“splat solidification”) approaches to predict: (1) variation of strip thickness in the transverse dimension and (2) isotherms and cooling rates across the strip thickness. Predicted geometries of the strip simulated by the continuum model are in good agreement with measurements. Predicted isotherms in narrow strip by the continuum approach are in reasonable agreement with thermocouple measurements for intermediate thicknesses (2 to 5 mm), and the observed microstructure is consistent with predicted cooling rates. The discrete event model predicts significantly higher cooling rates than the continuum model in the basal portion of the strip. This is consistent with the observed grain size in thin strip (

Annavarapu, Suresh; Apelian, Diran; Lawley, Alan

1990-12-01

305

Indications and limitations of splints and casts.  

PubMed

Long bone fractures are relatively common in cattle, whether they result from a self-inflicted trauma or from external actors (herd mate or farm machinery). Various advanced orthopedic techniques have been described to stabilize and treat fractures in cattle with success. Unfortunately the use of most of those techniques remains unrealistic in a field setting, rendering the realization of splints and casts still accurate for the treatment of long bone fracture in cattle. This article refers to the use of all external coaptation and their specific indications as well as their limitations. PMID:24534659

Mulon, Pierre-Yves; Desrochers, André

2014-03-01

306

Method and apparatus for strip casting  

DOEpatents

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.

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

1991-11-12

307

Method and apparatus for strip casting  

DOEpatents

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.

Follstaedt, Donald W. (Middletown, OH); Powell, John C. (Pittsburgh, PA); Sussman, Richard C. (West Chester, OH); Williams, Robert S. (Fairfield, OH)

1991-01-01

308

Continuation of Crosscutting Technology Development at Cast  

SciTech Connect

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.

Yoon, Roe-Hoan

2012-03-31

309

Uranium casting furnace automatic temperature control development  

SciTech Connect

Development of an automatic molten uranium temperature control system for use on batch-type induction casting furnaces is described. Implementation of a two-color optical pyrometer, development of an optical scanner for the pyrometer, determination of furnace thermal dynamics, and design of control systems are addressed. The optical scanning system is shown to greatly improve pyrometer measurement repeatability, particularly where heavy floating slag accumulations cause surface temperature gradients. Thermal dynamics of the furnaces were determined by applying least-squares system identification techniques to actual production data. A unity feedback control system utilizing a proportional-integral-derivative compensator is designed by using frequency-domain techniques. 14 refs.

Lind, R.F.

1992-05-31

310

Electromagnetic continuous casting project: Final report  

SciTech Connect

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.

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

311

Sputtered protective coatings for die casting dies  

NASA Technical Reports Server (NTRS)

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.

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

1981-01-01

312

Phase Transformations in Cast Duplex Stainless Steels  

SciTech Connect

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.

Yoon-Jun Kim

2004-12-19

313

Reconciling the CAST and PVLAS results.  

PubMed

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

Mohapatra, R N; Nasri, Salah

2007-02-01

314

Phase transformations in cast duplex stainless steels  

NASA Astrophysics Data System (ADS)

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.

Kim, Yoon-Jun

315

Optimal cooling strategies in continuous casting of steel with variable casting speed  

Microsoft Academic Search

In the “soft-reduction” zone of a continuous casting machine, the strand thickness is reduced slightly by compression to minimize center segregation which would decrease the steel quality. In order to successfully apply this technology, one has to ensure that final solidification takes place within the soft-reduction zone. This can be done by controlling solidification with cooling water sprayed onto the

Wilhelm Grever; Andreas Binder; Heinz W. Engl; Karl Mörwald

1996-01-01

316

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

NASA Astrophysics Data System (ADS)

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.

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

1993-08-01

317

Fabrication of high chromium cast iron\\/low carbon steel composite material by cast and hot rolling process  

Microsoft Academic Search

A sandwich-structured composite blank containing a high chromium cast iron (HCCI) and low carbon steel (LCS) claddings was successfully fabricated by casting and hot rolling, and then a series of quenching and tempering treatments were employed. The evolution of microstructures and microhardness of as-cast, hot-rolled and heat-treated specimens were investigated. The microstructures of hot-rolled HCCI are refined and significant variations

Guoliang Xie; Hui Sheng; Jingtao Han; Jing Liu

2010-01-01

318

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

SciTech Connect

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.

NONE

1997-06-01

319

Effect of Casting Conditions and Composition on Microstructural Gradients in Roll Cast Aluminum Alloys  

SciTech Connect

Twin Roll Casting (TRC) is a process by which thin strip is produced directly from molten metal. This process has many advantages over traditional Direct Chill (DC) casting where metal is cast into large slabs or ingots and subsequently hot and cold rolled into strips. While the DC casting involves large capital investment and energy consumption, TRC produces strip with thickness in the range of 10 mm to 2.5 mm in one operation without hot rolling, with less cost, energy usage and equipment requirements. In TRC AA3105, high solidification and post-solidification cooling rates lead to high manganese supersaturation throughout the as-cast strip and very fine constituent particles near strip surface. After 90% cold rolling, the TRC material shows sluggish recrystallization kinetics and a very coarse grain structure, due to concurrent forming dispersoids and/or fine constituent particles. These particles interfere with the nucleation process by preventing migration of the boundaries associated with potential nuclei, resulting in fewer recrystallization nuclei and slower nucleation rate. In addition, the fine particles can impede grain growth by exerting a pinning pressure on moving boundaries. The current study investigated the microstructure evolution in TRC AA3105 during different thermo-mechanical treatments. A systematic study of the effects of different homogenization treatments on second phase particles was carried out. The heating rate effect on recrystallization was studies using an infrared heating furnace. The effect of second phase particles on recrystallization behavior was summarized and experimental results were presented. It was shown that a desirable, fine recrystallized grain size could be obtained by either of two means- rapid heating rate ot the annealing tempeature, or by a pre-cold work homogenization heat treatment.

Burton R. Patterson

2008-05-02

320

Effect of flask vibration time on casting integrity, Surface Penetration and Coating Inclusion in lost foam casting of Al-Si Alloy  

Microsoft Academic Search

The paper presents the result of an experimental investigation conducted on medium aluminum silicon alloy casting- LM6, using no-vacuum assisted lost foam casting process. The study is directed for establishing the relationship between the flask vibrations times developed for molded sample on the casting integrity, surface penetration and coating inclusion defects of the casting. Four different flask vibration times namely

Majid Karimian; M. H. Idris; A. Ourdjini; Kali Muthu

2011-01-01

321

Aluminum Alloy and Article Cast Therefrom  

NASA Technical Reports Server (NTRS)

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.

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

2003-01-01

322

Advanced Lost Foam Casting Technology - Phase V  

SciTech Connect

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.

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

2004-04-29

323

Software Computes Tape-Casting Parameters  

NASA Technical Reports Server (NTRS)

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.

deGroh, Henry C., III

2003-01-01

324

Electrochemical etching of titanium-alloy castings  

SciTech Connect

This study was conducted to determine whether a potentiostatic electrochemical method could be used to etch selectively either the dendrites or the interdendritic material from Ti cast structures and thereby reveal their microstructures. Cast binary titanium alloys containing Mo, Ta, Nb, Al, and Cr and one multicomponent alloy containing Al, Ta, Nb, and Mo were polarized in sulfuric, oxalic, and fluosilicic acids and in a potassium hydroxide solution. Potentiostatic anodic polarization curves were obtained for each alloy. Results showed that the electrode potential for passivation was nearly the same for all alloys in a given acid, although the current density at the passivation potential varied from alloy to alloy. Generally for most alloying elements, the current density at the passivation potential decreased as the concentration of the alloying element increased, but not linearly. In the alkaline solution only the Ti-15% Cr alloy underwent significant dissolution, which occurred in the transpassive potential region. We were able to develop the dendritic structure with only the Ti-15% Mo, Ti-15% Ta, and Ti-15% Cr alloys. Possible reasons for our inability to delineate the dendritic structure in other alloys are discussed.

Griess, J.C.; David, S.A.; Gray, R.J.; Houck, C.W.

1983-10-01

325

Inoculated Slightly Hypereutectic Gray Cast Irons  

NASA Astrophysics Data System (ADS)

The current experimental investigation in this article was designed to characterize the structure of mold (M) and ladle (L) inoculated, low-S (0.025 wt.% S), low-Al (0.003 wt.% Al), slightly hypereutectic (CE = 4.4-4.5 wt.%) electric melted gray irons, typical for high performance thin-wall castings. It describes the effect of a Ca, Al, Zr-FeSi inoculant addition of 0-0.25 wt.% on structure characteristics, and compares to similar treatments with hypoeutectic irons (3.5-3.6 wt.% CE, 0.025 wt.% S, and 0.003 wt.% Al). A complex structure including primary graphite, austenite dendrites, and eutectic cells is obtained in hypereutectic irons, as the result of nonequilibrium solidification following the concept of a coexisting region. Dendrites appear to be distributed between eutectic cells at higher eutectic undercooling, while in inoculated irons and for lower undercooling, the eutectic cells are "reinforced" by eutectic austenite dendrites. A Zr, Ca, Al-FeSi alloy appears to be an effective inoculant in low S, low Al, gray cast irons, especially for a late inoculation technique, with beneficial effects on both graphite and austenite phases. First, inoculation influenced the nucleation of graphite/eutectic cell, and then their characteristics. A further role of these active elements directly contributed to form nucleation sites for austenite, as complex (Mn,X)S particles.

Chisamera, Mihai; Riposan, Iulian; Stan, Stelian; Militaru, Cristina; Anton, Irina; Barstow, Michael

2012-03-01

326

Material accountancy for metallic fuel pin casting  

SciTech Connect

The operation of the Fuel Conditioning Facility (FCF) is based on the electrometallurgical processing of spent metallic reactor fuel. The pin casting operation, although only one of several operations in FCF, was the first to be on-line. As such, it has served to demonstrate the material accountancy system in many of its facets. This paper details, for the operation of the pin casting process with depleted uranium, the interaction between the mass tracking system (MTG) and some of the ancillary computer codes which generate pertinent information for operations and material accountancy. It is necessary to distinguish between two types of material balance calculations -- closeout for operations and material accountancy for safeguards. The two have much in common, for example, the mass tracking system database and the calculation of an inventory difference, but, in general, are not congruent with regard to balance period and balance spatial domain. Moreover, the objective, assessment, and reporting requirements of the calculated inventory difference are very different in the two cases.

Bucher, R.G.; Orechwa, Y.; Beitel, J.C.

1995-08-01

327

Marketing and Technology Enhancement Project for the Domestic Die Casting Industry.  

National Technical Information Service (NTIS)

The domestic die casting industry was experiencing strong competition from overseas suppliers due to increasing imports of end-use products (which incorporated die cast components produced offshore) and purchases of offshore produced die castings by U.S. ...

1989-01-01

328

75 FR 23295 - Iron Construction Castings From Brazil, Canada, and China  

Federal Register 2010, 2011, 2012, 2013

...and 265 (Third Review)] Iron Construction Castings From Brazil, Canada...duty order on ``heavy'' iron construction castings from Brazil, the antidumping...duty order on ``heavy'' iron construction castings from Canada, and...

2010-05-03

329

Nippon Kokan Technical Report No. 36, December 1982: Overseas Continuous Casting Special Issue.  

National Technical Information Service (NTIS)

Contents: The development of slab casters; Study on the solidification phenomena in continuous casting mold; Fundamental research on solidification involved in continuous casting of steel; Production of super clean steel by slab continuous casting process...

1982-01-01

330

40 CFR 420.60 - Applicability; description of the continuous casting subcategory.  

Code of Federal Regulations, 2013 CFR

...Applicability; description of the continuous casting subcategory. 420.60 ...MANUFACTURING POINT SOURCE CATEGORY Continuous Casting Subcategory § 420.60 Applicability; description of the continuous casting subcategory. The...

2013-07-01

331

Benefits of Increased Use of Continuous Casting by the U.S. Steel Industry.  

National Technical Information Service (NTIS)

The memorandum first describes continuous casting, contrasting it with the older ingot casting process. The memorandum then explains the advantages of the continuous casting process, contrasts the rate of adoption of this technology in the U.S. steel indu...

1979-01-01

332

40 CFR 721.10667 - Slimes and sludges, aluminum and iron casting, wastewater treatment, solid waste.  

Code of Federal Regulations, 2013 CFR

...false Slimes and sludges, aluminum and iron casting, wastewater treatment, solid...10667 Slimes and sludges, aluminum and iron casting, wastewater treatment, solid...generically as slimes and sludges, aluminum and iron casting, wastewater treatment,...

2013-07-01

333

75 FR 49945 - Iron Construction Castings From Brazil, Canada, and China  

Federal Register 2010, 2011, 2012, 2013

...Iron Construction Castings From Brazil, Canada, and China AGENCY: United States International...iron construction castings from Brazil, Canada, and China...iron construction castings from Brazil, Canada, and China would likely lead to...

2010-08-16

334

76 FR 27668 - Algonac Cast Products, Inc., Algonac, MI; Notice of Revised Determination on Reconsideration  

Federal Register 2010, 2011, 2012, 2013

...Administration [TA-W-74,549] Algonac Cast Products, Inc., Algonac, MI; Notice...the workers and former workers of Algonac Cast Products, Inc., Algonac, Michigan...sales/production declines at Algonac Cast Products, Inc., Algonac,...

2011-05-12

335

21 CFR 888.5980 - Manual cast application and removal instrument.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Manual cast application and removal instrument...Surgical Devices § 888.5980 Manual cast application and removal instrument. (a) Identification. A manual cast application and removal...

2010-04-01

336

Vacuum assisted high pressure die casting of aluminium alloys  

Microsoft Academic Search

High pressure die castings usually contain gas porosity due mainly to the entrapment of air or gas in the melt during the very high speed injection of the molten metal into the cavity. In this paper, the advantages of using an evacuated die cavity during mould filling were evaluated. ASTM standard die casting tensile specimens of three Al alloys, Al–5%Si,

X. P. Niu; B. H. Hu; I. Pinwill; H. Li

2000-01-01

337

Integrated optimization system for high pressure die casting processes  

Microsoft Academic Search

High pressure die casting (HPDC) is a versatile process for producing engineered metal parts by forcing molten metal under high pressure into reusable steel dies. However there are a large number of attributes involved which contribute to the complexity of the process. A novel integrated approach is developed to optimize the high pressure die casting processes. The die temperature profiles

L. X. Kong; F. H. She; W. M. Gao; S. Nahavandi; P. D. Hodgson

2008-01-01

338

VIEW OF HARRIS BALER FROM ROOF OF CASTING AND METALS ...  

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

VIEW OF HARRIS BALER FROM ROOF OF CASTING AND METALS STORAGE OFFICE, LOOKING TOWARD CAST SHOP, THIS MACHINE WAS INSTALLED C. 1975. ITS CREW INCLUDES AN OPERATOR, A HELPER AND A JITNEY DRIVER. - American Brass Foundry, 70 Sayre Street, Buffalo, Erie County, NY

339

My shadow, myself: Cast-body shadows are embodied.  

PubMed

Objects that serve as extensions of the body can produce a sensation of embodiment, feeling as if they are a part of us. We investigated the characteristics that drive an object's embodiment, examining whether cast-body shadows, a purely visual stimulus, are embodied. Tools are represented as an extension of the body when they enable observers to interact with distant targets, perceptually distorting space. We examined whether perceptual distortion would also result from exposure to cast-body shadows in two separate distance estimation perceptual matching tasks. If observers represent cast-body shadows as extensions of their bodies, then when these shadows extend toward a target, it should appear closer than when no shadow is present (Experiment 1). This effect should not occur when a non-cast-body shadow is cast toward a target (Experiment 2). We found perceptual distortions in both cast-body shadow and tool-use conditions, but not in our non-cast-body shadow condition. These results suggest that, although cast-body shadows do not enable interaction with objects or provide direct tactile feedback, observers nonetheless represent their shadows as if they were a part of them. PMID:24243137

Kuylen, Christopher; Balas, Benjamin; Thomas, Laura E

2014-06-01

340

Measuring cast iron graphite size by ultrasonic attenuation  

Microsoft Academic Search

Precipitated graphite geometry is one of the main microstructural parameters that contribute to cast iron mechanical properties. In this paper we address the measurement of the graphite size by ultrasonic attenuation. Samples of different cast iron microstructures were characterized by quantitative metallographic techniques and further correlated with ultrasonic parameters. Longitudinal ultrasonic waves were generated and detected by commercial broadband piezoelectric

S. E. Kruger; J. M. A. Rebello; J. Charlier

2002-01-01

341

Castes, Migration, Immunogenetics and Infectious Diseases in South India  

Microsoft Academic Search

It has been said that the grandest genetic experiment of nature has been conducted in south India in the name of the caste system. One can expect the frequency of an infectious disease to be equal to the product of the frequencies of various indicated loci\\/alleles, whether physiological, hormonal or immunological, in an endemic area. The sympatrically isolated caste and

R. M. Pitchappan

2002-01-01

342

AERIAL VIEW OF MC WANE CAST IRON PIPE, LOOKING WEST ...  

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

AERIAL VIEW OF MC WANE CAST IRON PIPE, LOOKING WEST TO BIRMINGHAM CITY CENTER. I-20-59 RUNNING DIAGONALLY FROM RIGHT MIDDLE GROUND. L&N RAILROAD TRACKS IN FOREGROUND. - McWane Cast Iron Pipe, 1201 Vanderbilt Road , Birmingham, Jefferson County, AL

343

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

344

Explosive Comparison Trials; Cast TNT and TNT Drill Dust.  

National Technical Information Service (NTIS)

A series of six blast experiments was conducted to compare the blast environments produced by Cast TNT (military TNT Demolition Charge blocks) and by TNT Drill Dust, a by-product of reclaiming cast TNT from decommissioned military ordnance. Each experimen...

K. J. Knox T. J. Shelley

2005-01-01

345

Two from One Casting. Art Education: 6681.20.  

ERIC Educational Resources Information Center

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,…

Hilf, Anne

346

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

347

Remote Sensing and Cast Shadows in Mountainous Terrain  

Microsoft Academic Search

In mountainous environments with high relief, topographymay cause cast shadows due to the blocking of direct solar mdia- tion. Optical-injinred remote sensing images of these land- scapes display reduced values of reflectance for shadowed areas compared to non-shadowed areas with similar surjace cover characteristics. Different approaches to dealing with cast shadows are possible, although a common step in various active

Phlllp T. Glles

2001-01-01

348

Combined experimental and modeling approach to uranium casting.  

National Technical Information Service (NTIS)

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 c...

D. Korzekwa P. Dunn

1994-01-01

349

Method of fabricating a prestressed cast iron vessel  

Microsoft Academic Search

A method of fabricating a prestressed cast iron vessel is described wherein double wall cast iron body segments each have an arcuate inner wall and a spaced apart substantially parallel outer wall with a plurality of radially extending webs interconnecting the inner wall and the outer wall, the bottom surface and the two exposed radial side surfaces of each body

Lampe

1982-01-01

350

Method of fabricating a prestressed cast iron vessel  

Microsoft Academic Search

A method of fabricating a prestressed cast iron vessel wherein double wall cast iron body segments each have an arcuate inner wall and a spaced apart substantially parallel outer wall with a plurality of radially extending webs interconnecting the inner wall and the outer wall, the bottom surface and the two exposed radial side surfaces of each body segment are

Lampe; Robert F

1982-01-01

351

Method of fabricating a prestressed cast iron vessel  

Microsoft Academic Search

A method of fabricating a prestressed cast iron vessel wherein double wall cast iron body segments each have an arcuate inner wall and a spaced apart substantially parallel outer wall with a plurality of radially extending webs interconnecting the inner wall and the outer wall; the bottom surface and the two exposed radial side surfaces of each body segment are

Lampe

1980-01-01

352

MODELING SMALL FATIGUE CRACK GROWTH IN CAST ALUMINUM ALLOYS  

Microsoft Academic Search

The fatigue life of cast aluminum automotive engine components is, in some cases, controlled by the growth of small crack from pores rather than fatigue crack initiation. A method has been devised to efficiently measure the growth rates of small cracks initiating from micronotches produced by femtosecond pulsed laser machining. Two cast aluminum alloys, W319 with an overaged (T6) heat

A. Shyam; J. E. Allison; J. W. Jones

353

Investigation of the Viscosity of Molten Cast Iron.  

National Technical Information Service (NTIS)

The viscosity of cast irons of the systems Fe-C, Fe-C-Si; and Fe-C-Si-Al was measured at 1280-1460 degrees. The aim of the work was to study the 'heredity' of the castings whose properties depend on the starting material. The results confirm the existence...

I. Nakagawa

1972-01-01

354

Reaction synthesis of carbide-reinforced cast iron  

Microsoft Academic Search

Cast irons have found widespread uses as a result of their comparative low cost and their diversity of engineering properties. The low coefficient of friction of grey cast iron has led to its use in applications involving sliding surfaces such as piston rings, cylinder bores and brake discs in the automotive industry. Good sliding wear resistance is therefore one of

A. Chrysanthou; N. W. Davies; J. Li; P. Tsakiropoulos; O. S. Chinyamakobvu

1996-01-01

355

Abrasion wear behaviour of alloyed and chilled cast irons  

Microsoft Academic Search

High-chromium white cast irons are widely used in a variety of applications that require high wear resistance. This outstanding performance is due to the presence of large amounts of chromium carbides which exhibit high hardness. However, for wear-resistant applications exposed to impact, ductile cast iron is a candidate material due to its good wear behaviour, reduced brittleness and lower production

L. Ribeiro; A. Barbosa; F. Viana; A. Monteiro Baptista; C. Dias; C. A. Ribeiro

2011-01-01

356

Production scheduling in a steelmaking-continuous casting plant  

Microsoft Academic Search

In this paper we describe an optimization procedure for planning the production of steel ingots in a steelmaking-continuous casting plant. The strict requirements of the production process defeated most of the earlier approaches to steelmaking-continuous casting production scheduling, mainly due to the lack of information in the optimization models. Our formulation of the problem is based on the alternative graph,

Dario Pacciarelli; Marco Pranzo

2004-01-01

357

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

358

Control design and implementation in continuous steel casting  

Microsoft Academic Search

Accurate control of the mold level in continuous casting is believed to be a key factor in improving the quality of the cast product. This paper describes an application of advanced control to this problem leading to a complete recommissioning of the mold level control system. Careful physical modeling identified smooth as well as nonsmooth nonlinearities in the process. Three

S. F. Graebe; G. C. Goodwin; G. Elsley

1995-01-01

359

Ultrasonic detection of heat fronts in continuously cast steel product  

Microsoft Academic Search

Measurement of process parameters of continuously cast hot steel can play an important role in assessing the state of the casting process. One quantity of crucial importance is temperature, currently restricted to surface measurements using conventional optical pyrometers. A more useful quantity is internal temperature, and the authors discuss the application of ultrasonic time-of-flight methods to the harsh conditions of

Chris Baharis; Robert Cornish

1991-01-01

360

Tribological behavior of coatings for continuous casting of steel  

Microsoft Academic Search

There are a large number of steel making processes in which great demands are made on the surface behavior of several components that come into direct contact with steel under various conditions. Continuous casting is mainly a heat-extraction process. The mold must rapidly transfer heat from the steel to the cooling water. In continuous casting, steel solidification starts when it

Alejandro Sanz

2001-01-01

361

Flow structure in solidifying continuous-cast steel ingot  

Microsoft Academic Search

In producing continuous-cast slab, the melt motion in the liquid core of the ingot determines the rate of convective diffusion and thereby influences the development of chemical heterogeneity, the crystalline state, and the quality of the ingot. Experimental study of convection in continuous-cast ingots is complicated by the high melt temperature. Accordingly, mathematical simulation of the process is of great

A. N. Cherepanov; V. N. Popov; V. P. Komshukov; D. B. Foigt

2007-01-01

362

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...

363

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

364

The Childhood Autism Spectrum Test (CAST): Sex Differences  

ERIC Educational Resources Information Center

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…

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

2008-01-01

365

Moving Cast Shadow Detection of Vehicle Using Combined Color Models  

Microsoft Academic Search

Moving cast shadow detection of vehicle is important to vehicle detection and tracking. In this paper, a novel moving cast shadow detection approach using combined color models is proposed. Firstly, the ratio of hue over intensity in HSI color model is used to detect the bright object pixels in foreground regions. Secondly, we employ the theory of photometric color invariants

Bangyu Sun; Shutao Li

2010-01-01

366

A future vision for the investment casting industry  

SciTech Connect

All of American industry is being subjected to increased competitive pressures due to customer needs for shorter cycle times and better quality. The investment casting industry could be in a unique position to satisfy these needs by incorporating several emerging technologies into production processes. The inherent versatility and flexibility of casting make it a truly agile manufacturing process. Because of its compatibility with new rapid prototyping technologies, investment casting could be one of the key vehicles in the new ``art to part`` paradigm. Recently, dramatic advances have been made in the quality of wax and plastic patterns, parts, and tooling by investment casting on time scales unheard of today. Because design and acquisition of tooling contributes heavily to the lead time for any market, these advances will strengthen the position of investment casting manufacturers and customers, and create opportunities in traditional and non-tradition markets. Key to achieving this goal is to use the technology to remove uncertainties from investment casting process. To do this, we must collectively build the infrastructure to enable investment casting companies to make parts right the first time, every time. Integration of mature and on-the-horizon technologies will make this revolution possible and create large growth in markets for investment castings.

Zanner, F.J.; Maguire, M.C.

1993-11-01

367

Nature versus nurture in social insect caste differentiation  

Microsoft Academic Search

Recent evidence for genetic effects on royal and worker caste differentiation from diverse social insect taxa has put an end to the view that these phenotypes stem solely from a developmental switch controlled by environmental factors. Instead, the relative influences of genotypic and environmental effects on caste vary among species, ranging from largely environmentally controlled phenotypes to almost purely genetic

Tanja Schwander; Nathan Lo; Madeleine Beekman; Benjamin P. Oldroyd; Laurent Keller

2010-01-01

368

Tensile properties of as-cast iron-aluminide alloys  

SciTech Connect

Room-temperature tensile properties of as-cast Fe{sub 3}Al, Fe{sub 3}Al with chromium, and Fe{sub 3}Al-based FA-129 alloy are investigated. Tensile properties were obtained in the as-cast condition and after homogenization at 700, 900, and 1200{degrees}C. Transmission electron microscopy (TEM) was used to characterize ordered phases, and optical metallography and scanning electron microscopy (SEM) were used to characterize the microstructure and fracture morphology. The results indicate that the low ductility of as-cast Fe{sub 3}Al-based alloys may be related to the relatively large grain size in the cast condition, the low dislocation density in as-cast samples, and the presence of the D0{sub 3} ordered phase. Homogenized samples of FA-129 alloy exhibited almost twice the ductility of the as-cast condition. Microstructural characterization of the homogenized samples and comparison of the as-cast and homogenized microstructures may provide a clue to the poor ductility in the as-cast state.

Viswanathan, S.: McKamey, C.G.; Maziasz, P.J.; Sikka, V.K.

1993-07-01

369

Design for Chemical and Physical Properties of Continuous Casting Powders,  

National Technical Information Service (NTIS)

As the properties required of continuous casting powders differ with casting conditions, a study was made of the design of the desired powder properties. To obtain the optimum molten powder layer thickness d, it is necessary to select the powder melting r...

K. Koyama Y. Nagano K. Nagano T. Nakano

1987-01-01

370

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

371

The structures of fully eutectic aluminium-silicon alloy castings  

Microsoft Academic Search

Strontium-modified aluminium alloys containing 14 to 15 wt% silicon were cast with fully eutectic structures by using heated moulds and high-purity materials. In alloys containing the additional elements magnesium, copper or nickel, a distinct eutectic colony structure was evident outlined by intermetallic compounds. At the edges of the castings the eutectic colony structures and the aluminium grains (revealed by anodizing)

T. B. Abbott; B. A. Parker

1990-01-01

372

Tape Casting and Partial Melting of Bi-2212 Thick Films.  

National Technical Information Service (NTIS)

To produce Bi-2212 thick films with high critical current densities tape casting and partial melting is a promising fabrication method. Bi-2212 powder and organic additives were mixed into a slurry and tape casted onto glass by the doctor blade tape casti...

1995-01-01

373

A quick esthetic remount cast for all-ceramic restorations.  

PubMed

A technique is presented for the expedited fabrication of a remount cast for the alteration of all-ceramic crowns and fixed partial dentures. The remount cast allows the laboratory technician to know the precise location of the gingival tissues and allows modification of all-ceramic restorations. PMID:20456029

Hansen, Paul A; Gist, Julie

2010-08-01

374

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 ...

375

The Perception and Content of Cast Shadows: An Interdisciplinary Review  

Microsoft Academic Search

Recently, psychologists have turned their attention to the study of cast shadows and demonstrated that the human perceptual system values information from shadows very highly in the perception of spatial qualities, sometimes to the detriment of other cues. However with some notable and recent exceptions, computer vision systems treat cast shadows not as signal but as noise. This paper provides

Hannah M. Dee; Paulo E. Santos

2011-01-01

376

Recycling of gamma titanium aluminide scrap from investment casting operations  

Microsoft Academic Search

In investment casting processes for TiAl alloys, a substantial amount of the original raw material does not end-up as a final product but is instead solidified in runners and feeders of the casting system or as a skull in the crucible. Because of the high prices for the virgin alloys, there is a strong interest in remelting this scrap. This

J. Reitz; C. Lochbichler; B. Friedrich

2011-01-01

377

The Childhood Asperger Syndrome Test (Cast): Test--Retest Reliability  

ERIC Educational Resources Information Center

The Childhood Asperger Syndrome Test (CAST) is a 37-item parental self-completion questionnaire to screen for autism spectrum conditions in research. Good test accuracy was demonstrated in studies with primary school aged children in mainstream schools. The aim of this study was to investigate the test-retest reliability of the CAST. Parents of…

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

2006-01-01

378

Modification of hypoeutectic low alloy white cast irons  

Microsoft Academic Search

In order to modify the continuous network of eutectic cementite normally found in low alloy white cast irons into a dispersive distribution, strategies of controlling the morphology of eutectic cementite by additives are discussed. Qualitative arguments are presented and applied to the development of a complex modifier REAINTi. With the addition of this modifier to low carbon white cast irons

Ma Qian; Wang Chaochang; Shoji Harada

1996-01-01

379

A Review of Methods for Automated Recognition of Casting Defects  

Microsoft Academic Search

Radioscopy is increasingly being used as a tool for non-destructive testing in industrial production. An example is the serial examination of cast light-alloy workpieces used in the car industry, like aluminum wheels and steering gears. The material defects occurring in the casting process such as cavity, gas, inclusion, and sponge must be detected to satisfy the security requirements; consequently, it

Domingo Mery; Thomas Jaeger; Dieter Filbert

380

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

SciTech Connect

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

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

2008-11-21

381

LOW-PRESSURE CASTING OF LM25 (Al7Si0.3  Mg) ALUMINIUM ALLOY  

Microsoft Academic Search

Low-pressure casting (LPC) is a specialized process for producing thin component castings of ferrous and nonferrous metals and alloys. This process has fewer casting and mold-filling problems than conventional processes like gravity and pressure-die casting, thus giving rise to castings with good mechanical properties. In the present study, LM25 (Al-7Si-0.3  Mg) aluminium alloy castings have been produced using indigenously designed

A. Srinivasan; U. T. S. Pillai; V. John; B. C. Pai

2005-01-01

382

Method and apparatus for planar drag strip casting  

DOEpatents

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.

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

1991-11-12

383

Method and apparatus for planar drag strip casting  

DOEpatents

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.

Powell, John C. (Pittsburgh, PA); Campbell, Steven L. (Middletown, OH)

1991-01-01

384

Bond strength of porcelain on cast vs. wrought titanium.  

PubMed

The bond strength of porcelain fused to cast and wrought titanium surfaces was calculated from fracture loads in a 4-point bending test. Two different porcelain were applied (O'Hara and Duceratin). The surface of Ti-cast specimens was treated in two different ways to produce variations in the impurity level before porcelain veneering. Microhardness measurements as well as scanning electron microscopy with EDX analysis were conducted. The results showed no significant difference in bond strength between the two porcelains. Nor was any difference in bond capacity found between thoroughly blasted castings and wrought titanium. Significantly lower bond strengths were observed for lightly blasted specimens and for specimens treated with Gold bonding agent. Impurities in the surface region of the castings were found to be due to contact with the investment during solidification. This indicates that a thin surface layer (50-100 microns) of the casting should be removed before firing of the porcelain. PMID:1631489

Dérand, T; Herø, H

1992-06-01

385

Grain Refinement of Permanent Mold Cast Copper Base Alloys  

SciTech Connect

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.

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

2005-04-01

386

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

PubMed

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

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

2006-03-01

387

Casting defects and fatigue strength of a die cast aluminium alloy: a comparison between standard specimens and production components  

Microsoft Academic Search

The influence of casting defects on static and fatigue strength is investigated for a high pressure die cast aluminium alloy. Defects exist in gas and shrinkage pores as well as cold fills, dross and alumina skins. For the three batches of specimens, differing for the sprue–runner design, the influence was straightforward, while no significant variation in the fatigue strength was

M. Avalle; G. Belingardi; M. P. Cavatorta; R. Doglione

2002-01-01

388

Fabrication of high chromium cast iron and medium carbon steel bimetal by liquid–solid casting in electromagnetic induction field  

Microsoft Academic Search

The high chromium cast iron and medium carbon steel bimetal was fabricated by liquid–solid casting in electromagnetic induction field. The interfacial structure and mechanical properties were investigated. The results show that the microstructure is refined obviously and mechanical properties are improved significantly. The electromagnetic stirring can refine effectively the microstructure, and profit the diffusion of elements and obtaining of the

Bowen Xiong; Changchun Cai; Hong Wan; Baiping Lu

2011-01-01

389

Simulation of continuous-casting process (reconsideration of heat balance and improvement of efficiency in continuous-casting process)  

Microsoft Academic Search

A horizontal continuous-casting process was simulated. In the model, heat transfer of the whole system including the casting machine was considered. Temperature distribution and heat flux under normal operating conditions are presented and the heat-transfer characteristics were clarified. Conditions in the calculation, such as thermal resistance of mold section, and of carbon liner, inlet temperature of cooling water, its flow

Akio Saito; Seiji Okawa; Kentaro Kaneko; Hideo Kaneko

1994-01-01

390

Low speed centrifugal casting of Functionally Graded solid cast ingot by anomalous particle distribution  

NASA Astrophysics Data System (ADS)

Functionally graded cylindrical ingot of Al-Al2O3 composite synthesized by centrifugal casting shows particle distribution and hardness decreasing radially from the outer radius to inner radius. The progressive decrease in alumina content and hardness from the outer radius towards the center may be attributed to higher centrifugal force acting on relatively denser alumina particles during rotation, as compared to that acting on lighter alloy melt. It is also observed, as one moves down from the top to the bottom of cast ingot the alumina content decreases. This is surprising in view of higher density of alumina particles relative to the melt. The particle settling should have resulted at more particles towards the bottom, but distribution observed is in contradiction.

Mer, K. K. S.; Ray, S.

2011-12-01

391

Search for solar axions: the CAST experiment  

SciTech Connect

thetical axion-like particles with a two-photon interaction would be produced in the sun by the Primakoff process. In a laboratory magnetic field they would be transformed into X-rays with energies of a few keV. The CAST experiment at CERN is using a decommissioned LHC magnet as an axion helioscope in order to search for these axion-like particles. The analysis of the 2003 data showed no signal above the background, thus implying an upper limit to the axion-photon coupling of ga{gamma} < 1.16 x 10-10 GeV-1 at 95% CL for ma < or approx. 0.02 eV. The stable operation of the experiment during 2004 data taking allowed us to lower down this parameter to a preliminary value of ga{gamma} < 0.9 x 10-10 GeV-1.

Andriamonje, S.; Aune, S.; Ferrer-Ribas, E.; Giomataris, I. [DAPNIA, Centre d'Etudes Nucleaires de Saclay (CEA-Saclay), Gif-sur-Yvette (France); Barth, K.; Davenport, M.; Lasseur, C.; Papaevangelou, T.; Placci, A.; Stewart, L.; Walckiers, L. [European Organization for Nuclear Research (CERN), Geneve (Switzerland); Belov, A.; Gninenko, S. [Institute for Nuclear Research (INR), Russian Academy of Sciences, Moscow (Russian Federation); Beltran, B. [Instituto de Fisica Nuclear y Altas Energias, Universidad de Zaragoza, Zaragoza (Spain); DAPNIA, Centre d'Etudes Nucleaires de Saclay (CEA-Saclay), Gif-sur-Yvette (France); Braeuninger, H.; Englhauser, J.; Friedrich, P. [Max-Planck-Institut fuer extraterrestrische Physik, Garching (Germany); Carmona, J. M.; Cebrian, S.; Luzon, G. [Instituto de Fisica Nuclear y Altas Energias, Universidad de Zaragoza, Zaragoza (Spain)] (and others)

2006-11-28

392

Biomimetic membrane arrays on cast hydrogel supports.  

PubMed

Lipid bilayers are intrinsically fragile and require mechanical support in technical applications based on biomimetic membranes. Tethering the lipid bilayer membranes to solid substrates, either directly through covalent or ionic substrate-lipid links or indirectly on substrate-supported cushions, provides mechanical support but at the cost of small molecule transport through the membrane-support sandwich. To stabilize biomimetic membranes while allowing transport through a membrane-support sandwich, we have investigated the feasibility of using an ethylene tetrafluoroethylene (ETFE)/hydrogel sandwich as the support. The sandwich is realized as a perforated surface-treated ETFE film onto which a hydrogel composite support structure is cast. We report a simple method to prepare arrays of lipid bilayer membranes with low intrinsic electrical conductance on the highly permeable, self-supporting ETFE/hydrogel sandwiches. We demonstrate how the ETFE/hydrogel sandwich support promotes rapid self-thinning of lipid bilayers suitable for hosting membrane-spanning proteins. PMID:21526805

Roerdink Lander, Monique; Ibragimova, Sania; Rein, Christian; Vogel, Jörg; Stibius, Karin; Geschke, Oliver; Perry, Mark; Hélix-Nielsen, Claus

2011-06-01

393

Fractal structures in casting films from chlorophyll  

NASA Astrophysics Data System (ADS)

Chlorophyll (Chl) molecules are important because they can act as natural light-harvesting devices during the photosynthesis. In addition, they have potential for application as component of solar cell. In this work, we have prepared casting films from chlorophyll (Chl) and demonstrated the occurrence of fractal structures when the films were submitted to different concentrations. By using optical microscopy and the box-count method, we have found that the fractal dimension is Df = 1.55. This value is close to predicted by the diffusion-limited aggregation (DLA) model. This suggests that the major mechanism – which determines the growth of the fractal structures from Chl molecules – is the molecular diffusion. Since the efficiencies of solar cells depend on the morphology of their interfaces, these finds can be useful to improve this kind of device.

Pedro, G. C.; Gorza, F. D. S.; de Souza, N. C.; Silva, J. R.

2014-04-01

394

Cast thermally stable high temperature nickel-base alloys and casting made therefrom  

Microsoft Academic Search

A cast thermally stable high temperature nickel-base alloy characterized by superior oxidation resistance, sustainable hot strength and retention of ductility on aging is provided by maintaining the alloy chemistry within the composition molybdenum 13.7% to 15.5%; chromium 14.7% to 16.5%; carbon up to 0.1%, lanthanum in an effective amount to provide oxidation resistance up to 0.08%; boron up to 0.015%;

D. A. Acuncius; R. B. Herchenroeder; R. W. Kirchner; W. L. Silence

1977-01-01

395

Erosion of white cast irons and stellite  

SciTech Connect

The erosion behavior of dual-phase alloys containing large, hard carbides has been investigated. A series of high Cr-Mo white cast irons with a systematic variation of carbide volume fraction (CVF) and powder metallurgy specimens of Stellite 6 were eroded with alumina, crushed quartz and rounded quartz particles. These erodents were chosen because quartz has a hardness between that of the matrix and the Cr-rich carbides, whereas the hardness of alumina is comparable to that of the carbides. In addition, comparison of the results with crushed quartz and alumina allows an evaluation of the effect of particle hardness while the differences between the rounded and crushed quartz results can be attributed to the shape difference. For all erodents and alloys, the dependence of erosion on angle of incidence was weak. With alumina and rounded quartz erodents, the erosion rate increased with increasing CVF, while the reverse was true with crushed quartz. The crushed quartz erodent gave an erosion rate only slightly lower than that of alumina, indicating that the carbide erosion resistance is not a strong function of erodent particle hardness in this range of hardness. Scanning electron microscope (SEM) observations of the eroded surfaces showed that erosion of the highest-CVF white cast iron alloy with alumina or rounded quartz resulted in depression of the large primary carbides, while with crushed quartz many of the carbides protruded above the matrix. The SEM and erosion rate observations show that with crushed quartz the carbides are more erosion resistant than the eutectic matrix and that the carbides therfore contribute to erosion resistance, while with the other erodents the reverse is true. 17 refs., 15 figs., 2 tabs.

Aptekar, S.S.; Kosel, T.H.

1985-01-01

396

A dynamic control water distribution model of steel in continuous casting  

NASA Astrophysics Data System (ADS)

After investigation in many continuous casting shop of steel, a dynamic water distribution model is proposed for flexible control on secondary cooling in continuous casting. In this model, the water cooling intensity is determined by the model casting speed instead of the real casting speed. When the casting speed is steady, the model casting speed is equal to the real casting speed. When the real casting speed is changing, the model casting speed according to calculating algorithm to adjust and approaches to the real one, but there is a time delay between them, so it can avoid the slab surface temperature fluctuated due to casting speed changes. The secondary cooling can be dynamically controlled by monitoring the model casting speed. The compare of the simulation results and the measured results reveals that the temperature field and thickness of slab shell in simulations agree very well with the real production situations.

Fu, Jian-Xun; Hwang, Weng-Sing; Tsai, De-Chang; Tsai, MingHsiu; Wang, Chien-Hsun

2012-07-01

397

Development of a CFD code for casting simulation  

NASA Technical Reports Server (NTRS)

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.

Murph, Jesse E.

1993-01-01

398

Columnar to equiaxed transition in high Cr white iron castings  

SciTech Connect

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.

Dogan, O.N. [Bureau of Mines, Albany, OR (United States)] [Bureau of Mines, Albany, OR (United States)

1996-07-15

399

Casting accuracy of experimental Ti-Cu alloys.  

PubMed

The purpose of the present study was to investigate the casting accuracy and the dimensional change of experimental titanium-copper alloys (3.0 and 5.0 mass% Cu; hereafter, only "%" will be used) and to compare the findings with those of pure titanium. Castings were made using an argon-arc melting/pressure difference-casting unit. The fit of the metals cast in both full crown and MOD inlay dies was evaluated by measuring the distance between the shoulder margin and the cervical shoulder of the die. The changes in the inner diameter of castings were determined. In addition, surface roughness measurements inside the castings were carried out using a conventional profilometer, and thermal expansion measurements were made on cast cylindrical specimens using a differential dilatometer. There were no significant differences in dimensional change between pure titanium and the titanium-copper alloys. The fit of the titanium-copper alloys was inferior to pure titanium. The results of surface roughness measurements showed significance differences between the roughness of the pure titanium and titanium-copper alloys. PMID:11441485

Hattori, M; Hasegawa, K; Yoshinari, M; Kawada, E; Oda, Y; Okabe, T

2001-03-01

400

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

NASA Astrophysics Data System (ADS)

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.

Krishna, Prasad

2001-08-01

401

Stress Corrosion Cracking Behavior of Cast Stainless Steels  

SciTech Connect

Casting of austenitic stainless steels offers the possibility of directly producing large and/or relatively complex structures, such as the first wall shield modules or the diverter cassette for the ITER fusion reactor. Casting offers major cost savings when compared to fabrication via welding of quarter modules machined from large forgings. However, the strength properties of such cast components are typically considered inferior to those of conventionally forged and annealed components. To improve and validate cast stainless steel as a substitute for wrought stainless steel, a development and testing program was initiated, utilizing nitrogen and manganese additions to promote improved performance. This paper focuses on the response of the first set of developmental alloys to neutron-irradiation and susceptibility to stress corrosion cracking. These cast materials may also have applications for different components in light water reactors. Results showed that all steels exhibited irradiation-induced hardening and a corresponding drop in ductility, as expected, although there is still considerable ductility in the irradiated samples. The cast steels all exhibited reduced hardening in comparison to a wrought reference steels, which may be related to a larger grain size. Higher nitrogen contents did not negatively influence irradiation performance. Regarding stress corrosion cracking susceptibility, the large difference in grain size limits the comparison between wrought and cast materials, and inclusions in a reference and archive cast alloy tests complicate analysis of these samples. Results suggest that the irradiated archive heat was more susceptible to cracking than the modified alloys, which may be related to the more complex microstructure. Further, the results suggest that the modified cast steel is at least as SCC resistant as wrought 316LN. The beneficial effect of nitrogen on the mechanical properties of the alloys remains after irradiation and is not detrimental to SCC resistance.

Teysseyre, Sebastien [University of Michigan; Busby, Jeremy T [ORNL; Was, Gary [University of Michigan

2009-01-01

402

Method to prevent/mitigate steam explosions in casting pits  

DOEpatents

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.

Taleyarkhan, Rusi P. (Knoxville, TN)

1996-01-01

403

Freeze Tape Casting of Functionally Graded Porous Ceramics  

NASA Technical Reports Server (NTRS)

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.

Sofie, Stephen W.

2007-01-01

404

Shrinkage Prediction for the Investment Casting of Stainless Steels  

SciTech Connect

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.

Sabau, Adrian S [ORNL

2007-01-01

405

X-ray detectors of the CAST experiment  

NASA Astrophysics Data System (ADS)

CERN Axion Solar Telescope (CAST) is an experiment probing hypothetical particles: the axions, created in the solar core. Inside the transverse magnetic field of the CAST magnet, axions can be converted into x-rays, and be detected by four x-ray detectors at CAST. The expected x-ray signal in CAST is in 1–10 keV range, intensity depending strongly on the coupling constant of axion-photon conversion ga?, which is expected to be low. This requires CAST to have detectors with very low background levels. The CAST Experiment makes use of three Micromesh Gaseous Structure (micromegas) detectors, which are gaseous detectors, derived from ideas of Multiwire Proportional Chambers (MWPC). CAST Micromegas detectors show perfect stability, good spatial and energy resolution. The intense study on Micromegas has enabled CAST to understand the nature of its background level, and improve it by a factor of 102 over ten years. New detector design, new readout system, better cosmic veto and addition of x-ray telescope will further improve the background in the next data taking of the experiment. The Charge-Coupled Device (CCD) of CAST is a pn-CCD detector with 200 × 64 pixels. The CAST CCD is coupled to an X-ray telescope, focusing all the parallel x-rays into a 9 mm diameter spot. The CCD will be replaced by the InGrid detector, a special manufactured micromegas detector. It is able to detect single electrons, and the low energy capabilities will open new frontiers on search of axions and other exotic particles. Another option is the Silicon Drift Detector (SDD), which is being tested in 2013, and has an energy threshold as low as 250 eV. The CAST experiment is the pioneering helioscope that excludes an important part of axion mass-coupling constant parameter space, and expects to exclude more in the following years. To succeed CAST, a new experiment, the International AXion Observatory (IAXO) is being designed and optimised, comprising the construction of a magnet specially built for axion search as well as new detectors that will enable to improve the actual limits by 1–1.5 orders of magnitude.

Yildiz, S. C.

2014-03-01

406

Design and Analysis for Melt Casting Metallic Fuel Pins  

SciTech Connect

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)

Wu, Xiaolong; Clarksean, Randy; Chen, Yitung [Department of Mechanical Engineering, University of Nevada, Las Vegas (United States); Meyer, Mitchell K. [Nuclear Technology Division, Argonne National Laboratory, Idaho Falls, ID (United States)

2002-07-01

407

An accelerated clinical chairside technique for casting overdenture attachment copings.  

PubMed

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

Scherer, Michael D; Campagni, Wayne V

2011-11-01

408

A combined experimental and modeling approach to uranium casting  

SciTech Connect

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.

Korzekwa, D.; Dunn, P.

1994-08-01

409

Biomechanical effects of rockers on walking in a plaster cast.  

PubMed

Rockers are applied to lower limb casts to assist walking but there is little information on their biomechanical effects. The performances of 10 commercially available rockers were compared. They were applied to a below-knee cast worn by a normal subject who was also tested walking in the cast alone. Gait analysis was used to evaluate kinematic and kinetic data. The design of rocker had no effect upon the kinematics of walking. However, using new criteria for kinetic assessment of rocker function (tibial floor angular velocity and centre of pressure progression), most designs had a deleterious effect on the biomechanics of gait. Only two rockers approached the ideal kinetic criteria. PMID:1991786

Hullin, M G; Robb, J E

1991-01-01

410

Optimization of Squeeze Casting for Aluminum Alloy Parts  

SciTech Connect

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.

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

2002-07-30

411

Why cast shadows are expendable: insensitivity of human observers and the inherent ambiguity of cast shadows in pictorial art.  

PubMed

The kinds of visual cues artists choose to use or not use in their work can offer insight into perceptual processes. On the basis of the observed paucity of the use of cast shadow in pictorial art, we hypothesized that cast shadows might be relatively expendable as pictorial cues. In this study, we investigated two potential reasons for this expendability: first, viewers might be insensitive to much of the information that cast shadows provide; and, second, ambiguities about what is shadow and what is pigment can often be resolved only through motion-something that static media are ill-equipped to deal with. In experiment 1, we used a visual-search paradigm in which viewers had to determine if there were odd cast shadows in sets of 4, 8, 16, and 32 objects. In experiment 2, viewers had to discriminate between shadow/pigment ambiguities in both still and moving images. Our results demonstrate that viewers are neither particularly sensitive to static cast-shadow incongruities, nor are they able to disambiguate cast shadow from pigment without continuous motion information. Taken together, these results may help explain why cast shadows are relatively rare in static pictorial work. PMID:15693677

Jacobson, Jayme; Werner, Steffen

2004-01-01

412

Directional migration in the Hindu castes: inferences from mitochondrial, autosomal and Y-chromosomal data  

Microsoft Academic Search

Genetic, ethnographic, and historical evidence suggests that the Hindu castes have been highly endogamous for several thousand years and that, when movement between castes does occur, it typically consists of females joining castes of higher social status. However, little is known about migration rates in these populations or the extent to which migration occurs between caste groups of low, middle, and

Stephen Wooding; Christopher Ostler; B. V. Ravi Prasad; W. Scott Watkins; Sandy Sung; Mike Bamshad; Lynn B. Jorde

2004-01-01

413

Optimization of green sand casting process parameters by using Taguchi’s method  

Microsoft Academic Search

This paper analyses various significant process parameters of the green sand casting process. An attempt has been made to obtain optimal settings of the green sand casting process in order to yield the optimum quality characteristics of the spheroidal graphite (SG) cast iron rigid coupling castings. The process parameters considered are: green strength, moisture content, permeability and mould hardness. The

S. Guharaja; A. Noorul Haq; K. M. Karuppannan

2006-01-01

414

Effect of Thermomechanical Treatments on the Aging Response of Centrifugally Cast Silicon Carbide/Aluminum Composites.  

National Technical Information Service (NTIS)

Differential scanning calorimetry was conducted using centrifugally cast monolithic A356 aluminum material and 26 volume percent silicon carbide (SiC) particle reinforced A356 aluminum matrix composite material in as-cast, cast and rolled, and cast and ex...

C. W. May

1992-01-01

415

Inference of optimal speed for sound centrifugal casting of Al12Si alloys  

Microsoft Academic Search

True centrifugal casting is a standard casting technique for the manufacture of hollow, intricate and sound castings without the use of cores. The molten metal or alloy poured into the rotating mold forms a hollow casting as the centrifugal forces lift the liquid along the mold inner surface. When a mold is rotated at low and very high speeds defects

Shailesh Rao Agari; P. G. Mukunda; Shrikantha S. Rao; K. G. Sudhakar

2011-01-01

416

Energy and Technology Assessment of Zinc and Magnesium Die Casting Plants. Technical Report Close-Out.  

National Technical Information Service (NTIS)

Twin City Die Castings Company of Minneapolis, Minnesota, Twin City Die Castings Company was awarded project No. DE-FG36-05GO15097 to perform plant wide assessments of ten (10) die casting facilities that produce zinc and magnesium alloy castings in order...

T. Heider

2006-01-01

417

The taper of cast post preparation measured using innovative image processing technique  

Microsoft Academic Search

BACKGROUND: No documentation in the literature about taper of cast posts. This study was conducted to measure the degree of cast posts taper, and to evaluate its suitability based on the anatomy aspects of the common candidate teeth for post reconstruction. METHODS: Working casts for cast posts, prepared using Gates Glidden drills, were collected. Impressions of post spaces were made

Khaled Q Al Hamad; Faruq A Al-Omari; Ahmad S Al Hyiasat

2010-01-01

418

75 FR 70900 - Certain Iron Construction Castings From Brazil, Canada, and the People's Republic of China...  

Federal Register 2010, 2011, 2012, 2013

...Iron Construction Castings From Brazil, Canada, and the People's Republic of China...castings (``castings'') from Brazil, Canada, and the People's Republic of China...the AD orders on castings from Brazil, Canada, and the PRC and the CVD order on...

2010-11-19

419

Clean ferrous casting technology research. Final technical report, September 29, 1993--December 31, 1995  

SciTech Connect

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.

Piwonka, T.S. [ed.

1996-01-01

420

Study of FES/CAST/HGS  

NASA Technical Reports Server (NTRS)

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.

Workman, Gary L.; Cummings, Rick; Jones, Brian

1992-01-01

421

Hot cracking during welding and casting  

NASA Astrophysics Data System (ADS)

Aluminum welds are susceptible to liquation cracking in the partially melted zone (PMZ). Using the multicomponent Scheil model, curves of temperature vs. fraction solid (T-fS) during solidification were calculated for the PMZ and weld metals (WMs). These curves were used to predict the crack susceptibility by checking if the harmful condition of WM fS > PMZ fS exists during PMZ solidification and reduce the susceptibility by minimizing this condition. This approach was tested against full-penetration welds of alloys 7075 and 2024 and it can be used to guide the selection or development of filler metals. Liquation cracking in the PMZ in welds of Al-Si cast alloys was also investigated. The crack susceptibility was evaluated by circular-patch test, and full-penetration welds made with filler metals 1100, 4043, 4047 and 5356. Liquation cracking was significant with filler metals 1100 and 5356 but slight with filler metals 4043 and 4047. In all welds, liquation cracks were completely backfilled, instead of open as in full-penetration welds of wrought alloys 2219 and 6061. The T-fS curves showed that alloy A357 has a much higher fraction liquid for backfilling before PMZ solidification was essentially over. Hot tearing in Mg-xAl-yCa alloys was studied by constrained rod casting (CRC) in a steel mold. The hot tearing susceptibility decreased significantly with increasing Ca content (y) but did not change much with the Al content (x). An instrumented CRC with a steel mold was developed to detect the onset of hot tearing. The secondary phases, eutectic content, solidification path, and freezing range were examined. Hot tearing in Mg-Al-Sr alloys was also studied by CRC in a steel mold. With Mg-(4,6,8)Al-1.5Sr alloys, the hot tearing susceptibility decreased significantly with increasing Al content. With Mg-(4,6,8)Al-3Sr alloys, the trend was similar but not as significant. At the same Al content, the hot tearing susceptibility decreased significantly with increasing Sr content. Instrumented CRC with a steel mold was also used to test hot tearing of Mg-Al-Sr alloys. Cracking occurred at a higher temperature in alloys most susceptible to cracking than in alloys least susceptible.

Cao, Guoping

422

Simulation of continuous-casting process (reconsideration of heat balance and improvement of efficiency in continuous-casting process)  

SciTech Connect

A horizontal continuous-casting process was simulated. In the model, heat transfer of the whole system including the casting machine was considered. Temperature distribution and heat flux under normal operating conditions are presented and the heat-transfer characteristics were clarified. Conditions in the calculation, such as thermal resistance of mold section, and of carbon liner, inlet temperature of cooling water, its flow rate, and withdrawal speed were varied and the thermal effect on the forming process of steel was studied. Furthermore, a guide to optimize the size of the casting machine to improve the efficiency of manufacturing is proposed.

Saito, Akio; Okawa, Seiji (Tokyo Inst. of Tech. (Japan). Dept. of Mechanical Science and Engineering); Kaneko, Kentaro; Kaneko, Hideo

1994-10-01

423

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

424

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

425

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

426

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

427

4. Pier detail, cast iron bollard, north side of pier, ...  

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

4. Pier detail, cast iron bollard, north side of pier, view to northwest. - Charlestown Navy Yard, Pier 11, Charlestown Waterfront at confluence of Little Mystic Channel & Mystic River at northernmost ent of Navy Yard, Boston, Suffolk County, MA

428

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

429

Bifilm Defects in Ni-Based Alloy Castings  

NASA Astrophysics Data System (ADS)

The Ni-base superalloys, which are normally melted and cast in a vacuum, entrain their surface-oxide film during turbulent pouring of the melt; unfortunately at this time, this process is universally practiced for investment castings of these materials. The entrained film becomes a bifilm crack automatically, so that cast alloys have a large population of cracks that controls their failure behavior. The problems of the growth of single crystals and the welding of polycrystalline alloys are reviewed to illustrate the central role of bifilms in the cracking of turbine blades, the heat-affected zones of welds, and the reliability of properties. It has been demonstrated that improved gravity pouring systems can reduce these problems significantly, but only countergravity filling of molds is expected to result in defect-free castings. Recent cases in which turbine blades failed in service are examined, and the central role of bifilm defects in these failures is discussed.

Campbell, John; Tiryakio?lu, Murat

2012-08-01

430

How to Identify and Control Cyclaneusma Needle Cast of Pines,  

National Technical Information Service (NTIS)

Cyclaneusma needle cast is caused by Cyclaneusma minus (=Naemacyclus minor) (Ascomycetes:Rhytisma-taceaae). In North America, this disease occurs from Virginia to Missouri northward through New England and southern Canada western Nebraska and Manitoba, pl...

W. Merrill K. Robbins

1987-01-01

431

Advanced lost foam casting technology. 1995 summary report.  

National Technical Information Service (NTIS)

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...

C. E. Bates H. E. Littleton D. Askeland J. Griffin B. A. Miller

1996-01-01

432

10. DETAIL OF CAST IRON COLUMN BASE ON FIRST FLOOR ...  

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

10. DETAIL OF CAST IRON COLUMN BASE ON FIRST FLOOR STOREFRONT, SHOWING MANUFACTURER'S STAMP: IOWA IRON WOKS CO. DUBUQUE. VIEW TO SOUTHWEST. - Commercial & Industrial Buildings, Dubuque Seed Company Warehouse, 169-171 Iowa Street, Dubuque, Dubuque County, IA

433

Integrated moving cast shadows detection method for surveillance videos  

NASA Astrophysics Data System (ADS)

Moving cast shadow detection plays an exceedingly important role in content-based analysis in surveillance videos. A novel integrated moving cast shadow detection method is proposed for accurate moving objects detection. Based on the analysis for shadow model, we first exploit color information sufficiently in hue, saturation, and value color space and texture similarity in texture space to separate moving cast shadows from the foreground, respectively. Then we obtain the rough shadow detection result by means of synthesizing the above two results efficiently. Finally, post processing is put forward to modify misclassified pixels for acquiring the refined shadow detection result. Extensive experiments and comparisons of various scenes prove that the proposed method can detect cast shadows automatically and effectively and outperforms some well-known methods.

Dai, Jiangyan; Qi, Miao; Yu, Xiaoxi; Kong, Jun

2012-11-01

434

49 CFR 192.755 - Protecting cast-iron pipelines.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 false Protecting cast-iron pipelines. 192.755 Section 192.755 Transportation...Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION...DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY TRANSPORTATION OF NATURAL...

2013-10-01

435

Web Cast on Arsenic Demonstration Program: Lessons Learned  

EPA Science Inventory

Web cast presentation covered 10 Lessons Learned items selected from the Arsenic Demonstration Program with supporting information. The major items discussed include system design and performance items and the cost of the technologies....

436

Photophysical Studies of Spin-Cast Polymer Films.  

National Technical Information Service (NTIS)

Spin casting is a commonly used technique for producing thin, uniform polymer films, especially for semiconductor fabrication. There has been little attention given to the response of the polymers at the molecular level, however. We have reviewed previous...

L. L. Kosbar S. W. Kuan C. W. Frank R. F. Pease

1989-01-01

437

Microstructure of thin-wall ductile iron castings  

SciTech Connect

Step plate castings with section thicknesses of 1.5 mm to 6 mm and individual (single) castings with section thicknesses of 2 mm to 6 mm were produced using a ductile iron chemistry. Microstructures of these thin wall ductal iron castings were characterized quantitatively using an image analyzer. Matrix structure (amount of pearlite, ferrite, and massive carbides) and graphite structure (volume fraction, nodule size, nodule content, and nodularity) were investigated as a function of section thickness. Pearlite content, nodule count, and nodularity increased with decreasing section thickness, whereas the nodule size decreased. Nodule content exceeded 2000 nodules per mm{sup 2} at the thinnest sections. Statistical analysis was performed to investigate the effect of casting parameters on the microstructure.

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

2003-01-01

438

Advanced lost foam casting technology. 1995 summary report  

SciTech Connect

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.

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

1996-05-01

439

Constructivist Learning of Anatomy: Gaining Knowledge by Creating Anatomical Casts  

NSDL National Science Digital Library

This article describes a method to promote inquiry based learning in the anatomy curriculum. The article describes a method requiring students to build casts of the bronchial tree and coronary arteries while faculty asked leading questions related to the material.

Heidi L. Lujan (Wayne State Univ Sch Med Dept of Physiology); Stephen E DiCarlo (Northeastern Ohio University College of Medicine Department of Physiology)

2011-03-01

440

Electroforming a Mold for Casting Plastic Fresnel Lenses.  

National Technical Information Service (NTIS)

The problems involved in diamond turning an aluminium mandrel and electroforming a negative off this mandrel from which lenses can be cast are described. Surface cleaning, parting the electroform from the mandrel, surface properties, and method modificati...

F. B. Waldrop R. C. Waldrop C. A. Washington H. F. Patterson

1979-01-01

441

Synthetic casting tape as a facial impression tray material.  

PubMed

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

Saunders, T R; Hansen, N A

1995-08-01

442

Tape casting of high dielectric ceramic substrates for microelectronics packaging  

NASA Astrophysics Data System (ADS)

The production of ceramic green tapes is integral to the production of multilayer ceramic packages and capacitors. This article presents a batch type process for producing alumina ceramic green tape down to 150 µm thickness. The process parameters relevant to the precise control of the thickness of an aluminabased ceramic tape have been investigated using a float glass tape caster. Results indicate that the cast tape thickness was dependent on the blade gap until it reached a limiting value. This limiting thickness in turn was dependent on the casting speed, with a higher speed producing thinner tapes. Optimal casting was shown to exist when the blade gap was set at or beyond the limiting value, with the casting speed the controlling factor for the final thickness.

Tok, A. I. Y.; Boey, F. Y. C.; Khor, M. K. A.

1999-08-01

443

Casting Stainless-Steel Models Around Pressure Tubes  

NASA Technical Reports Server (NTRS)

Survivability of thin-wall stainless-steel tubing increased to nearly 100 percent. Improves state of art in pressure-model castings and reduces cost associated with machining complete model from stainless-steel blank.

Vasquez, Peter; Micol, John R.

1992-01-01

444

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

445

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

446

Predicting Pattern Tooling and Casting Dimensions for Investment Casting, Phase II  

SciTech Connect

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 first part of the project involved preparation of reports on the state of the art at that time for all the areas under consideration (die-wax, wax-shell, and shell-alloy). The primary R&D focus during Phase I was on the wax material since the least was known about it. The main R&D accomplishments during this phase were determination of procedures for obtaining the thermal conductivity and viscoelastic properties of an unfilled wax and validating those procedures. Phase II focused on die-wax and shell-alloy systems. A wax material model was developed based on results obtained during the previous R&D phase, and a die-wax model was successfully incorporated into and used in commercial computer programs. Current computer simulation programs have complementary features. A viscoelastic module was available in ABAQUS but unavailable in ProCAST, while the mold-filling module was available in ProCAST but unavailable in ABAQUS. Thus, the numerical simulation results were only in good qualitative agreement with experimental results, the predicted shrinkage factors being approximately 2.5 times larger than those measured. Significant progress was made, and results showed that the testing and modeling of wax material had great potential for industrial applications. Additional R&D focus was placed on one shell-alloy system. The fused-silica shell mold and A356 aluminum alloy were 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. It was very important to obtain accurate temperature data from actual castings, and significant effort was made to obtain temperature profiles in the shell mold. A model for thermal radiation within the shell mold was developed, and the thermal model was successfully validated using ProCAST. 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 prefiring of the empty shell mold was considered in the model, and the shell mold was limited to a pure elastic material. The alloy dimensions were obtained from numerical simulations only with coupled shell-alloy systems. The alloy dimensions were in excellent quantitative agreement with experimental data, validating the deformation module. For actual parts, however, the creep properties of the shell molds must also be obtained, modeled, and validated.

Nick Cannell (EMTEC); Adrian S. Sabau (ORNL)

2005-09-30

447

Method of casting articles of a bulk-solidifying amorphous alloy  

DOEpatents

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.

Lin, Xianghong (Laguna Niguel, CA); Johnson, William L. (Pasadena, CA); Peker, Atakan (Aliso Viejo, CA)

1998-01-01

448

Microstructures and properties of aluminum die casting alloys  

SciTech Connect

This document provides descriptions of the microstructure of different aluminum die casting alloys and to relate the various microstructures to the alloy chemistry. It relates the microstructures of the alloys to their main engineering properties such as ultimate tensile strength, yield strength, elongation, fatigue life, impact resistance, wear resistance, hardness, thermal conductivity and electrical conductivity. Finally, it serves as a reference source for aluminum die casting alloys.

M. M. Makhlouf; D. Apelian; L. Wang

1998-10-01

449

On thermal shock resistance of austenitic cast irons  

Microsoft Academic Search

This research applied rapid induction heating and water quenching cycles to study the thermal shock resistance of high-nickel\\u000a austenitic cast irons. Both flake graphite (FG) and compacted graphite (CG) cast irons were evaluated. In addition, alloying\\u000a of cobalt and (Cr + Al) to the high-nickel base materials was performed to produce ultralow thermal expansion and hightemperature\\u000a specialty irons. Microstructural analysis,

Shen-Chih Lee; Lin-Chao Weng

1991-01-01

450

Creep studies of AZ91D pressure die casting  

Microsoft Academic Search

Creep properties of pressure die cast AZ91D magnesium alloy (9% Al-1% Zn) were investigated in the temperature range of 150–180 °C and load range of 30–100 MPa. The pressure die cast material is characterized by a small grain size of about 10 ?m. Creep tests were performed under constant load and under varying load. Creep rates were found to be

M. Regev; E. Aghion; A. Rosen

1997-01-01

451

Performance evaluation of PVD coatings for high pressure die casting  

Microsoft Academic Search

During high-pressure die-casting (HPDC) of aluminium alloys, there is a tendency for the molten alloy to react with the tool steel die, core pins and inserts. This occurrence within the high pressure die casting (HPDC) industry is referred to as ‘soldering’. It is of concern to high-pressure die casters because of down-time due to the regular removal of the soldered

S. Gulizia; M. Z. Jahedi; E. D. Doyle

2001-01-01

452

Numerical simulation of low pressure die casting of magnesium wheel  

Microsoft Academic Search

The application of magnesium in the automotive industry contributes to reduced fuel consumption and CO2 emissions. Nowadays, most magnesium components in automobiles are manufactured by die casting. In this paper, simulation\\u000a of the low pressure die casting process of a magnesium wheel that adopts FDM (finite difference method) is presented. Through\\u000a calculating the temperature and velocity fields during filling and

Ying-chun Wang; Da-yong Li; Ying-hong Peng; Xiao-qin Zeng

2007-01-01

453

Wear resistance of high-manganese steel castings  

Microsoft Academic Search

Conclusions 1.To improve the wear resistance of parts made of G13-L steel, the latter has to be paired at as low a temperature as possible.2.Castings (drag buckets, crusher cones and front ladle walls) should not contain more than 0.06–0.07% P and 0.5%–0.6% Si.3.The castings must be inspected for microstructure and impact toughness.

M. A. Guzovskaya; Ya. D. Khorin

1962-01-01

454

Dynamics of the guideway system founded on casting compound  

Microsoft Academic Search

The work presents a new technology for the assembly of ball guideway systems which involves the use of a thin layer of a casting\\u000a compound. The experimentally verified simulation research presented in the work indicates that the use of the casting compound\\u000a between the guide rail and the bed of the machine tool positively influences the dynamics of the system.

Bartosz Powa?ka; Tomasz Okulik

455

Overlapping Identities under Liberalization: Gender and Caste in India  

Microsoft Academic Search

This article reviews the major theories on identity and economic outcomes to reiterate that identity affects the material well-being of individuals. Based on two rounds of data from the National Family and Health Survey, this article attempts to examine changes in two of the several identities in India, namely, the gender-caste overlap. The Gender-Caste Development Index (GCDI) from an earlier

Ashwini Deshpande

2007-01-01

456

Embrittlement of cast stainless steels in LWR systems  

Microsoft Academic Search

Mechanical property data from Charpy-impact and J-R curve tests are presented for several experimental and commercial heats, as well as reactor-aged material of CF-3, CF-8, and CF-8M grades of cast stainless steel. The effects of material variables on the embrittlement of cast stainless steels are evaluated. The chemical composition and ferrite morphology have a strong effect on the extent and

O. K. Chopra; H. M. Chung

1989-01-01

457

Efficient Receipt-Free Ballot Casting Resistant to Covert Channels  

Microsoft Academic Search

Open-audit election protocols have, in recent years, focused on the ballot casting process, where the difficulty lies in proving to the unaided voter that the encrypted ballot faithfully captures her intent. We present MarkPledge2, an evolution of Neff's MarkPledge scheme and the first efficient, covert-channel-resistant, receipt-free ballot casting scheme that can be used by humans without trusted hardware. In comparison

Ben Adida; C. Andrew Neff

458

Formation of longitudinal, midface cracks in continuously-cast slabs  

Microsoft Academic Search

Based on a series of related investigations, a mechanism for the formation of longitudinal, midface cracks in strand-cast\\u000a slabs has been elucidated. Metallographic studies, X-ray analyses, and high-temperature tensile testing of as-cast slab samples,\\u000a together with computer predictions of heat flow, have been combined to show that the cracks open first close to the solidification\\u000a front where the ductility is

J. K. Brimacombe; F. Weinberg; E. B. Hawbolt

1979-01-01

459

Real-time simulation of heat transfer in continuous casting  

Microsoft Academic Search

A real-time heat-transfer model for continuous slab casting is presented. The model calculates the strand temperatures and\\u000a the solid shell thickness profile along the machine as a function of the actual casting variables, strand geometry, and steel\\u000a grade. The special requirements con-cerning the real-time use of the model and, in general, the accuracy of the model are\\u000a also studied and

Seppo Louhenkilpi; Erkki Laitinen; Risto Nieminen

1993-01-01

460

Corrosion resistant gray cast iron graphite flake alloys  

SciTech Connect

Corrosion resistant gray cast iron alloys useful in downhole oil well environments and the like. The alloys are substantially lower in cost and substantially higher in tensile strength than high nickel-copper cast irons commonly used downhole in submergible pumps. The alloys contain substantial amounts of aluminum in combination with nickel, chromium, manganese, molybdenum, carbon, silicon, and iron. Copper, tin, vanadium, and boron may also be included. Both hardenable and non-hardenable alloys are provided.

Betts, B. A.

1985-10-22

461

Corrosion behavior between dental implant abutment and cast gold alloy  

Microsoft Academic Search

Two types of HL hexed abutments of a Steri-Oss system, gold\\/plastic coping and gold coping, were compared in terms of corrosion\\u000a behavior. The anodic polarization behavior and the galvanic corrosion between abutments and Type III gold alloys, before and\\u000a after casting, were analyzed. In addition, the crevice corrosion of the casting samples was analyzed with cyclic potentiodynamic\\u000a polarization tests using

Mi-Kyoung Son; Han-Cheol Choe; Chae-Heon Chung

2004-01-01

462

Metallographic Characterization of Hypoeutectic Martensitic White Cast Irons  

Microsoft Academic Search

High wear resistance and low cost are among the most appreciated properties for the non-alloyed white cast irons. Their toughness levels, however, are poor. An attempt to optimize the compromise between abrasive wear resistance and impact toughness could be reached through the use of low-alloy Ni-Hard cast irons satisfying the majority of mining applications in mineral crushing, classification, and transportation.

J. A. Pero-Sanz; D. Plaza; J. I. Verdeja; J. Asensio

1999-01-01

463

Solidification of binary hypoeutectic alloy matrix composite castings  

Microsoft Academic Search

We consider a binary hypoeutectic alloy casting which solidifies in dendritic form in an unreinforced engineering casting\\u000a and seek to predict its microstructure in a metal matrix composite. We focus on the case where the reinforcement is fixed\\u000a in space and fairly homogeneously distributed. We assume that the reinforcement does not catalyze heterogeneous nucleation\\u000a of the solid. We show that

Andreas Mortensen; Merton C. Flemings

1996-01-01

464

The squeeze casting of hypoeutectic binary Al-Cu  

Microsoft Academic Search

A combination of thermocouple measurements, optical microscopy, and image analysis has been used to investigate the effects\\u000a of applied pressure, melt temperature, mould insulation, and addition of grain refiner on the cooling\\/solidification behavior\\u000a and resulting macro-and microstructure in squeeze cast Al-4.5 wt pct Cu ingots. Channel macrosegregates are formed in Al-4.5\\u000a wt pct Cu squeeze castings because of an increased

M. Gallerneault; G. Durrant; B. Cantor

1996-01-01

465

Cast-to-shape electrokinetic trapping medium  

DOEpatents

A three-dimensional microporous polymer network material, or monolith, cast-to-shape in a microchannel. The polymer monolith, produced by a phase separation process, is capable of trapping and retaining charged protein species from a mixture of charged and uncharged species under the influence of an applied electric field. The retained charged protein species are released from the porous polymer monolith by a pressure driven flow in the substantial absence of the electric field. The pressure driven flow is independent of direction and thus neither means to reverse fluid flow nor a multi-directional flow field is required, a single flow through the porous polymer monolith can be employed, in contrast to prior art systems. The monolithic polymer material produced by the invention can function as a chromatographic medium. Moreover, by virtue of its ability to retain charged protein species and quantitatively release the retained species the porous polymer monolith can serve as a means for concentrating charged protein species from, for example, a dilute solution.

Shepodd, Timothy J. (Livermore, CA); Franklin, Elizabeth (Rolla, MO); Prickett, Zane T. (Golden, CO); Artau, Alexander (Pleasanton, CA)

2006-05-30

466

Non-equilibrium behavior of spin-cast films  

NASA Astrophysics Data System (ADS)

The behavior of polystyrene films cast from various solvents using an electric field to weakly perturb the free surface of the polymer melt was examined. The effective viscosity and residual stresses of the as-spun films strongly depend on the casting solvent. As-cast films had a substantially reduced viscosity compared to annealed films, with the greatest reduction in films cast from solutions near ?-temperature. The reduced viscosity is explained in terms of non-equilibrium effects from the film formation process; rapid quenching during spin-coating results in a lower entanglement density of chains compared to an equilibrium melt. The difference in films spun from the various solvents is explained by changes in chain conformations in the initial solutions and the vitrification point. The wavelength of the instabilities in as-cast films was higher than expected, indicating a weak stabilizing pressure. This is attributed to frozen-in normal stresses resulting from an asymmetric deformation of the chains due to evaporation of residual solvent after vitrification. The results show the non-equilibrium nature of as-cast polymer films and that processing conditions strongly influence their behavior.

Thomas, Katherine

2011-03-01

467

Mechanical properties and microstructure of centrifugally cast alloy 718  

SciTech Connect

The relationship between the microstructure and mechanical properties of alloy 718 was investigate for two discs centrifugally cast at 50 and 200 rpm and given a duplex age heat treatment. The results of mechanical property tests at temperatures from 426 to 649/sup 0/C showed that the tensile, yield and ultimate strength levels of both castings were similar. However, the creep-rupture properties were considerably enhanced for the casting produced at 200 rpm. Comparison of the radial and transverse creep properties of each disc indicated that creep life was generally independent of orientation, but ductility was greatest for specimens oriented transverse to the radial direction of the casting. Fatigue crack propagation performance was not greatly influenced by orientation or mold speed parameters and is comparable to wrought alloy 718 when compared on the basis of stress intensity factor range. The centrifugal casting process was found to produce a homogeneous microstructure free of porosity but with the expected segregation of solute alloying elements to Laves and carbide phases. The effect of the as-cast microstructure on the mechanical behavior and the potential influence of hot isostatic pressing to improve the microstructure are discussed.

Michel, D.J.; Smith, H.H.

1985-07-01

468

Mechanical properties and microstructure of centrifugally cast alloy 718  

NASA Astrophysics Data System (ADS)

The relationship between the microstructure and mechanical properties of alloy 718 was investigated for two discs centrifugally cast at 50 and 200 rpm and given a duplex age heat treatment. The results of mechanical property tests at temperatures from 426 to 649 °C showed that the tensile yield and ultimate strength levels of both castings were similar. However, the creep-rupture properties were considerably enhanced for the casting produced at 200 rpm. Comparison of the radial and transverse creep properties of each disc indicated that creep life was generally independent of orientation, but ductility was greatest for specimens oriented transverse to the radial direction of the casting. Fatigue crack propagation performance was not greatly influenced by orientation or mold speed parameters and was comparable to wrought alloy 718 when compared on the basis of stress intensity factor range. The centrifugal casting process was found to produce a homogeneous microstructure free of porosity but with the expected segregation of solute alloying elements to Laves and carbide phases. The effect of the as-cast microstructure on the mechanical behavior and the potential influence of hot isostatic pressing to improve the microstructure are discussed.

Michel, D. J.; Smith, H. H.

1985-07-01

469

Effects of Pouring Temperature and Squeeze Pressure on Al8%Si Alloy Squeeze Cast Parts  

Microsoft Academic Search

This study investigated the effects of squeeze parameters on the properties of squeeze castings and the optimum parameters for producing squeeze castings from Al-Si alloy. It also compared the properties of the squeeze castings with those of chill castings. Squeeze castings were made from Al-8%Si alloy using pressures of 25- 150MPa with the alloy poured at 650o, 700o and 750oC

A. Raji; R. H. Khan

470

Materials processing threshold report: 2. Use of low gravity for cast iron process development  

NASA Technical Reports Server (NTRS)

Potential applications of a low gravity environment of interest to the commercial producers of cast iron were assessed to determine whether low gravity conditions offer potential opportunities to producers for improving cast iron properties and expanding the use of cast irons. The assessment is limited to the gray and nodular types of iron, however, the findings are applicable to all cast irons. The potential advantages accrued through low gravity experiments with cast irons are described.

Frankhouser, W. L.

1980-01-01

471

A level set based method for the optimization of cast part  

Microsoft Academic Search

A cast part is formed via casting process in which molten liquid is poured into and solidifies in a cavity enclosed by molds.\\u000a Then, one obtains the cast part when the molds are removed. An important issue in the casting process is that a cast part\\u000a should have a proper geometry so that the molds can actually be removed. Accordingly,

Qi Xia; Tielin Shi; Michael Yu Wang; Shiyuan Liu

2010-01-01

472

Letter Report: LAW Simulant Development for Cast Stone Screening Test  

SciTech Connect

More than 56 million gallons of radioactive and hazardous waste are stored in 177 underground storage tanks at the U.S. Department of Energy’s (DOE’s) Hanford Site in southeastern Washington State. The Hanford Tank Waste Treatment and Immobilization Plant (WTP) is being constructed to treat the wastes and immobilize them in a glass waste form. The WTP includes a pretreatment facility to separate the wastes into a small volume of high-level waste (HLW) containing most of the radioactivity and a larger volume of low-activity waste (LAW) containing most of the nonradioactive chemicals. The HLW will be converted to glass in the HLW vitrification facility for ultimate disposal at an offsite federal repository. At least a portion (~35%) of the LAW will be converted to glass in the LAW vitrification facility and will be disposed of onsite at the Integrated Disposal Facility (IDF). The pretreatment and HLW vitrification facilities will have the capacity to treat and immobilize the wastes destined for each facility. However, a second facility will be needed for the expected volume of additional LAW requiring immobilization. A cementitious waste form known as Cast Stone is being considered to provide the required additional LAW immobilization capacity. The Cast Stone waste form must be acceptable for disposal in the IDF. The Cast Stone waste form and immobilization process must be tested to demonstrate that the final Cast Stone waste form can comply with waste acceptance criteria for the IDF disposal facility and that the immobilization processes can be controlled to consistently provide an acceptable waste form product. Further, the waste form must be tested to provide the technical basis for understanding the long term performance of the waste form in the IDF disposal environment. These waste form performance data are needed to support risk assessment and performance assessment (PA) analyses of the long-term environmental impact of the waste disposal in the IDF. A testing program was developed in fiscal year (FY) 2012 describing in some detail the work needed to develop and qualify Cast Stone as a waste form for the solidification of Hanford LAW (Westsik et al. 2012). Included within Westsik et al. (2012) is a section on the near-term needs to address Tri-Party Agreement Milestone M-062-40ZZ. The objectives of the testing program to be conducted in FY 2013 and FY 2014 are to: • Determine an acceptable formulation for the LAW Cast Stone waste form. • Evaluate sources of dry materials for preparing the LAW Cast Stone. • Demonstrate the robustness of the Cast Stone waste form for a range of LAW compositions. • Demonstrate the robustness of the formulation for variability in the Cast Stone process. • Provide Cast Stone contaminant release data for PA and risk assessment evaluations. The first step in determining an acceptable formulation for the LAW Cast Stone waste form is to conduct screening tests to examine expected ranges in pretreated LAW composition, waste stream concentrations, dry-materials sources, and mix ratios of waste feed to dry blend. A statistically designed test matrix will be used to evaluate the effects of these key parameters on the properties of the Cast Stone as it is initially prepared and after curing. The second phase of testing will focus on selection of a baseline Cast Stone formulation for LAW and demonstrating that Cast Stone can meet expected waste form requirements for disposal in the IDF. It is expected that this testing will use the results of the screening tests to define a smaller suite of tests to refine the composition of the baseline Cast Stone formulation (e.g. waste concentration, water to dry mix ratio, waste loading).

Russell, Renee L.; Westsik, Joseph H.; Swanberg, David J.; Eibling, Russell E.; Cozzi, Alex; Lindberg, Michael J.; Josephson, Gary B.; Rinehart, Donald E.

2013-03-27

473

Dependence of interfacial heat transfer coefficient on casting surface temperature during solidification of Al-Si alloy castings cast in CO2 sand mold  

NASA Astrophysics Data System (ADS)

Interfacial heat transfer coefficient at the metal-mold interface (IHTC) was estimated by an iterative algorithm based on the function specification method. An Al-9 wt% Si alloy plate casting was made in a sand mold prepared by CO2 process. Thermal history obtained from the experiment was used to solve an inverse heat conduction problem. Acquired transient IHTC values are then given in function of the casting surface temperature at the interface. By comparing the obtained results with previous findings, the influence of grain fineness number and consequently of mold roughness on maximum IHTC values is revealed.

Kova?evi?, Lazar; Terek, Pal; Mileti?, Aleksandar; Kakaš, Damir

2014-03-01

474

Microstructure and fatigue characteristics of direct chill cast and electromagnetic cast 2024 Al alloy ingots  

NASA Astrophysics Data System (ADS)

The distinct advantages of the electromagnetic casting (EMC) process consist in the presence of stirring motions in the melt, which lead to significant grain size reduction in solidified ingot. Furthermore, surface and subsurface qualities are improved due to the absence of ingot mold. However, it is impossible to achieve the aforementioned advantages in conventional direct chill casting (DCC). In order to contrast the before and after heat treatments of the microstructural and mechanical characteristics of EMC and DCC 2024 aluminium alloys, optical microscopy, scanning electron microscopy, transmission electron microscopy (TEM), X-ray diffractions (XRD), differential scanning calorimetry (DSC), etc. were carried out. Compared with the DCC ingot, the EMC ingot has better mechanical properties not only in the ascast condition but also in the as-aged condition. The DSC curves show that the EMC specimens have high enthalpy, i.e., the thermal kinetic energy to form precipitates during the aging treatment process. Despite heat treatments applied to the DCC ingot, it fails to attain the same mechanical properties as the EMC ingot. Moreover, considering the expernsive scalping operation for DCC ingots, the EMC technique, which offers a lower manufacturing cost, is one of the best manufacturing methods used in obtaining the ingots of wrought aluminum alloys.

Kim, Sug Won; Hao, Hai

2003-07-01

475

A comparative characterization of near-equiaxed microstructures as produced by spray casting, magnetohydrodynamic casting and the stress induced, melt activated process  

Microsoft Academic Search

The near-equiaxed microstructure of wrought and cast aluminum alloys as produced by the most common methods used to provide material for subsequent semisolid processing, is examined. More specifically, the grain size and degree of spheroidization of alloys produced by spray casting, magnetohydrodynamic (MHD) casting and the stress induced, melt activated (SIMA) process are characterized and compared. It is shown that

Evangelos Tzimas; Antonios Zavaliangos

2000-01-01

476

Macrovoid Defect Growth during Evaporative Casting of Polymeric Membranes  

NASA Technical Reports Server (NTRS)

Macrovoid (MV) formation is a significant problem in evaporatively cast polymeric membranes. MVs are large, elongated or teardrop-shaped pores (10-50 micron) that can impair membrane structural integrity. Although MVs have been extensively studied, there is no general agreement on the mechanisms governing MV growth. Recently, our research group has formulated the solutocapillary convection (SC) hypothesis, which contends that MV growth involves three principal forces: a Marangoni force generated by surface tension gradients within the MV interface, a viscous drag force, and a gravitationally induced body force. Two sets of complementary experiments were conducted to test the SC hypothesis. Ground-based videomicroscopy flow-visualization (VMFV) was utilized to measure the flow velocities at the MV-casting solution interface and deep within the casting solution. The measurements were performed with casting solutions containing 10 wt% cellulose acetate (CA), 30 wt% H2O, 60 wt% acetone, and 200- ppm TiO2 particles for flow visualization, and the surface tension was controlled by surfactant addition. Qualitatively, the experiments indicated that MV growth occurs in three distinct phases: (1) a very rapid initial growth period, (2) a much slower growth phase, and (3) absorption of selected MVs into the expanding demixed region. The presence of tracer particles inside the MVs suggests the presence of a convective flow, which transfers the particles from the bulk solution to the MV interior. Although the VMFV experiments did not establish any surfactant effect on the interfacial velocities, a statistically significant effect on the MV number density was observed. In the second set of experiments, membranes were cast aboard a KC-135 aircraft under 0-g and 2-g conditions. Despite careful attention to the design and fabrication of the membrane casting apparatus (MCA), several problems were encountered, the most significant of which was the contamination of the casting solution by the activated carbon particles used for solvent absorption.

Greenberg, A. R.; Khare, V. P.; Zartman, J.; Krantz, W. B.; Todd, P.

2003-01-01

477

Secondary Waste Cast Stone Waste Form Qualification Testing Plan  

SciTech Connect

The Hanford Tank Waste Treatment and Immobilization Plant (WTP) is being constructed to treat the 56 million gallons of radioactive waste stored in 177 underground tanks at the Hanford Site. The WTP includes a pretreatment facility to separate the wastes into high-level waste (HLW) and low-activity waste (LAW) fractions for vitrification and disposal. The LAW will be converted to glass for final disposal at the Integrated Disposal Facility (IDF). Cast Stone – a cementitious waste form, has been selected for solidification of this secondary waste stream after treatment in the ETF. The secondary-waste Cast Stone waste form must be acceptable for disposal in the IDF. This secondary waste Cast Stone waste form qualification testing plan outlines the testing of the waste form and immobilization process to demonstrate that the Cast Stone waste form can comply with the disposal requirements. Specifications for the secondary-waste Cast Stone waste form have not been established. For this testing plan, Cast Stone specifications are derived from specifications for the immobilized LAW glass in the WTP contract, the waste acceptance criteria for the IDF, and the waste acceptance criteria in the IDF Permit issued by the State of Washington. This testing plan outlines the testing needed to demonstrate that the waste form can comply with these waste form specifications and acceptance criteria. The testing program must also demonstrate that the immobilization process can be controlled to consistently provide an acceptable waste form product. This testing plan also outlines the testing needed to provide the technical basis for understanding the long-term performance of the waste form in the disposal environment. These waste form performance data are needed to support performance assessment analyses of the long-term environmental impact of the secondary-waste Cast Stone waste form in the IDF

Westsik, Joseph H.; Serne, R. Jeffrey

2012-09-26

478

Application of particle method to the casting process simulation  

NASA Astrophysics Data System (ADS)

Casting processes involve many significant phenomena such as fluid flow, solidification, and deformation, and it is known that casting defects are strongly influenced by the phenomena. However the phenomena complexly interacts each other and it is difficult to observe them directly because the temperature of the melt and other apparatus components are quite high, and they are generally opaque; therefore, a computer simulation is expected to serve a lot of benefits to consider what happens in the processes. Recently, a particle method, which is one of fully Lagrangian methods, has attracted considerable attention. The particle methods based on Lagrangian methods involving no calculation lattice have been developed rapidly because of their applicability to multi-physics problems. In this study, we combined the fluid flow, heat transfer and solidification simulation programs, and tried to simulate various casting processes such as continuous casting, centrifugal casting and ingot making. As a result of continuous casting simulation, the powder flow could be calculated as well as the melt flow, and the subsequent shape of interface between the melt and the powder was calculated. In the centrifugal casting simulation, the mold was smoothly modeled along the shape of the real mold, and the fluid flow and the rotating mold are simulated directly. As a result, the flow of the melt dragged by the rotating mold was calculated well. The eccentric rotation and the influence of Coriolis force were also reproduced directly and naturally. For ingot making simulation, a shrinkage formation behavior was calculated and the shape of the shrinkage agreed well with the experimental result.

Hirata, N.; Zulaida, Y. M.; Anzai, K.

2012-07-01

479

An association between the Calpastatin (CAST) gene and keratoconus  

PubMed Central

Purpose Keratoconus is a genetically heterogeneous corneal dystrophy. Previously, we performed two genome-wide linkage scans in a four generation autosomal dominant pedigree and repeatedly mapped a keratoconus locus to a genomic region located on chromosome 5q overlapping the gene encoding the inhibitor of calpains, calpastatin (CAST). To test whether variants in CAST gene are involved in genetic susceptibility to keratoconus we performed genetic testing of polymorphic markers in CAST gene in family and case-control panels of patients with keratoconus. Methods We genotyped SNPs (Single Nucleotide Polymorphisms) located in CAST gene in 262 patients in 40 Caucasian keratoconus families and in a Caucasian case-control panel with 304 cases and 518 controls. Generalized estimating equation models accounting for familial correlations implemented in GWAF program were used for association testing in families. Logistic regression models implemented in PLINK were performed to test associations in case-control samples. Results Genetic testing of first set of seven SNPs in familial samples revealed two tentative nominally significant markers (rs4869307 p=0.03; rs27654: p=0.07). Additional genotyping of twelve tightly spaced SNPs identified CAST SNP rs4434401 to be associated with keratoconus in both familial and case-control panels with p values of 0.005 and 0.05, respectively; and with combined meta p value of familial and case-control cohorts of 0.002, or, after Bonferroni correction, 0.04. Conclusions Linkage analysis and genetic association support involvement of CAST gene in the genetic susceptibility to keratoconus. In-silico analysis of CAST expression suggests differential regulation of calpain/calpastatin system in cornea as a potential mechanism of functional defect.

Li, Xiaohui; Bykhovskaya, Yelena; Tang, Yongming G.; Picornell, Yoana; Haritunians, Talin; Aldave, Anthony J.; Szczotka-Flynn, Loretta; Iyengar, Sudha K.; Rotter, Jerome I.; Taylor, Kent D.; Rabinowitz, Yaron S.

2013-01-01

480

Simulation and Experiment on Direct Continuous Casting Process of Lead Frame Copper Alloy  

SciTech Connect

Direct Continuous Casting (D.C.C) is an important method in casting lead frame copper alloy. In this paper, numerical simulation is adopted to investigate the casting process in order to optimize the D.C.C technical parameters, such as the casting temperature, casting speed and cooling intensity. According to the numerical results, the reasonable parameters are that the casting temperature is between 1413 Kapprox1413 K, the casting speed is between 8 m/happrox10 m/h and the speed of cooling water is between 4.2 m/sapprox4.6 m/s. And the depth of liquid-solid boundary is measured in different casting temperature and casting speed by experiments. The results show the actual measurements have a little deviation with the numerical simulation. The results of numerical simulation provide the significant reference to the actual experiments.

Huang Guojie; Xie Shuisheng; Cheng Lei [State Key Laboratory for Fabrication and Process of Nonferrous Metals, Beijing General Research Institute for Non-ferrous Metals, 100088 (China)

2010-06-15

481

Simulation and Experiment on Direct Continuous Casting Process of Lead Frame Copper Alloy  

NASA Astrophysics Data System (ADS)

Direct Continuous Casting (D.C.C) is an important method in casting lead frame copper alloy. In this paper, numerical simulation is adopted to investigate the casting process in order to optimize the D.C.C technical parameters, such as the casting temperature, casting speed and cooling intensity. According to the numerical results, the reasonable parameters are that the casting temperature is between 1413 K~1413 K, the casting speed is between 8 m/h~10 m/h and the speed of cooling water is between 4.2 m/s~4.6 m/s. And the depth of liquid-solid boundary is measured in different casting temperature and casting speed by experiments. The results show the actual measurements have a little deviation with the numerical simulation. The results of numerical simulation provide the significant reference to the actual experiments.

Guojie, Huang; Shuisheng, Xie; Lei, Cheng

2010-06-01

482

Method of reducing the green density of a slip cast article  

DOEpatents

The method disclosed in this specification is one of reducing the green density of an article cast in a slip casting operation. The article is cast from a casting slip containing silicon metal particles, yttrium containing particles, and a small amount of a fluoride salt which is effective to suppress flocculation of the silicon metal particles by y.sup.+3 ions derived from the yttrium containing particles. The method is characterized by the following step. A small amount of compound which produces a cation which will partly flocculate the particles of silicon metal is added to the casting slip. The small amount of this compound is added so that when the casting slip is slip cast into a casting mold, the partly flocculated particles of silicon will interrupt an otherwise orderly packing of the particles of silicon and particles of yttrium. In this manner, the green density of the slip cast article is reduced and the article may be more easily nitrided.

Mangels, John A. (Flat Rock, MI); Dickie, Ray A. (Birmingham, MI)

1985-01-01

483

Treatment of acute kidney injury with cast nephropathy.  

PubMed

Nearly 50% of patients with multiple myeloma develop renal disease; acute kidney injury (AKI) from cast nephropathy, or "myeloma kidney" is the most common type. Development of AKI is associated with worse 1-year survival and reduces the therapeutic options available to patients. Therefore, there is a great need to develop more effective therapies. Cast nephropathy is due to the interaction and aggregation of filtered free light chains (FLCs) and Tamm- Horsfall protein (THP) causing intratubular obstruction and damage. The key to treating cast nephropathy is rapid lowering of FLCs as this correlates with renal recovery. Newer chemotherapy agents lower FLCs and have been referred to as "renoprotective". However there remains great interest in using various extracorporeal therapies to remove serum FLCs. Initially, therapeutic plasma exchange (TPE) was thought to improve renal outcomes in cast nephropathy based on small trials. The largest randomized trial of TPE, however, failed to show any benefit. A newer technique is extended high cut-off hemodialysis (HCO-HD). This modality uses a high molecular weight cut-off filter to remove FLCs. To date, trials with HCO-HD in patients with cast nephropathy have been encouraging. However, there are no randomized trials demonstrating the benefit of HCOHD when used in addition to newer chemotherapeutic regimens. Until these studies are available, HCO-HD cannot be recommended as standard of care. PMID:24725380

Walther, Carl; Podoll, Amber S; Finkel, Kevin W

2014-07-01

484

Computational algorithms to simulate the steel continuous casting  

NASA Astrophysics Data System (ADS)

Computational simulation is a very powerful tool to analyze industrial processes to reduce operating risks and improve profits from equipment. The present work describes the development of some computational algorithms based on the numerical method to create a simulator for the continuous casting process, which is the most popular method to produce steel products for metallurgical industries. The kinematics of industrial processing was computationally reproduced using subroutines logically programmed. The cast steel by each strand was calculated using an iterative method nested in the main loop. The process was repeated at each time step (? t) to calculate the casting time, simultaneously, the steel billets produced were counted and stored. The subroutines were used for creating a computational representation of a continuous casting plant (CCP) and displaying the simulation of the steel displacement through the CCP. These algorithms have been developed to create a simulator using the programming language C++. Algorithms for computer animation of the continuous casting process were created using a graphical user interface (GUI). Finally, the simulator functionality was shown and validated by comparing with the industrial information of the steel production of three casters.

Ramírez-López, A.; Soto-Cortés, G.; Palomar-Pardavé, M.; Romero-Romo, M. A.; Aguilar-López, R.

2010-10-01

485

High strength cast aluminum alloy development  

NASA Astrophysics Data System (ADS)

The goal of this research was to understand how chemistry and processing affect the resulting microstructure and mechanical properties of high strength cast aluminum alloys. Two alloy systems were investigated including the Al-Cu-Ag and the Al-Zn-Mg-Cu systems. Processing variables included solidification under pressure (SUP) and heat treatment. This research determined the range in properties that can be achieved in BAC 100(TM) (Al-Cu micro-alloyed with Ag, Mn, Zr, and V) and generated sufficient property data for design purposes. Tensile, stress corrosion cracking, and fatigue testing were performed. CuAl2 and Al-Cu-Fe-Mn intermetallics were identified as the ductility limiting flaws. A solution treatment of 75 hours or longer was needed to dissolve most of the intermetallic CuAl 2. The Al-Cu-Fe-Mn intermetallic was unaffected by heat treatment. These results indicate that faster cooling rates, a reduction in copper concentration and a reduction in iron concentration might increase the ductility of the alloy by decreasing the size and amount of the intermetallics that form during solidification. Six experimental Al-Zn-Mg-Cu series alloys were produced. Zinc concentrations of 8 and 12wt% and Zn/Mg ratios of 1.5 to 5.5 were tested. Copper was held constant at 0.9%. Heat treating of the alloys was optimized for maximum hardness. Al-Zn-Mg-Cu samples were solution treated at 441°C (826°F) for 4 hours before ramping to 460°C (860°F) for 75 hours and then aged at 120°C (248°F) for 75 hours. X-ray diffraction showed that the age hardening precipitates in most of these alloys was the T phase (Mg32Zn 31.9Al17.1). Tensile testing of the alloys showed that the best mechanical properties were obtained in the lowest alloy condition. Chilled Al-8.2Zn-1.4Mg-0.9Cu solidified under pressure resulted in an alloy with a yield strength of 468MPa (68ksi), tensile strength of 525MPa (76ksi) and an elongation of 9%.

Druschitz, Edward A.

486

Casting behavior and tensile strength of cast BaTiO sub 3 tape  

SciTech Connect

The casting behavior and properties of thin, unsintered BaTiO{sub 3} tapes were studied by measuring viscosity of the slip, green density, ultimate tensile stress, and strain to failure. It was found that increasing the binder to plasticizer ratio increased slip viscosity and strength as expected but also increased strain to failure, and that increasing the poly(ethylene glycol) to benzyl butyl phthalate ratio improved tape release and tape strength, but a small amount of benzyl butyl phthalate improved strain to failure. In addition, increasing the powder to organics ratio increased slip viscosity and green density but strength passed through a maximum and strain to failure decreased. Both slip viscosity and green density were optimized at a particular dispersant concentration but strength decreased monotonically with increased dispersant addition. Finally, an optimum cyclohexanone addition led to a maximum density and strength.

Karas, A.; Kumagai, Toshiya; Cannon, W.R. (Rutgers, The State Univ. of New Jersey, Piscataway (USA))

1988-07-01

487

Estimation of Volume Deficit Characteristic of Cast Al-Si-Mg Alloy  

NASA Astrophysics Data System (ADS)

Volume deficit characteristic of US A356 cast aluminium alloy has been discussed in the present study. The reduction in specific volume leads to volume deficit in castings and it can be visualized as a casting defect. The information regarding the volume deficit and its distribution is essential in minimizing casting defects. The volume deficit can be classified as macro cavities, internal porosity, surface sinks and volumetric contraction. These defects are measured using mathematical formulae and the actual volume deficit of the given casting has been arrived by adding all the defects. Influence of bottom chill and casting shape on the volume deficit characteristics have been studied.

Santhi, S.; Sakri, S. B.; Rao, D. Hanumantha; Sundarrajan, S.

2013-04-01

488

Effect of Process Parameters, Casting Thickness, and Alloys on the Interfacial Heat-Transfer Coefficient in the High-Pressure Die-Casting Process  

NASA Astrophysics Data System (ADS)

The heat transfer at the metal-die interface is believed to have great influence on the solidification process and cast structure of the high-pressure die-casting (HPDC) process. The present article focused on the effects of process parameters, casting thickness, and alloys on the metal-die interfacial heat-transfer coefficient (IHTC) in the HPDC process. Experiment was carried out on a cold-chamber die-casting machine with two casting alloys AM50 and ADC12. A special casting, namely, “step-shape” casting, was used and cast against a H13 steel die. The IHTC was determined using an inverse approach based on the temperature measurements inside the die. Results show that the IHTC is different at different steps and changes as the solidification of the casting proceeds. Process parameters only influence the IHTC in its peak value, and for both AM50 and ADC12 alloys, a greater fast shot velocity leads to a greater IHTC peak value at steps 1 and 2. The initial die surface temperature has a more prominent influence on the IHTC peak values at the thicker steps, especially step 5. Results also show that a closer contact between the casting and die could be achieved when the casting alloy is ADC12 instead of AM50, which consequently leads to a higher IHTC.

Guo, Zhi-Peng; Xiong, Shou-Mei; Liu, Bai-Cheng; Li, Mei; Allison, John

2008-12-01

489

Nondestructive characterization of ductile cast iron by magnetic adaptive testing  

NASA Astrophysics Data System (ADS)

This paper reports correlation of magnetic descriptors with Brinell hardness and conductivity of ductile cast iron, aiming to develop a novel nondestructive method by magnetic adaptive testing. Four series of cast iron staircase-shaped samples were investigated by this method, where different cooling rates of samples during casting resulted in different structures of each sample. The flat samples were magnetized by an attached yoke, and sensitive descriptors were obtained from a proper evaluation, based on the measurements of series of magnetic minor hysteresis loops, without magnetic saturation of the samples. Results of the nondestructive magnetic tests were compared with destructive mechanical measurements of Brinell hardness and conductivity and good correlation was found between them.

Vertesy, G.; Uchimoto, T.; Tomáš, I.; Takagi, T.

2010-10-01

490

Fabrication of cast particle-reinforced metals via pressure infiltration  

NASA Technical Reports Server (NTRS)

A new casting process for fabrication of particle-reinforced metals is presented whereby a composite of particulate reinforcing phase in metal is first produced by pressure infiltration. This composite is then diluted in additional molten metal to obtain the desired reinforcement volume fraction and metal composition. This process produces a pore-free as-cast particulate metal-matrix composite. This process is demonstrated for fabrication of magnesium-matrix composites containing SiC reinforcements of average diameter 30, 10 and 3 microns. It is compared with the compocasting process, which was investigated as well for similar SiC particles in Mg-10 wt pct Al, and resulted in unacceptable levels of porosity in the as-cast composite.

Klier, E. M.; Mortensen, A.; Cornie, J. A.; Flemings, M. C.

1991-01-01

491

[The clinical application of Vitallium 2000 casting removable partial denture].  

PubMed

The casting removable partial denture (RPD) is one of most commonly prosthesis methods in present. Vitallium is one kind of dental alloy with cobalt, chromium and molybdenum etc. It has three ranks respectively: Vitallium, Vitallium 2000 and Vitallium 2000 plus. Although the traditional casting RPD are commonly used, but it has been limited in the physical capabilities of traditional dental alloy. It would not been done to flexible design on denture especially on denture base. The elasticity of casting clasp is not good, the volume is thick. Because of the Vickers hardness and elongation of Vitallium 2000 and Vitallium 2000 plus are better than traditional dental alloys, so the RPD with Vitallium 2000 has good bending control, deformation rebound and fracture resistance. The benefit of Vitallium 2000 or Vitallium 2000 plus is the RPD with splitting can be designed for some free end clinical cases, to solve some clinical problems. PMID:19472868

Sun, Feng

2009-04-01

492

Development of a CFD code for casting simulation  

NASA Technical Reports Server (NTRS)

The task of developing a computational fluid dynamics (CFD) code to accurately model the mold filling phase of a casting operation was accomplished in a systematic manner. First the state-of-the-art was determined through a literature search, a code search, and participation with casting industry personnel involved in consortium startups. From this material and inputs from industry personnel, an evaluation of the currently available codes was made. It was determined that a few of the codes already contained sophisticated CFD algorithms and further validation of one of these codes could preclude the development of a new CFD code for this purpose. With industry concurrence, ProCAST was chosen for further evaluation. Two benchmark cases were used to evaluate the code's performance using a Silicon Graphics Personal Iris system. The results of these limited evaluations (because of machine and time constraints) are presented along with discussions of possible improvements and recommendations for further evaluation.

Murph, Jesse E.

1992-01-01

493

Esthetic modification of cast dental-ceramic restorations.  

PubMed

The advantages and disadvantages of conventional opaque substructures (eg, metal ceramic restorations) used for creating esthetic complete crown restorations are reviewed, and the esthetic advantages of veneering a translucent crown (Dicor) are considered. An appropriate aluminous veneering porcelain was identified (Vitadur Veneer). This veneer porcelain was chosen to match the thermal coefficient of expansion of the cast glass-ceramic substructure. A flexural strength study was then completed and it showed no difference in the strength of the veneered and nonveneered translucent cast glass-ceramic specimens. Scanning electron microscopy revealed that the interface between the porcelain veneer and cast glass-ceramic substructure had no visible porosity and resulted in a continuous-appearing structure. Potential coping designs, as well as the clinical applications and ramifications of this modified crown, are discussed. PMID:2133378

Campbell, S D

1990-01-01

494

Method and apparatus for casting conductive and semiconductive materials  

DOEpatents

A method and apparatus is disclosed for casting conductive and semiconduce materials. The apparatus includes a plurality of conductive members arranged to define a container-like area having a desired cross-sectional shape. A portion or all of the conductive or semiconductive material which is to be cast is introduced into the container-like area. A means is provided for inducing the flow of an electrical current in each of the conductive members, which currents act collectively to induce a current flow in the material. The induced current flow through the conductive members is in a direction substantially opposite to the induced current flow in the material so that the material is repelled from the conductive members during the casting process.

Ciszek, Theodore F. (Evergreen, CO) [Evergreen, CO

1986-01-01