WorldWideScience

Sample records for castings

  1. Caste System

    OpenAIRE

    Hoff, Karla

    2016-01-01

    In standard economics, individuals are rational actors and economic forces undermine institutions that impose large inefficiencies. The persistence of the caste system is evidence of the need for psychologically more realistic models of decision-making in economics. The caste system divides South Asian society into hereditary groups whose lowest ranks are represented as innately polluted. ...

  2. Solidification and casting

    CERN Document Server

    Cantor, Brian

    2002-01-01

    INDUSTRIAL PERSPECTIVEDirect chillcasting of aluminium alloysContinuous casting of aluminium alloysContinuous casting of steelsCastings in the automotive industryCast aluminium-silicon piston alloysMODELLING AND SIMULATIONModelling direct chill castingMold filling simulation of die castingThe ten casting rulesGrain selection in single crystal superalloy castingsDefects in aluminium shape castingPattern formation during solidificationPeritectic solidificationSTRUCTURE AND DEFECTSHetergeneous nucleation in aluminium alloysCo

  3. Nodular cast iron and casting monitoring

    Directory of Open Access Journals (Sweden)

    S. Pietrowski

    2008-10-01

    Full Text Available In this paper quality monitoring of nodular cast iron and casting made of it is presented. A control system of initial liquid cast iron to spheroidization, after spheroidization and inoculation with using of TDA method was shown. An application of an ultrasonic method to assessment of the graphite form and the metal matrix microstructure of castings was investigated.

  4. Nodular cast iron and casting monitoring

    OpenAIRE

    2008-01-01

    In this paper quality monitoring of nodular cast iron and casting made of it is presented. A control system of initial liquid cast iron to spheroidization, after spheroidization and inoculation with using of TDA method was shown. An application of an ultrasonic method to assessment of the graphite form and the metal matrix microstructure of castings was investigated.

  5. Casting materials

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-06-14

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

  6. The UK Casting Industry

    Institute of Scientific and Technical Information of China (English)

    Jincheng Liu

    2006-01-01

    The casting production in the UK in 2004 is presented and analysed. The UK casting industry has played an important role in world casting and manufacturing production. However recent years the rapid development of some developing countries has been shifting the casting production from the western industrialized countries including the UK. The UK casting industry and associated research and technology organizations, universities have been working together very hard to face the serious competition to make the UK casting industry have a sustainable future. The UK casting industry remains strong and plays an important role in world casting and manufacturing production.

  7. CA Investment Casting Process of Complex Castings

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    CA (Computer aided) investment casting technique used in superalloy castings of aerospace engine parts was presented. CA investment casting integrated computer application, RP (Rapid Prototyping) process, solidification simulation and investment casting process. It broke the bottle neck of making metal die. Solid model of complex parts were produced by UGII or other software, then translated into STL(Stereolithography) file, after RP process of SLS(Selective Laser Sintering), wax pattern used in investment ...

  8. Cast irons

    CERN Document Server

    1996-01-01

    Cast iron offers the design engineer a low-cost, high-strength material that can be easily melted and poured into a wide variety of useful, and sometimes complex, shapes. This latest handbook from ASM covers the entire spectrum of one of the most widely used and versatile of all engineered materials. The reader will find the basic, but vital, information on metallurgy, solidification characteristics, and properties. Extensive reviews are presented on the low-alloy gray, ductile, compacted graphite, and malleable irons. New and expanded material has been added covering high-alloy white irons used for abrasion resistance and high-alloy graphitic irons for heat and corrosion resistance. Also discussed are melting furnaces and foundry practices such as melting, inoculation, alloying, pouring, gating and rising, and molding. Heat treating practices including stress relieving, annealing, normalizing, hardening and tempering, autempering (of ductile irons), and surface-hardening treatments are covered, too. ASM Spec...

  9. The ancient Chinese casting techniques

    OpenAIRE

    2011-01-01

    In the course of Chinese civilization, which lasted more than 5,000 years, casting production has made a huge contribution. In this paper, some representative metal castings were presented. According to their forming techniques, they can be grouped into stone mould casting, clay mould casting, ablation casting, lost wax casting, stack casting, permanent mould casting, sand casting, etc. According to their materials, they can be categorized into tin bronze, bimetallic bronze, malleable cast ir...

  10. Thin Wall Iron Castings

    Energy Technology Data Exchange (ETDEWEB)

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

    2001-10-31

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

  11. LLNL casting technology

    Science.gov (United States)

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

    1994-01-01

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

  12. Glovebox Advanced Casting System Casting Optimization

    Energy Technology Data Exchange (ETDEWEB)

    Fielding, Randall Sidney [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-03-01

    Casting optimization in the GACS included three broad areas; casting of U-10Zr pins, incorporation of an integral FCCI barrier, and development of a permanent crucible coating. U-10Zr casting was improved over last year’s results by modifying the crucible design to minimize contact with the colder mold. Through these modifications casting of a three pin batch was successful. Incorporation of an integral FCCI barrier also was optimized through furnace chamber pressure changes during the casting cycle to reduce gas pressures in the mold cavities which led to three full length pins being cast which incorporated FCCI barriers of three different thicknesses. Permanent crucible coatings were tested against a base case; 1500°C for 10 minutes in a U-20Pu-10Zr molten alloy. None of the candidate coating materials showed evidence of failure upon initial visual examination. In all areas of work a large amount of characterization will be needed to fully determine the effects of the optimization activities. The characterization activities and future work will occur next year.

  13. High integrity automotive castings

    Energy Technology Data Exchange (ETDEWEB)

    Weiss, D. [Eck Industries Inc., St. Manitowoc, WI (United States)

    2007-07-01

    This paper described the High Integrity Magnesium Automotive Casting (HI-MAC) program, which was developed to ensure the widespread adoption of magnesium in structural castings. The program will encourage the use of low pressure permanent molds, squeeze casting, and electromagnetic pumping of magnesium into dies. The HI-MAC program is currently investigating new heat treatment methods, and is in the process of creating improved fluid flow and solidification modelling to produce high volume automotive components. In order to address key technology barriers, the program has been divided into 8 tasks: (1) squeeze casting process development; (2) low pressure casting technology; (3) thermal treatment; (4) microstructure control; (5) computer modelling and properties; (6) controlled molten metal transfer and filling; (7) emerging casting technologies; and (8) technology transfer throughout the automotive value chain. Technical challenges were outlined for each of the tasks. 1 ref., 3 tabs., 5 figs.

  14. Evolution of halictine castes

    Science.gov (United States)

    Knerer, Gerd

    1980-03-01

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

  15. Caste in Itself, Caste and Class, or Caste in Class

    OpenAIRE

    Ramkrishna Mukherjee

    2015-01-01

    After the British conquered Bengal and eventually the whole of India,they set out to administer the colony. In this context they encountered two phenomena with which they were not familiar: (1) the relation of people to land for production (and not for revenue receiving, household living, etc.), and (2) the caste system of India, viz. the jati strati?cation of society.

  16. A cast orientation index.

    Science.gov (United States)

    Ivanhoe, J R; Mahanna, G K

    1994-12-01

    This article describes a technique that allows multiple master casts to be precisely oriented to the same path of insertion and withdrawal. This technique is useful in situations where multiple fixed prosthodontic preparations require surveyed restorations and a single master cast is not available.

  17. Higher Education's Caste System

    Science.gov (United States)

    Iannone, Ron

    2004-01-01

    In this article, the author discusses the history of the present caste system in higher education. He shows how the public's perception of this caste system is based on image and not usually on the quality of teaching and curriculum in colleges and universities. Finally, he discusses a model for accessibility to higher education and how higher…

  18. Caste and power

    DEFF Research Database (Denmark)

    Roy, Dayabati

    2011-01-01

    This paper explores the institution of caste and its operation in a micro-level village setting of West Bengal, an Indian state, where state politics at grass roots level is vibrant with functioning local self-government and entrenched political parties. This ethnographic study reveals that caste...

  19. Multi-layers castings

    Directory of Open Access Journals (Sweden)

    J. Szajnar

    2010-01-01

    Full Text Available In paper is presented the possibility of making of multi-layers cast steel castings in result of connection of casting and welding coating technologies. First layer was composite surface layer on the basis of Fe-Cr-C alloy, which was put directly in founding process of cast carbon steel 200–450 with use of preparation of mould cavity method. Second layer were padding welds, which were put with use of TIG – Tungsten Inert Gas surfacing by welding technology with filler on Ni matrix, Ni and Co matrix with wolfram carbides WC and on the basis on Fe-Cr-C alloy, which has the same chemical composition with alloy, which was used for making of composite surface layer. Usability for industrial applications of surface layers of castings were estimated by criterion of hardness and abrasive wear resistance of type metal-mineral.

  20. The ancient Chinese casting techniques

    Directory of Open Access Journals (Sweden)

    Tan Derui

    2011-02-01

    Full Text Available In the course of Chinese civilization, which lasted more than 5,000 years, casting production has made a huge contribution. In this paper, some representative metal castings were presented. According to their forming techniques, they can be grouped into stone mould casting, clay mould casting, ablation casting, lost wax casting, stack casting, permanent mould casting, sand casting, etc. According to their materials, they can be categorized into tin bronze, bimetallic bronze, malleable cast iron, ductile cast iron, brass, cupronickel alloy (Packtong, etc. According to their surface decorative techniques they can be devided into gem inlay, gilding, gold and silver inlay, copper inlay, engraved decoration, surface tin-enrichment, mother-of-pearl inlay, burnished works with gold or silver inlay, surface coloring and cloisonné enamel, etc.

  1. Caste in Itself, Caste and Class, or Caste in Class

    Directory of Open Access Journals (Sweden)

    Ramkrishna Mukherjee

    2015-08-01

    Full Text Available After the British conquered Bengal and eventually the whole of India,they set out to administer the colony. In this context they encountered two phenomena with which they were not familiar: (1 the relation of people to land for production (and not for revenue receiving, household living, etc., and (2 the caste system of India, viz. the jati strati?cation of society.

  2. Clean Metal Casting

    Energy Technology Data Exchange (ETDEWEB)

    Makhlouf M. Makhlouf; Diran Apelian

    2002-02-05

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

  3. Symptomatic stent cast.

    LENUS (Irish Health Repository)

    Keohane, John

    2012-02-03

    Biliary stent occlusion is a major complication of endoscopic stent insertion and results in repeat procedures. Various theories as to the etiology have been proposed, the most frequently studied is the attachment of gram negative bacteria within the stent. Several studies have shown prolongation of stent patency with antibiotic prophylaxis. We report the case of stent occlusion from a cast of a previously inserted straight biliary stent; a "stent cast" in an 86-year-old woman with obstructive jaundice. This was retrieved with the lithotrypter and she made an uneventful recovery. This is the first reported case of a biliary stent cast.

  4. Symptomatic stent cast.

    Science.gov (United States)

    Keohane, John; Moore, Michael; O'Mahony, Seamus; Crosbie, Orla

    2008-02-01

    Biliary stent occlusion is a major complication of endoscopic stent insertion and results in repeat procedures. Various theories as to the etiology have been proposed, the most frequently studied is the attachment of gram negative bacteria within the stent. Several studies have shown prolongation of stent patency with antibiotic prophylaxis. We report the case of stent occlusion from a cast of a previously inserted straight biliary stent; a "stent cast" in an 86-year-old woman with obstructive jaundice. This was retrieved with the lithotrypter and she made an uneventful recovery. This is the first reported case of a biliary stent cast.

  5. CENTRIFUGAL CASTING MACHINE

    Science.gov (United States)

    Shuck, A.B.

    1958-04-01

    A device is described that is specifically designed to cast uraniumn fuel rods in a vacuunn, in order to obtain flawless, nonoxidized castings which subsequently require a maximum of machining or wastage of the expensive processed material. A chamber surrounded with heating elements is connected to the molds, and the entire apparatus is housed in an airtight container. A charge of uranium is placed in the chamber, heated, then is allowed to flow into the molds While being rotated. Water circulating through passages in the molds chills the casting to form a fine grained fuel rod in nearly finished form.

  6. Bainite obtaining in cast iron with carbides castings

    Directory of Open Access Journals (Sweden)

    S. Pietrowski

    2010-01-01

    Full Text Available In these paper the possibility of upper and lower bainite obtaining in cast iron with carbides castings are presented. Conditions, when in cast iron with carbides castings during continuous free air cooling austenite transformation to upper bainite or its mixture with lower bainte proceeds, have been given. A mechanism of this transformation has been given, Si, Ni, Mn and Mo distribution in the eutectic cell has been tested and hardness of tested castings has been determined.

  7. Colour Metallography of Cast Iron

    Institute of Scientific and Technical Information of China (English)

    Zhou Jiyang; Liu Jincheng

    2011-01-01

    White Cast Iron (Ⅰ) White cast iron or ‘white iron' refers to the type of cast iron in which all of the carbon exists as carbide;there is no graphite in the as-cast structure and the fractured surface shows a white colour.White cast iron can be divided in three classes:· Normal white cast iron — this iron contains only C,Si,Mn,P and S,with no other alloying elements.· Low-alloy white cast iron — the total mass fraction of alloying elements is less than 5%.

  8. Casting Characteristics of Aluminum Die Casting Alloys

    Energy Technology Data Exchange (ETDEWEB)

    Makhlouf M. Makhlouf; Diran Apelian

    2002-02-05

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

  9. Colour Metallography of Cast Iron

    Institute of Scientific and Technical Information of China (English)

    Zhou Jiyang; Ph.D Liu Jincheng

    2010-01-01

    @@ Note: This book consists of five sections: Chapter 1 Introduction, Chapter 2 Grey Iron, Chapter 3 Spheroidal Graphite Cast Iron, Chapter 4 Vermicular Cast Iron, and Chapter 5 White Cast Iron. CHINA FOUNDRY publishes this book in several parts serially, starting from the first issue of 2009.

  10. Evaluation of an improved centrifugal casting machine.

    Science.gov (United States)

    Donovan, T E; White, L E

    1985-05-01

    A Type III gold alloy, a silver-palladium alloy, and a base metal alloy were cast in two different centrifugal casting machines. With the number of complete cast mesh squares as an indicator of castability, the Airspin casting machine produced superior castings with all three alloys. The base metal alloy produced the greatest number of complete squares with both casting machines.

  11. The casting of western sculpture during the XIXth century: sand casting versus lost wax casting

    NARCIS (Netherlands)

    Beentjes, T.P.C.

    2014-01-01

    This paper will discuss research into bronze casting techniques as practiced during the XIXth and early XXth century. Both natural sand casting (fonte au sable naturel) and lost wax casting (fonte à la cire perdue) were employed during this period and sometimes rivalled for commissions. Before the X

  12. Colour Metallography of Cast Iron

    Institute of Scientific and Technical Information of China (English)

    Zhou Jiyang; Liu Jincheng

    2010-01-01

    @@ Chapter 3 Spheroidal Graphite Cast Iron(I) Spheroidal Graphite Cast Iron, SG iron in short, refers to the cast iron in which graphite precipitates as spheroidal shape during solidification of liquid iron. The graphite in common commercial cast iron can only be changed from flake to spheroidal shape by spheroidising treatment. Since spheroidal graphite reduces the cutting effect of stress concentration, the metal matrix strength of SG iron can be applied around 70%-90%, thus the mechanical property of SG iron is significantly superior to other cast irons;even the tensile strength of SG iron is higher than that carbon steel.

  13. Cast iron - a predictable material

    Directory of Open Access Journals (Sweden)

    Jorg C. Sturm

    2011-02-01

    Full Text Available High strength compacted graphite iron (CGI or alloyed cast iron components are substituting previously used non-ferrous castings in automotive power train applications. The mechanical engineering industry has recognized the value in substituting forged or welded structures with stiff and light-weight cast iron castings. New products such as wind turbines have opened new markets for an entire suite of highly reliable ductile iron cast components. During the last 20 years, casting process simulation has developed from predicting hot spots and solidification to an integral assessment tool for foundries for the entire manufacturing route of castings. The support of the feeding related layout of the casting is still one of the most important duties for casting process simulation. Depending on the alloy poured, different feeding behaviors and self-feeding capabilities need to be considered to provide a defect free casting. Therefore, it is not enough to base the prediction of shrinkage defects solely on hot spots derived from temperature fields. To be able to quantitatively predict these defects, solidification simulation had to be combined with density and mass transport calculations, in order to evaluate the impact of the solidification morphology on the feeding behavior as well as to consider alloy dependent feeding ranges. For cast iron foundries, the use of casting process simulation has become an important instrument to predict the robustness and reliability of their processes, especially since the influence of alloying elements, melting practice and metallurgy need to be considered to quantify the special shrinkage and solidification behavior of cast iron. This allows the prediction of local structures, phases and ultimately the local mechanical properties of cast irons, to asses casting quality in the foundry but also to make use of this quantitative information during design of the casting. Casting quality issues related to thermally driven

  14. Melting and casting of FeAl-based cast alloy

    Energy Technology Data Exchange (ETDEWEB)

    Sikka, V.K. [Oak Ridge National Lab., TN (United States); Wilkening, D. [Columbia Falls Aluminum Co., Columbia Falls, MT (United States); Liebetrau, J.; Mackey, B. [AFFCO, L.L.C., Anaconda, MT (United States)

    1998-11-01

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

  15. Melting and casting of FeAl-based cast alloy

    Energy Technology Data Exchange (ETDEWEB)

    Sikka, V.K. [Oak Ridge National Lab., TN (United States). Metals and Ceramics Div.; Wilkening, D. [Columbia Falls Aluminum Co., 2000 Aluminum Dr., Columbia Falls, MT 59912 (United States); Liebetrau, J.; Mackey, B. [AFFCO, L.L.C., P.O. Box 1071, Anaconda, MT 59711 (United States)

    1998-12-31

    The FeAl-based intermetallic alloys are of great interest because of their low density, low raw material cost, and excellent resistance to high-temperature oxidation, sulfidation, carburization, and molten salts. The applications based on these unique properties of FeAl require methods to melt and cast these alloys into complex-shaped castings and centrifugal cast tubes. This paper addresses the melting-related issues and the effect of chemistry on the microstructure and hardness of castings. It is concluded that the use of the Exo-Melt{sup TM} process for melting and the proper selection of the aluminum melt stock can result in porosity-free castings. The FeAl alloys can be melted and cast from the virgin and revert stock. A large variation in carbon content of the alloys is possible before the precipitation of graphite flakes occurs. Titanium is a very potent addition to refine the grain size of castings. A range of complex sand castings and two different sizes of centrifugal cast tubes of the alloy have already been cast. (orig.) 18 refs.

  16. [Casting faults and structural studies on bonded alloys comparing centrifugal castings and vacuum pressure castings].

    Science.gov (United States)

    Fuchs, P; Küfmann, W

    1978-07-01

    The casting processes in use today such as centrifugal casting and vacuum pressure casting were compared with one another. An effort was made to answer the question whether the occurrence of shrink cavities and the mean diameter of the grain of the alloy is dependent on the method of casting. 80 crowns were made by both processes from the baked alloys Degudent Universal, Degudent N and the trial alloy 4437 of the firm Degusa. Slice sections were examined for macro and micro-porosity and the structural appearance was evaluated by linear analysis. Statistical analysis showed that casting faults and casting structure is independent of the method used and their causes must be found in the conditions of casting and the composition of the alloy.

  17. Light metal compound casting

    Institute of Scientific and Technical Information of China (English)

    Konrad J.M.PAPIS; Joerg F.LOEFFLER; Peter J.UGGOWITZER

    2009-01-01

    'Compound casting'simplifies joining processes by directly casting a metallic melt onto a solid metal substrate. A continuously metallurgic transition is very important for industrial applications, such as joint structures of spaceframe constructions in transport industry. In this project, 'compound casting' of light metals is investigated, aiming at weight-saving. The substrate used is a wrought aluminium alloy of type AA5xxx, containing magnesium as main alloying element. The melts are aluminium alloys, containing various alloying elements (Cu, Si, Zn), and magnesium. By replacing the natural oxygen layer with a zinc layer, the inherent wetting difficulties were avoided, and compounds with flawless interfaces were successfully produced (no contraction defects, cracks or oxides). Electron microscopy and EDX investigations as well as optical micrographs of the interfacial areas revealed their continu-ously metallic constitution. Diffusion of alloying elements leads to heat-treatable microstructures in the vicinity of the joining interfaces in Al-Al couples. This permits significant variability of mechanical properties. Without significantly cutting down on wettability, the formation of low-melting intermetallic phases (Al3Mg2 and AI12Mg17 IMPs) at the interface of Al-Mg couples was avoided by applying a protec-tive coating to the substrate.

  18. Bimetallic layered castings alloy steel – carbon cast steel

    Directory of Open Access Journals (Sweden)

    T. Wróbel

    2011-01-01

    Full Text Available In paper is presented technology of bimetallic layered castings based on founding method of layer coating directly in cast processso-called method of mould cavity preparation. Prepared castings consist two fundamental parts i.e. bearing part and working part (layer. The bearing part of bimetallic layered casting is typical foundry material i.e. ferritic-pearlitic carbon cast steel, whereas working part (layer is plate of austenitic alloy steel sort X10CrNi 18-8. The ratio of thickness between bearing and working part is 8:1. The quality of the bimetallic layered castings was evaluated on the basis of ultrasonic NDT (non-destructive testing, structure and macro- and microhardness researches.

  19. Casting larger polycrystalline silicon ingots

    Energy Technology Data Exchange (ETDEWEB)

    Wohlgemuth, J.; Tomlinson, T.; Cliber, J.; Shea, S.; Narayanan, M.

    1995-08-01

    Solarex has developed and patented a directional solidification casting process specifically designed for photovoltaics. In this process, silicon feedstock is melted in a ceramic crucible and solidified into a large grained semicrystalline silicon ingot. In-house manufacture of low cost, high purity ceramics is a key to the low cost fabrication of Solarex polycrystalline wafers. The casting process is performed in Solarex designed casting stations. The casting operation is computer controlled. There are no moving parts (except for the loading and unloading) so the growth process proceeds with virtually no operator intervention Today Solarex casting stations are used to produce ingots from which 4 bricks, each 11.4 cm by 11.4 cm in cross section, are cut. The stations themselves are physically capable of holding larger ingots, that would yield either: 4 bricks, 15 cm by 15 an; or 9 bricks, 11.4 cm by 11.4 an in cross-section. One of the tasks in the Solarex Cast Polycrystalline Silicon PVMaT Program is to design and modify one of the castings stations to cast these larger ingots. If successful, this effort will increase the production capacity of Solarex`s casting stations by 73% and reduce the labor content for casting by an equivalent percentage.

  20. Fracture Mechanisms in Steel Castings

    Directory of Open Access Journals (Sweden)

    Z. Stradomski

    2013-07-01

    Full Text Available The investigations were inspired with the problem of cracking of steel castings during the production process. A single mechanism of decohesion - the intergranular one - occurs in the case of hot cracking, while a variety of structural factors is decisive for hot cracking initiation, depending on chemical composition of the cast steel. The low-carbon and low-alloyed steel castings crack due to the presence of the type II sulphides, the cause of cracking of the high-carbon tool cast steels is the net of secondary cementite and/or ledeburite precipitated along the boundaries of solidified grains. Also the brittle phosphor and carbide eutectics precipitated in the final stage solidification are responsible for cracking of castings made of Hadfield steel. The examination of mechanical properties at 1050°C revealed low or very low strength of high-carbon cast steels.

  1. Development of Refractories for Continuous Casting

    Institute of Scientific and Technical Information of China (English)

    TIAN Shouxin; JIN Congjin; YAO Jinfu; LI Zeya

    2004-01-01

    The paper introduces refractories for continuous casting, especially, refractories for continuous casting for clean steel in baosteel. Developing direction of refractories for continuous casting has been pointed out to satisfy the new metallurgical operating practice.

  2. Segregation in cast products

    Indian Academy of Sciences (India)

    A Ghosh

    2001-02-01

    Microsegregation gets eliminated significantly if subsequent hot working and/or annealing are done on cast products. Macrosegregation however persists, causing problems in quality, and hence, has to be attended to. Microsegregation is a consequence of rejection of solutes by the solid into the interdendritic liquid. Scheil’s equation is mostly employed. However, other equations have been proposed, which take into account diffusion in solid phase and/or incomplete mixing in liquid. Macrosegregation results from movements of microsegregated regions over macroscopic distances due to motion of liquid and free crystals. Motion of impure interdendritic liquid causes regions of positive macrosegregation, whereas purer solid crystals yield negative macrosegregation. Flow of interdendritic liquid is primarily natural convection due to thermal and solutal buoyancy, and partly forced convection due to suction by shrinkage cavity formation etc. The present paper briefly deals with fundamentals of the above and contains some recent studies as well. Experimental investigations in molten alloys do not allow visualization of the complex flow pattern as well as other phenomena, such as dendrite-tip detachment. Experiments with room temperature analogues, and mathematical modelling have supplemented these efforts. However, the complexity of the phenomena demands simplifying assumptions. The agreement with experimental data is mostly qualitative. The paper also briefly discusses centreline macrosegregation during continuous casting of steel, methods to avoid it, and the, importance of early columnar-to-equiaxed transition (CET) as well as the fundamentals of CET.

  3. Biomaterials by freeze casting.

    Science.gov (United States)

    Wegst, Ulrike G K; Schecter, Matthew; Donius, Amalie E; Hunger, Philipp M

    2010-04-28

    The functional requirements for synthetic tissue substitutes appear deceptively simple: they should provide a porous matrix with interconnecting porosity and surface properties that promote rapid tissue ingrowth; at the same time, they should possess sufficient stiffness, strength and toughness to prevent crushing under physiological loads until full integration and healing are reached. Despite extensive efforts and first encouraging results, current biomaterials for tissue regeneration tend to suffer common limitations: insufficient tissue-material interaction and an inherent lack of strength and toughness associated with porosity. The challenge persists to synthesize materials that mimic both structure and mechanical performance of the natural tissue and permit strong tissue-implant interfaces to be formed. In the case of bone substitute materials, for example, the goal is to engineer high-performance composites with effective properties that, similar to natural mineralized tissue, exceed by orders of magnitude the properties of its constituents. It is still difficult with current technology to emulate in synthetic biomaterials multi-level hierarchical composite structures that are thought to be the origin of the observed mechanical property amplification in biological materials. Freeze casting permits to manufacture such complex, hybrid materials through excellent control of structural and mechanical properties. As a processing technique for the manufacture of biomaterials, freeze casting therefore has great promise.

  4. Education and Caste in India

    Science.gov (United States)

    Chauhan, Chandra Pal Singh

    2008-01-01

    This paper analyses the policy of reservation for lower castes in India. This policy is similar to that of affirmative action in the United States. The paper provides a brief overview of the caste system and discusses the types of groups that are eligible for reservation, based on data from government reports. The stance of this paper is that…

  5. Theory of batchwise centrifugal casting

    NARCIS (Netherlands)

    Biesheuvel, P. Maarten; Nijmeijer, Arian; Verweij, Henk

    1998-01-01

    In batchwise centrifugal casting a cylindrical mold is filled with suspension and rotated rapidly around its axis. This results in the movement of the particulate phase toward the cylinder wall and the formation of a tubular cast. Theory is presented for particle transport in the suspension phase an

  6. Lost Foam Casting in China

    Institute of Scientific and Technical Information of China (English)

    YE Sheng-ping; WU Zhi-chao

    2006-01-01

    @@ 1. Lost Foam Casting Committee of Foundry Institution of Chinese Mechanical Engineering Society (FICMES) From the beginning of the 1990s, China entered a research and expansion climax in lost foam casting technology realm after the United States, Germany, and Japan etc.

  7. Colour Metallography of Cast Iron

    Institute of Scientific and Technical Information of China (English)

    Zhou Jiyang; Liu Jincheng

    2009-01-01

    @@ This book consists of five sections:Chapter 1 Introduction,Chapter 2 Grey Iron,Chapter 3 Ductile Iron,Chapter 4Vermicular Cast Iron,and Chapter 5 White Cast Iron. CHINA FOUNDRY publishs this book in several parts serially,starting from the first issue of 2009.

  8. EVOLUTION OF AS—CAST MICROSTRUCTURES OF 356 ALUMINIUM ALLOY CAST BY LIQUIDUS CASTING

    Institute of Scientific and Technical Information of China (English)

    J.Dong; G.M.Lu; 等

    2003-01-01

    A new method (liquidus casting)was used for 356 Al alloy semi-solid slurry mak-ing.The structures of 356 Al alloy cast by a fe mould and semi-continuous casting machine at different temperatures were inves tigated.How the globular grains form was qlso discussed.The results show that either being cast by single Fe mould or semi-continuous machine,the microstructures are not conventional dendrites but fine and net-globular grains.The average grain size is smaller than 30μm and suitable enough for thixoforming,meanwhile it can improve the mechanical properties of fol-lowing products.Under the suitable casting velocity and cooling intensity,most of global grains prolong their global browth and collide with each other before dendritic growth because of the large amount of the nucleation sites.

  9. Comparison of marginal accuracy of castings fabricated by conventional casting technique and accelerated casting technique: An in vitro study

    Directory of Open Access Journals (Sweden)

    S Srikanth Reddy

    2013-01-01

    Full Text Available Background: Conventional casting technique is time consuming when compared to accelerated casting technique. In this study, marginal accuracy of castings fabricated using accelerated and conventional casting technique was compared. Materials and Methods: 20 wax patterns were fabricated and the marginal discrepancy between the die and patterns were measured using Optical stereomicroscope. Ten wax patterns were used for Conventional casting and the rest for Accelerated casting. A Nickel-Chromium alloy was used for the casting. The castings were measured for marginal discrepancies and compared. Results: Castings fabricated using Conventional casting technique showed less vertical marginal discrepancy than the castings fabricated by Accelerated casting technique. The values were statistically highly significant. Conclusion: Conventional casting technique produced better marginal accuracy when compared to Accelerated casting. The vertical marginal discrepancy produced by the Accelerated casting technique was well within the maximum clinical tolerance limits. Clinical Implication: Accelerated casting technique can be used to save lab time to fabricate clinical crowns with acceptable vertical marginal discrepancy.

  10. NUMERICAL MODELING OF HARDENING OF UNINTERRUPTEDLY-CASTED BRONZE CASTING

    Directory of Open Access Journals (Sweden)

    E. I. Marukovich

    2009-01-01

    Full Text Available The three-dimensional numerical model for calculation of thermal fields during solidification of continuously casted bronze casting is developed. Coefficients of heat transfer on borders of calculation areas on the basis of the solution of inverse heat transfer conduction problem are determined. The analysis of thermal fields, depending on loop variables of drawing and the sizes of not cooled zone of crystallizer is curried out.

  11. Modelling of flow phenomena during DC casting

    NARCIS (Netherlands)

    Zuidema, J.

    2005-01-01

    Modelling of Flow Phenomena during DC Casting Jan Zuidema The production of aluminium ingots, by semi-continuous casting, is a complex process. DC Casting stands for direct chill casting. During this process liquid aluminium transforms to solid aluminium while cooling down. This is not an instanta

  12. Casting Using A Polystyrene Pattern

    Science.gov (United States)

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

    1993-01-01

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

  13. The CAST Time Projection Chamber

    CERN Document Server

    Autiero, D; Cébrian, S; Carmona, J M; Chesi, Enrico Guido; Davenport, M; Delattre, M; Di Lella, L; Formenti, F; Gomez, H; Hasinoff, M; Irastorza, I G; Lakic, B; Luzón, G; Morales, J; Musa, L; Ortiz, A; Placci, A; Rodríguez, A; Ruz, J; Villar, J A; Zioutas, K

    2007-01-01

    One of the three X-ray detectors of the CAST experiment searching for solar axions is a Time Projection Chamber (TPC) with a multi-wire proportional counter (MWPC) as a readout structure. Its design has been optimized to provide high sensitivity to the detection of the low intensity X-ray signal expected in the CAST experiment. A low hardware threshold of 0.8 keV is safely set during normal data taking periods, and the overall efficiency for the detection of photons coming from conversion of solar axions is 62 %. Shielding has been installed around the detector, lowering the background level to 4.10 x 10^-5 counts/cm^2/s/keV between 1 and 10 keV. During phase I of the CAST experiment the TPC has provided robust and stable operation, thus contributing with a competitive result to the overall CAST limit on axion-photon coupling and mass.

  14. Some Theoretical Considerations on Caste

    Directory of Open Access Journals (Sweden)

    Madhusudan Subedi

    2014-05-01

    Full Text Available Caste as a system of social stratification was an encompassing system in the past. There was reciprocal system of exchange goods and services. With time, occupation and mode of generation of livelihood of various caste groups changed, and the traditional form of jajmani system fizzled out. This paper provides an account of changing perspectives of caste relations in social science writing and political discourse. The discourse of caste has been shifted from ritual hierarchy and social discrimination to an instrument to mobilize people for economic and political gain. DOI: http://dx.doi.org/10.3126/dsaj.v7i0.10437 Dhaulagiri Journal of Sociology and Anthropology Vol. 7, 2013; 51-86

  15. Inoculation of chromium white cast iron

    Directory of Open Access Journals (Sweden)

    D. Kopyciński

    2009-01-01

    Full Text Available It has been proved that an addition of boron carbide introduced as an inoculant to the chromium white cast iron changes the structureof castings. Castings after inoculation revealed a different structure with numerous grains. Primary precipitates of chromium carbide also appeared, reducing the mechanical properties of as-cast parts. Properly established heat treatment regime makes chromium iron castings regain their, originally high, mechanical properties.

  16. Colour Metallography of Cast Iron

    Institute of Scientific and Technical Information of China (English)

    Zhou Jiyang; Liu Jincheng

    2011-01-01

    @@ Vermicular graphite cast iron(VG iron for short in the following sections)is a type of cast iron in which the graphite is intermediate in shape between flake and spheroidal.Compared with the normal flake graphite in grey iron, the graphite in VG iron is shorter and thicker and shows a curved, more rounded shape.Because its outer contour is exactly like a worm, hence it is called vermicular graphite.

  17. Agile Manufacturing Development of Castings

    Science.gov (United States)

    2007-11-02

    responsible for con- verting the available 2D CATIA casting design into a 3D Pro/Engineering geometric model of the casting, for use by Clinkenbeard...changes to the draw- ings. MWM. As the part designer, MWM reviewed and evalu- ated proposed changes to the design. MWM also updated the CATIA ...creation of solid models of the cores and molds, using IGES translations of the CATIA files secured from MWM through GE Transportation Sys- tems. Due

  18. Moldless casting by laser

    Science.gov (United States)

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

    1997-09-01

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

  19. Light metal compound casting

    Institute of Scientific and Technical Information of China (English)

    Konrad; J.; M.; PAPIS; Joerg; F.; LOEFFLER; Peter; J.; UGGOWITZER

    2009-01-01

    ‘Compound casting’simplifies joining processes by directly casting a metallic melt onto a solid metal substrate. A continuously metallurgic transition is very important for industrial applications, such as joint structures of spaceframe constructions in transport industry. In this project, ‘compound casting’ of light metals is investigated, aiming at weight-saving. The substrate used is a wrought aluminium alloy of type AA5xxx, containing magnesium as main alloying element. The melts are aluminium alloys, containing various alloying elements (Cu, Si, Zn), and magnesium. By replacing the natural oxygen layer with a zinc layer, the inherent wetting difficulties were avoided, and compounds with flawless interfaces were successfully produced (no contraction defects, cracks or oxides). Electron microscopy and EDX investigations as well as optical micrographs of the interfacial areas revealed their continu- ously metallic constitution. Diffusion of alloying elements leads to heat-treatable microstructures in the vicinity of the joining interfaces in Al-Al couples. This permits significant variability of mechanical properties. Without significantly cutting down on wettability, the formation of low-melting intermetallic phases (Al3Mg2 and Al12Mg17 IMPs) at the interface of Al-Mg couples was avoided by applying a protective coating to the substrate.

  20. EVOLUTION OF AS-CAST MICROSTRUCTURES OF 356 ALUMINIUM ALLOY CAST BY LIQUIDUS CASTING

    Institute of Scientific and Technical Information of China (English)

    J. Dong; G.M. Lu; J.Z. Cui; Z.H. Zhao

    2003-01-01

    A new method (liquidus casting) was used for 356 Al alloy semi-solid slurry mak-ing. The structures of 356 Al alloy cast by a Fe mould and semi-continuous castingmachine at different temperatures were investigated. How the globular grains formwas also discussed. The results show that either being cast by single Fe mould orsemi-continuous machine, the microstructures are not conventional dendrites but fineand net-globular grains. The average grain size is smaller than 30μm and suitableenough for thixoforming, meanwhile it can improve the mechanical properties of fol-lowing products. Under the suitable casting velocity and cooling intensity, most ofglobal grains prolong their global growth and collide with each other before dendriticgrowth because of the large amount of the nucleation sites.

  1. Untouchable castes of Uttar Pradesh

    Directory of Open Access Journals (Sweden)

    Kharinin Artem Igorevich

    2015-04-01

    Full Text Available The Untouchable Castes of Uttar Pradesh are examined in this article. This region is one of the most populated in India. Also it is one of the most social mixed-composed in whole State. That’s why main conclusions which were made on this material can be extrapolated to all social space of country. The authors choose four ethno-caste groups, which represent the majority in untouchables and the three smallest in jaties. Their positions in regional hierarchy and economic specialization are analyzed in detail. There are a lot of information about their number, social structure, literacy rating, endogamy, day-to-day practices, customs and other features. Special accents were pointed on mind orientation of their elites toward integration in modern society or, conversely, toward the conservation of traditional forms of existence. The issues of origin and social evolution of untouchable castes of Uttar Pradesh are examined. There is assessment of castes’ sanskritization or other forms of social selfdevelopment. The quality of “scheduled” castes social environment is analyzed. As a marks of its positiveness the data about discrimination untouchables from other social groups and degree of political representativeness of “scheduled” castes, accessibility of education and labour were chosen. The conclusions were made about development degree of some castes. The factors that play role in positive changes in contemporary conditions were determined. The authors put forward their own hypothesis of future development of untouchable castes in Uttar Pradesh. Empiric base of this article was established on sources that have Indian origin and historical and social research of outstanding western indologies.

  2. Development of vacuum die-casting process

    Institute of Scientific and Technical Information of China (English)

    Masashi Uchida

    2009-01-01

    The vacuum die-casting process, started 25 years ago in Japan, has been widely applied. This technology contributes very much to improvement of castings quality. The main factor causing the defects of die castings is the trapped air in the mold cavity, while the key technology of vacuum die-casting process is to avoid the trapped air effectively by evacuating the cavity before casting. At the same time, due to the shot speed and the casting pressure reduced in half, the service life of the die is prolonged and the productivity is enhanced, as well. Vacuum die-casting process is of great significance in improving the die castings quality and making up the shortcomings of super-high-speed shot casting.

  3. As-Cast Acicular Ductile Aluminum Cast Iron

    Institute of Scientific and Technical Information of China (English)

    S M Mostafavi Kashani; S M A Boutorabi

    2009-01-01

    The effects of nickel (2.2%)and molybdenum (0.6%)additions on the kinetics, microstructure, and me-chanical properties of ductile aluminum cast iron were studied under the as-cast and tempered conditions. Test bars machined from cast to size samples were used for mechanical and metallurgical studies. The results showed that adding nickel and molybdenum to the base iron produced an upper bainitic structure, resulting in an increase in strength and hardness. The same trend was shown when the test bars were tempered at 300 ℃ in the range of 300℃ to 400 ℃. The elongation increased with increasing the temperature from 300 ℃ to 400 ℃. The carbon content of the retained austenite also increased with increasing the temperature. The results also showed that the kinetics, mi-crostructure, and mechanical properties of this iron were similar to those of Ni-Mo alloyed silicon ductile iron.

  4. Research progress on squeeze casting in China

    Institute of Scientific and Technical Information of China (English)

    Li Yuanyuan; Zhang Weiwen; Zhao Haidong; You Dongdong; Zhang Datong; Shao Ming; Zhang Wen

    2014-01-01

    Squeeze casting is a technology with short route, high efficiency and precise forming, possessing features of casting and plastic processing. It is widely used to produce high performance metallic structural parts. As energy conservation and environmental protection concerns have risen, lightweight and high performance metal parts are urgently needed, which accelerated the development of squeeze casting technology over the past two decades in China. In this paper, research progress on squeeze casting aloys, typical parts manufacturing and development of squeeze casting equipment in China are introduced. The future trend and development priorities of squeeze casting are discussed.

  5. Energy Consumption of Die Casting Operations

    Energy Technology Data Exchange (ETDEWEB)

    Jerald Brevick; clark Mount-Campbell; Carroll Mobley

    2004-03-15

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

  6. CAST Physics Proposal to SPSC

    CERN Document Server

    CAST, Collaboration

    2011-01-01

    The CAST experiment has the potential to search for solar axions (dark matter particle candidates) or other particles with similar coupling. E.g., paraphtons (Hidden Sector), chameleons (dark energy), while considering the possibility whether CAST could be transformed to an antenna for relic axions with rest mass up to 0.1 to 1meV. While axion searches suggest detectors with lower background, paraphoton and chameleon searches require detectors with sub-keV threshold energy and the use of transparent windows in front of the Micromegas detectors, which cover 3 out of the 4 CAST magnet exits. Ongoing theoretical estimates and experimental investigations will define the priorities of the suggested 4 physics items of this proposal for the period 2012-2014.

  7. WEAR-RESISTANCE OF CHROMIC CAST IRONS OF EUTECTIC COMPOSITION

    Directory of Open Access Journals (Sweden)

    K. E. Baranovskij

    2009-01-01

    Full Text Available Casting of wear-resistant chrome cast irons in combined molds and iron chills is studied. Application of these ways of casting results in blending of carbides and increasing of hardness of castings.

  8. Casting behavior of titanium alloys in a centrifugal casting machine.

    Science.gov (United States)

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

    2003-05-01

    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.

  9. CAST-IRONS AT HIGH TEMPERATURES

    Directory of Open Access Journals (Sweden)

    A. N. Krutilin

    2008-01-01

    Full Text Available The results of investigations of physical-mechanical characteristics of cast iron slugs, received by semicontinuos way of casting, at temperatures from 850 up to 1100^ С are given. 

  10. CONTINUOUSLY-CYCLIC CASTING OF HOLLOW CYLINDER SLUGS OF HIGH-CHROMIUM CAST IRON

    Directory of Open Access Journals (Sweden)

    E. I. Marukovich

    2009-01-01

    Full Text Available The analysis of castings formation is presented and the package of measures dircted on increase of stability of casting process is developed. Parametres of casting of hollow cylindrical billets by the method of directional solidification out of white high-chromium cast iron are defined.

  11. Developing technological process of obtaining giality casts

    Directory of Open Access Journals (Sweden)

    A. Issagulov

    2014-10-01

    Full Text Available The article considers the process of manufacturing castings using sand-resin forms and alloying furnace. Were the optimal technological parameters of manufacturing shell molds for the manufacture of castings of heating equipment. Using the same upon receipt of castings by casting in shell molds furnace alloying and deoxidation of the metal will provide consumers with quality products and have a positive impact on the economy in general engineering.

  12. When Your Child Needs a Cast

    Science.gov (United States)

    ... 1- to 2-Year-Old When Your Child Needs a Cast KidsHealth > For Parents > When Your Child Needs a Cast Print A A A What's in ... A cast wraps around the broken area and needs to be removed by a doctor when the ...

  13. Prediction of Microporosity in Shrouded Impeller Castings

    Energy Technology Data Exchange (ETDEWEB)

    Viswanathan, S. Nelson, C.D.

    1998-09-01

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

  14. Pressure distribution in centrifugal dental casting.

    Science.gov (United States)

    Nielsen, J P

    1978-02-01

    Equations are developed for liquid metal pressure in centrifugal dental casting, given the instantaneous rotational velocity, density, and certain dimensions of the casting machine and casting pattern. A "reference parabola" is introduced making the fluid pressure concept more understandable. A specially designed specimen demonstrates experimentally the reference parabola at freezing.

  15. Squeeze Casting of Steel Weapon Components

    Science.gov (United States)

    1976-09-01

    equipment. The squeeze casting process also differs from rheo- casting.(10-12) Unlike the former, the rheocasting process (8) "Ferrous Die Casting...various phases of rheocasting . At least so far, the process has not been applied to fabrication of complex steel components of the type that are under

  16. Colour Metallography of Cast Iron

    Institute of Scientific and Technical Information of China (English)

    Zhou Jiyang; Liu Jincheng

    2010-01-01

    @@ Spheroidal Graphite Cast Iron(Ⅳ) 3.7 Segregation of SG iron The non-uniform distribution of solute elements during solidification results in the micro segregation of SG iron.As for the redistribution of elements in the phases of the solidification structure,there is no intrinsic difference between SG iron and grey iron[132].

  17. Search for chameleons with CAST

    DEFF Research Database (Denmark)

    Anastassopoulos, V.; Arik, M.; Aune, S.

    2015-01-01

    energy threshold used for axions from 1 keV to 400 eV CAST became sensitive to the converted solar chameleon spectrum which peaks around 600 eV. Even though we have not observed any excess above background, we can provide a 95% C.L. limit for the coupling strength of chameleons to photons of βΥ≤1011...

  18. Inoculation Effects of Cast Iron

    Directory of Open Access Journals (Sweden)

    E. Fraś

    2012-12-01

    Full Text Available The paper presents a solidification sequence of graphite eutectic cells of A and D types, as well as globular and cementite eutectics. The morphology of eutectic cells in cast iron, the equations for their growth and the distances between the graphite precipitations in A and D eutectic types were analyzed. It is observed a critical eutectic growth rate at which one type of eutectic transformed into another. A mathematical formula was derived that combined the maximum degree of undercooling, the cooling rate of cast iron, eutectic cell count and the eutectic growth rate. One type of eutectic structure turned smoothly into the other at a particular transition rate, transformation temperature and transformational eutectic cell count. Inoculation of cast iron increased the number of eutectic cells with flake graphite and the graphite nodule count in ductile iron, while reducing the undercooling. An increase in intensity of inoculation caused a smooth transition from a cementite eutectic structure to a mixture of cementite and D type eutectic structure, then to a mixture of D and A types of eutectics up to the presence of only the A type of eutectic structure. Moreover, the mechanism of inoculation of cast iron was studied.

  19. Colour Metallography of Cast Iron

    Institute of Scientific and Technical Information of China (English)

    Zhou Jiyang; Liu Jincheng

    2010-01-01

    @@ Spheroidal Graphite Cast Iron(Ⅲ) 3.6 Solidification morphology of SG iron Solidification morphology refers to the description of change,distribution and interrelationship of the solidification structures such as graphite spheroids,austenite,eutectic cells,etc.[99

  20. Tape casting of magnesium oxide.

    Energy Technology Data Exchange (ETDEWEB)

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

    2008-02-01

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

  1. CENTRIFUGAL CASTING OF ANTIFRICTION SILUMIN

    Directory of Open Access Journals (Sweden)

    V. Ju. Stetsenko

    2010-01-01

    Full Text Available It is shown that the way of centrifugal casting into water-cooled mould with vertical rotation axis enables to receive hollow slugs with diameter 100–250 mm, with height under 200 mm with wall thickness under 15 mm of antifriction silumin АК15М3, which will replace expensive antifriction bronze.

  2. Cern Axion Solar Telescope (CAST)

    CERN Multimedia

    2002-01-01

    The CERN Solar Axion Telescope, CAST, aims to shed light on a 30-year-old riddle of particle physics by detecting axions originating from the 15 million degree plasma in the Sun 's core. Axions were proposed as an extension to the Standard Model of particle physics to explain why CP violation is observed in weak but not strong interactions.

  3. The CAST time projection chamber

    Science.gov (United States)

    Autiero, D.; Beltrán, B.; Carmona, J. M.; Cebrián, S.; Chesi, E.; Davenport, M.; Delattre, M.; Di Lella, L.; Formenti, F.; Irastorza, I. G.; Gómez, H.; Hasinoff, M.; Lakic, B.; Luzón, G.; Morales, J.; Musa, L.; Ortiz, A.; Placci, A.; Rodrigurez, A.; Ruz, J.; Villar, J. A.; Zioutas, K.

    2007-06-01

    One of the three x-ray detectors of the CERN Axion Solar Telescope (CAST) experiment searching for solar axions is a time projection chamber (TPC) with a multi-wire proportional counter (MWPC) as a readout structure. Its design has been optimized to provide high sensitivity to the detection of the low intensity x-ray signal expected in the CAST experiment. A low hardware threshold of 0.8 keV is set to a safe level during normal data taking periods, and the overall efficiency for the detection of photons coming from conversion of solar axions is 62%. Shielding has been installed around the detector, lowering the background level to 4.10 × 10-5 counts cm-2 s-1 keV-1 between 1 and 10 keV. During phase I of the CAST experiment the TPC has provided robust and stable operation, thus contributing with a competitive result to the overall CAST limit on axion photon coupling and mass.

  4. Advanced Lost Foam Casting Technology

    Energy Technology Data Exchange (ETDEWEB)

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

    2000-11-30

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

  5. Graphite Formation in Cast Iron

    Science.gov (United States)

    Stefanescu, D. M.

    1985-01-01

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

  6. Technological parameters of die casting and quality of casting from EN AC46500 alloy

    OpenAIRE

    2016-01-01

    Die casting represents the highest technological level of metal mold casting. This technology enables production of almost all final products without necessity of further processing. The important aspect of efficiency and production is a proper casting parameters setting. In the submitted paper following die casting parameters are analyzed: plunger pressing speed and pressure. The studied parameters most significantly affect a qualitative of castings from EN AC46500 alloy and they influence t...

  7. Continuous squeeze casting process by mass production

    Institute of Scientific and Technical Information of China (English)

    Yun Xia; Rich Jacques

    2006-01-01

    Squeeze casting has become the most competitive casting process in the automotive industry because of its many advantages over high pressure die casting (HPDC). Many squeeze casting R & D and small amount volume making have been implemented around the world, but the mass production control still exists problem. SPX Contech squeeze casting process P2000 successfully achieved the goal of mass production; it includes lower metal turbulence, less gas entrapment, minimum volumetric shrinkage, and thus less porosity. Like other casting processes, however, the quality of squeeze castings is still sensitive to process control and gate and runner design. Casting defects can form in both die-filling and metal solidification phases. The occurrence of casting defects is directly attributed to improper adjustment or lack of control of process parameters including metal filling velocity, temperature, dwell time, cooling pattern, casting design, and etc. This paper presents examples using P2000 techniques to improve part quality in the following areas: runner & gate design, casting & runner layout in the die, squeeze pin application, high thermal conductivityinserts, cooling/heating systems, spray & lubricant techniques,and part stress calculation from shrinkage or displacement prediction after stress relief.

  8. Prediction of Part Distortion in Die Casting

    Energy Technology Data Exchange (ETDEWEB)

    R. Allen Miller

    2005-03-30

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

  9. Process development of thin strip steel casting

    Energy Technology Data Exchange (ETDEWEB)

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

    1990-12-01

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

  10. Simulating a high pressure die casting

    Energy Technology Data Exchange (ETDEWEB)

    Goldak, J.; Zhou, J.; Downey, D.; Aldea, V.; Li, G.; Mocanita, M. [Carleton Univ., Ottawa, Ontario (Canada)

    2000-07-01

    High pressure die casting is simulated for parts with complex geometry such as a large automotive transmission case. The closed die is filled in approximately 40 ms, the casting cools in the closed die for approximately 40s, to open the die, eject the casting and spray the die cavity surface requires another 40s. This 3D cyclic process is simulated using the following coupled composite solvers: the energy equation in the die and in the casting with solidification; filling of the casting by a droplet or a Navier-Stokes solver, and thermal stress analysis of the casting machine, casting and die during the cycle. This thermal analysis can be done for both starting and stopping transients and for the cyclic steady state. The software enables this analysis to be done almost automatically by designers. (author)

  11. Inner surface roughness of complete cast crowns made by centrifugal casting machines.

    Science.gov (United States)

    Ogura, H; Raptis, C N; Asgar, K

    1981-05-01

    Six variables that could affect the surface roughness of a casting were investigated. The variables were (1) type of alloy, (2) mold temperature, (3) metal casting temperature, (4) casting machine, (5) sandblasting, and (6) location of each section. It was determined that the training portion of a complete cast crown had rougher surfaces than the leading portion. Higher mold and casting temperatures produced rougher castings, and this effect was more pronounced in the case of the base metal alloy. Sandblasting reduced the roughness, but produced scratched surfaces. Sandblasting had a more pronounced affect on the surface roughness of the base metal alloy cast either at a higher mold temperature or metal casting temperature. The morphology and the roughness profile of the original cast surface differed considerably with the type of alloy used.

  12. Pressure rig for repetitive casting

    Science.gov (United States)

    Vasquez, Peter (Inventor); Hutto, William R. (Inventor); Philips, Albert R. (Inventor)

    1989-01-01

    The invention is a pressure rig for repetitive casting of metal. 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 into the mold. A ceramic cavity which holds molten metal is lined with blanket-type insulating material, necessitating only a relining for subsequent use and eliminating the lengthy cavity preparation inherent in previous rigs. In addition, the expandable rubber diaphragm is protected by the insulating material thereby decreasing its vulnerability to heat damage. As a result of the improved design the life expectancy of the pressure rig contemplated by the present invention is more than doubled. Moreover, the improved heat protection has allowed the casting of brass and other alloys with higher melting temperatures than possible in the conventional pressure rigs.

  13. Search for chameleons with CAST

    Directory of Open Access Journals (Sweden)

    V. Anastassopoulos

    2015-10-01

    Full Text Available In this work we present a search for (solar chameleons with the CERN Axion Solar Telescope (CAST. This novel experimental technique, in the field of dark energy research, exploits both the chameleon coupling to matter (βm and to photons (βγ via the Primakoff effect. By reducing the X-ray detection energy threshold used for axions from 1 keV to 400 eV CAST became sensitive to the converted solar chameleon spectrum which peaks around 600 eV. Even though we have not observed any excess above background, we can provide a 95% C.L. limit for the coupling strength of chameleons to photons of βγ≲1011 for 1<βm<106.

  14. Search for chameleons with CAST

    CERN Document Server

    Anastassopoulos, V; Aune, S; Barth, K; Belov, A; Bräuninger, H; Cantatore, G; Carmona, J M; Cetin, S A; Christensen, F; Collar, J I; Dafni, T; Davenport, M; Desch, K; Dermenev, A; Eleftheriadis, C; Fanourakis, G; Ferrer-Ribas, E; Friedrich, P; Galán, J; García, J A; Gardikiotis, A; Garza, J G; Gazis, E N; Geralis, T; Giomataris, I; Hailey, C; Haug, F; Hasinoff, M D; Hofmann, D H H; Iguaz, F J; Irastorza, I G; Jacoby, J; Jakobsen, A; Jakovčić, K; Kaminski, J; Karuza, M; Kavuk, M; Krčmar, M; Krieger, C; Krüger, A; Lakić, B; Laurent, J M; Liolios, A; Ljubičić, A; Luzón, G; Neff, S; Ortega, I; Papaevangelou, T; Pivovarov, M J; Raffelt, G; Riege, H; Rosu, M; Ruz, J; Savvidis, I; Solanki, S K; Vafeiadis, T; Villar, J A; Vogel, J K; Yildiz, S C; Zioutas, K; Brax, P; Lavrentyev, I; Upadhye, A

    2015-01-01

    In this work we present a search for (solar) chameleons with the CERN Axion Solar Telescope (CAST). This novel experimental technique, in the field of dark energy research, exploits both the chameleon coupling to matter ($\\beta_{\\rm m}$) and to photons ($\\beta_{\\gamma}$) via the Primakoff effect. By reducing the X-ray detection energy threshold used for axions from 1$\\,$keV to 400$\\,$eV CAST became sensitive to the converted solar chameleon spectrum which peaks around 600$\\,$eV. Even though we have not observed any excess above background, we can provide a 95% C.L. limit for the coupling strength of chameleons to photons of $\\beta_{\\gamma}\\!\\lesssim\\!10^{11}$ for $1<\\beta_{\\rm m}<10^6$.

  15. Innovative algorithm for cast detection

    Science.gov (United States)

    Gasparini, Francesca; Schettini, Raimondo; Gallina, Paolo

    2001-12-01

    The paper describes a method for detecting a color cast (i.e. a superimposed dominant color) in a digital image without any a priori knowledge of its semantic content. The color gamut of the image is first mapped in the CIELab color space. The color distribution of the whole image and of the so-called Near Neutral Objects (NNO) is then investigated using statistical tools then, to determine the presence of a cast. The boundaries of the near neutral objects in the color space are set adaptively by the algorithm on the basis of a preliminary analysis of the image color gamut. The method we propose has been tuned and successfully tested on a large data set of images, downloaded from personal web-pages or acquired using various digital and traditional cameras.

  16. Rapid Cycle Casting of Steel

    Science.gov (United States)

    1981-07-01

    such as macrosegregation, hot tears, and blowholes are also difficult to control. Rheocasting l on the other hand, is a recent development which...viscosity. Advantages of the rheocasting process are: * Reduced attack of die or mold because of the reduced tempera- ture (by 1000 C for steel) and...4W W ’ V6W 4 1.2 THE SD PROCESS Many metals, including steel, can be cast at still lower tempera- soliifiction(2) tures than rheocasting by

  17. Computer precision simulation for titanium casting centrifugal mold filling of prescision titanium castings

    Directory of Open Access Journals (Sweden)

    Daming XU

    2004-08-01

    Full Text Available Computer simulation codes were developed based on proposed mathematical model for centrifugal mold filling processes and previous computer software for 3D mold filling and solidification of castings. Sample simulations were implemented for mold filling processes of precision titanium castings under gravity and different centrifugal casting techniques. The computation results show that the alloy melt has a much stronger mold filling ability for thin section castings unde a centrifugal force field than that only under the gravity. A "return back" mold filling manner is showed to be a reasonable technique for centrifugal casting processes, especially for thin section prcision castings.

  18. [The cast structure after vacuum-pressure casting and centrifugal casting].

    Science.gov (United States)

    Finger, W; Jung, T; Quast, U

    1975-02-01

    Evaluation of polished sections revealed the following: 1. Grain size in marginal areas of the crown is, in general, smaller than it is in the occlusal region. 2. Grain size varies depending on the casting method applied. Differences in hardness were found only to a limited extent. They were not always in line with the grain structure. This phenomenon deviating from the rule cannot satisfactorily be explained. The piping distribution was in accordance with observations made so far.

  19. Gating of Permanent Molds for ALuminum Casting

    Energy Technology Data Exchange (ETDEWEB)

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

    2004-03-30

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

  20. Clean Cast Steel Technology, Phase IV

    Energy Technology Data Exchange (ETDEWEB)

    Charles E. Bates

    2003-02-24

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

  1. Homogenity of Die Casting and Returning Material

    Directory of Open Access Journals (Sweden)

    J. Malik

    2012-04-01

    Full Text Available Homogeneity of die castings is influenced by wide range of technological parameters as piston velocity in filling chamber of die casting machine, filling time of mould cavity, temperature of cast alloy, temperature of the mould, temperature of filling chamber, surface pressure on alloy during mould filling, final pressure and others. Based on stated parameters it is clear, that main parameters of die casting are filling time of die mould cavity and velocity of the melt in the ingates. Filling time must ensure the complete filling of the mould cavity before solidification process can negatively influence it. Among technological parameters also belong the returning material, which ratio in charge must be constrained according to requirement on final homogeneity of die castings. With the ratio of returning material influenced are the mechanical properties of castings, inner homogeneity and chemical composition.

  2. Advanced casting technologies for lightweight automotive applications

    Directory of Open Access Journals (Sweden)

    Alan A. Luo

    2010-11-01

    Full Text Available This paper provides an overview of alloy and process developments in aluminum and magnesium castings for lightweight automotive applications. Wear-resistant aluminum alloys, creep-resistant and high strength/ductility magnesium alloys have been developed for automotive applications. On the process front, vacuum-assisted die casting and high vacuum die casting technologies have been developed for high-integrity body and chassis applications. Thin-wall and hollow casting components are being produced by low-pressure die casting processes for structural applications. Overcasting technology is gaining traction and has enabled mixed material designs for automotive sub-systems such as engine cradles and instrument panel beams. Simulation tools developed to predict the interfacial interactions of the dissimilar components and the structural integrity of the overcast systems are being validated in the casting trials.

  3. Chilling Tendency and Chill of Cast Iron

    Institute of Scientific and Technical Information of China (English)

    E. Fra(s); M. Górny; W. Kapturkiewicz; H. López

    2008-01-01

    An analytical expression is presented for the susceptibility of liquid cast iron to solidify according tothe Fe-C-X metastable system (also known as the chilling tendency of cast iron, CT). The analysis incorpo-rates the nucleation and growth processes associated with the eutectic transformation. The CT is related tothe physicochemical state of the liquid, the eutectic cells in the flake graphite, and the number of nodules innodular cast iron. In particular, the CT can be related to the critical wall thickness, Scr, or the chill width, Wcr,in wedge shaped castings. Finally, this work serves as a guide for understanding the effect of technical fac-tors such as the melt chemistry, the spheroidizing and inoculation practice, and the holding time and tam-perature on the resultant CT and chill of the cast iron. Theoretical calculations of Scr and Wcr compare wellwith experimental data for flake graphite and nodular cast iron.

  4. Method for casting thin metal objects

    Energy Technology Data Exchange (ETDEWEB)

    Pehrson, Brandon P; Moore, Alan F

    2015-04-14

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

  5. RESEARCH AND APPLICATION OF AS-CAST WEAR RESISTANCE HIGH CHROMIUM CAST IRON

    Institute of Scientific and Technical Information of China (English)

    1998-01-01

    The influence of alloy elements, such as boron and silicon, on the microstructure and properties of as-cast high chromium cast iron is studied. The results show that boron and silicon have a great effect on the mechanical properties and the wear resistance. Through proper addition of boron and silicon, the properties of as-cast high chromium cast iron can be improved effectively. Through analyzing the distribution of elements by scanning electron microscope, it has been shown that the addition of boron and silicon lowers the mass fraction of chromium saturated in as-cast austenite, and makes it unstable and liable to be transformed into martensite. The as-cast high chromium cast iron with proper content of boron and silicon is suitable for the manufacture of lining for asphalt concrete mixer and its wear resistance is 14 times that of lining made of low alloy white cast iron.

  6. Influence of Technological Parameters of Furane Mixtures on Shrinkage Creation in Ductile Cast Iron Castings

    Directory of Open Access Journals (Sweden)

    Vasková I.

    2014-10-01

    Full Text Available Ductile cast iron (GS has noticed great development in last decades and its boom has no analogue in history humankind. Ductile iron has broaden the use of castings from cast iron into areas, which where exclusively domains for steel castings. Mainly by castings, which weight is very high, is the propensity to shrinkage creation even higher. Shrinkage creation influences mainly material, construction of casting, gating system and mould. Therefore, the main realized experiment was to ascertain the influence of technological parameters of furane mixture on shrinkage creation in castings from ductile iron. Together was poured 12 testing items in 3 moulds forto determine and compare the impact of various technological parameters forms the propensity for shrinkage in the casting of LGG.

  7. COOLING METHOD OF SILUMINA CASTINGS AK15M3 AT VERTICAL CENTRIFUGAL CASTING

    Directory of Open Access Journals (Sweden)

    V. Yu. Stecenko

    2013-01-01

    Full Text Available The way of cooling of castings from silumin AK15M3 is developed at the vertical centrifugal casting, enabling to receive bimetallic blanks with high-disperse eutectic and hypereutectic microstructures and minimal allowance for machining.

  8. Newly developed vacuum differential pressure casting of thin-walled complicated Al-alloy castings

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The newly designed vacuum differential pressure casting (VDPC) unit was introduced, by which the capability of the VDPC process to produce thin-walled complicated Al-alloy castings, that are free from oxides, gas pore and shrinkage cavity and thus enhance overall part quality, was studied. Experimental results were compared with those of traditional gravity pouring and vacuum suction casting. The first series of experiments were focused on investigating the castability of thin section Al-alloy casting. In the second series of experiments the metallographic evidence, casting strength and soundness were examined. Finally, case studies of very interesting thin walled complicated casting applications were described. The advantages of the described technique have made possible to produce thin walled complicated Al-alloy casting (up to a section thickness of 1 mm), which is not practical for gravity pouring and vacuum suction casting.

  9. Development and application of titanium alloy casting technology in China

    Institute of Scientific and Technical Information of China (English)

    NAN Hai; XIE Cheng-mu; ZHAO Jia-qi

    2005-01-01

    The development and research of titanium cast alloy and its casting technology, especially its application inaeronautical industry in China are presented. The technology of molding, melting and casting of titanium alloy, casting quality control are introduced. The existing problems and development trend in titanium alloy casting technology are also discussed.

  10. Improved Foundry Castings Utilizing CAD/CAM

    Science.gov (United States)

    1981-10-01

    designed to simulate the heat transfer behavior during freezing and the subsequent cooling of an arbitrarily shaped 3D casting solidify- ing in a sand...variety of complex 2D and 3D geometries may be simulated by these routines. It is important, however, to be aware of the assumptions made in the design...three-dimensional with a sand mold surrounding a steel casting. The simulation program is desing - ed to simulate any shape. The shape of test casting

  11. Thermal gradient analysis of solidifying casting

    Directory of Open Access Journals (Sweden)

    J. Suchoń

    2008-08-01

    Full Text Available For description of casting solidification and crystallization process the thermal derivative analysis (TDA is commonly used. Besides the process kinetics considered in TDA method to describe the solidification process, the thermal gradient analysis can be also used for this purpose [1, 2]. In conducted studies analysis of thermal gradient distribution inside the solidifying wedge casting was shown which enabled determination of heat flow intensity on casting section.

  12. Theory of uniqueness of Indian Caste System

    OpenAIRE

    Kumar, Ashwin

    2006-01-01

    Classical studies on pre-modern Indian social structure have suggested apparent differences between the Indian caste system and social stratification as one can discern in other parts of the world. However, one needs to question such dogmatic assertions that such vast differences really existed. An endeavor is made in this research paper to reflect on the nature of caste hierarchy in pre-modern India. The caste system forms the significant basis of pre-modern Indian social structure. Early wr...

  13. Caste and wealth inequality in India

    OpenAIRE

    Zacharias, Ajit; Vakulabharanam, Vamsi

    2009-01-01

    In this paper, we conduct the novel exercise of analyzing the relationship between overall wealth inequality and caste divisions in India using nationally representative surveys on household wealth conducted during 1991–92 and 2002–03. According to our findings, the groups in India that are generally considered disadvantaged (known as Scheduled Castes or Scheduled Tribes) have, as one would expect, substantially lower wealth than the "forward" caste groups, while the Other Backward Classes an...

  14. Vacuum-sealed casting process under pressure

    Institute of Scientific and Technical Information of China (English)

    LI Chen-xi; GUO Tai-ming; WU Chun-jing; WANG Hong

    2006-01-01

    A new casting method, the vacuum-sealed mold casting under pressure, has been developed, and thin wall iron castings with high precision and smooth surface have been produced successfully with this casting method. The experimental results show that the liquid iron has a very excellent filling ability because a high negative pressure is formed in the mold cavity during filling process. The vacuum-sealed mold under pressure has very high compressive strength greater than 650 kPa, which is 3-4 times as high as that of the molds produced by high-pressure molding process or vacuum-sealed molding process.

  15. Cast functional accessories for heat treatment furnaces

    Directory of Open Access Journals (Sweden)

    A. Drotlew

    2010-10-01

    Full Text Available The study gives examples of the cast functional accessories operating in furnaces for the heat treatment of metals and alloys. The describeddesign solutions of castings and their respective assemblies are used for charge preparation and handling. They were put in systematicorder depending on furnace design and the technological purpose of heat treatment. Basic grades of austenitic cast steel, used for castings of this type, were enumerated, and examples of general guidelines formulated for their use were stated. The functional accessories described in this study were designed and made by the Foundry Research Laboratory of West Pomeranian University of Technology.

  16. Friction Stir Processing of Cast Superalloys Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This SBIR effort examines the feasibility of an innovative fabrication technology incorporating sand casting and friction stir processing (FSP) for producing...

  17. The temperature gradient on section of casting in process of primary crystallization of chromium cast iron

    Directory of Open Access Journals (Sweden)

    A. Studnicki

    2008-08-01

    Full Text Available The methodology of defining in article was introduced the temperature gradient in process of primary crystallization during cooling the casting from chromium cast iron on basis of measurements of thermal field in test DTA-K3. Insert also the preliminary results of investigations of influence temperature gradient on structure of studied wear resistance chromium cast iron.

  18. The temperature gradient on section of casting in process of primary crystallization of chromium cast iron

    OpenAIRE

    2008-01-01

    The methodology of defining in article was introduced the temperature gradient in process of primary crystallization during cooling the casting from chromium cast iron on basis of measurements of thermal field in test DTA-K3. Insert also the preliminary results of investigations of influence temperature gradient on structure of studied wear resistance chromium cast iron.

  19. Spray casting project final report

    Energy Technology Data Exchange (ETDEWEB)

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

    1996-08-01

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

  20. Control of Cast Iron Microstructure

    Science.gov (United States)

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

    1985-01-01

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

  1. Microdefects in cast multicrystalline silicon

    Energy Technology Data Exchange (ETDEWEB)

    Wolf, E.; Klinger, D.; Bergmann, S. [Inst. of Crystal Growth Berlin (Germany)

    1995-08-01

    The microdefect etching behavior of cast multicrystalline BAYSIX and SILSO samples is mainly the same as that of EFG silicon, in spite of the very different growth parameters applied to these two techniques and the different carbon contents of the investigated materials. Intentional decorating of mc silicon with copper, iron and gold did not influence the results of etching and with help of infrared transmission microscopy no metal precipitates at the assumed microdefects could be established. There are many open questions concerning the origin of the assumed, not yet doubtless proved microdefects.

  2. Yield Improvement in Steel Casting (Yield II)

    Energy Technology Data Exchange (ETDEWEB)

    Richard A. Hardin; Christoph Beckermann; Tim Hays

    2002-02-18

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

  3. Clean cast steel technology. Final report

    Energy Technology Data Exchange (ETDEWEB)

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

    1998-06-01

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

  4. PERFECTION OF TECHNOLOGY OF CASTINGS PRODUCTION TECHNOLOGY BY CONSUMABLE PATTERNS

    OpenAIRE

    N. I. Urbanovich; O. S. Komarov; V. I. Volosatikov; M. I. Kurbatov; V. G. Pavlovich

    2008-01-01

    The role of closed air gates at casting by gasified models of non-casting polystyrene in the process of castings defects elimination, connected with creation of non-gasified products of polystyrene thermodestruction, is studied.

  5. PERFECTION OF TECHNOLOGY OF CASTINGS PRODUCTION TECHNOLOGY BY CONSUMABLE PATTERNS

    Directory of Open Access Journals (Sweden)

    N. I. Urbanovich

    2008-01-01

    Full Text Available The role of closed air gates at casting by gasified models of non-casting polystyrene in the process of castings defects elimination, connected with creation of non-gasified products of polystyrene thermodestruction, is studied.

  6. Energy use in selected metal casting facilities - 2003

    Energy Technology Data Exchange (ETDEWEB)

    Eppich, Robert E. [Eppich Technologies, Syracuse, IN (United States)

    2004-05-01

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

  7. Technological parameters of die casting and quality of casting from EN AC46500 alloy

    Directory of Open Access Journals (Sweden)

    Š. Gašpár

    2016-07-01

    Full Text Available Die casting represents the highest technological level of metal mold casting. This technology enables production of almost all final products without necessity of further processing. The important aspect of efficiency and production is a proper casting parameters setting. In the submitted paper following die casting parameters are analyzed: plunger pressing speed and pressure. The studied parameters most significantly affect a qualitative of castings from EN AC46500 alloy and they influence the most a gained porosity level as well as basic mechanical properties represented by permanent deformations.

  8. Laboratory grey cast iron continuous casting line with electromagnetic forced convection support

    Directory of Open Access Journals (Sweden)

    J. Szajnar

    2010-07-01

    Full Text Available The article describes the construction of a 20 mm diameter grey cast iron ingots continuous casting laboratory line. This line is made ofthree main units: melting unit (induction furnace, casting unit and the pulling unit. In order to improve the homogeneity of themicrostructure of ingots (by applying forced convection of liquid metal during the crystallization process in this case a crystallizer system generating the forced movement of liquid metal based on a system of electrical power windings of the AC specific frequency. Thissolution allowed to obtain a homogeneous microstructure of the continuous casting of cast iron EN-GJL-200 species.

  9. DEVELOPMENTS IN THE FIELD OF STEEL AND CAST IRON

    Directory of Open Access Journals (Sweden)

    E. B. Ten

    2013-01-01

    Full Text Available The article describes the use of a number of promising casting technologies applied to produce the castings of steel and cast iron with special properties. Such as, technology of centrifugal casting of large-size workpieces made of steel, forecasting method composition of slag in the smelting of high-manganese steels, method of complex modifying chromium cast irons, analysis of properties of perspective high-alloy aluminium cast iron.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-11-24

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

  11. Theory of Cast Formation in Electrophoretic Deposition

    NARCIS (Netherlands)

    Biesheuvel, P. Maarten; Verweij, Henk

    1999-01-01

    The rate of cast formation in electrophoretic deposition is described by a combination of the equation of continuity for the suspension phase with expressions for the particle velocity and the movement of the cast-suspension boundary. The assumptions necessary to arrive at the well-known equations o

  12. Model castings with composite surface layer - application

    Directory of Open Access Journals (Sweden)

    J. Szajnar

    2008-10-01

    Full Text Available The paper presents a method of usable properties of surface layers improvement of cast carbon steel 200–450, by put directly in foundingprocess a composite surface layer on the basis of Fe-Cr-C alloy. Technology of composite surface layer guarantee mainly increase inhardness and aberasive wear resistance of cast steel castings on machine elements. This technology can be competition for generallyapplied welding technology (surfacing by welding and thermal spraying. In range of studies was made cast steel test castings withcomposite surface layer, which usability for industrial applications was estimated by criterion of hardness and aberasive wear resistance of type metal-mineral and quality of joint cast steel – (Fe-Cr-C. Based on conducted studies a thesis, that composite surface layer arise from liquid state, was formulated. Moreover, possible is control of composite layer thickness and its hardness by suitable selection of parameters i.e. thickness of insert, pouring temperature and solidification modulus of casting. Possibility of technology application of composite surface layer in manufacture of cast steel slide bush for combined cutter loader is presented.

  13. Geometric aspects of the casting process

    NARCIS (Netherlands)

    Ahn, H.-K.

    2002-01-01

    Manufacturing is the process of converting raw materials into useful products. Among the most important manufacturing processes, casting is a commonly used manufacturing process for plastic and metal objects. The industrial casting process consists of two stages. First, liquid is filled into a cavit

  14. Iron/Phosphorus Alloys for Continuous Casting

    Science.gov (United States)

    Dufresne, E. R.

    1986-01-01

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

  15. The quality of the joint between alloy steel and unalloyed cast steel in bimetallic layered castings

    Directory of Open Access Journals (Sweden)

    T. Wróbel

    2012-01-01

    Full Text Available In paper is presented technology of bimetallic layered castings based on founding method of layer coating directly in cast process so-called method of mould cavity preparation. Prepared castings consist two fundamental parts i.e. bearing part and working part (layer. The bearing part of bimetallic layered casting is typical foundry material i.e. ferritic-pearlitic unalloyed cast steel, whereas working part (layer is plate of austenitic alloy steel sort X2CrNi 18-9. The ratio of thickness between bearing and working part is 8:1. The aim of paper was assessed the quality of the joint between bearing and working part in dependence of pouring temperature and carbon concentration in cast steel. The quality of the joint in bimetallic layered castings was evaluated on the basis of ultrasonic non-destructive testing, structure and microhardness researches.

  16. Numerical modelling of stresses and deformations in casting processes

    DEFF Research Database (Denmark)

    Hattel, Jesper Henri

    1997-01-01

    Keywords: Stresses and deformations, casting, governing equations, thermal strain, control volume method......Keywords: Stresses and deformations, casting, governing equations, thermal strain, control volume method...

  17. Standard digital reference images for titanium castings

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2010-01-01

    1.1 The digital reference images provided in the adjunct to this standard illustrate various types and degrees of discontinuities occurring in titanium castings. Use of this standard for the specification or grading of castings requires procurement of the adjunct digital reference images, which illustrate the discontinuity types and severity levels. They are intended to provide the following: 1.1.1 A guide enabling recognition of titanium casting discontinuities and their differentiation both as to type and degree through digital radiographic examination. 1.1.2 Example digital radiographic illustrations of discontinuities and a nomenclature for reference in acceptance standards, specifications and drawings. 1.2 The digital reference images consist of seventeen digital files each illustrating eight grades of increasing severity. The files illustrate seven common discontinuity types representing casting sections up to 1-in. (25.4-mm). 1.3 The reference radiographs were developed for casting sections up to 1...

  18. Ferritic-austenitic cast steel - selected problems

    Directory of Open Access Journals (Sweden)

    Z. Stradomski

    2011-07-01

    Full Text Available The author has been involved in the problems occurring in the manufacture of ferritic-austenitic cast steel castings for many years. The author’s remarks and investigation results reported in this article will enable potential manufacturers to determine their own technical capabilities and structural determinants related to the chemical composition of material, which are crucial to the good quality of a casting. Particular emphasis should be laid on the role of enhanced carbon content, the presence of copper, the precipitates of the ζ phase, and the nature of solidification structure in the tendency of duplex-type cast steel to cracking. It seems that in view of the pro-ecological activities undertaken, including flue gas desulphurization in coal-fired power plants, efforts should be made in steel foundries to introduce selected grades of ferritic-austenitic cast steel to production.

  19. INDIAN CASTE SYSTEM: HISTORICAL AND PSYCHOANALYTIC VIEWS.

    Science.gov (United States)

    Vallabhaneni, Madhusudana Rao

    2015-12-01

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

  20. Possible segregation caused by centrifugal titanium casting.

    Science.gov (United States)

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

    1996-12-01

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

  1. Application of Integrated Database to the Casting Design

    Institute of Scientific and Technical Information of China (English)

    In-Sung Cho; Seung-Mok Yoo; Chae-Ho Lim; Jeong-Kil Choi

    2008-01-01

    Construction of integrated database including casting shapes with their casting design, technical knowledge, and thermophysical properties of the casting alloys were introduced in the present study. Recognition tech- nique for casting design by industrial computer tomography was used for the construction of shape database. Technical knowledge of the casting processes such as ferrous and non-ferrous alloys and their manufacturing process of the castings were accumulated and the search engine for the knowledge was developed. Database of thermophysical properties of the casting alloys were obtained via the experimental study, and the properties were used for .the in-house computer simulation of casting process. The databases were linked with intelligent casting expert system developed in center for e-design, KITECH. It is expected that the databases can help non casting experts to devise the casting and its process. Various examples of the application by using the databases were shown in the present study.

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

    Science.gov (United States)

    Singh, Rupinder; Singh, Harvir

    2016-04-01

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

  3. Characterization of Technetium Speciation in Cast Stone

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-11-11

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

  4. The X-ray Telescope of CAST

    OpenAIRE

    Kuster, M.; Bräuninger, H.; Cébrian, S.; Davenport, M.; Elefteriadis, C.; Englhauser, J.; Fischer, H.; Franz, J.; Friedrich, P.; R. Hartmann; Heinsius, F.H.; Hoffmann, D.H.H.; Hoffmeister, G.; Joux, J. N.; Kang, D.

    2007-01-01

    The Cern Axion Solar Telescope (CAST) is in operation and taking data since 2003. The main objective of the CAST experiment is to search for a hypothetical pseudoscalar boson, the axion, which might be produced in the core of the sun. The basic physics process CAST is based on is the time inverted Primakoff effect, by which an axion can be converted into a detectable photon in an external electromagnetic field. The resulting X-ray photons are expected to be thermally distributed between 1 and...

  5. CAST with its micromegas detector installed.

    CERN Multimedia

    Maximilien Brice

    2002-01-01

    The CERN Axion Solar Telescope (CAST) uses a prototype LHC dipole magnet to search for very weakly interacting neutral particles called axions, which should originate in the core of the Sun. The magnet converts the solar axions to photons which are then detected by an X-ray detector based on Micromegas technology. CAST's Micromegas detector has now been installed. Photos 01 02: General view of the CAST experiment with the Micromegas detector in place. Photo 03: Close-up of the micromegas set-up.

  6. Characteristics of cast and welded aluminium nodes

    Energy Technology Data Exchange (ETDEWEB)

    Oedegaard, J.; Polanco, M.; Syvertsen, F.; Sund, H. [SINTEF, Trondheim (Norway). Materials Technology

    2000-07-01

    It has been demonstrated that sand cast aluminium nodes can be produced with properties that gives competitive energy absorption capacity compared with welded aluminium nodes. Sand cast nodes could be mass-produced to a low cost and with properties that should be competitive to the properties of fusion welded nodes. This may open for simpler and more cost-effective joint alternatives when production of aluminium space-frames and subassemblies are in focus. Cast nodes joined to extruded members by adhesive bonding could be one example. (orig.)

  7. PHYSICAL SIMULATION OF CONTINUOUS ROLL CASTING PROCESS

    Institute of Scientific and Technical Information of China (English)

    L.H. Zhan; J. Zhong; X.Q. Li; M.H. Huang

    2005-01-01

    A series of simulating experimental studies on the rheological behavior and its influential factors of aluminum alloy in continuous roll-casting process have been explored in this paper with a Gleeble-1500 Thermal-Mechanical Simulation Tester and a set of special clamp system. Relevant rheological rules in the process of coupling transient solidification and continuous deformation of roll-casting conditions are obtained. Experimental results indicate that four different characteristic stages exist in the whole rheological process, and relative constitutive models suitable for the given conditions of continuous roll casting process have been established through multivariable linear regression analysis of the experimental data.

  8. Optimization of the Chemical Composition of Cast Iron Used for Casting Ball Bearing Grinding Disks

    Institute of Scientific and Technical Information of China (English)

    Aurel Crisan; Sorin Ion; Munteanu; Ioan Ciobanu; Iulian Riposan

    2008-01-01

    The chemical composition of cast iron used for casting ball bearing machining disks was varied to optimize the properties such as castability, hardenability, and durability in ball machining. The cast iron characteristics were most strongly dependent on the Ni content and the carbon saturation degree, So. This paper describes the types of test specimens, the working conditions, and the experimental results. The in-crease of the degree of carbon saturation reduces the tendency to form shrinkholes in the castings. The de-crease in the Ni content negatively affects the final hardening treatment. A way to control solidification de-fects in cast iron, by reducing the Ni content, has been verified on cast disks.

  9. 49 CFR 192.275 - Cast iron pipe.

    Science.gov (United States)

    2010-10-01

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

  10. Laboratory grey cast iron continuous casting line with electromagnetic forced convection support

    OpenAIRE

    2010-01-01

    The article describes the construction of a 20 mm diameter grey cast iron ingots continuous casting laboratory line. This line is made ofthree main units: melting unit (induction furnace), casting unit and the pulling unit. In order to improve the homogeneity of themicrostructure of ingots (by applying forced convection of liquid metal during the crystallization process) in this case a crystallizer system generating the forced movement of liquid metal based on a system of electrical power win...

  11. Dimensional accuracy of small gold alloy castings. Part 4. The casting ring and ring liners.

    Science.gov (United States)

    Morey, E F

    1992-04-01

    The role of the casting ring and its asbestos liner is discussed. Asbestos as a liner has now largely been replaced by two alternative materials, one based on cellulose and the other on ceramic fibres. The limited literature on the effect of these newer materials on casting accuracy is also reviewed as their introduction may require significant changes in the traditional technology of dental casting.

  12. Investigations of Protective Coatings for Castings of High-manganese Cast Steels

    Directory of Open Access Journals (Sweden)

    M. Holtzer

    2013-01-01

    Full Text Available When cast steel castings are made in moulding sands on matrices of high-silica sand, which has a low fire resistance the problem of theso-called chemical penetration is distinctly visible. Whereas this effect appears to a small degree only when moulding sand matrices are of chromite, zircon or olivine sands. Therefore in case of making castings of high-manganese cast steel (e.g. Hadfield steel sands not containing free silica should be applied (e.g. olivine sand or in case of a high-silica matrix protective coatings for moulds and cores should be used. Two protective coatings, magnesite alcoholic (marked as coating 1 and coating 2 originated from different producers and intended for moulds for castings of the Hadfield steel, were selected for investigations. Examinations of the basic properties were performed for these coatings: viscosity, thermal analysis, sedimentation properties, wear resistance. In order to estimate the effectiveness of protective coatings the experimental castings were prepared. When applying coating 1, the surface quality of the casting was worse and traces of interaction between the casting material (cast steel and the coating were seen. When protective coating 2 was used none interactions were seen and the surface quality was better.

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

    Science.gov (United States)

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

    1997-01-01

    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.

  14. Centrifugal Casting of High Speed Steel/Nodular Cast Iron Compound Roll Collar

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The centrifugal casting of compound HSS/nodular cast iron roll collar was studied, and the factors affecting transition zone quality were analyzed. The pouring temperature and interval in pouring are the main factors affecting transition zone quality. By controlling process parameter and flux adding during casting, high quality roll collar was obtained. The cause, why in the casting of HSS part, segregation appears easily, was analyzed and the countermeasure eliminating segregation was put forward, the measure eliminating heat treatment crackling was also put forward.

  15. Alumina Carbon Refractory Products for Continuous Casting

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ 1 Scope This standard specifies the classification.techni-cal requirements,test methods,inspection rules,packing,marking,transportation,storage and quality certificate of alumina carbon refractory products for continuous casting.

  16. ToxCast/ToxRefDB

    Data.gov (United States)

    U.S. Environmental Protection Agency — ToxCast is used as a cost-effective approach for efficiently prioritizing the toxicity testing of thousands of chemicals. It uses data from state-of-the-art high...

  17. Cast Care: Do's and Don'ts

    Science.gov (United States)

    ... has a fiberglass cast that's lined with a water-repellent liner, it's probably OK for him or her ... opportunities Reprint Permissions A single copy of these materials may be reprinted for noncommercial personal use only. " ...

  18. Caste in India, Past and Present

    Science.gov (United States)

    Bishop, Donald H.

    1971-01-01

    Traced is the sociocultural framework for the system in Indian culture which emphasized duty and obligations rather than individual freedom and rights. Also discussed are contemporary changes in the caste system. (DB)

  19. Theory of uniqueness of Indian Caste System

    Directory of Open Access Journals (Sweden)

    Ashwin Kumar

    2006-08-01

    Full Text Available Classical studies on pre-modern Indian social structure have suggested apparent differences between the Indian caste system and social stratification as one can discern in other parts of the world. However, one needs to question such dogmatic assertions that such vast differences really existed. An endeavor is made in this research paper to reflect on the nature of caste hierarchy in pre-modern India. The caste system forms the significant basis of pre-modern Indian social structure. Early writers conceived the caste system of pre-modern India as something unique to India. An attempt is made to question this application of theory of uniqueness in the case of India.

  20. Theory of uniqueness of Indian Caste System

    Directory of Open Access Journals (Sweden)

    Ashwin Kumar

    2005-11-01

    Full Text Available Classical studies on pre-modern Indian social structure have suggested apparent differences between the Indian caste system and social stratification as one can discern in other parts of the world. However, one needs to question such dogmatic assertions that such vast differences really existed. An endeavor is made in this research paper to reflect on the nature of caste hierarchy in pre-modern India. The caste system forms the significant basis of pre-modern Indian social structure. Early writers conceived the caste system of pre-modern India as something unique to India. An attempt is made to question this application of theory of uniqueness in the case of India.

  1. Rare Earth Additions in Continuously Cast Steel

    Science.gov (United States)

    Wilson, William G.; Heaslip, L. J.; Sommerville, I. D.

    1985-09-01

    Rare earth (lanthanide metals) addiiions to continuously cast steel are particularly advantageous because of their ability to refine as-cast structures, reduce segregation and increase hot ductility at temperatures just below that of solidification. The complete shape control of sulfides in steels containing Rare Earth Metals (REM), whether continuously cast or ingot cast, is primarily responsible for improvements in ductility related mechanical properties, weldability, fatigue resistance and resistance to hydrogen damage. Complete sulfide shape control can be obtained with REM additions at sulfur levels as high as.020%. The greatest improvements, however, are obtained with REM additions to low sulfur steels. However, to achieve full operational advantages afforded by REM, nozzle blockage problems must be circumvented. Water model studies indicate a possible solution.

  2. Friction Stir Processing of Cast Superalloys Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This SBIR Phase I effort examines the feasibility of an innovative fabrication technology incorporating sand casting and friction stir processing (FSP) for producing...

  3. Advanced lost foam from casting technology

    Energy Technology Data Exchange (ETDEWEB)

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

    1996-05-01

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

  4. Fabrication of bulk metallic glasses by centrifugal casting method

    OpenAIRE

    R. Nowosielski; R. Babilas

    2007-01-01

    Purpose: The aim of the present work is characterization of the centrifugal casting method, apparatus andproduced amorphous materials, which are also known as bulk metallic glassesDesign/methodology/approach: The studied centrifugal casting system consists of two main parts: castingapparatus and injection system of molten alloy. The described centrifugal casting method was presented bypreparing a casting apparatus “CentriCast – 5”. The apparatus includes a cylindrical copper mold, which isrot...

  5. Strip Casting of High Performance Structural Alloys

    Institute of Scientific and Technical Information of China (English)

    S S Park; J G Lee; Nack J Kim

    2004-01-01

    There exists a great need for the development of high performance alloys due to increasing demands for energy conservation and environmental protection. Application of strip casting shows a strong potential for the improvement of properties of existing alloys and also for the development of novel alloy systems with superior properties. The present paper reviews our Center's activities in the development of high performance alloys by strip casting. Examples include (1) Al alloys, (2) wrought Mg alloys, and (3) bulk metallic glass (BMG) alloys.

  6. Casting Technology Development for SFR Metallic Fuel

    Energy Technology Data Exchange (ETDEWEB)

    Lee, C.T.; Oh, S.J.; Ryu, H.J.; Kim, K.H.; Lee, Y.S.; Kim, S.K.; Woo, Y.M.; Ko, Y.M.; Lee, C.B. [KAERI, 150 Deokjin-dong, Yuseong, Daejeon, 305-353 (Korea, Republic of)

    2009-06-15

    Fabrication technology of metallic fuel for sodium fast reactor (SFR) is being developed in Korea as a national mid- and long-term nuclear R and D program from 2007. The metallic fuel for SFR should be remotely fabricated under a radiation shielded environment such as a glove box or hot cell, because it contains long-lived minor actinides such as Np, Am and Cm. In order to design a reliable remote fabrication system, various casting techniques have been studied by using U-Zr and U-Zr-RE alloys as surrogate fuel material. Rare earth elements such as Ce or Nd were used as a surrogate for minor actinide elements or solid solution fission products. Macro-scale soundness, microstructures and compositional homogeneity of metallic fuel samples fabricated by vacuum-assisted injection casting, vacuum-assisted gravity casting, centrifugal atomization and continuous casting were compared. Although sound slugs of U-Zr metallic fuel of 4{approx}6 mm in diameter could be fabricated by vacuum-assisted injection casting or vacuum-assisted gravity casting, it was necessary to consider that vaporization of Am and volume of radioactive wastes such as crucibles and molds should be minimized. Effects of casting parameters on the volatile loss, and effects of coatings on the chemical reaction between metallic fuel and molds are discussed. Some methods to reduce the volatile Am loss and waste molds and crucibles will be proposed. Short rods of U-Zr or U-Zr-Ce fuel will be fabricated by the vacuum-assisted gravity casting technique for an irradiation test in the HANARO research reactor from 2010. (authors)

  7. CAST Xi'an Branch Established

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ China Academy of Space Technology (CAST) Xi'an Branch was established on April 8,2008.The new branch consists of the headquarters of the former Xi'an Institute of Space Radio Technology (XISRT) of CAST and five former subsidiaries of the XISRT,i.e.the Institute of Space Electronic Technology,the Institute of Microwave Technology,the Institute of Space Antenna Technology,the Manufacturing Center for Space Electronics and Civilian High-tech Company.

  8. Combination Of Investment And Centrifugal Casting

    Science.gov (United States)

    Creeger, Gordon A.

    1994-01-01

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

  9. Casting Process Developments for Improving Quality

    Science.gov (United States)

    El-Mahallawy, Nahed A.; Taha, Mohamed A.

    1985-09-01

    This paper presents a short synopsis of the important developments in casting/solidification processes, as well as the important advances in the conventional methods. These developments are discussed related to quality aspects. The position of each process with respect to practice, as well as expected gains in cost, are examined. The paper briefly features the author's work on innovative processes (directional solidification, rheocasting, squeeze-casting and rapid solidification) as well as work of other investigators on developments in conventional methods.

  10. Latest results of cast and future prospects

    CERN Document Server

    Vafeiadis, Theodoros

    2014-01-01

    CERN Axion Solar Telescope (CAST) is currently the most sensitive axion helioscope designed to search for axions and axion-like particles produced in the Sun. CAST completed successfully the second part of CAST phase II where the magnet bores were lled with 3He gas at variable pressure scanning axion masses up to 1.2 eV In the absence of signal it has set the best experimental limit on the axion-photon coupling constant over a broad range of axion masses. In 2013 CAST has improved its sensitivity to solar axions with rest mass below 0.02 eV by upgrading the Micromegas detectors and it will continue in 2014 with the implementation of a second X-ray optic and a new type detector (InGRID). In addition, CAST has extended its sensitivity into the sub-keV energy range using a silicon detector (SDD), to search for solar chameleons. Thus, CAST also became sensitive to dark energy particles. A new generation axion helioscope (IAXO) aims to improve the current axion-photon coupling by 1-1.5 orders of magnitude. This wi...

  11. Microbiological Study of Cast Posts before Cementation

    Directory of Open Access Journals (Sweden)

    Maricela Vallejo-Labrada

    2017-01-01

    Full Text Available This study identifies the most common microorganisms present in type III gold cast posts related to pulpal disease and evaluates the sterilization/disinfection method before cementation in the root canal. Forty-five type III gold cast posts were aseptically collected in sterile sealed plastic bags and taken to the microbiology laboratory to carry out the study: fifteen cast posts had no treatment, fifteen were disinfected (immersion in 70% alcohol during 15 minutes, and fifteen were autoclaved at 121°C for 15 minutes by using saturated steam under 15 psi pressure. By using a two-proportion z-test, the difference was statistically significant (p>0.05 and demonstrates that, in spite of the aseptic pattern used in the cast post collection and laboratory procedures, some cast posts arrive contaminated at the consulting office. The disinfection process worked out in a high percentage and demonstrated that the sterilization by autoclaving eliminated completely the pathogenic microbiota without affecting the cast post shape and integrity that could compromise their final fitting.

  12. Microbiological Study of Cast Posts before Cementation

    Science.gov (United States)

    Ojeda-Garces, Juan Carlos

    2017-01-01

    This study identifies the most common microorganisms present in type III gold cast posts related to pulpal disease and evaluates the sterilization/disinfection method before cementation in the root canal. Forty-five type III gold cast posts were aseptically collected in sterile sealed plastic bags and taken to the microbiology laboratory to carry out the study: fifteen cast posts had no treatment, fifteen were disinfected (immersion in 70% alcohol during 15 minutes), and fifteen were autoclaved at 121°C for 15 minutes by using saturated steam under 15 psi pressure. By using a two-proportion z-test, the difference was statistically significant (p > 0.05) and demonstrates that, in spite of the aseptic pattern used in the cast post collection and laboratory procedures, some cast posts arrive contaminated at the consulting office. The disinfection process worked out in a high percentage and demonstrated that the sterilization by autoclaving eliminated completely the pathogenic microbiota without affecting the cast post shape and integrity that could compromise their final fitting.

  13. Low Background Micromegas in CAST

    CERN Document Server

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

    2015-01-01

    Solar axions could be converted into x-rays inside the strong magnetic field of an axion helioscope, triggering the detection of this elusive particle. Low background x-ray detectors are an essential component for the sensitivity of these searches. We report on the latest developments of the Micromegas detectors for the CERN Axion Solar Telescope (CAST), including technological pathfinder activities for the future International Axion Observatory (IAXO). The use of low background techniques and the application of discrimination algorithms based on the high granularity of the readout have led to background levels below 10$^{-6}$ counts/keV/cm$^2$/s, more than a factor 100 lower than the first generation of Micromegas detectors. The best levels achieved at the Canfranc Underground Laboratory (LSC) are as low as 10$^{-7}$ counts/keV/cm$^2$/s, showing good prospects for the application of this technology in IAXO. The current background model, based on underground and surface measurements, is presented, as well as ...

  14. Last cast for the LHC

    CERN Multimedia

    2005-01-01

    The first major contract signed for the LHC is drawing to a close. Belgian firm Cockerill Sambre (a member of the Arcelor Group) has just completed production of 50,000 tonnes of steel sheets for the accelerator's superconducting magnet yokes, in what has proved to be an exemplary partnership with CERN. Philippe Lebrun, Head of the AT Department, Lyn Evans, LHC Project Leader, and Lucio Rossi, Head of the AT-MAS Group, in front of the last batch of steel for the LHC at Cockerill Sambre. It was a bright red-letter day at the end of May, when Belgian firm Cockerill Sambre of the Arcelor Group marked the completion of one of the largest contracts for the LHC machine by casting the last batch of steel sheets for the LHC superconducting magnet yokes in the presence of LHC Project Leader Lyn Evans, AT Department Head Philippe Lebrun, Magnets and Superconductors (AT-MAS) Group Leader Lucio Rossi and Head of the AT-MAS Group's components centre Francesco Bertinelli. The yokes constitute approximately 80% of the acc...

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

    Science.gov (United States)

    Stoddard, Nathan G.

    2011-11-01

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

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

    Science.gov (United States)

    Stoddard, Nathan G

    2014-01-14

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

  17. Mechanical properties of homogenized twin-roll cast and conventionally cast AZ31 magnesium alloys

    Directory of Open Access Journals (Sweden)

    Mariia Zimina

    2015-02-01

    Full Text Available The improvement of mechanical properties of magnesium alloys nowadays is very important, because of the variety of industrial applications. For this goal, the number of casting techniques and further treatments were developed. Among the continuous casting techniques, which allow producing long strips of the alloys, is twin-roll casting. Using this process one can get the magnesium alloy with finest microstructure and higher specific strength. In this paper the comparison of tensile properties of conventionally cast and twin-roll cast AZ31 magnesium alloys was made. Tensile tests were carried out with constant strain rate 10-3 s-1 at temperatures ranging from 100 to 300 °C. Both materials were tested in as-cast state and after homogenization treatment at 450 °C for 10 hours. The investigation showed that there are no significant changes in ductility of AZ31 conventionally cast alloy even after heat treatment, while the ductility of twin-roll cast alloy increases.

  18. FORMATION OF WEAR-RESISTANT CHROMIUM CAST IRON CASTING INTO THE CHILL MOLD

    Directory of Open Access Journals (Sweden)

    E. I. Marukovich

    2013-01-01

    Full Text Available The analysis of thermal processes of formation of castings from wearproof chromic cast irons for replaceable details of centrifugal mills and crushers is carried out. Influence of protective and dividing coverings on intensity of heating of the chill mold is investigated.

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

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, D. [University of Northern Iowa, Cedar Falls, IA (United States). Dept. of Industrial Technology] [comp.

    1994-06-01

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

  20. Precision Casting via Advanced Simulation and Manufacturing

    Science.gov (United States)

    1997-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

    Sabau, Adrian S [ORNL

    2005-09-01

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

  2. Colour Metallography of Cast Iron - Chapter 3: Spheroidal Graphite Cast Iron (Ⅰ

    Directory of Open Access Journals (Sweden)

    Zhou Jiyang

    2010-02-01

    Full Text Available Cast iron, as a traditional metal material, has advantages of low total cost, good castability and machinability, good wear resistance and low notch sensitivity, and is still facing tough challenge in quality, property and variety of types etc. Experts and engineers studying and producing iron castings all around world extremely concern this serious challenge. Over more than 30 years, a great of research work has been carried out on how to further improve its property, expand its application and combine cast iron technology with some hi-techs (for example, computer technology. Nevertheless, cast iron is a multi-element and multi-phase alloy and has complex and variety of structures and still has great development potential in structure and property. For further studying and developing cast iron, theoretical research work is important promise, and the study on solidification process and control mechanism of graphite morphology is fundamental for improving property of cast iron and developing new type of cast iron. Metallography of cast iron normally includes two sections: liquid phase transformation and solid phase transformation. The book, Colour Metallography of Cast Iron, uses colour metallography technique to study solidification structures of cast irons: graphite, carbides, austenite and eutectics; and focuses on solidification processes. With progress of modern solidification theory, the control of material solidification process becomes important measure for improving traditional materials and developing new materials. Solidification structure not only influences mechanical and physical properties of cast iron, but also affects its internal quality. The book uses a large amount of colour photos to describe the formation of solidification structures and their relations. Crystallization phenomena, which cannot be displayed with traditional metallography, are presented and more phase transformation information is obtained from these colour

  3. Evaluation of porosity in Al alloy die castings

    Directory of Open Access Journals (Sweden)

    M. Říhová

    2012-01-01

    Full Text Available Mechanical properties of an Al-alloy die casting depend significantly on its structural properties. Porosity in Al-alloy castings is one of the most frequent causes of waste castings. Gas pores are responsible for impaired mechanical-technological properties of cast materials. On the basis of a complex evaluation of experiments conducted on AlSi9Cu3 alloy samples taken from the upper engine block which was die- cast with and without local squeeze casting it can be said that castings manufactured without squeeze casting exhibit maximum porosity in the longitudinal section. The area without local squeeze casting exhibits a certain reduction in mechanical properties and porosity increased to as much as 5%. However, this still meets the norms set by SKODA AUTO a.s.

  4. Gating Systems for Sizeable Castings from Al Alloys Cast into Ceramic Moulds

    Directory of Open Access Journals (Sweden)

    I. Stachovec

    2012-04-01

    Full Text Available In contrast to casting to conventional non-reusable “sand” moulds, for which calculating technique for an optimum design of the gating system is comparatively well-developed, a trial-and-error method is applied mostly for casting to ceramic shell moulds made by the investment casting technology. A technologist selects from gating systems of several types (that are standardized by the foundry mostly on the basis of experience. However, this approach is not sustainable with ever growing demands on quality of castings and also the economy of their fabrication as well as with new types of complex sizeable castings introduced to the production gradually (by new customers from the aircraft industry above all any more. The simulation software may be used as a possible tool for making the process of optimising gating systems more effective.

  5. Unique morphology of intratubular light chain casts in multiple myeloma: The amyloid cast nephropathy

    Directory of Open Access Journals (Sweden)

    Alok Sharma

    2014-01-01

    Full Text Available Cast nephropathy is the most frequent pattern of renal involvement in multiple myeloma characterized by presence of tubular casts with characteristic morphology that are composed of monotypic (either kappa or lambda light chains as seen by immunofluorescence microscopy. Rarely these casts may show evidence of amyloidogenesis and assume a unique morphology, which needs to be appreciated for arriving at accurate diagnosis. We present the case of an elderly male presenting with features of acute kidney injury and detected with extensive inspissation of intratubular casts with lambda light chain restriction and a unique morphology with spiculated congophilic periphery. Further investigations confirmed the presence of systemic myeloma. Presence of intratubular amyloid casts is a rare occurrence which needs to be recognized by the pathologist and forms a vital element in timely diagnosis of the systemic disease which often presents with renal involvement.

  6. Mechanism and application of a newly developed pressure casting process: horizontal squeeze casting

    Directory of Open Access Journals (Sweden)

    Li Peijie

    2014-07-01

    Full Text Available Compared to traditional high-pressure die casting (HPDC, horizontal squeeze casting (HSC is a more promising way to fabricate high-integrity castings, owing to a reduced number of gas and shrinkage porosities produced in the casting. In this paper, the differences between HSC and HPDC are assessed, through which it is shown that the cavity filling velocity and the size of the gating system to be the most notable differences. Equipment development and related applications are also reviewed. Furthermore, numerical simulation is used to analyze the three fundamental characteristics of HSC: slow cavity filling, squeeze feeding and slow sleeve filling. From this, a selection principle is given based on the three related critical casting parameters: cavity filling velocity, gate size and sleeve filling velocity. Finally, two specific applications of HSC are introduced, and the future direction of HSC development is discussed.

  7. Applying RP-FDM Technology to Produce Prototype Castings Using the Investment Casting Method

    Directory of Open Access Journals (Sweden)

    M. Macků

    2012-09-01

    Full Text Available The research focused on the production of prototype castings, which is mapped out starting from the drawing documentation up to theproduction of the casting itself. The FDM method was applied for the production of the 3D pattern. Its main objective was to find out whatdimensional changes happened during individual production stages, starting from the 3D pattern printing through a silicon mouldproduction, wax patterns casting, making shells, melting out wax from shells and drying, up to the production of the final casting itself.Five measurements of determined dimensions were made during the production, which were processed and evaluated mathematically.A determination of shrinkage and a proposal of measures to maintain the dimensional stability of the final casting so as to meetrequirements specified by a customer were the results.

  8. Analysis of the structure of castings made from chromium white cast iron resistant to abrasive wear

    Directory of Open Access Journals (Sweden)

    D. Kopyciński

    2009-10-01

    Full Text Available It has been proved that an addition of boron carbide and disintegrated steel scrap introduced as an inoculant to the chromium white cast iron changes the structure of castings. The said operation increases the number of crystallization nuclei for dendrites of the primary austenite. In this case, the iron particles act as substrates for the nucleation of primary austenite due to a similar crystallographic lattice. The more numerous are the dendrites of primary austenite and the structure more refined and the mechanical properties higher. Castings after B4C inoculation revealed a different structure of fine grained fracture. Primary precipitates of chromium carbide also appeared, reducing the mechanical properties of as-cast parts. Properly established heat treatment regime makes chromium iron castings regain their, originally high, mechanical properties.

  9. Mechanism and application of a newly developed pressure casting process:horizontal squeeze casting

    Institute of Scientific and Technical Information of China (English)

    Li Peijie; Huang Xiusong; He Liangju; Liu Xiangshang; Wang Benci

    2014-01-01

    Compared to traditional high-pressure die casting (HPDC), horizontal squeeze casting (HSC) is a more promising way to fabricate high-integrity castings, owing to a reduced number of gas and shrinkage porosities produced in the casting. In this paper, the differences between HSC and HPDC are assessed, through which it is shown that the cavity ifling velocity and the size of the gating system to be the most notable differences. Equipment development and related applications are also reviewed. Furthermore, numerical simulation is used to analyze the three fundamental characteristics of HSC: slow cavity ifling, squeeze feeding and slow sleeve ifling. From this, a selection principle is given based on the three related critical casting parameters: cavity filling velocity, gate size and sleeve ifling velocity. Finaly, two speciifc applications of HSC are introduced, and the future direction of HSC development is discussed.

  10. The deformation of wax patterns and castings in investment casting technology

    Directory of Open Access Journals (Sweden)

    A. Herman

    2012-01-01

    Full Text Available The dimensional accuracy of the final casting of Inconel alloy 738 LC is affected by many aspects. One of them is the choice of method and time of cooling wax model for precision investment casting. The main objective was to study the initial deformation of the complex shape of the casting of the rotor blades. Various approaches have been tested for cooling wax pattern. When wax models are cooling on the air, without clamping in jig for cooling, deviations from the ideal shape of the casting are very noticeable (up to 8 mm and most are in extreme positions of the model. When blade is cooled in fixing jig in water environment, the resulting deviations compared with cooling in air are significantly larger, sometimes up to 10 mm. This itself does not mean that the final shape of the casting is dimensionally more accurate with usage of wax models, which have deviations from the ideal position smaller. Another deformation occurs when shell mould is produced around wax pattern and furthermore deformations emerge while casting of blade is cooling. This paper demonstrates first steps in describing complex process of deformations of Inconel alloy blades produced with investment casting technology by comparing results from thermal imagery, simulations in foundry simulation software ProCAST 2010 and measurements from CNC scanning system Carl Zeiss MC 850. Conclusions are so far not groundbreaking, but it seems deformations of wax pattern and deformations of castings do in some cases cancel each other by having opposite directions. Describing entirely whole process of deformations will help increase precision of blade castings so that models at the beginning and blades in the end are the same.

  11. Effect of casting parameters and deformation on microstructure evolution of twin-roll casting magnesium alloy AZ31

    Institute of Scientific and Technical Information of China (English)

    JU Dong-ying; HU Xiao-dong

    2006-01-01

    Twin roll casting method is a promising route to directly produce magnesium alloy strip. It is a rapid solidification process with high temperature gradient combined with thermal flow and rolling deformation in the casting region. As-cast strip with proper microstructure is requested to serve as next rolling feedstock. However the microstructure of as-cast strip is sensitive for casting conditions during the casting process and the as-cast microstructure greatly affects the mechanical properties. In this work,the effect of casting speed,pouring temperature,deformation as well as anneal process on microstructure and mechanical properties were investigated. The results revels that twin-roll casting process can effectively refine the grain size,improve the morphology and distribution states of Mg17Al12. The homogenization treatment time can be shorted for the fine microstructure and lower the cost dramatically for the next forming process.

  12. Influences of Casting Pressure Conditions on the Quality and Properties of a Magnesium Cylinder Head Cover Die Casting

    Institute of Scientific and Technical Information of China (English)

    Wenhui LIU; Yangai LIU; Shoumei XIONG; Baicheng LIU; Y. Matsumoto; M. Murakami

    2005-01-01

    Casting pressure conditions have great influences on the casting defects, such as gas porosity, shrinkage porosity and gas holes. A Mg cylinder head cover die casting was used to experimentally study the influences of casting pressure,the loading time and the piston position of pressure intensification on the variation of pressure and the quality of casting. The results show that casting pressure, the loading time and the piston position of pressure intensification have great influences on the pressure variations in the mold, the quality and performance of casting. The external quality, the density and the tensile strength of casting were improved with the increase of casting pressure and the piston position of pressure intensification and the decrease of the loading time of pressure intensification.

  13. Computer simulation for centrifugal mold filling of precision titanium castings

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    Computer simulation codes were developed based on a proposed mathematical model for centrifugal mold filling processes and previous computer software for 3D mold filling and solidification of castings (CASM-3D for Windows). Sample simulations were implemented for mold filling processes of precision titanium castings under gravity and different centrifugal casting techniques. The computation results show that the alloy melt has a much stronger mold filling ability for thin section castings under a centrifugal force field than that only under the gravity. A "return back" mold filling manner is showed to be a reasonable technique for centrifugal casting processes, especially for thin section precision castings.

  14. Production of carbide-free thin ductile iron castings

    Institute of Scientific and Technical Information of China (English)

    M. Ashraf Sheikh

    2008-01-01

    The fast cooling rate of thin ductile iron castings requires special consideration to produce carbide-free castings. Extraor-dinary care was taken to select the charge to produce castings of 100-mm long round bars with 16-ram diameter. The castings show the presence of carbides in the bars. Seven melts were made with different temperatures and with different compositions to get rid of carbides. After chemical analyses, it was found that the extra purity of the charge with less than 0.008wt% sulfur in the castings was the cause of carbides. To remove the carbides fi'om the castings, sulfur should be added to the charge.

  15. The X-ray Telescope of CAST

    CERN Document Server

    Kuster, M; Cebrián, S; Davenport, M; Elefteriadis, C; Englhauser, J; Fischer, H; Franz, J; Friedrich, P; Hartmann, R; Heinsius, F H; Hoffmann, Dieter H H; Hoffmeister, G; Joux, J N; Königsmann, K C; Kang, D; Kotthaus, R; Lasseur, C; Lippitsch, A; Lutz, G; Morales, J; Papaevangelou, T; Rodríguez, A; Strüder, L; Vogel, J; Zioutas, K

    2007-01-01

    The Cern Axion Solar Telescope (CAST) is in operation and taking data since 2003. The main objective of the CAST experiment is to search for a hypothetical pseudoscalar boson, the axion, which might be produced in the core of the sun. The basic physics process CAST is based on is the time inverted Primakoff effect, by which an axion can be converted into a detectable photon in an external electromagnetic field. The resulting X-ray photons are expected to be thermally distributed between 1 and 7 keV. The most sensitive detector system of CAST is a pn-CCD detector combined with a Wolter I type X-ray mirror system. With the X-ray telescope of CAST a background reduction of more than 2 orders off magnitude is achieved, such that for the first time the axion photon coupling constant g_agg can be probed beyond the best astrophysical constraints g_agg < 1 x 10^-10 GeV^-1.

  16. The x-ray telescope of CAST

    Science.gov (United States)

    Kuster, M.; Bräuninger, H.; Cebrián, S.; Davenport, M.; Eleftheriadis, C.; Englhauser, J.; Fischer, H.; Franz, J.; Friedrich, P.; Hartmann, R.; Heinsius, F. H.; Hoffmann, D. H. H.; Hoffmeister, G.; Joux, J. N.; Kang, D.; Königsmann, K.; Kotthaus, R.; Papaevangelou, T.; Lasseur, C.; Lippitsch, A.; Lutz, G.; Morales, J.; Rodríguez, A.; Strüder, L.; Vogel, J.; Zioutas

    2007-06-01

    The CERN Axion Solar Telescope (CAST) has been in operation and taking data since 2003. The main objective of the CAST experiment is to search for a hypothetical pseudoscalar boson, the axion, which might be produced in the core of the sun. The basic physics process CAST is based on is the time inverted Primakoff effect, by which an axion can be converted into a detectable photon in an external electromagnetic field. The resulting x-ray photons are expected to be thermally distributed between 1 and 7 keV. The most sensitive detector system of CAST is a pn-CCD detector combined with a Wolter I type x-ray mirror system. With the x-ray telescope of CAST a background reduction of more than 2 orders of magnitude is achieved, such that for the first time the axion photon coupling constant gaγγ can be probed beyond the best astrophysical constraints gaγγ < 1 × 10-10 GeV-1.

  17. CASTing light on dark matter particles

    CERN Multimedia

    2005-01-01

    CERN's CAST collaboration recently released first results from its search for solar axions, a candidate dark matter particle. Though they haven't found any axions yet, they have done much to narrow the hunt. The CAST experiment. Physicists think the universe is permeated with dark matter, particles that don't emit or absorb radiation and so are invisible to traditional telescopes. So far no one has found direct signs of dark matter. A different breed of telescope, however, may be able to see such particles. CERN's Axion Solar Telescope (CAST), currently the world's only working axion helioscope, is a superconducting test magnet from the Large Hadron Collider (LHC) that has been refurbished and outfitted with X-ray detectors, plus a focusing mirror system for X-rays that was recovered from the German space program. CAST stares into the sun in search of particles called axions, one of the leading candidates for dark matter. On 9 November, the CAST collaboration released the results of their first experimen...

  18. Land-based turbine casting initiative

    Energy Technology Data Exchange (ETDEWEB)

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

    1995-10-01

    The Advanced Turbine Systems (ATS) program has set goals which include a large-scale utility turbine efficiency that exceeds 60 percent (LHV) on natural gas and an industrial turbine system heat rate improvement of 15 percent. To meet these goals, technological advances developed for aircraft gas turbine engines need to be applied to land based gas turbines. These technological advances include: directionally solidified and single crystal castings, alloys tailored to exploit these microstructures, complex internal cooling schemes, and coatings. Equiaxed and directionally solidified castings are employed in current land based power generation equipment. These castings do not possess the ability to meet the efficiency targets as outlined above. The production use of premium single crystal components with complex internal cooling schemes in the latest generation of alloys is necessary to meet the ATS goals. However, at present, the use of single crystal components with complex internal cooling schemes is restricted to industrial sized or aeroderivative engines, and prototype utility sized components.

  19. Maintenance system improvement in cast iron foundry

    Directory of Open Access Journals (Sweden)

    S. Kukla

    2011-07-01

    Full Text Available The work presents the issue of technical equipment management in an iron foundry basing on the assumptions of the TPM system (Total Productive Maintenance. Exploitation analysis of automatic casting lines has been carried out and their work’s influence on the whole production system’s functioning has been researched. Within maintenance system improvement, implementation of autonomic service and planned lines’ review have been proposed in order to minimize the time of breakdown stoppages. The SMED method was used to optimize changeover time, and the OEE (Overall Equipment Effectiveness was applied to evaluate the level of resources usage before and after implementing changes. Further, the influence of the maintenance strategy of casting devices’ efficiency on own costs of casting manufac- ture was estimated.

  20. Cast construction elements for heat treatment furnaces

    Directory of Open Access Journals (Sweden)

    B. Piekarski

    2011-07-01

    Full Text Available The study presents sketches and photos of the cast creep-resistant components used in various types of heat treatment furnaces. The shape of the elements results from the type of the operation carried out in the furnace, while dimensions are adjusted to the size of the furnace working chamber. The castings are mainly made from the high-alloyed, austenitic chromium-nickel or nickel-chromium steel, selecting the grade in accordance with the furnace operating conditions described by the rated temperature, the type and parameters of the applied operating atmosphere, and the charge weight. Typical examples in this family of construction elements are: crucibles, roller tracks, radiant tubes and guides. The majority of castings are produced in sand moulds.

  1. The World's Largest Steel Casting Poured Successfully

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ The world's largest steel casting -- the upper beam (or the top head) for free forging oil hydraulic press with a 18,000-ton force capacity, was poured successfully by CITIC Heavy Machinery Co., Ltd. (CITICHM) on May 22, 2008. This head piece is 11.95 meters long, 3.8 meters wide, 4.59 meters high and about 520 tons in gross weight. Pouring is the most important and critical step during its manufacturing process. The production of this huge casting requires about 830 tons of refined molten steel from 10 smelting furnaces and pouring with six ladles into the mold cavity at one time, which made it currently the world's largest steel casting poured and the most one-time molten steel organized.

  2. Cast Aluminum Alloy for High Temperature Applications

    Science.gov (United States)

    Lee, Jonathan A.

    2003-01-01

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

  3. A new casting defect healing technology

    Energy Technology Data Exchange (ETDEWEB)

    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

    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.

  4. Thin wall ductile and austempered iron castings

    Directory of Open Access Journals (Sweden)

    E. Fraś

    2010-07-01

    Full Text Available It has been shown that it is possible to produce thin wall castings made of ductile iron with wall thickness in the range of 1.2 to 2.9 mm(without chills, cold laps and misruns. Thin wall ductile iron castings can be lighter (380 g than their substitutes made of aluminium alloys (580g. The kinetics of austenitising transformation was studied in unalloyed ductile iron. The advance of transformations during austenitising was monitored by measurement the fraction of martensite and also by dilatometic studies. It has been shown that in thin wall ductile iron castings austenitising at 880 oC for 20 minutes is adequate to obtain the austenite matrix at the end of the first stage of austempering heat treatment cycle.

  5. Diffusion of C and Cr During Creation of Surface Layer on Cast Steel Casting

    Directory of Open Access Journals (Sweden)

    Szajnar J.

    2014-10-01

    Full Text Available In paper a method of improvement in utility properties of unalloyed cast steel casting in result of diffusion of C and Cr in process of creation of surface layer is presented. The aim of paper was determination of diffusion range of basic elements of alloyed surface layer. Moreover a quantitative analysis of carbides phase strengthens alloyed surface layer of casting was carried out. The results of studies shown that important factors of surface layer creation are maximal temperature Tmax on granular insert – cast steel boundary dependent of pouring temperature, granularity Zw of Fe-Cr-C alloy insert and thickness of casting wall gśo. On the basis of obtained results was affirmed that with increase of thickness of casting wall increases range of diffusion in solid state in Fe-Cr-C grains and in liquid state. Moreover the range of Tmax = 13001500oC favours creation of the proper alloyed surface layers on cast steel.

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

    Science.gov (United States)

    Meyer, Thomas N.; Viswanathan, Srinath

    2002-09-17

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

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

    Science.gov (United States)

    Chhabra, M.; Singh, R.

    2015-04-01

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

  8. Quality control of cast brake discs

    Directory of Open Access Journals (Sweden)

    M. Stawarz

    2008-04-01

    Full Text Available The largest industrial application so far have the gray cast irons which are characterized by low tensile and bending strength, while at the same time they have good ultimate comprehensive strength. Additionally, the fatigue strength of gray cast irons is comparatively low and they are only to some extend sensitive for the surface waters effects. Cast iron is the material, which is comparatively easy to be processed, and for this reason – it is not expensive. Brake discs are exploited in particularly hard conditions. They must be resistant both against the thermal fatigue and abrasion wearing (at dry friction as well as against seizing, corrosion and mechanical load [1-3]. The gray cast iron, better than other materials, fulfills all the requirements necessary for making the material for the casts resistant against such tough conditions. This work reflects the researches aiming to define the quality of cast brake discs (ventilated and non-ventilated ones upon a period of their exploitation in real conditions. The following researches were performed: evaluations of the disc surface condition, measurement of disc thickness, examination of run – out flank and metallographic analysis. In order to more detailed recognition of mechanisms and reasons of brake discs wearing in real conditions, one should conduct additional examinations: computer analysis of the microstructure, chemical composition analysis, etc., as well as study of the technology of their production in foundries, where they are manufactured [4]. By obtaining the full set of the mentioned above data one can draw final conclusions and remove causes of possible defects.

  9. Modeling of casting microstructures and defects

    Energy Technology Data Exchange (ETDEWEB)

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

    1997-09-26

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

  10. Fundamentals of Numerical Modelling of Casting Processes

    DEFF Research Database (Denmark)

    Pryds, Nini; Thorborg, Jesper; Lipinski, Marek;

    Fundamentals of Numerical Modelling of Casting Processes comprises a thorough presentation of the basic phenomena that need to be addressed in numerical simulation of casting processes. The main philosophy of the book is to present the topics in view of their physical meaning, whenever possible......, rather than relying strictly on mathematical formalism. The book, aimed both at the researcher and the practicing engineer, as well as the student, is naturally divided into four parts. Part I (Chapters 1-3) introduces the fundamentals of modelling in a 1-dimensional framework. Part II (Chapter 4...

  11. Casting defects analysis by the Pareto method

    Directory of Open Access Journals (Sweden)

    B. Borowiecki

    2011-07-01

    Full Text Available On the basis of receive results formed of diagram Pareto Lorenz. On the basis of receive graph it affirmed, that for 70% general number casting defects answered 3 defects (9 contribution – 100% defects. For 70% general number defects of influence it has three type of causes: sand holes, porosity and slaginclusions. Thedefects show that it is necessary to take up construction gatingsystem. The remaining 8 causes have been concerned only 25%, with general number of casting defects. Analysis of receive results permit to determine of direction of correct actions in order to eliminate or to limit the most defects.

  12. Theoretical Model of Steel Continuous Casting Technology

    Institute of Scientific and Technical Information of China (English)

    C Gheorghies; I Crudu; C Teletin; C Spanu

    2009-01-01

    A theoretical model adapted for studying steel continuous casting technology was proposed.The model based on system theory contained input/output,command,and control parameters.The process was divided into five stages,i.e.,tundish,mold,guiding system,guiding-drawing system,and guiding-drawing-soft reduction system.The model can be used to describe the physicoehemical processes,thermal processes,chemical processes,and characteristics of the cast material according to the above-mentioned stages.It can also be applied to other metallurgical technologies and even to other industries (chemistry,food,etc.).

  13. Thin wall ductile and austempered iron castings

    OpenAIRE

    E. Fraś; M. Górny

    2010-01-01

    It has been shown that it is possible to produce thin wall castings made of ductile iron with wall thickness in the range of 1.2 to 2.9 mm(without chills, cold laps and misruns). Thin wall ductile iron castings can be lighter (380 g) than their substitutes made of aluminium alloys (580g). The kinetics of austenitising transformation was studied in unalloyed ductile iron. The advance of transformations during austenitising was monitored by measurement the fraction of martensite and also by dil...

  14. Combining the casting and punching technology

    Directory of Open Access Journals (Sweden)

    Zh. Ashkeyev

    2016-07-01

    Full Text Available In the article there are presented the results of studying the microstructure of metals obtained by the method of casting and punching in equal-channel step matrixes (ECSM. The analysis of the microstructure of metals obtained on the scanning and transmission microscope showed that owing to realization of intensive shift deformations on the inclined portion of ECSM there emerge shear bands which extend practically in parallel to zones of the matrix channels connection and influence positively closing and sealing all internal defects of cast blanks.

  15. Lymphoplasmacytic lymphoma causing light chain cast nephropathy.

    Science.gov (United States)

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

    2012-01-01

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

  16. An Integrated Die Casting Design System

    Institute of Scientific and Technical Information of China (English)

    Y; K; Woon; K; S; Lee

    2002-01-01

    Die casting process is one of the prime options for m anufacturing precisely dimensioned, sharply defined metal parts. The design of d ie casting dies comprises several stages and entails a large amount of time. Tra ditionally, the different stages of the die design were not integrated but exist as separate entities. Moreover, recurring modifications or even redesigns are r equired due to the complexity in achieving an accurate initial die design. As a result, die design is usually time-consuming and cos...

  17. Opportunities and challenges of Chinese die-casting market

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    The present status and perspectives of Chinese die-casting market were commented. In 2003, the total output of die castings in the whole country was 708 000 tons, in which the outputs of Al-alloy, Zn-alloy, Mg-alloy, Cu-alloy die castings were 474 600 tons, 222 000 tons, 5 800 tons, 5 600 tons, respectively, each accounted for 67%, 31.35%, 0.85%,0.8% of the total. The annual sale volume of die-casting machines was approximately 1 800. And the gross output value of dies approached RMB 38 billion, in which die-casting dies accounted for about 10%. In the die-casting industry of the entire country, the foreign capital enterprises, public-run enterprises, township and village enterprises, private enterprises accounted for over 80% of the total die-casting enterprises. Super huge die-casting groups are forming.

  18. Plans and Measures for Avoiding Casting-Air-Pollution

    Institute of Scientific and Technical Information of China (English)

    ZHOU Jian

    2003-01-01

    This article presents plans of preventing casting-air-pollution in practice, and some avoiding methods in detail. In modern times, environment protection is looked high upon day by day; green-casting thus becomes more and more important.

  19. Prediction of porosity in cast equiaxed alloy 718

    Energy Technology Data Exchange (ETDEWEB)

    Ko, Y.K. [Univ. of Alabama, Tuscaloosa, AL (United States); Sahai, V.; Overfelt, R.A. [Auburn Univ., AL (United States); Berry, J.T. [Mississippi State Univ., MS (United States)

    1995-12-31

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

  20. Manufacturing of thin walled near net shape iron castings

    DEFF Research Database (Denmark)

    Larsen, Per Leif

    2003-01-01

    The demand for near net shape thin walled iron castings is growing. This has several reasons, the main one is the need for lowering the fuel consumption of cars; the easiest way to do that is to lower the weight of the cars. The best way to do this was for a period of time believed...... to be substituting iron casings with aluminum castings. Substituting iron castings with aluminum castings is not as easy as first believed, and hence the substitution is very slow. This combined with the lack of fully exploiting the potential in iron castings, makes research in iron castings interesting. The 60.......000.000 cars produced world wide each year consumes enormous amounts of cast parts ! The aim of the project is to develop the green sand molding method on DISAMATIC to be able to deal with the new demands for thin walled near net shape castings in iron....

  1. Microstructure formation and properties of abrasion resistant cast steel

    OpenAIRE

    S. Parzych; Krawczyk, J.

    2010-01-01

    The so-called adamitic cast steels are characterised by a high abrasion resistance. These cast steels are of a pearlitic matrix with uniformly distributed hypereutectoid cementite precipitates. Apart from hypereutectoid cementite very often transformed ledeburite also occurs in the microstructure of these cast steels. Such cast steels contain chromium (app. 1 %) and nickel (app. 0.5 %) as alloy additions and sometimes their silicon content is increased. The presence of molybdenum is also perm...

  2. Optimizing hardenability of high chromium white cast iron

    Institute of Scientific and Technical Information of China (English)

    SU Ying-long; LI Dan; ZHANG Xue-kun

    2006-01-01

    The formulas proposed by J. Dodd and J. L. Parks for calculating the hardenability of high-Cr white cast iron under continuous cooling condition was recommended. For broader application, some supplements were made to the formula. Through tests on the half-cooling time of typical castings, the compositions of ideal alloys were precisely designed using the Dodd's formula. Hardness testing of heat-treated castings showed that the designed compositions were correct. The application of castings demonstrated excellent abrasion resistance.

  3. A silicon sheet casting experiment. [for solar cell water production

    Science.gov (United States)

    Bickler, D. B.; Sanchez, L. E.; Sampson, W. J.

    1980-01-01

    The casting of silicon blanks for solar cells directly without slicing is an exciting concept. An experiment was performed to investigate the feasibility of developing a machine that casts wafers directly. A Czochralski furnace was modified to accept a graphite ingot-simulating fixture. Silicon was melted in the middle of the ingot simulator in a boron nitride mold. Sample castings showed reasonable crystal size. Solar cells were made from the cast blanks. The performance is reported.

  4. Advances on Microstructure Modeling of Solidification Process of Shape Casting

    Institute of Scientific and Technical Information of China (English)

    柳百成; 许庆彦

    2004-01-01

    Simulation technology for shape casting at macro-scale has been successfully put into engineering application in a number of casting plants and as a result the quality of castings is assured, the research and development time is shortened, and the manufacturing cost is greatly saved as well. In this paper, modeling and simulation technologies of solidification process of shape casting at microstructure-scale, especially deterministic, cellular automaton, and phase field models are studied and reviewed.

  5. Is caste destiny? Occupational diversification among Dalits in rural India

    OpenAIRE

    Gang, Ira N.; Sen, Kunal; Yun, Myeong-Su

    2012-01-01

    The caste system - a system of elaborately stratified social hierarchy - distinguishes India from most other societies. Among the most distinctive factors of the caste system is the close link between castes and occupations, especially in rural India, with Dalits or Scheduled Castes (SC) clustered in occupations that were the least well paid and most degrading in terms of manual labour. Along with the Scheduled Tribes (STs), the SCs have the highest incidence of poverty in India, with poverty...

  6. Report on results of current and future metal casting

    Energy Technology Data Exchange (ETDEWEB)

    Unal, Cetin [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Carlson, Neil N. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-09-28

    New modeling capabilities needed to simulate the casting of metallic fuels are added to Truchas code. In this report we summarize improvements we made in FY2015 in three areas; (1) Analysis of new casting experiments conducted with BCS and EFL designs, (2) the simulation of INL’s U-Zr casting experiments with Flow3D computer program, (3) the implementation of surface tension model into Truchas for unstructured mesh required to run U-Zr casting.

  7. High speed twin roll casting of 6061 alloy strips

    OpenAIRE

    T. Haga; Sakaguchi, H.; H. Watari; S. Kumai

    2008-01-01

    Purpose: of this paper is to clear the possibility of high speed roll casting of thin strips of two aluminum alloys:6061 and recycled 6061. Mechanical properties of the roll cast 6061 and recycled 6061 strips were investigated inthe frame of this purpose.Design/methodology/approach: Methods used in the present study were high speed twin roll caster and lowtemperature casting. These methods were used to realize rapid solidification and increase the casting speed.Findings: are that 6061 and rec...

  8. THE WEAR RESISTANCE INCREASE OF CHROMIUM CAST IRON

    Directory of Open Access Journals (Sweden)

    V. M. Ilyushenko

    2016-01-01

    Full Text Available The article presents the results of the tests on the wear resistance of chromium cast irons of different compositions obtained in sand forms. It has been shown that increase of the wear resistance and mechanical properties of the cast iron is possible to obtain using the casting in metal molds. A further increase in wear resistance of parts produced in metal molds is possible by changing the technological parameters of casting and alloying by titanium.

  9. Clean Cast Steel Technology - Machinability and Technology Transfer

    Energy Technology Data Exchange (ETDEWEB)

    C. E. Bates; J. A. Griffin

    2000-05-01

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

  10. PRODUCTION OF CAST DIE INSERTS FOR HOT STRAINING

    Directory of Open Access Journals (Sweden)

    L. R. Dudetskaja

    2009-01-01

    Full Text Available The paper discusses distinctive design features of casting molds and technological aspects of producing cast inserts from 5ХНМЛ pressed steel. The designs of long-life metal shell molds are described. They ensure saving of molding material, increase of accepted material and improvement of quality of castings.

  11. Caste dominance and economic performance in rural India

    NARCIS (Netherlands)

    Kalwij, Adriaan; Iversen, Vegard; Verschoor, Arjan; Dubey, Amaresh

    2014-01-01

    Using household panel data for rural India covering 1993–94 and 2004–5, we test whether scheduled castes (SCs) and other minority groups perform better or worse in terms of income when resident in villages dominated by (i) upper castes or (ii) their own group. Theoretically, upper-caste dominance co

  12. 46 CFR 153.239 - Use of cast iron.

    Science.gov (United States)

    2010-10-01

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

  13. CASTING OF DETAILS OF WEAR-RESISTANT CHROME CAST IRONS FOR CHROMIC MILLS IN COMBINED MOLDS AND CHILLS

    Directory of Open Access Journals (Sweden)

    K. E. Baranovskij

    2009-01-01

    Full Text Available Relative wear resistance of chrome cast irons of eutectic composition is determined in laboratory and industry conditions. Complex alloyed eutectic cast iron with increased wear resistance and mechanical characteristics is developed.

  14. Casting directly from a computer model by using advanced simulation software FLOW-3D Cast ®

    Directory of Open Access Journals (Sweden)

    M. Sirviö

    2009-01-01

    Full Text Available ConiferRob - A patternless casting technique, originally conceived at VTT Technical Research Centre of Finland and furtherdeveloped at its spin-off company, Simtech Systems, offers up to 40% savings in product development costs, and up to two months shorterdevelopment times compared to conventional techniques. Savings of this order can be very valuable on today's highly competitivemarkets. Casting simulation is commonly used for designing of casting systems. However, most of the software are today old fashioned and predicting just shrinkage porosity. Flow Science, VTT and Simtech have developed new software called FLOW-3D Cast ® , whichcan simulate surface defects, air entrainment, filters, core gas problems and even a cavitation.

  15. Study on Compatibility between Converters and Casting Machines for Daily Steelmaking and Continuous Casting Scheduling

    Institute of Scientific and Technical Information of China (English)

    MA Feng-cai; ZHANG Qun

    2009-01-01

    In this paper, daily production scheduling is studied based on the Third Steelmaking Plant of Wuhan Iron and steel corporation (WISCO). To make sure the daily production plan is feasible, method of casting gToup is established, and the compatibility between two converters and three continuous casting devices in the Third Steelmaking Plant of WISCO is analyzed. The process flow chart of daily production scheduling is given in this paper. Then, algorithms and procedures for the simulation of daily production plan is developed. Using the actual data from the Third Steelmaking Plant, the feasible daily steelmaking plan and cast plan are given. The plan contains 7 groups of cast plan, figured out 54 converters, and a- bout 13,500 tons steel.

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

    Science.gov (United States)

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

    2011-09-01

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

  17. Structure and mechanical properties of vermicular cast iron in cylinder head casting

    Directory of Open Access Journals (Sweden)

    E. Guzik

    2009-01-01

    Full Text Available The paper discusses the problem of grain density and ferrite content in microstructure of vermicular graphite iron cast in bars of different section diameters and cylinder head casting. The experimental results regarding the section effect demonstrate that the nodule count, grain density and ferrite content are all function of the cast bar diameter in this particular case ranging from 0.6 to 8.0 cm and microstructure and mechanical properties in the cylinder head. The nodule count (or grain density has been reported to increase, while ferrite content was decreasing with decreasing casting diameter. The density number of the grains Nv has been related (by regression analysis to the undercooling degree

  18. Solidification of cast iron - A study on the effect of microalloy elements on cast iron

    DEFF Research Database (Denmark)

    Moumeni, Elham

    The present thesis deals with the heat transfer and solidification of ductile and microalloyed grey cast iron. Heterogeneous nucleation of nodular graphite at inclusions in ductile iron during eutectic solidification has been investigated. A series of ductile iron samples with two different...... of the austenite, in the last region to solidify. The superfine graphite which forms in this type of irons is short (10-20µm) and stubby. The microstructure of this kind of graphite flakes in titanium alloyed cast iron is studied using electron microscopy techniques. The methods to prepare samples of cast iron...... for comprehensive transmission electron microscopy of graphite and the surrounding iron matrix have been developed and explained. Dual beam microscopes are used for sample preparation. A TEM study has been carried out on graphite flakes in grey cast iron using selected area electron diffraction (SAED). Based...

  19. Cast Stainless Steel Ferrite and Grain Structure

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-09-01

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

  20. Fermilab joins in global live Web cast

    CERN Multimedia

    Polansek, Tom

    2005-01-01

    From 2 to 3:30 p.m., Lederman, who won the Nobel Prize for physics in 1988, will host his own wacky, science-centered talk show at Fermi National Accelerator Laboratory as part of a lvie, 12-hour, international Web cast celebrating Albert Einstein and the world Year of Physics (2/3 page)

  1. Carburizer Effect on Cast Iron Solidification

    Science.gov (United States)

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

    2014-06-01

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

  2. CAST reaches milestone but keeps on searching

    CERN Multimedia

    CERN Courier (september 2011 issue)

    2011-01-01

    After eight years of searching for the emission of a dark matter candidate particle, the axion, from the Sun, the CERN Axion Solar Telescope (CAST) has fulfilled its original physics programme.   Members of the CAST collaboration in July, together with dipole-based helioscope. CAST, the world’s most sensitive axion helioscope, points a recycled prototype LHC dipole magnet at the Sun at dawn and dusk, looking for the conversion of axions to X-rays. It incorporates four state-of-the-art X-ray detectors: three Micromegas detectors and a pn-CCD imaging camera attached to a focusing X-ray telescope that was recovered from the German space programme (see CERN Courier April 2010).  Over the years, CAST has operated with the magnet bores - the location of the axion conversion - in different conditions: first in vacuum, covering axion masses up to 20 meV/c2, and then with a buffer gas (4He and later 3He) at various densities, finally reaching the goal of 1.17 eV/c2 on 22 ...

  3. Costs Analysis of Iron Casts Manufacturing

    Directory of Open Access Journals (Sweden)

    S. Kukla

    2012-04-01

    Full Text Available The article presents the issues of costs analysis of iron casts manufacturing using automated foundry lines. Particular attention was paid to departmental costs, conversion costs and costs of in-plant transport. After the Pareto analysis had been carried out, it was possible to set the model area of the process and focus on improving activities related to finishing of a chosen group of casts. In order to eliminate losses, the activities realised in this domain were divided into activities with added value, activities with partially added value and activities without added value. To streamline the production flow, it was proposed to change the location of workstations related to grinding, control and machining of casts. Within the process of constant improvement of manufacturing processes, the aspect of work ergonomics at a workstation was taken into account. As a result of the undertaken actions, some activities without added value were eliminated, efficiency was increased and prime costs of manufacturing casts with regard to finishing treatment were lowered.

  4. The cern axion solar telescope (CAST)

    Energy Technology Data Exchange (ETDEWEB)

    Aalseth, C. E.; Arik, E.; Autiero, D.; Avignone, F. T.; Barth, K.; Bowyer, S. M.; Brauninger, H.; Brodzinski, R. L.; Carmona, J. M.; Cebrian, S.; Celebi, G.; Cetin, S.; Collar, J. I.; Creswick, R.; Delbart, A.; Delattre, M.; DiLella, L.; De Oliveira, R.; Eleftheriadis, Ch.; Erdutan, N.; Fanourakis, G.; Farach, H. A.; Fiorini, C.; Geralis, Th.; Giomataris, I.; Girard, T. A.; Gninenko, S. N.; Golubev, N. A.; Hasinoff, M.; Hoffmann, D.; Irastorza, I. G.; Jacoby, J.; Jeanneau, F.; Knopf, M. A.; Kovzelev, A. V.; Kotthaus, R.; Krčmar, M.; Krečak, Z.; Lakić, B.; Liolios, A.; Ljubičić, A.; Lutz, G.; Longoni, A.; Luzon, G.; Mailov, A.; Matveev, V. A.; Miley, H. S.; Morales, A.; Morales, J.; Mutterer, M.; Nikolaidis, A.; Nussinov, S.; Ortiz, A.; Pitts, W. K.; Placci, A.; Postoev, V. E.; Raffelt, G. G.; Riege, H.; Sampieto, M.; Sarsa, M.; Savvidis, I.; Stipčević, M.; Thomas, C. W.; Thompson, R. C.; Valco, P.; Villar, J. A.; Villierme, B.; Walckiers, L.; Wilcox, W.; Zachariadou, K.; Zioutas, K.

    2002-07-01

    A decommissioned LHC test magnet is being prepared as the CERN Axion Solar Telescope (CAST) experiment. The magnet has a field of 9.6 Tesla and length of 10 meters. It is being mounted on a platform to track the sun over plus or minus 8 to the sixth power vertically and plus or minus 45 to the sixth power, horizontally.

  5. The CAST X-ray telescope

    Energy Technology Data Exchange (ETDEWEB)

    Rosu, Madalin M. [Institut fuer Kernphysik, Technische Universitaet Darmstadt (Germany)

    2010-07-01

    CAST (CERN Axion Solar Telescope) is a project at the European Organization for Nuclear Research CERN in Geneva, which searches for Axions coming from the Sun. The most sensitive detector system used at CAST is the X-ray Wolter type I telescope. Its two constituents, the X-ray mirror optics and the fully depleted EPIC pn-CCD detector, were originally built for ABRIXAS and XMM-Newton space missions. Their combined use provides the X-ray telescope with the highest axion discovery potential of all CAST detectors, excellent imaging capability and almost 100% data tacking reliability in conditions of low background which is suppressed by a factor of 155 by focusing the photons from the aperture of the magnet of 14.5 cm{sup 2} to a spot of roughly 9.3 mm{sup 2} on the CCD chip. For achieving a high sensitivity the CCD chip is operated at -130 C in a vacuum vessel made of aluminum and a passive shield of copper and led to reduce the external {gamma}-ray. All these combined with a extremely thin and homogeneous entrance window of 20 nm located on the back side of the chip result in a quantum efficiency of >95% in the photon energy range of 1 to 7 keV, which is the interesting region for the axion search with the CAST experiment.

  6. Centrifugal Casting of Tubular Perovskite Membranes

    NARCIS (Netherlands)

    Mertins, Frederic H.B.; Kruidhof, Henk; Bouwmeester, Henny J.M.

    2005-01-01

    Dense tubular membranes were produced by centrifugal casting of an aqueous suspension, containing powder particles of the mixed-conducting perovskite La0.5Sr0.5CoO3−δ and a dispersant. The resulting green bodies were dried and sintered to produce tubes with a maximum length of 12 cm, having a relat

  7. New progresses of Chinese art casting

    Institute of Scientific and Technical Information of China (English)

    TAN De-rui

    2007-01-01

    @@ The Chinese art casting with 5 000 years history has been rapidly developed in recent ten years. This benefits from the great development of Chinese economy, the large-scale urban construction and transformation, the increasing demands for the cultural work of art, the loose religious environment and the expanding international market.

  8. Graphite formation in cast iron, phase 2

    Science.gov (United States)

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

    1985-01-01

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

  9. Cast Iron With High Carbon Content

    Science.gov (United States)

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

    1986-01-01

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

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

    OpenAIRE

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

    2014-01-01

    In casting steels for offshore construction, manufacturing integral casted structures to prevent fatigue cracks in the stress raisers is superior to using welded structures. Here, mold design and casting analysis were conducted for integral casting steel. The laminar flow of molten metal was analyzed and distributions of hot spots and porosities were studied. A prototype was subsequently produced, and air vents were designed to improve the surface defects caused by the release of gas. A radio...

  11. A new freeze casting technique for ceramics

    Science.gov (United States)

    Araki, Kiyoshi

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

  12. Cast Iron And Mineral Cast Applied For Machine Tool Bed - Dynamic Behavior Analysis

    OpenAIRE

    2015-01-01

    Cast iron and mineral cast are the materials most often used in the machine structural elements design (bodies, housings, machine tools beds etc.). The materials significantly differ in physical and mechanical properties. The ability to suppress vibration is one of the most important factors determining the dynamic properties of the machine and has a significant impact on the machining capabilities of a machine tool. Recent research and development trends show that there is a clear tendency t...

  13. The influence of solidification speed during heating on allotropic transformations of chromium cast iron casting

    Directory of Open Access Journals (Sweden)

    M. Przybył

    2008-08-01

    Full Text Available The unique stand to founding dilatometric samples ("on ready” which solidify with different cooling speeds was presented. The dilatometric investigations, X-ray, metallographic they disclosed the occurrence in matrix of chromium cast iron of considerable quantity of austenite in dependence from concentration of chromium (18% and 23% and the speed of solidification. Castings these despite large part of austenite mark with high hardness in raw state.

  14. The Configurable Aperture Space Telescope (CAST)

    Science.gov (United States)

    Ennico, Kimberly; Bendek, Eduardo A.; Lynch, Dana H.; Vassigh, Kenny K.; Young, Zion

    2016-07-01

    The Configurable Aperture Space Telescope, CAST, is a concept that provides access to a UV/visible-infrared wavelength sub-arcsecond imaging platform from space, something that will be in high demand after the retirement of the astronomy workhorse, the 2.4 meter diameter Hubble Space Telescope. CAST allows building large aperture telescopes based on small, compatible and low-cost segments mounted on autonomous cube-sized satellites. The concept merges existing technology (segmented telescope architecture) with emerging technology (smartly interconnected modular spacecraft, active optics, deployable structures). Requiring identical mirror segments, CAST's optical design is a spherical primary and secondary mirror telescope with modular multi-mirror correctors placed at the system focal plane. The design enables wide fields of view, up to as much as three degrees, while maintaining aperture growth and image performance requirements. We present a point design for the CAST concept based on a 0.6 meter diameter (3 x 3 segments) growing to a 2.6 meter diameter (13 x 13 segments) primary, with a fixed Rp=13,000 and Rs=8,750 mm curvature, f/22.4 and f/5.6, respectively. Its diffraction limited design uses a two arcminute field of view corrector with a 7.4 arcsec/mm platescale, and can support a range of platescales as fine as 0.01 arcsec/mm. Our paper summarizes CAST, presents a strawman optical design and requirements for the underlying modular spacecraft, highlights design flexibilities, and illustrates applications enabled by this new method in building space observatories.

  15. Aluminium Foam and Magnesium Compound Casting Produced by High-Pressure Die Casting

    Directory of Open Access Journals (Sweden)

    Iban Vicario

    2016-01-01

    Full Text Available Nowadays, fuel consumption and carbon dioxide emissions are two of the main focal points in vehicle design, promoting the reduction in the weight of vehicles by using lighter materials. The aim of the work is to evaluate the influence of different aluminium foams and injection parameters in order to obtain compound castings with a compromise between the obtained properties and weight by high-pressure die cast (HPDC using aluminium foams as cores into a magnesium cast part. To evaluate the influence of the different aluminium foams and injection parameters on the final casting products quality, the type and density of the aluminium foam, metal temperature, plunger speed, and multiplication pressure have been varied within a range of suitable values. The obtained compound HPDC castings have been studied by performing visual and RX inspections, obtaining sound composite castings with aluminium foam cores. The presence of an external continuous layer on the foam surface and the correct placement of the foam to support injection conditions permit obtaining good quality parts. A HPDC processed magnesium-aluminium foam composite has been developed for a bicycle application obtaining a suitable combination of mechanical properties and, especially, a reduced weight in the demonstration part.

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

    Science.gov (United States)

    Wróbel, Tomasz

    2014-05-01

    The paper presents the technology of bimetallic castings based on the founding method of layer coating directly in the cast process of the so-called method of mold cavity preparation. The prepared castings consist of two fundamental parts, i.e., the base and the working surface layer. The base part of the bimetallic casting is typical foundry material, i.e., unalloyed cast steel, whereas the working layer is a plate of austenitic alloy steel sort X2CrNi 18-9. The quality of the joint between the base part and the working layer was evaluated on the basis of ultrasonic non-destructive testing and structure examinations containing metallographic macro- and microscopic studies with the use of a light microscope (LOM) with microhardness measurements and a scanning electron microscope (SEM) with microanalysis of the chemical composition (energy dispersive 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.

  17. Establishment of mathematical moment model in twin casting rolling rolls

    Institute of Scientific and Technical Information of China (English)

    孙斌煜; 苑世剑; 张洪; 杜艳平; 张芳萍

    2002-01-01

    In continuous casting rolling process, the deformed body is different from the hot rolling strip. The metal in casting rolling zone is first assumed to be viscous fluid and the mathematical model of casting rolling force is established, then the calculating formula for casting rolling torque is derived. In addition, considering the effects of deforming cone and appendant torque of rotary junctions sealing ring, the calculating model which accords with casting rolling condition is found out. Theoretical formula is proved by experiment.

  18. Recent development of ductile cast iron production technology in China

    Institute of Scientific and Technical Information of China (English)

    Cai Qizhou; Wei Bokang

    2008-01-01

    Recent progress in the production and technology of ductile cast iron castings in China is reviewed.The manufacture and process control of as-cast ductile iron are discussed.The microstructure.properties and application of partial austenitization normalizing ductile iron and austempered duclile iron(ADI)are briefly depicted.The new development of duclile iron production techniques,such as cored-wire injection(wire-feeding nodularization)process,tundish cover ladle nodularizing process,horizontal continuous casting,and EPC process (lost foam)for ductile iron castings,etc.,are summarized.

  19. Recent development of ductile cast iron production technology in China

    Directory of Open Access Journals (Sweden)

    Cai Qizhou

    2008-05-01

    Full Text Available Recent progress in the production and technology of ductile cast iron castings in China is reviewed. The manufacture and process control of as-cast ductile iron are discussed. The microstructure, properties and application of partial austenitization normalizing ductile iron and austempered ductile iron (ADI are briefl y depicted. The new development of ductile iron production techniques, such as cored-wire injection (wire-feeding nodularization process, tundish cover ladle nodularizing process, horizontal continuous casting, and EPC process (lost foam for ductile iron castings, etc., are summarized.

  20. Preferential dissolution behaviour in Ni–Cr dental cast alloy

    Indian Academy of Sciences (India)

    Viswanathan S Saji; Han Cheol Choe

    2010-08-01

    A Ni–Cr–Mo dental alloy was fabricated by three different casting methods, viz. centrifugal casting, high frequency induction casting and vacuum pressure casting. The dependence of cast microstructure on the electrochemical corrosion behaviour was investigated using potentiodynamic cyclic and potentiostatic polarization techniques, impedance spectroscopy and scanning electron microscopy. The experimental results were compared and discussed with those obtained for a Co–Cr–Mo counterpart. The results of the study showed that the variation in casting morphologies with casting methods has only marginal influence in the overall corrosion resistance of Ni–Cr and Co–Cr dental alloys. There was severe preferential dissolution of Ni rich, Cr and Mo depleted zones from the Ni–Cr–Mo alloy. The overall corrosion resistance property of the Co–Cr base alloy was better than that of the Ni–Cr base alloy.

  1. Metallic Fuel Casting Development and Parameter Optimization Simulations

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-03-01

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

  2. Formation of microstructures in the spheroidal graphite cast iron

    Science.gov (United States)

    Wang, S.; Daloz, D.; Bruneseaux, F.; Lesoult, G.

    2012-01-01

    Pipeline systems for hydraulic networks are obtained via centrifugal casting of spheroidal graphite cast iron. The very high cooling rate that is achieved in the skin of the product can sometimes lead to carbide instead of graphite in cast iron. An experimental device has been built in the laboratory that allows reproducing the extreme thermal conditions encountered during formation of skin of centrifugally cast pipes. Liquid metal droplets fall on a cold substrate. Rapid directional solidification occurs. The temperature evolution of the lower surface of the droplet is recorded during the very first moment of the solidification (t cast state and the heat-treated state. They are compared to the centrifugally cast ones. A model of directional solidification of cast iron under a very large temperature gradient has been built. It allows explaining the transition from stable to metastable micro structure that was observed in the products and reproduced in the laboratory samples.

  3. Undercooling and nodule count in thin walled ductile iron castings

    DEFF Research Database (Denmark)

    Pedersen, Karl Martin; Tiedje, Niels Skat

    2007-01-01

    Casting experiments have been performed with eutectic and hypereutectic castings with plate thick¬nesses from 2 to 8 mm involving both temperature measurements during solidification and micro¬structural examination afterwards. The nodule count was the same for the eutectic and hypereutectic...... castings in the thin plates ( 4.3 mm) while in the 8 mm plate the nodule count was higher in the hypereutectic than in the eutectic castings. The minimum temperature prior to the eutectic recalescence (Tmin) was 15 to 20C lower for the eutectic than the hypereutectic castings. This is due to nucleation...... of graphite nodules which begins at a lover temperature in the eutectic than in the hypereutectic castings The recalescence (Trec) was however also larger for the eutectic casting and in the thin plates the maximum temperature after recalescence (Tmax) was the same in the eutectic and hypereutectic plates...

  4. Undercooling and nodule count in thin walled ductile iron castings

    DEFF Research Database (Denmark)

    Pedersen, Karl Martin; Tiedje, Niels Skat

    2007-01-01

    Casting experiments have been performed with eutectic and hypereutectic castings with plate thicknesses from 2 to 8 mm involving both temperature measurements during solidification and microstructural examination afterwards. The nodule count was the same for the eutectic and hypereutectic castings...... in the thin plates (≤4.3 mm) while in the 8 mm plate the nodule count was higher in the hypereutectic than in the eutectic castings. The minimum temperature before the eutectic recalescence (Tmin) was 15 to 20ºC lower for the eutectic than for the hypereutectic castings. This is due to nucleation of graphite...... nodules which begins at a lower temperature in the eutectic than in the hypereutectic castings. The recalescence ∆Trec was however also larger for the eutectic casting and in the thin plates the maximum temperature after recalescence (Tmax) was the same in the eutectic and hypereutectic plates...

  5. Fatigue life of ablation-cast 6061-T6 components

    Energy Technology Data Exchange (ETDEWEB)

    Tiryakioglu, Murat, E-mail: m.tiryakioglu@unf.edu [School of Engineering. University of North Florida, Jacksonville, FL 32224 (United States); Eason, Paul D. [School of Engineering. University of North Florida, Jacksonville, FL 32224 (United States); Campbell, John [Department of Metallurgy and Materials, University of Birmingham, Edgbaston B15 2TT (United Kingdom)

    2013-01-01

    The fatigue life of 6061-T6 alloy, normally used in its wrought form, was investigated in this study in cast form from parts produced by the new ablation casting process. All specimens were excised from military castings. Unidirectional tensile test results yielded elongation values comparable to forgings and extrusions. A total of 39 fatigue specimens were tested by the rotating cantilever beam technique at five maximum stress levels. Moreover nine specimens excised from a forging were also tested for comparison. Results revealed that the fatigue life of ablation-cast 6061-T6 (i) follows a three-parameter Weibull distribution, and (ii) is comparable to data from the 6061 forging and is superior to conventionally cast Al-7% Si-Mg alloy castings published in the literature. Analysis of the fracture surfaces of ablation-cast 6061-T6 via scanning electron microscopy showed the existence of fracture surface facets and multiple cracks propagating in different directions.

  6. Genetic evidence on the origins of Indian caste populations.

    Science.gov (United States)

    Bamshad, M; Kivisild, T; Watkins, W S; Dixon, M E; Ricker, C E; Rao, B B; Naidu, J M; Prasad, B V; Reddy, P G; Rasanayagam, A; Papiha, S S; Villems, R; Redd, A J; Hammer, M F; Nguyen, S V; Carroll, M L; Batzer, M A; Jorde, L B

    2001-06-01

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

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

    DEFF Research Database (Denmark)

    Sonne, Mads Rostgaard; Frandsen, J. O.; Hattel, Jesper Henri

    2015-01-01

    In this work, simulations of pouring, solidification and cooling, and residual stress evolution of sand and chill cast wind turbine main shafts is performed. The models are made in the commercial software MAGMAsoft. As expected, the cooling rate of the sand casting is shown to be much lower than...... for the chill casting, resulting in a very course microstructure.From the simulations the nodule count is found to be 17 nodules per mm2 and 159 nodules permm2 for the sand and chill casting, respectively, in the critical region of the main bearing seat.This is verified from nodule counts performed on the real...... cast main shafts. Residual stressevaluations show an overall increase of the maximum principal stress field for the chill casting,which is expected. However, the stresses are found to be in compression on the surface of thechill cast main shaft, which is unforeseen....

  8. Phase Transformation in Cast Superaustenitic Stainless Steels

    Energy Technology Data Exchange (ETDEWEB)

    Lee Phillips, Nathaniel Steven [Iowa State Univ., Ames, IA (United States)

    2006-01-01

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

  9. Physics of Spin Casting Dilute Solutions

    CERN Document Server

    Karpitschka, Stefan; Riegler, Hans

    2012-01-01

    We analyze the spin casting of dilute (ideal) binary mixtures of non-volatile solutes in volatile solvents as a prototype for evaporation-controlled processes that are increasingly used to deposit specifically structured (sub)monolayers ("evaporation-induced self-assembly"). The first analytical description of the thinning of a volatile liquid film simultaneously subject to spinning and evaporation is presented. It shows, that the duration of a spin casting process is linked to the process parameters via power laws. A diffusion-advection model leads analytically to the equation governing the spatio-temporal evolution of the internal film composition. Its solution reveals that the solute concentration enrichment, its gradient, and its time evolution are related to the process parameters via power laws. The physics behind the power laws is uncovered and discussed. This reveales universal insights into the interplay between the control parameters and their impact on the spatiotemporal evolution of the film compo...

  10. Palatal Surface Area of Maxillary Plaster Casts

    DEFF Research Database (Denmark)

    Darvann, Tron Andre; Hermann, Nuno V.; Ersbøll, Bjarne Kjær;

    2007-01-01

    -dimensional measurements of selected linear distances, curve lengths, and (surface) areas were carried out on maxillary plaster casts from individuals with unilateral or bilateral cleft lip and palate. The relationship between two-dimensional and three-dimensional measurements was investigated using linear regression....... Results and Conclusions: Error sources in the measurement of three-dimensional palatal segment surface area from a two-dimensional photograph were identified as photographic distortion (2.7%), interobserver error (3.3%), variability in the orientation of the plaster cast (3.2%), and natural shape...... variation (4.6%). The total error of determining the cleft area/palate surface area ratio was 15%. In population studies, the effect of using two-dimensional measurements is a decrease of discriminating power. In well-calibrated setups, a two-dimensional measurement of the cleft area/palate surface area...

  11. Sharatchandra’s Caste and Gender Consciousness

    Directory of Open Access Journals (Sweden)

    Narasingha Sil

    2015-01-01

    Full Text Available Sharatchandra Chattopadhyay’s attitude to the prevalent caste system and social ethos, especially concerning sex, love, and marriage and chastity of married as well as widowed women, shows a marked ambivalence. On one hand, his work demonstrates his progressive and liberal ideas emanating from Western contact and impact on late colonial India, and on Bengal in particular. On the other hand, and by the same token, his attitude to love, marriage, and sex shows marked affinity with the Victorian morality emanating from the society of colonial India’s metropolitan masters. The upshot of this historical and social context is that Sharatchandra was basically a caste conscious Hindu Brahmin and a firm believer in the patriarchal ethos of his contemporary society, his reputation as a compassionate (daradī or maramī writer exposing the ills of his society notwithstanding.

  12. Numerical simulation of semisolid continuous casting process

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A general mathematical model and boundary condition applicable to momentum and heat transfer in the semisolid continuous casting(SCC) process was established. Using the model, the numerical simulation of the momentum and heat transfer of molten metal was carried out in the SCC system. The obtained results fit well with the measured ones. Moreover, using the numerical simulating software, the effect of various factors on breakout and breakage was explored. The obtained results show that heat flow density of copper mold and the withdrawal beginning time are two major influencing factors. The larger the heat flow density of copper mold, or the shorter the withdrawal beginning time, the more stable the semisolid continuous casting process.

  13. Gel cast foam diesel particulate filters

    Energy Technology Data Exchange (ETDEWEB)

    Binner, J.G.P.; Hughes, S. [IPTME, Loughborough Univ., Loughborough (United Kingdom); Sambrook, R.M. [Dytech Corp. Ltd., Dronfield (United Kingdom)

    2004-07-01

    A new manufacturing route for foam ceramics based on gel casting has been developed and is being commercialised. Gel casting employs an organic monomer that is polymerised to cause the in-situ gelation of a foamed aqueous ceramic slurry. The primary advantage is the inherent flexibility of the process; the foams can be near net shape manufactured in a variety of shapes and sizes and after production are simply dried and fired. In addition, the porosity and pore size distribution can be varied to suit the application and a wide range of ceramics can be foamed with densities ranging from 5-40% of theoretical. Applications are diverse and include the potential to be used as diesel particulate filters (DPF). The present work examines this and concludes that filtration efficiencies of {>=}90% are achievable without generating a significant backpressure for the engine. (orig.)

  14. Solidification control in continuous casting of steel

    Indian Academy of Sciences (India)

    S Mazumdar; S K Ray

    2001-02-01

    An integrated understanding of heat transfer during solidification, friction/lubrication at solid-liquid interface, high temperature properties of the solidifying shell etc. is necessary to control the continuous casting process. The present paper elaborates upon the knowledge developed in the areas of initial shell formation, mode of mould oscillation, and lubrication mechanism. The effect of these issues on the caster productivity and the quality of the product has been discussed. The influence of steel chemistry on solidification dynamics, particularly with respect to mode of solidification and its consequence on strength and ductility of the solidifying shell, has been dealt with in detail. The application of these basic principles for casting of stainless steel slabs and processing to obtain good quality products have been covered.

  15. Optimum design of cast iron finned radiator

    Institute of Scientific and Technical Information of China (English)

    赵立华; 张泓森; 董重成

    2003-01-01

    The height, thickness and spacing of fins have an impact on the thermal characteristics of a radiator.The calculation of heat output and metal thermal intensity for cast iron finned radiator are given by using heat transfer formula of vertical plate and parallel fins. Each factor having effect on the metal thermal intensity of a radiator is analyzed and the optimum structure parameters of a radiator are given in order to maximize metal thermal intensity.

  16. Superior Weapons Systems Through Castings (SWC)

    Science.gov (United States)

    2012-11-30

    the near elimination of delta ferrite both in the as-cast structure. The morphology of the delta ferrite after HIPing at low temperatures (1950°F...handout for inclusion in NFFS membership/industry mailings Promotion on NFFS website and within NFFS electronic newsletters Coordination with the Foundry... Morphological / Solidification N Deformation Figure 7-1 Possible routes for synthesizing aluminum base nano-composite materials. (A) Self

  17. Prediction of Casting Defects Using Simulation Techniques

    Directory of Open Access Journals (Sweden)

    Tania Rodriguez Moliner

    2010-05-01

    Full Text Available The aim of the present paper is to show the evident advantages of using simulation techniques in foundry technologies. The considerable save of time and economic resources that implies the use of this techniques has spread worldwide. As in Cuba the use is not extended to the foundries, we intend to demonstrate the possibilities of the use of simulation software for the development of casting technologies.

  18. Development and investigation of electroslag continuous casting

    Institute of Scientific and Technical Information of China (English)

    Ximin Zang; Zhouhua Jiang; Tieyi Pan

    2007-01-01

    The principle and technological design of electroslag continuous casting (ESCC), including bifilar mode, T-shaped mould,and metal level detecting system, are detailed. Remelting was carried out for 1Cr18Ni9Ti stainless steel with ESCC. The surface finish, chemical composition, macro- and microstructures, and inclusions of the remelted billets were characterized. ESCC reduces the cost and increases the productivity in comparison to traditional ESR, while achieves comparably excellent products.

  19. Fracture analysis of chilled cast iron camshaft

    OpenAIRE

    Li Ping; Li Fengjun; Cai Anke

    2009-01-01

    The fracture of a camshaft made of chilled cast iron, installed in a home-made Fukang car, happened only after running over a distance of 6,200 km. The fractured camshaft was received to conduct a series of failure analyses using visual inspection, SEM observation of fracture section, microstructure analysis, chemical composition analysis and hardness examination and so on, while those of CKD camshaft made by Citro雗 Company in France was also simultaneously analyzed to compare the difference ...

  20. Die casting process otimization using Taguchi method

    Directory of Open Access Journals (Sweden)

    Denilson Jose Viana

    2013-11-01

    Full Text Available The aluminum die casting process has developed significantly in recent decades, occupying a prominent place for producing innovative engineering components. Among quality problems of this process is porosity due to several factors, including the process parameters that are difficult to determine, and are commonly selected by trial and error approach. This paper sought to answer the question: How to determine the best set of parameters of the aluminum die casting process to minimize porosity in the parts produced? Aiming to improve die casting aluminum parts quality through reducing of porosity. The main contribution of this paper focuses on the application of Taguchi method using ordinal categorical data (porosity classes as a quality characteristic, by analyzing the weighted signal-to-noise ratio. The experimental results were analyzed from the average effect of factors and analysis of variance (ANOVA.  In conclusion parameters metal temperature and speed of the first and second injection phase were the most significant in reducing the porosity of the part studied. Also, the Taguchi method achieved the expected result, bringing significant reduction of porosity in the part studied by optimizing the process parameters.

  1. Fisher Matrix Preloaded -- Fisher4Cast

    CERN Document Server

    Bassett, Bruce A; Hlozek, Renée; Kotze, Jacques

    2009-01-01

    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 3-D and 4-D visualisations of the forecasting landscape and to investigate the effects of growth and curvature on future cosmological surveys. Early releases have been available at http://www.cosmology.org.za since May 2008 with 750 downloads in the first year. Version 2.0 is made public with this paper and includes a Quick Start guide and the code used to produce the figures in this paper, in the hope that it will be useful to the cosmology and wider scientific communitie...

  2. Die Soldering in Aluminium Die Casting

    Energy Technology Data Exchange (ETDEWEB)

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

    2000-03-15

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

  3. Squeeze Casting of Semiolid A356 Alloy

    Directory of Open Access Journals (Sweden)

    Xiang-Jie Yang

    2014-05-01

    Full Text Available The rheo-squeeze casting (rheo-SQC combining the rheocasting and the SQC was developed, in which semisolid slurry was produced by the low superheat pouring with a shearing field (LSPSF process. The three-dimensional morphology of the primary α-Al phase and the rest spacing of slurry prepared by LSPSF process have been reconstructed and visualized, and the microstructures of squeeze cast A356 alloy have been obtained. Based on the three-dimensional microstructure reconstructed, their three-dimensional characterizations such as solid volume fraction and equivalent diameter of the extracted primary α-Al phase of the slurry were measured and calculated. And the microstructures of cross-section of squeeze cast product were investigated. Compared and analyzed the typical microstructure characteristics of parts in different positions produced by SQC and rheo-SQC, the results show that the primary α-Al phase was in the form of enriched dendrites across the whole section of parts produced by SQC. Nevertheless, in the relative case of the rheo-SQC, the whole formations of dendrites have been inhibited effectively, revealing a conspicuous modification in morphology and refinement of the primary α-Al phase. In addition, the solid fraction decreased from the centre to the verge of products along the slurry flow orientation.

  4. Successful magnet quench test for CAST.

    CERN Multimedia

    Brice Maximilien

    2002-01-01

    The CERN Axion Solar Telescope (CAST) consists of a prototype LHC dipole magnet with photon detectors at each end. It searches for very weakly interacting neutral particles called axions, which should originate in the core of the Sun. The telescope, located at Point 8, can move vertically within its wheeled platform, which travels horizontally along tracks in the floor. In this way, the telescope can view the Sun at sunrise through one end and at sunset through the other end. It has been cooled down to below 1.8 K and reached ~95% of its final magnetic field of 9 tesla before a quench was induced to test the whole cryogenic system under such conditions. The cryogenic system responded as expected to the magnet quench and CAST is now ready to start its three-year search for solar axions. Photos 01 & 02 : Members of the LHC cryogenics team pose in front of the axion telescope on the day of the first quench test, together with some of the CAST collaboration.

  5. Infant Perception of Incongruent Shapes in Cast Shadows

    Directory of Open Access Journals (Sweden)

    Kazuki Sato

    2015-04-01

    Full Text Available A cast shadow occurs when an object blocks the light from an illumination and projects a dark region onto a surface. Previous studies have reported that adults are slower to identify an object when the object has an incongruent cast shadow than when it has a congruent cast shadow (Castiello, 2001. Here, we used the familiarization-novelty preference procedure to examine whether 5- to 8-month-old infants could detect the relationship between object shapes and cast shadows. In Experiment 1, we examined the infants' ability to detect incongruency between objects and cast shadows. Results showed that 7- to 8-month olds could detect incongruence between the object shapes and the cast shadows, whereas 5- to 6-month olds did not. Yet, our control experiment showed that infants could not detect this incongruence from stimuli in which a white outline had been added to the original cast shadow to decrease the possibility of it being perceived as a cast shadow (Experiment 2. The results of these experiments demonstrate that 7- to 8-month olds responded to the congruence of cast shadows and to consistent contrast polarity between the cast shadow and its background.

  6. Physical Simulation of Investment Casting of Complex Shape Parts

    Science.gov (United States)

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

    2015-05-01

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

  7. Anisotropic shrinkage characteristics of tape cast alumina

    Science.gov (United States)

    Patwardhan, Jaideep Suresh

    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

  8. Electrochemical characterization of cast titanium alloys.

    Science.gov (United States)

    Cai, Zhuo; Shafer, Ty; Watanabe, Ikuya; Nunn, Martha E; Okabe, Toru

    2003-01-01

    A reaction layer forms on cast titanium alloy surfaces due to the reaction of the molten metal with the investment. This surface layer may affect the corrosion of the alloy in the oral environment. The objective of this study was to characterize the in vitro corrosion behavior of cast titanium alloys. ASTM Grade 2 CP titanium, Ti-6Al-4V, Ti-6Al-7Nb and Ti-13Nb-13Zr alloys were cast into a MgO-based investment. Experiments were performed on castings (N=4) with three surface conditions: (A) as-cast surface after sandblasting, (B) polished surface after removal of the reaction layer, and (C) sandblasted surface after removal of the reaction layer. Open-circuit potential (OCP) measurement, linear polarization, and potentiodynamic cathodic polarization were performed in aerated (air+10% CO(2)) modified Tani-Zucchi synthetic saliva at 37 degrees C. Potentiodynamic anodic polarization was subsequently conducted in the same medium deaerated with N(2)+10% CO(2) gas 2 h before and during the experiment. Polarization resistance (R(P)) and corrosion rate (I(CORR)) were calculated. Numerical results were subjected to nonparametric statistical analysis at alpha=0.05. The OCP stabilized for all the specimens after 6 x 10(4)s. Apparent differences in anodic polarization were observed among the different surfaces for all the metals. A passivation region followed by breakdown and repassivation were seen on specimens with surfaces A and C. An extensive passive region was observed on all the metals with surface B. The Kruskal-Wallis test showed no significant differences in OCP, R(p), I(CORR) or break down potential for each of the three surfaces among all the metals. The Mann-Whitney test showed significantly lower R(P) and higher I(CORR) values for surface C compared to the other surfaces. Results indicate that the surface condition has more effect on corrosion of these alloys than the surface reaction layer. Within the oxidation potential range of the oral cavity, all the metal

  9. Microstructures of electromagnetic casting and direct chill casting LY12 aluminum alloys

    Institute of Scientific and Technical Information of China (English)

    曹志强; 金俊泽; 郝海; 贾非

    2003-01-01

    LY12 aluminum alloys made by electromagnetic casting (EMC) and direct chill casting (DCC), were analyzed by optical microscope, differential scanning calorimetry, transmission electron microscope and X-ray diffraction. It is found that the surface and subsurface quality of the ingot is improved largely due to the absence of an ingot mold, which is impossible to achieve with conventional DCC. It is also found that the intense forced convection can promote the fast superheat evacuation and break the dendrite arms, leading to the grain multiplication and the appearance of a fine equiaxed grains over the whole cross section. As a result, the hardness of EMC specimens increases one time than that from DCC in the as-cast state. Even though after the solid solution treatment and the artificial aging, the DCC ingot still can not get the same hardness as EMC ones.

  10. Thin wall ductile iron casting as a substitute for aluminum alloy casting in automotive industry

    Directory of Open Access Journals (Sweden)

    M. Górny

    2009-01-01

    Full Text Available In paper it is presented thin wall ductile iron casting (TWDI as a substitute of aluminium alloy casting. Upper control arm made of ductile iron with wall thickness ranging from 2 – 3.7 mm was produced by inmold process. Structure, mechanical properties and computer simulations were investigated. Structural analysis of TWDI shows pearlitic-ferritic matrix free from chills and porosity. Mechanical testing disclose superior ultimate tensile strength (Rm, yield strength (Rp0,2 and slightly lower elongation (E of TWDI in comparison with forged control arm made of aluminium alloy (6061-T6. Moreover results of computer simulation of static loading for tested control arms are presented. Analysis show that the light-weight ductile iron casting can be loaded to similar working conditions as the forged Al alloy without any potential failures.

  11. The impact of breaks during foundry work of the pressure casting machine on casting quality

    Directory of Open Access Journals (Sweden)

    S. Borkowski

    2010-10-01

    Full Text Available The result in the appearance of the technical object damage are its failures, which are considered as the most important causes of productivity loss in the technical objects. The article introduces main types of losses resulting from the downtimes of a casting machine. The time impact analysis of the font mould failure and the remaining time of the machine's failures on the castings quality was conducted. The failure time structure of the font mould and other failures of the machine was presented.

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

    Directory of Open Access Journals (Sweden)

    Pokusová Marcela

    2014-12-01

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

  13. Characterization of Casting Defects in Typical Castings of a Directionally Solidified Superalloy

    Science.gov (United States)

    1979-08-01

    used to evaluate grain misorientation effects in D.S. MAR - M247 superalloy (17). Scatter of this nature has been observed previously in equiaxed cast...found associated with the fracture surfaces In the previous study on tje effect of off-axis grain growth on cylindrical cast bars of D.S. MAR - M247 , 1800...significant that no instances of failures associated with emergent grains were observed in the MAR - M247 study. In the present investigation of PWA 1422, no

  14. Examples of material solutions in bimetallic layered castings

    Directory of Open Access Journals (Sweden)

    S. Tenerowicz

    2011-07-01

    Full Text Available In paper is presented technology of bimetallic layered castings based on founding method of layer coating directly in cast process so-called method of mould cavity preparation. Prepared castings consist two fundamental parts i.e. bearing part and working part (layer. The bearing part of bimetallic layered casting is typical foundry material i.e. pearlitic grey cast iron, whereas working part (layer is depending on accepted variant plates of alloy steels sort X6Cr13, X12Cr13, X10CrNi18-8 and X2CrNiMoN22-5-3. The ratio of thickness between bearing and working part is 8:1. The verification of the bimetallic layered castings was evaluated on the basis of ultrasonic NDT (non-destructive testing, structure and macro- and microhardness researches.

  15. SIMULATION OF THE TWIN ROLL STAINLESS STRIP CASTING PROCESS

    Institute of Scientific and Technical Information of China (English)

    Y.C. Miao; X.M. Zhang; G.D. Wang; H.S. Di; X.H. Liu

    2001-01-01

    The position of the solidification completed temperature of twin roll stainless strip casting process is very important to the quality of the casting strip. In order to control this position, the solidification completed temperature should be known at first.The present paper first simulated dendritic microsegregation under conditions of twin roll stainless strip casting, and got the relationship between the temperature and solid fraction of the mush zone. The temperatures such as ZDT (equal to the solidification completed temperature) and LIT (liquid impenetrable temperature), et al., also were obtained. Then by using the turbulent model, the flow and thermal fields of the pool of the twin roll stainless strip casting, and the speed and temperature fields of different casting speeds were given and also explained. The results are coincident with the experimental result. Combined with the results of these two simulations. the appropriated casting speed was found.

  16. Properties shaping and repair of selected types of cast iron

    Directory of Open Access Journals (Sweden)

    J. Szajnar

    2007-04-01

    Full Text Available The paper presents research results of twofold use of TIG - Tungsten Inert Gas also known as GTA - Gas Tungsten Arc. First is surfacing by welding on cold and hot-cold to repair chromium cast iron with chromium content about 15%. Second is remelting with electric arc of selected gray (with pearlitic matrix and ductile (with ferritic-pearlitic matrix cast iron. Repair of cast iron elements was realized in order to cut out a casting defects. Defects decrease a usability of castings for constructional application and increase a manufacturing costs. Application of surface heat treatment guarantees mechanical properties i.e. hardness and wear resistance improvement. The result of investigations show possibility of castings repair by put on defects a good quality padding welds, which have comparable properties with base material. Use of electric arc surface heat treatment resulted in increase of hardness and wear resistance, which was measured on the basis of ASTM G 65 - 00 standard.

  17. Method and mold for casting thin metal objects

    Energy Technology Data Exchange (ETDEWEB)

    Pehrson, Brandon P; Moore, Alan F

    2014-04-29

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

  18. Status quo and development trend of lost foam casting technology

    Directory of Open Access Journals (Sweden)

    Fan Zitian

    2014-07-01

    Full Text Available Lost foam casting (LFC technology has been widely applied to cast iron and cast steel. However, the development of LFC for Al and Mg alloys was relatively slower than that for cast iron and cast steel. The application of LFC to Al and Mg alloys needs more effort, especially in China. In this paper, the development history of LFC is reviewed, and the application situations of LFC to Al and Mg alloys are mainly discussed. Meanwhile, the key problems of LFC for Al and Mg alloys are also pointed out. Finally, the prospects for LFC technology are discussed, and some special new LFC technologies are introduced for casting Al and Mg alloys. In future, the development trends of green LFC technology mainly focus on the special new LFC methods, metal material, coating, heat treatment, new foam materials as well as purification technology of tail gas, etc.

  19. Status quo and development trend of lost foam casting technology

    Institute of Scientific and Technical Information of China (English)

    Fan Zitian; Jiang Wenming; Liu Fuchu; Xiao Botao

    2014-01-01

    Lost foam casting (LFC) technology has been widely applied to cast iron and cast steel. However, the development of LFC for Al and Mg aloys was relatively slower than that for cast iron and cast steel. The application of LFC to Al and Mg aloys needs more effort, especially in China. In this paper, the development history of LFC is reviewed, and the application situations of LFC to Al and Mg aloys are mainly discussed. Meanwhile, the key problems of LFC for Al and Mg aloys are also pointed out. Finaly, the prospects for LFC technology are discussed, and some special new LFC technologies are introduced for casting Al and Mg alloys. In future, the development trends of green LFC technology mainly focus on the special new LFC methods, metal material, coating, heat treatment, new foam materials as wel as puriifcation technology of tail gas, etc.

  20. Development,Application and Problem of Ductile Iron Lost Foam Casting Technology in China

    Institute of Scientific and Technical Information of China (English)

    He Wenhao; Ye Shengping; Han Xiaohong; Tang Suoyun

    2010-01-01

    @@ Lost-foam casting is a 21st century green casting technology.Over the past decade,there has been an extraordinary development in lost-foam casting in China;and ductile iron lost-foam casting has developed even more rapidly in foundry equipment,foundry raw materials,and casting engineers.

  1. CHOICE OF MATERIAL AND MANUFACTURING TECHNOLOGY OF CASTING

    Directory of Open Access Journals (Sweden)

    L. I. Kupriyanova

    2016-01-01

    Full Text Available As a result of the carried out work abundant type of steel was chosen for casting production of asterisk of the excavator «Kamatsu». This type of steel is widely used as the wearproof steel working in the conditions of abrasive and shock – abrasive wear. Mathematical modeling of process of filling and hardening of casting was done and it confirmed a choice of the technology to produce casting without faulty parts.

  2. Mandated political representation and crimes against the low castes

    OpenAIRE

    Girard, Victoire

    2016-01-01

    Mandated political representation over the last twenty years has had a different impact on the reporting of crime by the low castes than what is observed for the reporting of crime by women. I exploit the timing of the implementation of mandated political representation of the low castes to examine its effect on crime reports by these people. Mandated political representation of the low castes in India appears to affect the declaration of crime only for two very specific crime categories: ide...

  3. The labor/land ratio and India's caste system

    OpenAIRE

    Duleep, Harriet

    2012-01-01

    This paper proposes that India's caste system and involuntary labor were joint responses by a nonworking landowning class to a low labor/land ratio in which the rules of the caste system supported the institution of involuntary labor. The hypothesis is tested in two ways: longitudinally, with data from ancient religious texts, and cross-sectionally, with twentieth-century statistics on regional population/land ratios linked to anthropological measures of caste-system rigidity. Both the longit...

  4. Recent development of ductile cast iron production technology in China

    OpenAIRE

    Cai Qizhou; Wei Bokang

    2008-01-01

    Recent progress in the production and technology of ductile cast iron castings in China is reviewed. The manufacture and process control of as-cast ductile iron are discussed. The microstructure, properties and application of partial austenitization normalizing ductile iron and austempered ductile iron (ADI) are briefl y depicted. The new development of ductile iron production techniques, such as cored-wire injection (wire-feeding nodularization) process, tundish cover ladle nodularizing proc...

  5. The history and present of art casting in China

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    @@ A compendiary review of art casting in China: History of art casting in china has been over 5000 years. In the past few thousand years, numerous forming and decorating skills of art castings had been created, and left behind precious treasures in the world metal arts and crafts. In individual historical period and at different terrain, a unique artistic style formed,which flashed brilliant light in world artistic treasury.

  6. Gradient porous hydroxyapatite ceramics fabricated by freeze casting method

    Science.gov (United States)

    Zuo, Kai-hui; zhang, Yuan; Jiang, Dongliang; Zeng, Yu-Ping

    2011-04-01

    By controlling the cooling rates and the composition of slurries, the gradient porous hydroxyapatite ceramics are fabricated by the freeze casting method. According to the different cooling rate, the pores of HAP ceramics fabricated by gradient freeze casting are divided into three parts: one is lamellar pores, another is column pore and the last one is fine round pores. The laminated freeze casting is in favour of obtaining the gradient porous ceramics composed of different materials and the ceramics have unclear interfaces.

  7. Dynamic control of crystallinity in polymer film casting process

    OpenAIRE

    Thananchai Leephakpreeda

    2005-01-01

    This paper presents an approach for dynamic control of crystallinity in polymer film casting process. As known, the transients of crystallization dictate the microstructures of semi-crystalline polymer during solidification. In turn, the properties of finished products can be determined by adjustable variables in polymer film casting process such as temperature of chill roll. In this work, an experimental model of the solidification in film casting process is derived by a system identificatio...

  8. A new approach to develop complicated superalloy castings

    Institute of Scientific and Technical Information of China (English)

    WU Jian-tao; FENG Di; LI Jun-tao; KONG Sheng-guo; PEI Zhong-ye

    2006-01-01

    An integrative computer aided investment casting (CAIC) technology for making complicated superalloy castings was described. Key processes of CAIC were discussed including the choice of SLS (Selectively Laser Sinterihg)materials, sintering parameters, solidification simulation and gating and risering system optimization. Using CAIC process,many large-sized quality superalloy castings with complicated shape and thin wall have been produced successfully and economically in Central Iron & steel Research Institute (CISRI).

  9. A new approach to develop complicated superalloy castings

    Directory of Open Access Journals (Sweden)

    WU Jian-tao

    2006-05-01

    Full Text Available An integrative computer aided investment casting (CAIC technology for making complicated superalloy castings was described. Key processes of CAIC were discussed including the choice of SLS (Selectively Laser Sintering materials, sintering parameters, solidification simulation and gating and risering system optimization. Using CAIC process, many large-sized quality superalloy castings with complicated shape and thin wall have been produced successfully and economically in Central Iron & steel Research Institute (CISRI.

  10. Solidification and microstructure of thin walled ductile cast iron

    DEFF Research Database (Denmark)

    Pedersen, Karl Martin

    2006-01-01

    In the recent years there has been an increasing interest in light constructions in order to save weight in e.g. cars. Ductile cast iron has good mechanical properties but it is necessary to re­duce the wall thicknesses of the castings in order to reduce the weight. Reducing the wall thicknesses...... of the casting will increase the cooling rates and by that change the conditions for nucleation and growth during solidification....

  11. Reengineering of Permanent Mould Casting with Lean Manufacturing Methods

    Directory of Open Access Journals (Sweden)

    R. Władysiak

    2007-07-01

    Full Text Available At the work were introduced main areas of production system project of casts produced in permanent moulds, that constitutes reengineering of conventional production system according to Lean Manufacturing (LM methods. New resolution of cooling of dies with water mist was shown to casting of car wheels made from aluminium alloys in low pressure casting process. It was implemented as a part of goal-oriented project in R.H. Alurad Sp.z o.o. in Gorzyce. Its using intensifies solidification and self-cooling of casts shortening the time of casting cycle by the 30%. It was described reorganizing casting stations into multi-machines cells production and the process of their fast tool’s exchange with applying the SMED method. A project of the system was described controlling the production of the foundry with the computer aided light Kanban system. A visualization of the process was shown the production of casts with use the value stream mapping method. They proved that applying casting new method in the technology and LM methods allowed to eliminate down-times, to reduce the level of stocks, to increase the productivity and the flow of the castings production.

  12. An heuristic based practical tool for casting process design

    Energy Technology Data Exchange (ETDEWEB)

    Nanda, N.K.; Smith, K.A.; Voller, V.R.; Haberle, K.F. [Univ. of Minnesota, Minneapolis, MN (United States). Dept. of Civil Engineering

    1995-12-31

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

  13. Investment casting or powder metallurgy – the ecological aspect

    Directory of Open Access Journals (Sweden)

    J. Tomasik

    2009-04-01

    Full Text Available The paper presents an analysis of manufacturing methods of material-saving products in relation to investment castings and sinteredpowder technology. Surface microgeometry, shape accuracy, performance parameters, manufacturing costs and energy consumption weretaken into account to make the optimal choice. The analysis was conducted by comparing test results for sintered powder products basedon Distaloy AB alloy that consists of 0.55% C, 1.5% Cu, 1.75% Ni and 0.5% Mo and investment castings made of high alloy cast steel andnodular cast iron. The analysis made it possible to choose the best technology, considering also the ecological aspect.

  14. Numerical Simulation System for Casting Process in Concurrent Engineering

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    According to the implementing principle and application background of the Concurrent Engineering (CE) project, studies on the integration of numerical simulation system for casting process with CE, simulation of turbulent phenomena in filling process of casting by Algebraic Stress Model (ASM), computation efficiency of filling process and quantitative prediction of shrinkage cavity and porosity under feeding condition of several risers are discussed. After the simulation of casting process of typical magnesium-based alloy casting with complicated structure, remarkable success in assuring the quality is also presented.

  15. Digital management technology and its application to investment casting enterprises

    Directory of Open Access Journals (Sweden)

    Xiao-yuan Ji

    2016-09-01

    Full Text Available With the advent of Industry 4.0, more and more investment casting enterprises are implementing production manufacturing systems, especially in the last two years. This paper summarizes three new common requirements of the digital management aspect in precision casting enterprises, and puts forward three corresponding techniques. They are: the production process tracking card technology based on the main-sub card mode; the workshop site production process processing technology based on the barcode; and the equipment data integration technology. Then, this paper discusses in detail the principle, application and effect of these technologies; to provide the reference for enterprises to move towards digital casting and intelligent casting.

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

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-05-01

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

  17. Caste ratios affect the reproductive output of social trematode colonies.

    Science.gov (United States)

    Kamiya, T; Poulin, R

    2013-03-01

    Intraspecific phenotypic diversification in social organisms often leads to formation of physical castes which are morphologically specialized for particular tasks within the colony. The optimal caste allocation theory argues that specialized morphological castes are efficient at specific tasks, and hence different caste ratios should affect the ergonomic efficiency, hence reproductive output of the colony. However, the reproductive output of different caste ratios has been documented in few species of insects with equivocal support for the theory. This study investigated whether the ratios of nonreproductive and reproductive morphs affect the reproductive output of a recently discovered social trematode, Philophthalmus sp., in which the nonreproductive members are hypothesized to be defensive specialists. A census of natural infections and a manipulative in vitro experiment demonstrated a positive association between the reproductive output of trematode colonies and the ratio of nonreproductive to reproductive morphs in the presence of an intra-host trematode competitor, Maritrema novaezealandensis. On the contrary, without the competitor, reproductive output was negatively associated with the proportion of nonreproductive castes in colonies. Our findings demonstrate for the first time a clear fitness benefit associated with the nonreproductive castes in the presence of a competitor while illustrating the cost of maintaining such morphs in noncompetitive situations. Although the proximate mechanisms controlling caste ratio remain unclear in this trematode system, this study supports the prediction that the fitness of colonies is influenced by the composition of specialized functional morphs in social organisms, suggesting a potential for adaptive shifts of caste ratios over evolutionary time.

  18. SYSTEMATIC AND DYNAMIC PROPER-TIES OF CASTING HOT SPOT

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The variation of casting hot spot with proceeding of solidification and components of casting-mold system is studied by the technique of numerical simulation of solidification.The result shows that the thickest part of casting is not exactly the last part of solidification in the casting, while the last part of solidification is not exactly casting hot spot at the early stage of solidification.The location, size, shape and number of casting hot spot change with geomitric, physical and technological factors of the casting-mold system such as thickness of the casting secondary wall and with the passage of time in the course of the solidification.The former is known as the systematic property of hot spot and the latter, dynamic property.Only when the properties of hot spot are grasped completely and accurately, can it be fed more effectively.By doing so, not only sound castings can be obtained, but also riser efficiency can be improved.

  19. PRINCIPALLY NEW EFFECTIVE CASTING PROCESS OF THE HOLLOW CYLINDRICAL SLUGS OF CAST IRON BY METHOD OF DIRECTIONAL SOLIDIFICATION

    Directory of Open Access Journals (Sweden)

    E. I. Marukovich

    2010-01-01

    Full Text Available The advantages of the new method of the hollow ingots production of cast iron are presented. The thermal state of crystallizer at cyclic temperature influences on its inside face, the ingot hardening and cast iron structure formation in conditions of intensive one-sided heat sink is examined. The comparative data on properties and exploitation characteristics of the parts, produced by different ways of casting is given.

  20. Influence of melt feeding scheme and casting parameters during direct-chill casting on microstructure of an AA7050 billet

    OpenAIRE

    Zhang, L; T. Subroto; Katgerman, L.; Eskin, DG; Miroux, A

    2012-01-01

    © The Minerals, Metals & Materials Society and ASM International 2012 Direct-chill (DC) casting billets of an AA7050 alloy produced with different melt feeding schemes and casting speeds were examined in order to reveal the effect of these factors on the evolution of microstructure. Experimental results show that grain size is strongly influenced by the casting speed. In addition, the distribution of grain sizes across the billet diameter is mostly determined by melt feeding scheme. Grains...

  1. Shrinkages in heavy-sized cast components of nodular cast iron – NDT and fatigue

    Directory of Open Access Journals (Sweden)

    Bleicher Christoph

    2014-06-01

    Full Text Available Material defects like shrinkages, dross, pores and chunky graphite are likely to occur in thick-walled castings and are a challenge for the foundries and their customers. These defects are mostly detected with handheld ultrasonic testing (UT or X-ray analysis. Within a research project done at the Fraunhofer Institute for Structural Durability and System Reliability LBF, the fatigue of Dross, shrinkages and chunky graphite in thick-walled cast material GGG-40 was estimated based on X-ray and fatigue tests on bending specimens. High fatigue reductions were received for the different material imperfections. Based on these impressions a further research project was executed at the Fraunhofer LBF to get an estimation of the informational value of UT in relation to fatigue of shrinkages in thick-walled castings of the material EN-GJS-400-18U-LT, EN-GJS-450-18 and EN-GJS-700-2. With the help of X-ray analysis and the UT technique Sampling Phased Array (SPA information about geometry and density were derived for a numerical analysis of shrinkages in thick-walled castings concerning fatigue. The following text summarizes the fatigue results achieved in the two research projects with the help of the X-ray and UT analysis.

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

    Science.gov (United States)

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

    2013-02-01

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

  3. Caste and Punishment : The Legacy of Caste Culture in Norm Enforcement

    OpenAIRE

    Hoff, Karla Ruth; Kshetramade, Mayuresh; Fehr, Ernst

    2009-01-01

    Well-functioning groups enforce social norms that restrain opportunism, but the social structure of a society may encourage or inhibit norm enforcement. This paper studies how the exogenous assignment to different positions in an extreme social hierarchy - the caste system - affects individuals' willingness to punish violations of a cooperation norm. Although the analysis controls for indi...

  4. Continuation of Crosscutting Technology Development at Cast

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Roe-Hoan

    2012-03-31

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

  5. Internal adaptation of cast titanium crowns

    Directory of Open Access Journals (Sweden)

    Sicknan Soares da Rocha

    2007-08-01

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

  6. CAST begins its search for solar axions.

    CERN Multimedia

    Maximilien Brice

    2002-01-01

    The CERN Axion Solar Telescope (CAST) consists of a prototype LHC dipole magnet with photon detectors at each end. It has started searching for very weakly interacting neutral particles called axions, which should originate in the core of the Sun. Photos 01 02: The telescope, located at Point 8, can move vertically within its wheeled yellow platform, which travels horizontally along tracks in the floor. In this way, the telescope can view the Sun at sunrise through one end (left) and at sunset through the other. Photos 03 04: Sunrise photon detectors at one end of the telescope.

  7. Phase Transformations in Cast Duplex Stainless Steels

    Energy Technology Data Exchange (ETDEWEB)

    Yoon-Jun Kim

    2004-12-19

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

  8. Materials on dies for pressure die casting

    Directory of Open Access Journals (Sweden)

    E. Ragan

    2012-01-01

    Full Text Available In the contribution the stress of die materials of thermal fatigue is defi ned and material life is derived theoretically and compared with the measured values. The important properties of the die materials as thermal conductivity, coeffi cient of thermal expansivity, modulus of elasticity and mechanical properties are described. Binding to it single die materials as carbon steels and chrome-tungsten steels are analyzed. As the perspective die material for pressure die casting of ferrous metals appears molybdenum with regard to advantageous properties.

  9. Web life: Planet SciCast

    Science.gov (United States)

    2009-08-01

    So what is the site about? Planet SciCast is an online repository for short films about science - a bit like a science-specific, moderated version of YouTube. As of July 2009, the site hosts over 150 films on topics ranging from CERN's Large Hadron Collider to fun things to do with treacle. New content appears on the site every few weeks, and some films include links to information about related experiments, demos and activities. The site also runs an annual competition aimed at getting more people involved in making science films, with prizes in categories like "best original score" and "best presenter".

  10. Phase Transformations in Cast Duplex Stainless Steels

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yoon-Jun [Iowa State Univ., Ames, IA (United States)

    2004-01-01

    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 σ and χ 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 (σ + χ) 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, σ was stabilized with increasing Cr addition and χ 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

  11. Sharing casting technological data on web site

    Institute of Scientific and Technical Information of China (English)

    Sun Xun; Li Hailan; Wang Junqing; Piao Dongxue; Hou Gang; Guan Yang; Wang Penghua; Zhu Qiang; Xle Huasheng

    2008-01-01

    Based on database and asp.net technologies, a web platform of scientific data in the casting technology field has been developed. This paper presents the relevant data system structure, the approaches to the data collection, the applying methods and policy in data sharing, and depicts the collected and shared data recently finished. Statistics showed that there are about 20,000 visitors in China every day visiting the related data through the web, proving that many engineers or other relevant persons are interested in the data.

  12. Optimization of squeeze casting parameters for non symmetrical AC2A aluminium alloy castings through Taguchi method

    Energy Technology Data Exchange (ETDEWEB)

    Senthil, P. [Coimbatore Institute of Engineering and Technology, Coimbatore (India); Amirthagadeswaran, K. S. [Government College of Technology, Coimbatore (India)

    2012-04-15

    This paper reports a research in which an attempt was made to prepare AC2A aluminium alloy castings of a non symmetrical component through squeeze casting process. The primary objective was to investigate the influence of process parameters on mechanical properties of the castings. Experiments were conducted based on orthogonal array suggested in Taguchi's offline quality control concept. The experimental results showed that squeeze pressure, die preheating temperature and compression holding time were the parameters making significant improvement in mechanical properties. The optimal squeeze casting condition was found and mathematical models were also developed for the process.

  13. Effect of casting speed and delay time on the residual stresses in centrifugal casting of aluminium rods

    Directory of Open Access Journals (Sweden)

    Adesoji A. OYEDEJI

    2016-07-01

    Full Text Available Longitudinal slitting technique has been employed to determine the residual stresses in centrifugal cast aluminium rods. Residual stresses were found to decrease with increase in casting speed in the centrifugal casting. The residual stresses of the aluminium rods cast at speeds of 100, 200, 300, 400 and 500rpm and at zero (0 second delay time have lower residual stresses as compared to those cast at the same varying casting speeds at ten (10 seconds delay time. At the different casting speeds, residual stress ratio (g was found to decrease with increase in the casting speeds with values of 40.91%, 31.82%, 22.73%, 13.64% and 9.09% at zero second delay time, while at ten seconds delay time the residual stress ratios were 68.18%, 59.09%, 54.55%, 50.00% and 36.36% respectively. Reduction in residual stress with increase in speed and delay time is attributed to the greater centrifugal forces created by the increasing casting speeds on the solidification of the molten aluminium.

  14. Simulation study on three casting processes for a marine propeller hub body

    Directory of Open Access Journals (Sweden)

    Wang Tongmin

    2013-11-01

    Full Text Available The mold filling and solidification process of a marine propeller hub were simulated using ProCAST? Three casting processes ?gravity casting, centrifugal casting and low pressure casting ?were compared in order to get the best process. The heat transfer coefficient of the casting/mold interface was determined using a reverse method. The simulated results of velocity, temperature and shrinkage porosity distribution were discussed in detail for the three casting processes. A smooth filling was found in all three casting processes, especially the low pressure casting exhibiting a better filling performance than the other two, but the solidification processes were different. The casting did not experience the sequential solidification, and the feeding paths were blocked, leading to shrinkage porosity defects in the riser and the bottom of the casting in gravity casting and in the upper zone of the casting in low pressure casting. While, the sequential solidification was well controlled in the solidification process of centrifugal casting, and majority of the shrinkage porosity defects can only be observed in the riser. It could be concluded that the centrifugal casting process is the most suitable casting process for the production of propeller hub body. The casting experiments verified the simulation results, and a defect-free propeller hub was obtained by centrifugal casting with a rotational speed of 150 r.in-1.

  15. Caste biology and behaviour of Bulbitermes sarawakensis (Isoptera, Nasutitermitinae) in Malaysia

    NARCIS (Netherlands)

    Lommen, S.T.E.; Huis, van A.; Sajap, A.S.

    2004-01-01

    Morphometrics, caste composition and behaviour were studied in Bulbitermes sarawakensis (Isoptera; Nasutitermitinae) in Malaysia. Morphometric studies displayed two larval stages, a presoldier and a soldier caste, two worker castes and different nymphal stages. Four different nymphs with long wings

  16. Announcement on the Ranking List of China's Large Casting Enterprises in 2005

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    @@ China is the largest country in casting production worldwide and with many excellent casting producers. Advanced manufacturing technology, scientific management ideas, enormous economic benefit in these enterprises makes them the pioneers of the national casting industry.

  17. China’s Aluminum Alloy Die Castings Industry has Promising Prospects

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

    <正>Engine aluminum alloy engine block die casting experienced rapid development in recent years. Domestic enterprises introduced large die casting machine automatic production lines, and developed large aluminum alloy die cast-

  18. 77 FR 17119 - Pipeline Safety: Cast Iron Pipe (Supplementary Advisory Bulletin)

    Science.gov (United States)

    2012-03-23

    ... Pipeline and Hazardous Materials Safety Administration Pipeline Safety: Cast Iron Pipe (Supplementary... operators of natural gas cast iron distribution pipelines and state pipeline safety representatives. Recent deadly explosions in Philadelphia and Allentown, Pennsylvania involving cast iron pipelines installed...

  19. Shallow water model for horizontal centrifugal casting

    Science.gov (United States)

    Boháček, J.; Kharicha, A.; Ludwig, A.; Wu, M.

    2012-07-01

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

  20. Prediction of Microstructure in ADI Castings

    Directory of Open Access Journals (Sweden)

    Guzik E.

    2016-12-01

    Full Text Available Tests were carried out on samples of low-alloy ductile iron with additions of Ni, Cu and Mo, subjected to austempering heat treatment. The samples were austenitized at 850, 900 and 950 °C, and then austempered at T = 210, 240, 270, 300 and 330 °C. The ausferritizing treatment was carried out in a salt bath for the time τ = 2 - 8 hours. Additionally, tests and studies covered samples subjected to the ausferritizing treatment at 270 °C with the time of holding castings in a bath from 2 to 24 hours. Evaluation covered the results of the ADI microstructure examinations and hardness measurements. The ADI matrix morphology was identified counting the average number of ausferrite plates and measuring their width and spacing. The regression equations HB = f (τ, T and τ = f (HB, T were derived to establish the, so-called, “process window”, allowing obtaining a priori the required microstructure of ADI and, consequently, the required mechanical properties, mainly hardness, shaping the functional properties of castings, abrasion wear resistance – in particular.

  1. Horizontal electromagnetic casting of thin metal sheets

    Energy Technology Data Exchange (ETDEWEB)

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

    1988-01-01

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

  2. Horizontal electromagnetic casting of thin metal sheets

    Energy Technology Data Exchange (ETDEWEB)

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

    1987-01-01

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

  3. Fracture analysis of chilled cast iron camshaft

    Directory of Open Access Journals (Sweden)

    Li Ping

    2009-05-01

    Full Text Available The fracture of a camshaft made of chilled cast iron, installed in a home-made Fukang car, happened only after running over a distance of 6,200 km. The fractured camshaft was received to conduct a series of failure analyses using visual inspection, SEM observation of fracture section, microstructure analysis, chemical composition analysis and hardness examination and so on, while those of CKD camshaft made by Citro雗 Company in France was also simultaneously analyzed to compare the difference between them. The results showed that the fracture of the camshaft mainly results from white section in macrostructure and Ledeburite in microstructure; the crack in the fractured camshaft should be recognized to initiate at the boundary of coarser needle-like carbide and matrix, and then propagate through the transverse section. At the same time, the casting defects such as dendritic shrinkage, accumulated inclusion and initiated crack and abnormal external force might stimulate the fracture of camshaft as well. Based on failure analysis, some measures have been employed, and as a result, the fracture of home-made camshafts has been effectively prevented.

  4. Fracture analysis of chilled cast iron camshaft

    Institute of Scientific and Technical Information of China (English)

    Li Ping; Li Fengjun; Cai Anke; Wei Bokang

    2009-01-01

    The fracture of a camshaft made of chilled cast iron, installed in a home-made Fukang car, happened only after running over a distance of 6,200 km. The fractured camshaft was received to conduct a series of failure analyses using visual inspection, SEM observation of fracture section, microstructure analysis, chemical composition analysis and hardness examination and so on, while those of CKD camshaft made by Citroen Company in France was also simultaneously analyzed to compare the difference between them. The results showed that the fracture of the camshaft mainly results from white section in macrostructure and Ledeburite in microstructure; the crack in the fractured camshaft should be recognized to initiate at the boundary of coarser needle-like carbide and matrix, and then propagate through the transverse section. At the same time, the casting defects such as dendritic shrinkage, accumulated inclusion and initiated crack and abnormal external force might stimulate the fracture of camshaft as well. Based on failure analysis, some measures have been employed, and as a result, the fracture of home-made camshafts has been effectively prevented.

  5. Solidification microstructure of M2 high speed steel by different casting technologies

    OpenAIRE

    Zhou Xuefeng; Fang Feng; Jiang Jianjing

    2011-01-01

    The present work investigated the solidification microstructure of AISI M2 high speed steel manufactured by different casting technologies, namely iron mould casting and continuous casting. The results revealed that the as-cast structure of the steel was composed of the iron matrix and the M2C eutectic carbide networks, which were greatly refined in the ingot made by continuous casting process, compared with that by the iron mould casting process. M2C eutectic carbides presented variation in ...

  6. Virtual Mold Technique in Thermal Stress Analysis during Casting Process

    Institute of Scientific and Technical Information of China (English)

    Si-Young Kwak; Jae-Wook Baek; Jeong-Ho Nam; Jeong-Kil Choi

    2008-01-01

    It is important to analyse the casting product and the mold at the same time considering thermal contraction of the casting and thermal expansion of the mold. The analysis considering contact of the casting and the mold induces the precise prediction of stress distribution and the defect such as hot tearing. But it is difficult to generate FEM mesh for the interface of the casting and the mold. Moreover the mesh for the mold domain spends lots of computational time and memory for the analysis due to a number of meshes. Consequently we proposed the virtual mold technique which only uses mesh of the casting part for thermal stress analysis in casting process. The spring bar element in virtual mold technique is used to consider the contact of the casting and the mold. In general, a volume of the mold is much bigger than that of casting part, so the proposed technique decreases the number of mesh and saves the computational memory and time greatly. In this study, the proposed technique was verified by the comparison with the traditional contact technique on a specimen. And the proposed technique gave satisfactory results.

  7. Casting Porosity-Free Grain Refined Magnesium Alloys

    Energy Technology Data Exchange (ETDEWEB)

    Schwam, David [Case Western Reserve University

    2013-08-12

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

  8. 25 CFR 217.6 - Method of casting votes.

    Science.gov (United States)

    2010-04-01

    ... the status quo. At the time they notify the superintendent of the votes cast on an issue, each joint... 25 Indians 1 2010-04-01 2010-04-01 false Method of casting votes. 217.6 Section 217.6 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR ENERGY AND MINERALS MANAGEMENT OF TRIBAL ASSETS...

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

    Science.gov (United States)

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

    1995-03-01

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

  10. Laser surface treatment of grey cast iron for automotive applications

    NARCIS (Netherlands)

    Ocelik, V.; Tang, P.N.; de Boer, M.C.; de Oliveira, U.; de Hosson, J.T.M.; DeHosson, JTM; Brebbia, CA; Nishida, SI

    2005-01-01

    The surface of pearlitic grey cast iron was treated using a 2 kW Nd:YAG laser beam with the final aim to improve its surface properties, mainly for automotive applications. Two kinds of laser surface treatments were experimentally applied. In the laser surface hardening approach the surface of cast

  11. Independent origins of Indian caste and tribal paternal lineages.

    Science.gov (United States)

    Cordaux, Richard; Aunger, Robert; Bentley, Gillian; Nasidze, Ivane; Sirajuddin, S M; Stoneking, Mark

    2004-02-03

    The origins of the nearly one billion people inhabiting the Indian subcontinent and following the customs of the Hindu caste system are controversial: are they largely derived from Indian local populations (i.e. tribal groups) or from recent immigrants to India? Archaeological and linguistic evidence support the latter hypothesis, whereas recent genetic data seem to favor the former hypothesis. Here, we analyze the most extensive dataset of Indian caste and tribal Y chromosomes to date. We find that caste and tribal groups differ significantly in their haplogroup frequency distributions; caste groups are homogeneous for Y chromosome variation and more closely related to each other and to central Asian groups than to Indian tribal or any other Eurasian groups. We conclude that paternal lineages of Indian caste groups are primarily descended from Indo-European speakers who migrated from central Asia approximately 3,500 years ago. Conversely, paternal lineages of tribal groups are predominantly derived from the original Indian gene pool. We also provide evidence for bidirectional male gene flow between caste and tribal groups. In comparison, caste and tribal groups are homogeneous with respect to mitochondrial DNA variation, which may reflect the sociocultural characteristics of the Indian caste society.

  12. The surface layer of austempered ductile iron investment castings properties

    OpenAIRE

    D. Myszka; M. Kłębczyk; Zych, A.; L. Kwiatkowski

    2009-01-01

    The article presents a unique process of carbonnitriding and nitriding the precision casting surfaces of austempered ductile iron. The results of the research are pointing that adequate process parameters allow to obtain multiple increase of wear resistance and a significant increase of corrosion resistance. Also, changes of cast microstructure and hardness are presented.

  13. Worker caste determination in the army ant Eciton burchellii.

    Science.gov (United States)

    Jaffé, Rodolfo; Kronauer, Daniel J C; Kraus, F Bernhard; Boomsma, Jacobus J; Moritz, Robin F A

    2007-10-22

    Elaborate division of labour has contributed significantly to the ecological success of social insects. Division of labour is achieved either by behavioural task specialization or by morphological specialization of colony members. In physical caste systems, the diet and rearing environment of developing larvae is known to determine the phenotype of adult individuals, but recent studies have shown that genetic components also contribute to the determination of worker caste. One of the most extreme cases of worker caste differentiation occurs in the army ant genus Eciton, where queens mate with many males and colonies are therefore composed of numerous full-sister subfamilies. This high intracolonial genetic diversity, in combination with the extreme caste polymorphism, provides an excellent test system for studying the extent to which caste determination is genetically controlled. Here we show that genetic effects contribute significantly to worker caste fate in Eciton burchellii. We conclude that the combination of polyandry and genetic variation for caste determination may have facilitated the evolution of worker caste diversity in some lineages of social insects.

  14. Gears castings from ductile iron of improved abrasion wear resistance

    Directory of Open Access Journals (Sweden)

    D. Kopyciński

    2011-10-01

    Full Text Available The aim of this study was to develop an industrial technological process for the manufacturing of castings from alloyed ductile iron characterized by improved resistance to abrasion wear. The outcome of the study was the implementation of developed technology under the industrial conditions of ASPAMET Foundry Plant and start up of production of a wide range of cast gears.

  15. The surface layer of austempered ductile iron investment castings properties

    Directory of Open Access Journals (Sweden)

    D. Myszka

    2009-01-01

    Full Text Available The article presents a unique process of carbonnitriding and nitriding the precision casting surfaces of austempered ductile iron. The results of the research are pointing that adequate process parameters allow to obtain multiple increase of wear resistance and a significant increase of corrosion resistance. Also, changes of cast microstructure and hardness are presented.

  16. 49 CFR 192.755 - Protecting cast-iron pipelines.

    Science.gov (United States)

    2010-10-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1999-09-30

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

  18. Development of Continuous Electrical Steel and Casting Technology of New Products

    Institute of Scientific and Technical Information of China (English)

    WANG Li-tao; DENG Chen-hong; DONG Mei; SHI Li-fa; ZHANG Jian-ping

    2012-01-01

    The development of continuous casting technology of electrical steel was analyzed. The technologies and products characteristics of conventional continuous casting, thin slab continuous casting and rolling, middle thin slab continuous casting and rolling and twin-roll thin strip were compared. Conventional continuous casting technology was widely adopted in producing electrical steel, thin slab continuous casting and rolling and middle thin slab contin- uous casting and roiling technology industrialized electrical steel~ and study of twin-roll thin strip casting technology was focused on fundamental experiments.

  19. Thermodynamic stability of austenitic Ni-Mn-Cu cast iron

    Directory of Open Access Journals (Sweden)

    A. Janus

    2014-07-01

    Full Text Available The performed research was aimed at determining thermodynamic stability of structures of Ni-Mn-Cu cast iron castings. Examined were 35 alloys. The castings were tempered at 900 °C for 2 hours. Two cooling speeds were used: furnace-cooling and water-cooling. In the alloys with the nickel equivalent value less than 20,0 %, partial transition of austenite to martensite took place. The austenite decomposition ratio and the related growth of hardness was higher for smaller nickel equivalent value and was clearly larger in annealed castings than in hardened ones. Obtaining thermodynamically stable structure of castings requires larger than 20,0 % value of the nickel equivalent.

  20. Twin-roll strip casting of magnesium alloys in China

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The development status of twin-roll strip casting for magnesium alloys in China was summarized as well as the new progress when several kinds of twin-roll strip casting technologies were developed and used.Horizontal twin-roll casting (HTRC) of magnesium alloys has attracted much attention and has been industrialized in China.Vertical twin roll casting(VTRC) of the magnesium alloys can reach a speed of higher than 30 m/min and its research and development are just beginning and exhibit exciting potential.By comparing the process characteristics of the two technologies,the process stability of HTRC for the magnesium alloys is better,and the casting speed and the cooling rate of VTRC for the magnesium alloys are higher.The quality of the products by the two technologies needs to be improved and further investigated.

  1. Waterproof casts for immobilization of children's fractures and sprains.

    Science.gov (United States)

    Shannon, Elizabeth G; DiFazio, Rachel; Kasser, James; Karlin, Lawrence; Gerbino, Peter

    2005-01-01

    This study was designed to determine the efficacy of waterproof cast-lining materials in children with short-arm, long-arm, and short-leg casts. Eligible patients had healing fractures 2 weeks after reduction, stable fractures requiring no reduction, or sprains. A total of 165 waterproof-lined casts were applied and 124 children and parents completed a survey (76.9%) upon cast removal. Results revealed 79% very satisfied, 21% satisfied, and 0% dissatisfied. There were 16 (12.9%) minor skin integrity issues. Waterproof casts in stable fractures and sprains allow acceptable immobilization with no significant associated unusual risk and allow children to resume their usual recreational water activities and hygiene regimen without risk of adverse results.

  2. DESIGN AND FABRICATION OF A CENTRIFUGAL CASTING MACHINE

    Directory of Open Access Journals (Sweden)

    Adedipe Oyewole

    2011-12-01

    Full Text Available The design and fabrication of a centrifugal casting machine was successfully carried out. The operation of the machine was based on the principle of centrifugal force. Suitable design theory, analysis and calculation were adopted carried out in the course of the work. The mold is bolted to the base plate which can rotate at moderatespeeds thereby forcing the molten metal against the inner walls of the mold. This machine could be used to cast small engineering components. The centrifugal force on the machine was determined to be 3207.3N, while the required power on the machine was 854.7W. A test was carried out on the fabricated centrifugal casting machine with aluminum alloy and the machine was able to cast 6kg of aluminum alloy and the casting was successful.

  3. Tundish Technology for Casting Clean Steel: A Review

    Science.gov (United States)

    Sahai, Yogeshwar

    2016-08-01

    With increasing demand of high-quality clean steel, cleanliness is of paramount importance in steel production and casting. Tundish plays an important role in controlling the continuously cast steel quality as it links a batch vessel, ladle, to a continuous casting mold. Tundish is also the last vessel in which metal flows before solidifying in mold. For controlling the quality of steel, flow and temperature control of the melt are critical, and these are presented in this paper. Use of proper flux, design of flow control devices, and gas injection in tundish become important factors in casting clean steel. Recycling of hot tundish, centrifugal flow tundish, H-shaped tundish, etc. are some of the developments which were implemented to cast clean steel and these are discussed.

  4. Modeling of Mold Filling and Solidification in Lost Foam Casting

    Institute of Scientific and Technical Information of China (English)

    Fengjun LI; Houfa SHEN; Baicheng LIU

    2003-01-01

    Based on the characteristics of the lost foam casting (LFC) and the artificial neural network technique, a mathematicalmodel for the simulation of the melt-pattern interface movement during the mold filling of LFC has been proposed andexperimentally verified. The simulation results are consistent with the experiments in both the shapes of melt frontand filling sequences. According to the calculated interface locations, the fluid flow and the temperature distributionsduring the mold filling and solidification processes were calculated, and the shrinkage defect of a lost foam ductileiron casting was predicted by considering the mold wall movement in LFC. The simulation method was applied tooptimize the casting design of lost foam ductile iron castings. It is shown that the model can be used for the defectsprediction and for casting design optimization in the practical LFC production.

  5. Structure and properties of stir-cast zinc alloys

    Energy Technology Data Exchange (ETDEWEB)

    LeHuy, H.; Blain J.; Masounave, J.; Bata, G.L. (Industrial Materials Research Institute, Boucherville, P.Q. (Canada))

    Stir casting (or rheocasting) of ZA-27 zinc alloys was investigated experimentally. By vigorously agitating the alloys during cooling, the dendrites that were forming were fragmented giving a unique structure composed of spherical and rosette shaped particles suspended in the remaining liquid. Under high shear rates ({center dot}{gamma} = 300s{sup {minus}1} or more) the slurries with primary particle concentrations as high as 60% displayed viscosities as low as 20 poises and could easily be casted. The effects of processing variables such as shearing and cooling rates and casting temperatures were studied. Their relative importance on the rheological and microstructural behavior of the stir cast alloys are discussed. Results from viscosity measurements on slurries show that non-dendritical ZA-27 alloys obey a power law fluid model. Finally, results from mechanical and compressive studies carried out on solidified slurries are discussed and compared to conventional casted and wrought alloy properties.

  6. Integration of CAD/CAE System for Casting Process Design

    Institute of Scientific and Technical Information of China (English)

    周舰; 荆涛

    2003-01-01

    Concurrent engineering is needed to modernize the foundry industry and to reduce the scrap from castings and thus increase the economic profit. This paper presents an integrated 3-D CAD/CAE system for a foundry using concurrent engineering which considers casting structure, casting type, and manufacturing properties in the CAD module to design the pouring system, the riser, the chill core and so on. A visualized solid model is developed for the casting component with the model design enhanced by CAE analysis. Heat transfer and fluid flow simulation are used to analyze the initial design. The whole product development process is analyzed using concurrent engineering methods. The application shows that the integrated system can improve the efficiency of the design and manufacturing process of die casting.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-12-13

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

  8. Gating of Permanent Molds for Aluminum Casting

    Energy Technology Data Exchange (ETDEWEB)

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

    2004-01-01

    This report summarizes a two-year project, DE-FC07-011D13983 that concerns the gating of aluminum castings in permanent molds. The main goal of the project is to improve the quality of aluminum castings produced in permanent molds. The approach taken was to determine how the vertical type gating systems used for permanent mold castings can be designed to fill the mold cavity with a minimum of damage to the quality of the resulting casting. It is evident that somewhat different systems are preferred for different shapes and sizes of aluminum castings. The main problems caused by improper gating are entrained aluminum oxide films and entrapped gas. The project highlights the characteristic features of gating systems used in permanent mold aluminum foundries and recommends gating procedures designed to avoid common defects. The study also provides direct evidence on the filling pattern and heat flow behavior in permanent mold castings. Equipment and procedure for real time X-Ray radiography of molten aluminum flow into permanent molds have been developed. Other studies have been conducted using water flow and behavior of liquid aluminum in sand mold using real time photography. This investigation utilizes graphite molds transparent to X-Rays making it possible to observe the flow pattern through a number of vertically oriented grating systems. These have included systems that are choked at the base of a rounded vertical sprue and vertical gating systems with a variety of different ingates into the bottom of a mold cavity. These systems have also been changed to include gating systems with vertical and horizontal gate configurations. Several conclusions can be derived from this study. A sprue-well, as designed in these experiments, does not eliminate the vena contracta. Because of the swirling at the sprue-base, the circulating metal begins to push the entering metal stream toward the open runner mitigating the intended effect of the sprue-well. Improved designs of

  9. Cast Stone Formulation At Higher Sodium Concentrations

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-10-02

    A low temperature waste form known as Cast Stone is being considered to provide supplemental Low Activity Waste (LAW) immobilization capacity for the Hanford site. Formulation of Cast Stone at high sodium concentrations is of interest since a significant reduction in the necessary volume of Cast Stone and subsequent disposal costs could be achieved if an acceptable waste form can be produced with a high sodium molarity salt solution combined with a high water to premix (or dry blend) ratio. The objectives of this study were to evaluate the factors involved with increasing the sodium concentration in Cast Stone, including production and performance properties and the retention and release of specific components of interest. Three factors were identified for the experimental matrix: the concentration of sodium in the simulated salt solution, the water to premix ratio, and the blast furnace slag portion of the premix. The salt solution simulants used in this study were formulated to represent the overall average waste composition. The cement, blast furnace slag, and fly ash were sourced from a supplier in the Hanford area in order to be representative. The test mixes were prepared in the laboratory and fresh properties were measured. Fresh density increased with increasing sodium molarity and with decreasing water to premix ratio, as expected given the individual densities of these components. Rheology measurements showed that all of the test mixes produced very fluid slurries. The fresh density and rheology data are of potential value in designing a future Cast Stone production facility. Standing water and density gradient testing showed that settling is not of particular concern for the high sodium compositions studied. Heat of hydration measurements may provide some insight into the reactions that occur within the test mixes, which may in turn be related to the properties and performance of the waste form. These measurements showed that increased sodium

  10. Cast Stone Formulation At Higher Sodium Concentrations

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-09-17

    A low temperature waste form known as Cast Stone is being considered to provide supplemental Low Activity Waste (LAW) immobilization capacity for the Hanford site. Formulation of Cast Stone at high sodium concentrations is of interest since a significant reduction in the necessary volume of Cast Stone and subsequent disposal costs could be achieved if an acceptable waste form can be produced with a high sodium molarity salt solution combined with a high water to premix (or dry blend) ratio. The objectives of this study were to evaluate the factors involved with increasing the sodium concentration in Cast Stone, including production and performance properties and the retention and release of specific components of interest. Three factors were identified for the experimental matrix: the concentration of sodium in the simulated salt solution, the water to premix ratio, and the blast furnace slag portion of the premix. The salt solution simulants used in this study were formulated to represent the overall average waste composition. The cement, blast furnace slag, and fly ash were sourced from a supplier in the Hanford area in order to be representative. The test mixes were prepared in the laboratory and fresh properties were measured. Fresh density increased with increasing sodium molarity and with decreasing water to premix ratio, as expected given the individual densities of these components. Rheology measurements showed that all of the test mixes produced very fluid slurries. The fresh density and rheology data are of potential value in designing a future Cast Stone production facility. Standing water and density gradient testing showed that settling is not of particular concern for the high sodium compositions studied. Heat of hydration measurements may provide some insight into the reactions that occur within the test mixes, which may in turn be related to the properties and performance of the waste form. These measurements showed that increased sodium

  11. Cast Stone Formulation At Higher Sodium Concentrations

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-02-28

    A low temperature waste form known as Cast Stone is being considered to provide supplemental Low Activity Waste (LAW) immobilization capacity for the Hanford site. Formulation of Cast Stone at high sodium concentrations is of interest since a significant reduction in the necessary volume of Cast Stone and subsequent disposal costs could be achieved if an acceptable waste form can be produced with a high sodium molarity salt solution combined with a high water to premix (or dry blend) ratio. The objectives of this study were to evaluate the factors involved with increasing the sodium concentration in Cast Stone, including production and performance properties and the retention and release of specific components of interest. Three factors were identified for the experimental matrix: the concentration of sodium in the simulated salt solution, the water to premix ratio, and the blast furnace slag portion of the premix. The salt solution simulants used in this study were formulated to represent the overall average waste composition. The cement, blast furnace slag, and fly ash were sourced from a supplier in the Hanford area in order to be representative. The test mixes were prepared in the laboratory and fresh properties were measured. Fresh density increased with increasing sodium molarity and with decreasing water to premix ratio, as expected given the individual densities of these components. Rheology measurements showed that all of the test mixes produced very fluid slurries. The fresh density and rheology data are of potential value in designing a future Cast Stone production facility. Standing water and density gradient testing showed that settling is not of particular concern for the high sodium compositions studied. Heat of hydration measurements may provide some insight into the reactions that occur within the test mixes, which may in turn be related to the properties and performance of the waste form. These measurements showed that increased sodium

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

    Science.gov (United States)

    Stoddard, Nathan G

    2015-02-10

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

  13. Recent Development of Lost Foam Casting Technology Comment on the 7th Chinese Lost Foam Casting Symposium

    Institute of Scientific and Technical Information of China (English)

    LIU Zi-li

    2006-01-01

    @@ The 7th Chinese Lost Foam Casting (LFC) Symposium & the 1st LFC Technology Exposition were held on May 21-23 at Nanjing University of Aeronautics and Astronautics (NUAA), and the conference theme . was "Recent development of lost foam casting technology".

  14. Effects of casting speed on microstructure and segregation of electromagnetically stirred Aluminum alloy in continuous casting process

    Institute of Scientific and Technical Information of China (English)

    LEE Dock-Young; KANG Suk-Won; CHO Duck-Ho; KIM Ki-Bae

    2006-01-01

    Recently, a semi-solid metal processing has been acknowledged as a cost-effective technique to be able to manufacture high quality product for the transportation industry.In this study a hypo-eutectic Al alloy was fabricated by means of an electromagnetic stirrer in continuous casting process and the microstructural change during solidification due to a fluid flow by electromagnetic stirring was examined.Due to the forced fluid flow during solidification a dendritic phase of primary α phase of Al alloy was turned into a globular phase, which can make the Al alloy get a thixotropic behavior in the semi-solid region.In order to establish the quantitative relationship between microstructure and the process parameters, the morphology shape, a silicon distribution and a size of primary α phase were observed according to casting speed in continuous casting machine.The primary α phase was turned into the degenerate dendrites approaching a spherical configuration with increasing casting speed.The fine-grained and equiaxed microstructure appeared at higher casting speed.A segregation behavior of Si element was declined with increasing casting speed and a very uniform distribution of Si element was observed on the billet at a casting speed of 600 mm·min-1.A thickness of the solidifying shell of the billet was shortened with increasing the casting speed.

  15. Casting defects of Ti-6Al-4V alloy in vertical centrifugal casting processes with graphite molds

    Science.gov (United States)

    Jia, Limin; Xu, Daming; Li, Min; Guo, Jingjie; Fu, Hengzhi

    2012-02-01

    Numerical simulation and experimental investigation are utilized to analyze the casting defects of Ti-6Al-4V alloy formed under different vertical centrifugal casting conditions in graphite molds. Mold rotating rates of 0, 110 and 210 rpm are considered in experimental process. Results show that centrifugal forces have significant effects on the quantity of both macropores and microdefects (micropores, microcracks and inclusions). The relative amount of all macro- and micro-scopic casting defects decreases from 62.4 % to 24.8 % with the increasing of the centrifugal force, and the macropore quantity in stepped casting decreases exponentially with the increase of the gravitation coefficient. The relative proportions of both micropores and microcracks decrease with the mold-rotating rate increase, but the relative proportion of inclusions increases significantly. Besides this, the mold-filling sequence is proved to be an important factor in casting quality control.

  16. Microstructure and Property of Hypereutectic High Chromium Cast Iron Prepared by Slope Cooling Body-Centrifugal Casting Method

    Institute of Scientific and Technical Information of China (English)

    Zhifu HUANG; Jiandong XING; Anfeng ZHANG

    2006-01-01

    In this paper, the ring-type ingot of hypereutectic high Cr cast iron was obtained by slope cooling bodycentrifugal casting method (SC-CCM), and its microstructure and impact toughness were investigated, respectively. The results indicated that, first, the primary carbides in the microstructure are prominently finer than those in the hypereutectic high Cr cast iron prepared by conventional casting method. Second, in the ring-type ingot, the primary carbides near radial outer field are finer than those near radial inner field; furthermore, there is dividing field in the microstructure. Finally, the impact toughness values of the specimens impacted on the radial outer face and on the radial inner face are improved respectively about 36% and 138%more than that of the hypereutectic high Cr one prepared by conventional casting method.

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

    Directory of Open Access Journals (Sweden)

    Lim Sang-Sub

    2014-12-01

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

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

    Science.gov (United States)

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

    2014-12-01

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

  19. Thickness control and interface quality as functions of slurry formulation and casting speed in side-by-side tape casting

    DEFF Research Database (Denmark)

    Bulatova, Regina; Jabbari, Mirmasoud; Kaiser, Andreas;

    2014-01-01

    A novel method of co-casting called side-by-side tape casting was developed aiming to form thin functionally graded films with varying properties within a single plane. The standard organic-based recipe was optimized to co-cast slurries into thick graded tapes. Performed numerical simulations...... identified the stable flow beneath the blade with a shear rate profile independent of slurry viscosity as long as the slurry load in the casting tank was low. Thickness and interface shape could be well predicted if the rheological behaviour of slurries is known and the processing parameters are well......-controlled. A well-defined steep interface was obtained by co-casting slurries with similar viscosities above 4000mPas at a speed of 40cm/min. The elastic properties of green tapes were proven to be defined by the binder concentration in the recipe formulation. The interfaces in graded tapes were shown to withstand...

  20. 电机机座铸件的消失模铸造%Lost Foam Casting for Motor Block Castings

    Institute of Scientific and Technical Information of China (English)

    吴志超; 叶升平; 胡国良; 常湫生

    2001-01-01

    针对出口电机机座铸件,简要介绍了其消失模模具设计、成型发泡及铸件的浇注试验情况,确定了合适的铸造工艺参数,生产出了合格的铸件,证实了消失模铸造工艺生产电机机座铸件的可行性。%The design of lost foam die, pattern molding process, and pouring experiment of exported motor block casting were studied. The pertient casting technological parameters were determined. Qualified casting was made successfully, which testified the feasibility using lost foam casting to manufacture motor block casting.

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

    Science.gov (United States)

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

    2011-12-01

    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.

  2. Micro precision casting based on investment casting for micro structures with high aspect ratio

    Institute of Scientific and Technical Information of China (English)

    YANG Chuang; LI Bang-sheng; REN Ming-xing; FU Heng-zhi

    2009-01-01

    Microcasting is one of the significant technologies for the production of metallic micro parts with high aspect ratio (ratio of flow length to diameter). A micro precision casting technology based on investment casting using centrifugal method was investigated. The micro parts of Zn-4%Al alloy with an aspect ratio up to 200 was produced at the centrifugal speed of 1 500 r/min and the mold temperature of 270 ℃. The investigations on the relationship between flow length and rotational speed were carried out. For microcasting, the flow length is not only dependent on the centrifugal speed under the constant centrifugal radius, but also on the preheating temperature of mold. The flow length increases as the rotational speed and the mold temperature increase, and is much higher at a mold temperature of 270 ℃ than at other mold temperatures.

  3. Technology development for thin strip metal casting, Phase 2: Final technical report. [Melt spinning or planar flow casting

    Energy Technology Data Exchange (ETDEWEB)

    Williams, R.S.

    1988-03-07

    The Phase II program has been conducted by a team of engineers from Westinghouse Electric Corporation and Armco, Inc., with the objective of providing a suitably sized experimental planar flow casting machine, and using it to perform casting trials to address the above technical uncertainties for cast thicknesses and speeds representative of industrial production, and with sufficient duration to diminish thermal transient effects. A nominally 7 ft. diameter water-cooled copper wheel planar flow casting system has been designed, fabricated and installed in a dedicated 15,000 sq. ft. foundry facility are Armco Inc., Middletown, Ohio. This system is capable of casting 3 in. wide strip and operating at surface speeds up to 25 ft/sec. Additionally, the facility also contains a 16 in. diameter water-cooled wheel with interchangeable casting substrates of different materials. This small wheel facility has been adapted to utilize the melt overflow process for casting of 3 in. wide strip. These casting facilities are supported by a 500 lb. induction melting furnace and necessary liquid steel handling equipment. Adequate techniques have been developed for transportation and filtering of liquid steel without undue temperature loss. Good control of the planar flow casting process was not achieved during this program, however given such control and the adoption of clean steel practices, the inference is that the process will be capable of producing strip which is readily cold-rollable in the as-cast condition. After cold rolling and annealing, such material should have useful mechanical properties. 8 refs., 112 figs., 10 tabs.

  4. Biomimetic Membrane Arrays on Cast Hydrogel Supports

    DEFF Research Database (Denmark)

    Roerdink-Lander, Monique; Ibragimova, Sania; Rein Hansen, Christian;

    2011-01-01

    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...

  5. Modeling wear of cast Ti alloys.

    Science.gov (United States)

    Chan, Kwai S; Koike, Marie; Okabe, Toru

    2007-05-01

    The wear behavior of Ti-based alloys was analyzed by considering the elastic-plastic fracture of individual alloys in response to the relevant contact stress field. Using the contact stresses as the process driving force, wear was computed as the wear rate or volume loss as a function of hardness and tensile ductility for Ti-based cast alloys containing an alpha, alpha+beta or beta microstructure with or without the intermetallic precipitates. Model predictions indicated that wear of Ti alloys increases with increasing hardness but with decreasing fracture toughness or tensile ductility. The theoretical results are compared with experimental data to elucidate the roles of microstructure in wear and contrasted against those in grindability.

  6. The CERN axion solar telescope (CAST)

    Energy Technology Data Exchange (ETDEWEB)

    Aalseth, C.E.; Arik, E.; Autiero, D.; Avignone, F.T.; Barth, K.; Bowyer, S.M.; Brauninger, H.; Brodzinski, R.L.; Carmona, J.M.; Cebrian, S.; Celebi, G.; Cetin, S.; Collar, J.I.; Creswick, R.; Delbart, A.; Delattre, M.; DiLella, L.; De Oliveira, R.; Eleftheriadis, Ch.; Erdutan, N.; Fanourakis, G.; Farach, H.A.; Fiorini, C.; Geralis, Th.; Giomataris, I.; Girard, T.A.; Gninenko, S.N.; Golubev, N.A.; Hasinoff, M.; Hoffmann, D.; Irastorza, I.G.; Jacoby, J.; Jeanneau, F.; Knopf, M.A.; Kovzelev, A.V.; Kotthaus, R.; Krcmar, M.; Krecak, Z.; Lakic, B.; Liolios, A.; Ljubicic, A.; Lutz, G.; Longoni, A.; Luzon, G.; Mailov, A.; Matveev, V.A.; Miley, H.S.; Morales, A.; Morales, J.; Mutterer, M.; Nikolaidis, A.; Nussinov, S.; Ortiz, A.; Pitts, W.K.; Placci, A.; Postoev, V.E.; Raffelt, G.G.; Riege, H.; Sampieto, M.; Sarsa, M.; Savvidis, I.; Stipcevic, M.; Thomas, C.W.; Thompson, R.C.; Valco, P.; Villar, J.A.; Villierme, B.; Walckiers, L.; Wilcox, W.; Zachariadou, K.; Zioutas, K

    2002-07-01

    A decommissioned LHC test magnet is being prepared as the CERN Axion Solar Telescope (CAST) experiment. The magnet has a field of 9.6 Tesla and length of 10 meters. It is being mounted on a platform to track the sun over {+-}8 deg. vertically and {+-}45 deg. , horizontally. A sensitivity in axion-photon coupling g{alpha}{gamma}{gamma} < 5 x 10{sup -11}GeV{sup -1} can be reached for m{sub {alpha}} {<=} 10{sup -2}eV, and with a gas filled tube-can reach g{alpha}{gamma}{gamma} {<=} 10{sup -10}GeV{sup -1} for axion masses m{sub {alpha}} < 2eV.

  7. MotionCast for mobile wireless networks

    CERN Document Server

    Wang, Xinbing

    2013-01-01

    MotionCast for Mobile Wireless Networks provides an overview on the research for mobile ad-hoc networks regarding capacity and connectivity. Wireless ad-hoc networks are useful when there is a lack of infrastructure for communication. The proposed notion “MotionCast” is for the capacity analysis of multicast in MANET. A new kind of connectivity (k;m)-connectivity, is also defined, and its critical transmission range for i.i.d. (independently and identically distributed) and random walk mobility models are derived respectively. This book also investigates the related issues of connectivity in mobile and static circumstances. In addition, it provides a survey of the capacity scaling research, which gives a good summary of this field.

  8. Numerical simulation of centrifugal casting of pipes

    Science.gov (United States)

    Kaschnitz, E.

    2012-07-01

    A numerical simulation model for the horizontal centrifugal pipe casting process was developed with the commercial simulation package Flow3D. It considers - additionally to mass, energy and momentum conservation equations and free surface tracking - the fast radial and slower horizontal movement of the mold. The iron inflow is not steady state but time dependent. Of special importance is the friction between the liquid and the mold in connection with the viscosity and turbulence of the iron. Experiments with the mold at controlled revolution speeds were carried out using a high-speed camera. From these experiments friction coefficients for the description of the interaction between mold and melt were obtained. With the simulation model, the influence of typical process parameters (e.g. melts inflow, mold movement, melt temperature, cooling media) on the wall thickness of the pipes can be studied. The comparison to results of pipes from production shows a good agreement between simulation and reality.

  9. Stability condition of semisolid continuous casting process

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The major unsteady phenomena in semisolid continuous casting process are the breakage and breakout. The essential reasons for them are the passageway blocking or the solidified shell too thin to endure the withdrawal force because of the remained shell formed at the beginning and its developing afterwards. Through theoretically analyzing the crack filling and the remained shell developing, stability conditions were presented. The essential one of them is that the stress acted on the semisolid slurry must be larger than the yield stress of it. The condition without breakage is to build a balance between the increase of the remained shell resulted in solidifying and the decrease of it resulted in flowing of the semisolid slurry. The condition without breakout is to ensure the solidified thickness larger than the safe thickness. The corresponding mathematical formulas of these conditions were set up and the verification experiments show that these conditions are reliable in applications.

  10. Modelling of Tape Casting for Ceramic Applications

    DEFF Research Database (Denmark)

    Jabbari, Masoud

    Functional ceramics find use in many different applications of great interest, e.g. thermal barrier coatings, piezoactuators, capacitors, solid oxide fuel cells and electrolysis cells, membranes, and filters. It is often the case that the performance of a ceramic component can be increased markedly...... if it is possible to vary the relevant properties (e.g. electrical, electrochemical, or magnetic) in a controlled manner along the extent of the component. Such composites in which ceramic layers of different composition and/or microstructure are combined provide a new and intriguing dimension to the field...... of functional ceramics research. Advances in ceramic forming have enabled low cost shaping techniques such as tape casting and extrusion to be used in some of the most challenging technologies. These advances allow the design of complex components adapted to desired specific properties and applications. However...

  11. CENTER FOR ADVANCED SEPARATION TECHNOLOGY (CAST) PROGRAM

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Roe-Hoan; Hull, Christopher

    2014-09-30

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

  12. Design Of A Sand Casting Method Using Patterns Made Of Sublime Materials For Casting Intricate Shapes.

    Directory of Open Access Journals (Sweden)

    Sameer Rafiq Shah

    2016-02-01

    Full Text Available In today’s world every product ranging from a safety pin to huge complex aircraft engines are all manufactured by various manufacturing techniques. It involves various processes like casting, forming, machining, welding etc. Complex machines have numerous parts and elements which may be asymmetric; irregular shaped and might have a different cross-sectional profile. Manufacturing these complex and intricate shaped components to required dimensional accuracy and good surface finish is a tough task and requires use of various processes like machining, bending etc. This induces some amount of residual stresses in the machine component, and thereby makes it more susceptible to catastrophic failure. To minimize these losses and produce irregular shaped components more efficiently, a unique sand casting process is explained in this paper which makes use of a pattern made of sublime material which when burnt, produces a hollow cavity where the molten metal is poured and the casting is performed. This method eliminates the use of additional finishing processes and gives a good surface finish to the final machine components.

  13. Solidification science in cast MMCs: The influence of merton flemings

    Science.gov (United States)

    Rohatgi, Pradeep; Asthana, Rajiv

    2001-09-01

    The solidification science of cast metalmatrix composites (MMC) evolved as a subset of the broad field of solidification of monolithic alloys pioneered by Merton Flemings and his students. As a result of advances in solidification, the cast MMC field has evolved from its early incarnation—employing empirical research to engineer novel materials using versatile and cost-effective casting techniques—to using solidification-science-based approaches to tailor advanced materials for application-specific needs. The current and emerging applications of cast MMCs in a variety of automotive, aerospace, electronic packaging, and consumer-good industries exemplify the maturity of the field and the materials. Innovations in composite-forming techniques and efforts at wider industrial acceptance of MMCs will undoubtedly continue. However, the scientific principles underlying the solidification microstructure evolution that governs the composite properties have become well established, to a great extent, due to Flemings’ early, pioneering work on monolithic alloys and some of his more recent studies on solidification of reinforced metals. This paper reviews some aspects of solidification of discontinuously reinforced cast metals that owe their current understanding to Flemings’ contributions, in particular, the scientific understanding of macro- and microsegregation, fluidity and rheology of multiphase slurries, and stircasting, semi-solid casting, and preform infiltration. Current research to develop and test prototype components made from cast composites, including Al-flyash, Cu-graphite, Al-graphite, Al-alumina, and SiC-Al, is also presented, along with directions for future research.

  14. Microstructure formation and properties of abrasion resistant cast steel

    Directory of Open Access Journals (Sweden)

    S. Parzych

    2010-01-01

    Full Text Available The so-called adamitic cast steels are characterised by a high abrasion resistance. These cast steels are of a pearlitic matrix with uniformly distributed hypereutectoid cementite precipitates. Apart from hypereutectoid cementite very often transformed ledeburite also occurs in the microstructure of these cast steels. Such cast steels contain chromium (app. 1 % and nickel (app. 0.5 % as alloy additions and sometimes their silicon content is increased. The presence of molybdenum is also permissible (app. 0.4 %. The basic problem in application of these steels for structural elements constitutes their insufficient crack resistance. An improvement of mechanical properties by changes of morphology of hypereutectoid cementite and transformed ledeburite precipitates by means of the heat treatment application was the aim of this study. G200CrNiMo4-3-3 cast steel was the investigated material. Changes in the morphology of hypereutectoid cementite and transformed ledeburite obtained due to the heat treatment are described in detail in the present paper. An influence of the microstructure changes on impact toughness of the investigated cast steel is presented. Investigations performed within this study will serve for the microstructure optimisation on account of functional qualities of this cast steel.

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

    Energy Technology Data Exchange (ETDEWEB)

    Williams, R.S.

    1994-04-01

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

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

    Science.gov (United States)

    Krishna, Prasad

    2001-08-01

    With the emerging demand for energy efficient and environment-friendly automobiles, cast aluminum alloys are increasingly being used in their manufacture. In this context, two permanent mold casting processes, namely, Squeeze Cast Permanent Mold and Low Pressure Permanent Mold (LPPM) have become very popular in the production of high integrity shape-cast aluminum components. However, many industries are yet to benefit from the full potential of these processes due to limited understanding of the effect of process parameters on casting quality and the necessary boundary conditions for computer modeling and simulation so as to minimize costly field trials. This dissertation attempts to address some of these concerns facing today's foundry industry. An experimental investigation of the Indirect Squeeze Casting Process was conducted by pouring molten Al-7Si-0.3Mg (A356) alloy into a specially designed and instrumented mold, mounted on a horizontal clamped-vertical shot squeeze caster (HVSC). Temperature measurements close to the metal/mold interface were made and compared with the results of the numerical simulation of heat flow during solidification and cooling of castings. The Heat Transfer Coefficient (HTC), a critical parameter essential for any solidification simulation, was estimated based on the simulation that gave the best fit to the experimental temperature data. During the solidification process, the HTC is relatively uniform over the entire casting and on reaching a critical solidification pressure, the HTC is close to 4500 W/m2 K. The work has also provided a correlation of Secondary Dendrite Arm Spacing (SDAS) with cooling rate for a modified A356 alloy. Low Pressure Permanent Mold Casting experiments were conducted by pouring a nearly identical aluminum alloy into an instrumented, coated mold mounted on a low pressure casting machine. The pressure levels, along with the time required to achieve complete filling, were microprocessor controlled in the

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

    Energy Technology Data Exchange (ETDEWEB)

    Sabau, Adrian S [ORNL

    2008-04-01

    Efforts during Phase III focused mainly on the shell-alloy systems. A high melting point alloy, 17-4PH stainless steel, was considered. The experimental part of the program was conducted at ORNL and commercial foundries, where wax patterns were injected, molds were invested, and alloys were poured. Shell molds made of fused-silica and alumino-silicates were considered. A literature review was conducted on thermophysical and thermomechanical properties alumino-silicates. Material property data, which were not available from material suppliers, was obtained. For all the properties of 17-4PH stainless steel, the experimental data available in the literature did not cover the entire temperature range necessary for process simulation. Thus, some material properties were evaluated using ProCAST, based on CompuTherm database. A comparison between the predicted material property data and measured property data was made. It was found that most material properties were accurately predicted only over several temperature ranges. No experimental data for plastic modulus were found. Thus, several assumptions were made and ProCAST recommendations were followed in order to obtain a complete set of mechanical property data at high temperatures. Thermal expansion measurements for the 17-4PH alloy were conducted during heating and cooling. As a function of temperature, the thermal expansion for both the alloy and shell mold materials showed different evolution on heating and cooling. Numerical simulations were performed using ProCAST for the investment casting of 17-4PH stainless steel parts in fused silica molds using the thermal expansion obtained on heating and another one with thermal expansion obtained on cooling. Since the fused silica shells had the lowest thermal expansion properties in the industry, the dewaxing phase, including the coupling between wax-shell systems, was neglected. The shell mold was considered to be a pure elastic material. The alloy dimensions were

  18. The Properties of Ammonium Dinitramine (ADN): Part 2: Melt Casting

    Science.gov (United States)

    Hahma, A.; Edvinsson, H.; Östmark, H.

    2010-04-01

    A melt casting technique for ammonium dinitramine (ADN) and ADN/aluminum was developed. ADN proved relatively easy to cast, when 1% of magnesium oxide was used as a stabilizer and crystallization kernels. Densities of ADN/MgO 99/1 were 92 to 97% of theoretical mean density (TMD) and those of ADN/Al/MgO 64/35/1 were between 95 and 99% of TMD. Sedimentation of Al in the melt was prevented and the particle wetting was ensured by selecting a suitable particle size for Al. No gelling agents or other additives were used. The casting process and factors influencing it are discussed.

  19. Simulation research on control algorithm of differential pressure casting process

    Institute of Scientific and Technical Information of China (English)

    Chai Yan; Jie Wanqi; Yang Bo

    2009-01-01

    To improve the precision of the filling pressure curve of differential pressure casting controlled with PID controller,the model of differential pressure casting process is established and two pressure-difference control systems using PID algorithm and Dahlin algorithm are separately designed in MATLAB. The scheduled pressure curves controlled with PID algorithm and Dahlin algorithm,respectively,are comparatively simulated in MATLAB.The simulated pressure curves obtained show that the control precision with Dahlin algorithm is higher than that with PID algorithm in the differential pressure casting process,and it was further verified by production practice.

  20. New Approaches to Aluminum Integral Foam Production with Casting Methods

    Directory of Open Access Journals (Sweden)

    Ahmet Güner

    2015-08-01

    Full Text Available Integral foam has been used in the production of polymer materials for a long time. Metal integral foam casting systems are obtained by transferring and adapting polymer injection technology. Metal integral foam produced by casting has a solid skin at the surface and a foam core. Producing near-net shape reduces production expenses. Insurance companies nowadays want the automotive industry to use metallic foam parts because of their higher impact energy absorption properties. In this paper, manufacturing processes of aluminum integral foam with casting methods will be discussed.

  1. CovertCast: Using Live Streaming to Evade Internet Censorship

    Directory of Open Access Journals (Sweden)

    McPherson Richard

    2016-07-01

    Full Text Available We design, implement, and evaluate CovertCast, a censorship circumvention system that broadcasts the content of popular websites in real-time, encrypted video streams on common live-streaming services such as YouTube. CovertCast does not require any modifications to the streaming service and employs the same protocols, servers, and streaming software as any other user of the service. Therefore, CovertCast cannot be distinguished from other live streams by IP address filtering or protocol fingerprinting, raising the bar for censors.

  2. Family (oikos Evangelism for reaching forward caste Hindus in India

    Directory of Open Access Journals (Sweden)

    DW Fowlkes

    2006-09-01

    Full Text Available This article acknowledges the need for Church Planting Movements among the unreached peoples of India. Of particular concern to this study is the application of Church Planting Movement strategy to forward caste Hindus of India. It is shown that evangelizing households (family or �oikos� evangelism is a New Testament strategy and the most appropriate strategy for reaching forward caste Hindus. It is concluded that Christian disciples remaining within Hindu culture and familial systems hold the potential for the most indigenous approach to evangelizing forward caste Hindus.

  3. Rheology of composite solid propellants during motor casting

    Science.gov (United States)

    Rogers, C. J.; Smith, P. L.; Klager, K.

    1978-01-01

    In a study conducted to evaluate flow parameters of uncured solid composite propellants during motor casting, two motors (1.8M-lb grain wt) were cast with a PBAN propellant exhibiting good flow characteristics in a 260-in. dia solid rocket motor. Attention is given to the effects of propellant compositional and processing variables on apparent viscosity as they pertain to rheological behavior and grain defect formation during casting. It is noted that optimized flow behavior is impaired with solid propellant loading. Non-Newtonian pseudoplastic flow is observed, which is dependent upon applied shear stress and the age of the uncured propellant.

  4. Filler metal alloy for welding cast nickel aluminide alloys

    Science.gov (United States)

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

    1998-03-10

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

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

    Science.gov (United States)

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

    2015-12-01

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

  6. Environmental perspectives on using cast seaweed for biogas production

    DEFF Research Database (Denmark)

    Fredenslund, Anders Michael; Møller, Henrik Bjarne; Christensen, Thomas Budde

    Solrød Municipality, Denmark is working towards building a biogas plant utilizing locally available organic wastes including cast seaweed, which is collected each year, since the local inhabitants see this material as a nuisance. A preliminary study suggested favorable conditions for contstructing...... a mixed substrate biogas plant. Continuously fed reactor experiments showed that the intended mix of substrate including cast seaweed could be used as raw material for a biogas plant in thermophilic operation. The environmental analysis suggests existence of several positive benefits of utilizing cast...

  7. Carbides in Nodular Cast Iron with Cr and Mo

    Directory of Open Access Journals (Sweden)

    S. Pietrowski

    2007-07-01

    Full Text Available In these paper results of elements microsegregation in carbidic nodular cast iron have been presented. A cooling rate in the centre of the cross-section and on the surface of casting and change of moulding sand temperature during casting crystallization and its self-cooling have been investigated. TDA curves have been registered. The linear distribution of elements concentration in an eutectic grain, primary and secondary carbides have been made. It was found, that there are two kinds of carbides: Cr and Mo enriched. A probable composition of primary and secondary carbides have been presented.

  8. Solute distribution in columnar crystal zone of continuous casting billets

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The periodic bending deformation in the direction of casting occurs at the liquid/solid interface of billet due to the roller supporting force and the pressure of molten metal in the process of continuous casting. Based on this fact, a qualitative expression of solute concentration in columnar crystal zone for continuous casting billet is established, which agrees with the experimental results basically. Therefore, it is favorable to gain a columnar structure with less segregation by adopting a caster with compactly distributed small rollers and enhancing the cooling intensity in secondary-cooling zone.

  9. Evolution of microstructure in centrifugal cast Al-Cu alloy

    Directory of Open Access Journals (Sweden)

    Sui Yanwei

    2010-02-01

    Full Text Available In this research, the effects of centrifugal radius and mould rotation speed on microstructure in centrifugal-cast Al-Cu alloy have been investigated. The results show that, with increase of the centrifugal radius or mould rotation speed, the grain size of centrifugal-cast Al-Cu alloy decreases gradually, while the content of white phases containing the Al2Cu precipitated from α-phase, divorced eutectic and regular eutectic microstructure increases, leading to higher Cu macrosegregation. The variation level of microstructure in centrifugal-cast Al-Cu alloy at 600 rpm of mould rotation speed is greater than that at 300 rpm.

  10. The studies of nodular graphite cast iron early stages austempering

    OpenAIRE

    A. Krzyńska; M. Kaczorowski

    2008-01-01

    The results of early stage of ductile cast iron austempering are presented. The aim of the investigations was to look closer into the structure – mechanical properties relationships of this very attractive cast material. The experiment was carried out with enriched with Cu EN-GJS-500-7 grade ductile iron. The specimens were first solution heat treated 1 hour in 910oC and then isothermally quenched for different time in molten tin at the temperature 275oC. The mechanical properties of as cast ...

  11. High speed twin roll casting of 6016 strip

    OpenAIRE

    Haga, T.; Ikawa, M; H.Watari; S. Kumai

    2006-01-01

    Purpose: of this paper is to clear the possibility of high speed roll casting of thin aluminum alloy strip. 6016aluminum alloy is used for sheet metal of the automobile. Therefore, casting of 6016 was tried in this study.Castability and characteristics of roll cast 6016 strip were investigated.Design/methodology/approach: was a high speed twin roll caster. The high speed twin roll caster was designedto overcome the low castability of the twin roll caster.Findings: are as below. The 6016 could...

  12. Study on heat treatment blister of squeeze casting parts

    Institute of Scientific and Technical Information of China (English)

    TONG Wen-jun; QI Lin; QI Pi-xiang

    2007-01-01

    Heat treatment blister is one of the common defects found in squeeze casting parts, which is related to squeeze mode, process and mold. For direct squeeze-casting parts, solution heat treatment can be performed smoothly as long as oil-based paint is not used and air exhaust is well arranged. For indirect squeeze casting parts,solution heat treatment can also be applied when additional factors are taken into consideration, including well designed internal feeding system and strictly controlled liquid metal filling velocity to prevent from inclusions.

  13. Dynamic control of crystallinity in polymer film casting process

    Directory of Open Access Journals (Sweden)

    Thananchai Leephakpreeda

    2005-05-01

    Full Text Available This paper presents an approach for dynamic control of crystallinity in polymer film casting process. As known, the transients of crystallization dictate the microstructures of semi-crystalline polymer during solidification. In turn, the properties of finished products can be determined by adjustable variables in polymer film casting process such as temperature of chill roll. In this work, an experimental model of the solidification in film casting process is derived by a system identification technique. This model is used to design a digital feedback controller including a state estimator. The simulation results show the effectiveness of the proposed control technique on an extruded film.

  14. Water Modeling of Twin-Roll Strip Casting

    Institute of Scientific and Technical Information of China (English)

    WANG Bo; ZHANG Jie-yu; FAN Jun-fei; ZHAO Shun-li; FANG Yuan; AN Sheng-li

    2006-01-01

    Twin-roll strip casting is regarded as a prospective technology of near net shape continuous casting. The fluid flow field and level fluctuation in the pool have a strong influence not only on composition and temperature homogeneity of pool, but also on the strip quality. A 1∶1 water model of a twin-roll strip caster was set up based on the criteria of Froude number and Reynold number similarity. The level fluctuation was measured. The influence of pool depth, casting speed and feeding system configuration on level fluctuation in the pool was studied. The experimental results provided a basis for the optimization of feeding system and process parameters.

  15. Working-class royalty: bees beat the caste system.

    Science.gov (United States)

    Wenseleers, Tom; Ratnieks, Francis L W; de F Ribeiro, Marcia; de A Alves, Denise; Imperatriz-Fonseca, Vera-Lucia

    2005-06-22

    The struggle among social classes or castes is well known in humans. Here, we show that caste inequality similarly affects societies of ants, bees and wasps, where castes are morphologically distinct and workers have greatly reduced reproductive potential compared with queens. In social insects, an individual normally has no control over its own fate, whether queen or worker, as this is socially determined during rearing. Here, for the first time, we quantify a strategy for overcoming social control. In the stingless bee Schwarziana quadripunctata, some individuals reared in worker cells avoid a worker fate by developing into fully functional dwarf queens.

  16. Interaction between alloying and hardening of cast iron surface

    Institute of Scientific and Technical Information of China (English)

    刘政军; 郝雪枫; 傅迎庆; 牟力军

    2002-01-01

    To improve wear resistance of surface will increase the service life of gray cast iron directly. This paper presents that gray cast iron surface coated with alloy powder is locally remelted by TIG arc to increase the wear resistance. The influences of arc current and scanning rate etc on surface properties are found. Under different conditions, the microstructure, hardness and wear resistance of remelted layer are analyzed and measured. The results indicate that the gray cast iron surface can be strengthened by TIG arc local remelting treatment. Especially, surface alloying hardening effect is best and surface properties are improved remarkably.

  17. STUDY KOMPARASI LOST FOAM DAN KONVENSIONAL CASTING PRODUK DISC BRAKE

    OpenAIRE

    Yoso, Sumeru; -, Suyitno

    2014-01-01

    Disc brake component is a vital component with gray cast iron base material, it’s also fast lasting wearing part, so it has be replaced often. The disc brake replacement component in a local market is being supplied by the small scale local metal casting industries have the same quality as the genuine part.Disc brake making process is utilizing casting method inserting RCS core between drag and coup, than metal molten poured inside mold. The problem of this method is the product result often ...

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

    Science.gov (United States)

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

    2012-12-01

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

  19. Caste, Class and the Love-Marriage: Social Change in India

    Science.gov (United States)

    Corwin, Lauren A.

    1977-01-01

    The present study of a small town in rural West Bengal, India, reveals a number of "love-marriages" involving individuals from castes of distinctly different ranks in the local caste hierarchy. Despite the prevailing rule of caste endogamy, inter-caste couples appear to face little difficulty. (Author)

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

    Energy Technology Data Exchange (ETDEWEB)

    Piwonka, T.S. [ed.

    1996-01-01

    This report details results of a 30-month program to develop methods of making clean ferrous castings, i.e., castings free of inclusions and surface defects. The program was divided into 3 tasks: techniques for producing clean steel castings, electromagnetic removal of inclusions from ferrous melts, and study of causes of metal penetration in sand molds in cast iron.

  1. 46 CFR 59.20-1 - Carbon-steel or alloy-steel castings.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Carbon-steel or alloy-steel castings. 59.20-1 Section 59... BOILERS, PRESSURE VESSELS AND APPURTENANCES Welding Repairs to Castings § 59.20-1 Carbon-steel or alloy-steel castings. Defects in carbon-steel or alloy-steel castings may be repaired by welding. The...

  2. 40 CFR 464.20 - Applicability; description of the copper casting subcategory.

    Science.gov (United States)

    2010-07-01

    ... introduction of pollutants into publicly owned treatment works resulting from copper casting operations as... copper casting subcategory. 464.20 Section 464.20 Protection of Environment ENVIRONMENTAL PROTECTION... Copper Casting Subcategory § 464.20 Applicability; description of the copper casting subcategory....

  3. 49 CFR 192.373 - Service lines: Cast iron and ductile iron.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Service lines: Cast iron and ductile iron. 192.373... Regulators, and Service Lines § 192.373 Service lines: Cast iron and ductile iron. (a) Cast or ductile iron... cast iron pipe or ductile iron pipe is installed for use as a service line, the part of the...

  4. 75 FR 23295 - Iron Construction Castings From Brazil, Canada, and China

    Science.gov (United States)

    2010-05-03

    ... castings from Brazil, the antidumping duty order on ``heavy'' iron construction castings from Canada, and the antidumping duty orders on iron construction castings from Brazil and China. SUMMARY: The... ``heavy'' iron construction castings from Brazil, the antidumping duty order on ``heavy''...

  5. 75 FR 70900 - Certain Iron Construction Castings From Brazil, Canada, and the People's Republic of China...

    Science.gov (United States)

    2010-11-19

    ... International Trade Administration Certain Iron Construction Castings From Brazil, Canada, and the People's... certain iron construction castings (``castings'') from Brazil, Canada, and the People's Republic of China... were the orders to be revoked. See Certain Iron Construction Castings From Brazil, Canada, and...

  6. High-strength cast irons used for manufacturing parts of vaz passenger cars

    Science.gov (United States)

    Kitaigora, N. I.

    1996-10-01

    Methods for solving problems arising in the production of high-strength cast iron with stable properties and structure are considered. Results of introduction of new grades of high-strength cast iron instead of malleable cast iron and camshaft cast iron in the Volzhskii Automobile Plant are described.

  7. Cardiovascular cast model fabrication and casting effectiveness evaluation in fetus with severe congenital heart disease or normal heart.

    Science.gov (United States)

    Wang, Yu; Cao, Hai-yan; Xie, Ming-xing; He, Lin; Han, Wei; Hong, Liu; Peng, Yuan; Hu, Yun-fei; Song, Ben-cai; Wang, Jing; Wang, Bin; Deng, Cheng

    2016-04-01

    To investigate the application and effectiveness of vascular corrosion technique in preparing fetal cardiovascular cast models, 10 normal fetal heart specimens with other congenital disease (control group) and 18 specimens with severe congenital heart disease (case group) from induced abortions were enrolled in this study from March 2013 to June 2015 in our hospital. Cast models were prepared by injecting casting material into vascular lumen to demonstrate real geometries of fetal cardiovascular system. Casting effectiveness was analyzed in terms of local anatomic structures and different anatomical levels (including overall level, atrioventricular and great vascular system, left-sided and right-sided heart), as well as different trimesters of pregnancy. In our study, all specimens were successfully casted. Casting effectiveness analysis of local anatomic structures showed a mean score from 1.90±1.45 to 3.60±0.52, without significant differences between case and control groups in most local anatomic structures except left ventricle, which had a higher score in control group (P=0.027). Inter-group comparison of casting effectiveness in different anatomical levels showed no significant differences between the two groups. Intra-group comparison also revealed undifferentiated casting effectiveness between atrioventricular and great vascular system, or left-sided and right-sided heart in corresponding group. Third-trimester group had a significantly higher perfusion score in great vascular system than second-trimester group (P=0.046), while the other anatomical levels displayed no such difference. Vascular corrosion technique can be successfully used in fabrication of fetal cardiovascular cast model. It is also a reliable method to demonstrate three-dimensional anatomy of severe congenital heart disease and normal heart in fetus.

  8. STUDY ON MACRO AND MICRO MODELING ON SOLIDIFICATION PROCESS OF SHAPED CASTING

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Facing the market economy and global challenge the development of manufacturing industry especially casting industry is critical to the national economy. To reform the traditional casting industry by using computer technology is one of the hottest research frontiers studied by many researchers and engineers. Computer simulation of solidification process of shaped casting can assure the quality of casting, optimize the casting technology, shorten the lead time and therefore decrease the developing and manufacturing cost. Recently, numerical simulation of mold-filling and solidification processes of shaped casting and prediction of microstructure and property as well are extensively studied and put into application in many casting plants with many successful simulation cases.

  9. Tibia Shaft Fractures in Adolescents: How and When Can They be Managed Successfully With Cast Treatment?

    Science.gov (United States)

    Ho, Christine A

    2016-06-01

    Despite the increasing popularity of operative treatment in adolescent tibia fractures, casting remains a viable first-line treatment. Because the selection bias in published reports does not allow direct comparison between casting and flexible nail treatment of closed pediatric tibia fractures, it is unclear whether flexible nailing offers any advantages over casting. This overview discusses parameters of acceptable alignment, indications, techniques for successful reduction and casting, subsequent inpatient and outpatient management including wedging of casted tibia fractures, expected outcomes, and comparison of casting with flexible nailing. As with any orthopaedic procedure, careful attention to patient selection, indications, and detail facilitates successful cast treatment in this older pediatric population.

  10. High speed roll casting of Mg alloy strip by a vertical type twin roll caster

    OpenAIRE

    H.Watari; S. Kumai; Haga, T.

    2006-01-01

    Purpose: The possibility of high speed roll casting of AZ31, AM60 and AZ91 was investigated. Warm deep drawing of roll cast magnesium alloy was operated. and formability of roll cast magnesium strip was cleared.Design/methodology/approach: A vertical type high speed twin roll caster was used. The roll casting was operated in the air atmosphere. The casting speed was from 60 m/min up to 180 m/min. Low temperature casting was adopted to realize high speed casting.Findings: Strip thinner 3 mm wi...

  11. The effect of remelting on the melt and casting quality in Al–7%Si–Mg castings

    Energy Technology Data Exchange (ETDEWEB)

    Eisaabadi B, Ghasem [Department of Materials Science and Engineering, Sharif University of Technology, Tehran (Iran, Islamic Republic of); Foundry Technology Center, Korea Institute of Industrial Technology, Incheon (Korea, Republic of); Department of Materials Science and Engineering, Faculty of Engineering, Arak University, Arak (Iran, Islamic Republic of); Tiryakioğlu, Murat, E-mail: m.tiryakioglu@unf.edu [School of Engineering, University of North Florida Jacksonville, FL 32224 (United States); Davami, Parviz [Department of Materials Science and Engineering, Sharif University of Technology, Tehran (Iran, Islamic Republic of); Kim, Shae-Kwang; Yoon, Yong Ok; Yeom, Gil-Yong; Kim, Nam-Seok [Foundry Technology Center, Korea Institute of Industrial Technology, Incheon (Korea, Republic of)

    2014-05-01

    An experiment was conducted to determine whether allowing an aluminum melt to solidify in the crucible and later remelting it would improve the quality of the melt and the casting. To investigate this, data were collected through reduced pressure test, density measurement, metallography, X-ray radiography and tensile testing and analyzed statistically. Results indicated that remelting improved the quality of the melt by reduction of the number of defects in the casting and their area and volume fractions. The improvement in elongation of remelted specimens was found to be statistically significant. Analysis of deformation characteristics showed that the improvement in elongation is due to the improved casting quality after remelting.

  12. A comparative study of the centrifugal and vacuum-pressure techniques of casting removable partial denture frameworks.

    Science.gov (United States)

    Shanley, J J; Ancowitz, S J; Fenster, R K; Pelleu, G B

    1981-01-01

    A study was undertaken to evaluate two techniques for casting accuracy on removable partial denture frameworks: centrifugal casting and vacuum-pressure casting. A standard metal die with predetermined reference points in a horizontal plane was duplicated in refractory investment. The casts were waxed, and castings of nickel-chrome alloy were fabricated by the two techniques. Both the casts and the castings were measured between the reference points with a measuring microscope. With both casting methods, the differences between the casts and the castings were significant, but no significant differences were found between castings produced by the two techniques. Vertical measurements at three designated points also showed no significant differences between the castings. Our findings indicate that dental laboratories should be able to use the vacuum-pressure method of casting removable partial denture frameworks and achieve accuracy similar to that obtained by the centrifugal method of casting.

  13. Processing Technology and Mechanical Properties of Die-Cast Magnesium Alloy AZ91D

    Institute of Scientific and Technical Information of China (English)

    LIU Yan'gai(刘艳改); LIU Wenhui(刘文辉); XIONG Shoumei(熊守美); LIU Baicheng(柳百成); Wang Gang (王罡); MATSUMOTO Yoshihide; MURAKAMI Masayuki

    2004-01-01

    The mechanical properties of magnesium die-casting components can be improved with improved die-casting processing technology. An orthogonal experiment with four factors and three levels (Lq, 34) was used to evaluate the effect of various die-casting processing parameters on the quality and mechanical properties of an AZ91D magnesium alloy cylinder head cover component. The results show that the injection speed and casting and die temperatures all influence the component quality, with the influence of the casting pressure being the smallest. The injection speed and casting pressure are the two most important factors influencing the tensile strength. The best die-casting parameters for the magnesium alloy cylinder head cover component were determined to be a casting temperature of 660℃, a die temperature of 200℃, an injection speed of 70 ms(1, and a casting pressure of 65 MPa. The porosity is one of the most important parameters influencing the casting strength.

  14. Fused Cast Alumina Refractory Products for Glass Tank Furnace

    Institute of Scientific and Technical Information of China (English)

    SHEN Keyin

    2006-01-01

    @@ 1 Subject and Scope The standard specifies the requirement, testing method, inspection rule and requirements for the labeling, packing, shipping and storing of the fused cast alumina refractory products for glass tanks.

  15. A Methodology to Predict Uniform Material Fatigue Life of Cast Iron: Law for Cast Iron%A Methodology to Predict Uniform Material Fatigue Life of Cast Iron: Law for Cast Iron

    Institute of Scientific and Technical Information of China (English)

    Sinan Korkmaz

    2011-01-01

    Mechanical, physical and manufacturing properties of east iron make it attractive for many fields of application, such as cranks and cylinder holds. As in design of all metals, fatigue life prediction is an intrinsic part of the design process of structural sections that are made of cast iron. A methodology to predict high-cycle fatigue life of cast iron is proposed. Stress amplitude-strain amplitude, strain amplitude-number of loading cycles relationships of cast iron are investigated. Also, fatigue life prediction in terms of Smith, Watson and Topper parameter is carried out using the proposed method. Results indicate that the analytical outcomes of the proposed methodology are in good accordance with the experimental data for the two studied types of cast iron: EN-GJS-400 and EN-GJS-600.

  16. Numerical simulation for thermal flow filling process of casting

    Institute of Scientific and Technical Information of China (English)

    CHEN Ye; ZHAO Yu-hong; HOU Hua

    2006-01-01

    The solution algorithm (SOLA) method was used to solve the velocity and pressure field of the thermal flow filling process, and the volume of fluid (VOF) method for the free surface problem. Since the "donor-acceptor" rule often results in the free interface vague, the explicit difference method was adopted, and a method describing the free surface state at 0<F<1 was proposed to deal with this problem. In order to raise the computation efficiency, such algorithms were investigated and invalidated as: 1) internal and external area separation simplification algorithm; 2) the reducing necessary search area method. With the improved algorithms, the filling processes of the valve cover castings with gravity cast and an up cylinder block casting with low-pressure cast were simulated, the simulation results are believable and the computation efficiency is greatly improved. The SOLA-VOF model and its difference method for thermal fluid flow filling process were introduced.

  17. Development Program for Natural Aging Aluminum Casting Alloys

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Geoffrey K. Sigworth

    2004-05-14

    A number of 7xx aluminum casting alloys are based on the ternary Al-Zn-Mg system. These alloys age naturally to high strength at room temperature. A high temperature solution and aging treatment is not required. Consequently, these alloys have the potential to deliver properties nearly equivalent to conventional A356-T6 (Al-Si-Mg) castings, with a significant cost saving. An energy savings is also possible. In spite of these advantages, the 7xx casting alloys are seldom used, primarily because of their reputation for poor castibility. This paper describes the results obtained in a DOE-funded research study of these alloys, which is part of the DOE-OIT ''Cast Metals Industries of the Future'' Program. Suggestions for possible commercial use are also given.

  18. Alloying and Casting Furnace for Shape Memory Alloys Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The concept in the proposed project is to create a melting, alloying and casting furnace for the processing titanium based SMA using cold crucible techniques. The...

  19. An Energy Savings Model for the Heat Treatment of Castings

    Energy Technology Data Exchange (ETDEWEB)

    Y. Rong; R. Sisson; J. Morral; H. Brody

    2006-12-31

    An integrated system of software, databases, and design rules have been developed, verified, and to be marketed to enable quantitative prediction and optimization of the heat treatment of aluminum castings to increase quality, increase productivity, reduce heat treatment cycle times and reduce energy consumption. The software predicts the thermal cycle in critical locations of individual components in a furnace, the evolution of microstructure, and the attainment of properties in heat treatable aluminum alloy castings. The model takes into account the prior casting process and the specific composition of the component. The heat treatment simulation modules can be used in conjunction with software packages for simulation of the casting process. The system is built upon a quantitative understanding of the kinetics of microstructure evolution in complex multicomponent alloys, on a quantitative understanding of the interdependence of microstructure and properties, on validated kinetic and thermodynamic databases, and validated quantitative models.

  20. Excellent Casting Awards at the 2010 China International Foundry Expo

    Institute of Scientific and Technical Information of China (English)

    China Foundry Association

    2010-01-01

    @@ The curtain has fallen on the 2010 China International Foundry Expo(CIFEX),which was held in the new Beijing International Exhibition Centre on May 11-14,2010.This Expo had a total exhibition area of 100,000 ㎡ in eight halls,each one being fully occupied.Hall E1 was for domestic,large-sized Casting and Forging Products; Hall E2 was devoted to domestic Die Casting and Nonferrous Casting; Hall E3 housed the Provincial Pavilions and Foundry Industrial Clusters; Hall E4 exhibited domestic Foundry Materials; Hall W1 was the International Hall for Foundry,Metallurgical,Casting and Refractory exhibits;Hall W2 contained domestic Metallurgical Products; Hall W3 exhibited domestic Metallurgical,Industrial Furnace and Refractory products,and Hall W4 contained domestic Foundry Equipment.

  1. Wear resistant steels and casting alloys containing niobium carbide

    Energy Technology Data Exchange (ETDEWEB)

    Theisen, W.; Siebert, S.; Huth, S. [Lehrstuhl Werkstofftechnik, Ruhr-Univ. Bochum (Germany)

    2007-12-15

    Niobium, like titanium and vanadium, forms superhard MC carbides that remain relatively pure in technical alloys on account of their low solubility for other metallic alloying elements. However, because they have a greater hardness than the precipitated chromium carbides commonly used in wear-resistant alloys, they are suitable as alternative hard phases. This contribution deals with new wear-resistant steels and casting alloys containing niobium carbide. These include a secondary hardening hardfacing alloy, a composite casting alloy for wear applications at elevated temperatures, a white cast iron as well as two variants of a corrosion-resistant cold-work tool steel produced by melt metallurgy and by powder metallurgy. A heat-resistant casting alloy is also discussed. Based on equilibrium calculations the microstructures developing during production of the alloys are analysed, and the results are discussed with respect to important properties such as abrasive wear and corrosion resistance. (orig.)

  2. New trends in cold-chamber die casting machine design

    Institute of Scientific and Technical Information of China (English)

    R. Dańko; W. Kowalczyk

    2015-01-01

    Larger and larger proportions of aluminium castings, especial y those produced by the die casting process, can be observed during recent years in the automotive industry, house-hold articles and others. In case of the automotive industry, apart from the traditional elements produced by the die pressure method such as engine blocks or crank shaft bedplates, aluminium is displacing steel from structural parts of cars (‘body in white’). The current state and development directions of the structural solutions of cold-chamber die castings are analysed in this paper. These solutions drive the prospective development of these machines and die casting technology. The focus is mainly on essential functional systems such as:hydraulic drives of closing and locking units, as wel as pressing in die machines of known companies present on the European market.

  3. Eutectic solidification mode of spheroidal graphite cast iron and graphitization

    Institute of Scientific and Technical Information of China (English)

    Hideo Nakae; Sanghoon Jung; Takayuki Kitazawa

    2007-01-01

    The shrinkage and chilling tendency of spheroidal graphite (abbreviated SG) east iron is much greater than that of the flake graphite cast iron in spite of its higher amount of C and Si contents. Why? The main reason should be the difference in their graphitization during the eutectic solidification. In this paper, we discuss the difference in the solidification mechanism of both cast irons for solving these problems using unidirectional solidification and the cooling curves of the spheroidal graphite cast iron. The eutectic solidification rate of the SG cast iron is controlled by the diffusion of carbon through the austenite shell, and the final thickness is 1.4 times the radius of the SG, therefore, the reduction of the SG size, namely, the increase in the number, is the main solution of these problems.

  4. Managament quality of tools in the planned housing casting

    Directory of Open Access Journals (Sweden)

    Jaworski J.

    2007-01-01

    Full Text Available The Kaizen method of housing casting designing was presented in the paper. Algorithm making possibility of identification of tools limiting efficienty of tooling process was formulated. The system of tool management consisting of various was shown.

  5. Manufacturing technology of high-quality pressure castings

    Directory of Open Access Journals (Sweden)

    S. Pietrowski

    2011-10-01

    Full Text Available The paper presents manufacturing technology of pressure castings made of Al-Si alloy without porosity or with low microporosity of castings. It has been shown that the greatest impact on the porosity of the castings and the concentration of hydrogen has had the charge to the melting furnace. Liquidation or occurrence of a small microporosity of castings provides refining with solid refiners, nitrogen and modification of liquid alloy after various operations of preparing process. The liquid alloy stored in holding furnace should be refined once every 2 h with nitrogen. Authors developed a computer program of Al-Si alloys inspection with using of TDA method. The developed technology was verified under production conditions.

  6. Trials to manufacture and test castings from Inconel alloy

    Directory of Open Access Journals (Sweden)

    W. Uhl

    2010-07-01

    Full Text Available The article describes the methods of producing and testing the Inconel 740 nickel alloy in as-cast state. An assumption has been made that the obtained alloy should be characterised by a normative chemical composition and mechanical properties similar to those that are obtained in the process of plastic forming. The alloy was fabricated by conventional process and vacuum metallurgy in the form of pilot castings enabling various types of tests to be carried out. Within the test and investigations programme, moulding materials were chosen, castings were poured and subjected to the process of heat treatment, followed by tests and examinations of alloy properties (mechanical tests, cooling curves. The outcome of the investigations was cast alloy characterised by chemical composition close to the normative one but of the mechanical properties inferior to those obtained by plastic forming.

  7. The lost-foam casting of aluminum alloy components

    Science.gov (United States)

    Shivkumar, S.; Wang, L.; Apelian, D.

    1990-11-01

    In the lost-foam casting process, liquid metal is poured directly onto a refractory-coated, foamed polymer pattern which is buried in loose sand. The polymer pattern undergoes thermal degradation and is gradually replaced by the molten metal, which solidifies and produces the casting. The inherent operating advantages of this innovative technique have generated considerable interest among casting manufacturers. Currently, the process is being utilized to manufacture a wide variety of ferrous and nonferrous components catering primarily to the automotive industry. Because the process is relatively new, there is a compelling need to quantify the influence of process parameters on microstructure and mechanical properties. Furthermore, the interaction of the thermal degradation products with the solidifying metal may produce several unique defects in the casting.

  8. Production Scheduling for the Furnace - Casting Line System

    Directory of Open Access Journals (Sweden)

    A. Stawowy

    2013-07-01

    Full Text Available The problem considered in the paper is motivated by production planning in a foundry equipped with the furnace and casting line, which provides a variety of castings in various grades of cast iron/steel for a large number of customers. The quantity of molten metal does not exceed the capacity of the furnace, the load is a particular type of metal from which the products are made in the automatic casting lines. The goal is to create the order of the melted metal loads to prevent delays in delivery of goods to customers. This problem is generally considered as a lot-sizing and scheduling problem. The paper describes two computational intelligence algorithms for simultaneous grouping and scheduling tasks and presents the results achieved by these algorithms for example test problems.

  9. INCREASE OF EFFICIENCY OF MODIFIERS FOR GRAY CAST-IRON

    Directory of Open Access Journals (Sweden)

    O. S. Komarov

    2012-01-01

    Full Text Available It is established that for the purpose of increase of modifying efficiency of the melt from gray cast iron it is possible to use mechanically alloyed aluminum powder with superdispersed particles of aluminum and graphite oxide.

  10. New trends in cold-chamber die casting machine design

    Directory of Open Access Journals (Sweden)

    R. Dańko

    2015-07-01

    Full Text Available Larger and larger proportions of aluminium castings, especially those produced by the die casting process, can be observed during recent years in the automotive industry, house-hold articles and others. In case of the automotive industry, apart from the traditional elements produced by the die pressure method such as engine blocks or crank shaft bedplates, aluminium is displacing steel from structural parts of cars (‘body in white’. The current state and development directions of the structural solutions of cold-chamber die castings are analysed in this paper. These solutions drive the prospective development of these machines and die casting technology. The focus is mainly on essential functional systems such as: hydraulic drives of closing and locking units, as well as pressing in die machines of known companies present on the European market.

  11. DEVELOPMENT OF DIE-CASTING MOLDING PRODUCTION TECHNOLOGY

    Directory of Open Access Journals (Sweden)

    V. N. Kuzmich

    2012-01-01

    Full Text Available The main details of foundry equipment are developed. Analysis of the process of filling and hardening of casting “Transducer case” is carried out on the basis of methods of mathematic modeling of foundry processes.

  12. Abrasive wear behaviour of as cast and austempered ductile irons

    Energy Technology Data Exchange (ETDEWEB)

    Baydogan, M.; Koekden, M.U.; Cimenoglu, H. [Istanbul Technical Univ., Dept. of Metallurgy and Materials Science Engineering Istanbul (Turkey)

    2000-07-01

    In this study, abrasive wear behaviour of as cast and austempered GGG 50 and GGG 80 quality ductile irons was investigated. In the as cast condition, GGG 50 and GGG 80 quality ductile irons were having ferritic and pearlitic matrix structures, respectively. Austempering at 250 C after austenitisation at 900 C for 100 minutes produced bainitic matrix structure in both of the investigated ductile irons. Abrasive wear tests performed by rubbing the as cast and austempered specimens on Al{sub 2}O{sub 3} abrasive bands, revealed that austempering treatment improves abrasion resistance about 10-70% depending on the abrasive particle size and composition of the base iron. In the as cast condition, pearlitic GGG 80 grade ductile iron, has higher wear resistance than ferritic GGG 50 grade ductile iron. In the austempered condition GGG 50 and GGG 80 grade ductile irons which have bainitic matrix structure, exhibit almost similar wear resistance. (orig.)

  13. Possibilities of obtaining and controlling high-quality pressure castings

    Directory of Open Access Journals (Sweden)

    S. Pietrowski

    2011-07-01

    Full Text Available The paper presents the influence of the type of furnace charging melting, refining and modification silumins 226 and 231 on the porosity and microstructure of castings. It was shown that in order to reduce or eliminate the porosity of the castings is necessary to the refining ECOSAL-AL113 of liquid silumin both in the melting furnace, and in the ladle and an additional nitrogen, in the heat furnace modified and refining with nitrogen. To control the effects of refining and modifying the TDA method was used. It was found that based on crystal- lization curve can be qualitatively assess the gas porosity of the castings. In order to control and quality control silumins author developed a computer program using the method of TDA, which sets out: Rm, A5, HB and casting porosity P and the concentration of hydrogen in them. The program also informs the technological procedures to be performed for liquid silumin improper preparation.

  14. Awareness programs and change in taste-based caste prejudice.

    Science.gov (United States)

    Banerjee, Ritwik; Datta Gupta, Nabanita

    2015-01-01

    Becker's theory of taste-based discrimination predicts that relative employment of the discriminated social group will improve if there is a decrease in the level of prejudice for the marginally discriminating employer. In this paper we experimentally test this prediction offered by Garry Becker in his seminal work on taste based discrimination, in the context of caste in India, with management students (potential employers in the near future) as subjects. First, we measure caste prejudice and show that awareness through a TV social program reduces implicit prejudice against the lower caste and the reduction is sustained over time. Second, we find that the treatment reduces the prejudice levels of those in the left tail of the prejudice distribution--the group which can potentially affect real outcomes as predicted by the theory. And finally, a larger share of the treatment group subjects exhibit favorable opinion about reservation in jobs for the lower caste.

  15. Advanced lost foam casting technology. 1995 summary report

    Energy Technology Data Exchange (ETDEWEB)

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

    1996-05-01

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

  16. A Casting Yield Optimization Case Study: Forging Ram

    DEFF Research Database (Denmark)

    Kotas, Petr; Tutum, Cem Celal; Hattel, Jesper Henri;

    2010-01-01

    This work summarizes the findings of multi-objective optimization of a gravity sand-cast steel part for which an increase of the casting yield via riser optimization was considered. This was accomplished by coupling a casting simulation software package with an optimization module. The benefits...... of this approach, recently adopted in foundry industry world wide and based on fully automated computer optimization, were demonstrated. First, analyses of filling and solidification of the original casting design were conducted in the standard simulation environment to determine potential flaws and inadequacies....... Based on the initial assessment, the gating system was redesigned and the chills rearranged to improve the solidification pattern. After these two cases were evaluated, the adequate optimization targets and constraints were defined. One multi-objective optimization case with conflicting objectives...

  17. Inverse thermal analysis method to study solidification in cast iron

    DEFF Research Database (Denmark)

    Dioszegi, Atilla; Hattel, Jesper

    2004-01-01

    Solidification modelling of cast metals is widely used to predict final properties in cast components. Accurate models necessitate good knowledge of the solidification behaviour. The present study includes a re-examination of the Fourier thermal analysis method. This involves an inverse numerical...... solution of a 1-dimensional heat transfer problem connected to solidification of cast alloys. In the analysis, the relation between the thermal state and the fraction solid of the metal is evaluated by a numerical method. This method contains an iteration algorithm controlled by an under relaxation term...... was developed in order to investigate the thermal behaviour of the solidifying metal. Three cylindrically shaped cast samples surrounded by different cooling materials were introduced in the same mould allowing a common metallurgical background for samples solidifying at different cooling rates. The proposed...

  18. EFFICIENCY CHARACTERISTICS OF MICROALLOYED AND MODIFIED WHITE CAST IRONS

    Directory of Open Access Journals (Sweden)

    M. M. Jamshinskiy

    2013-01-01

    Full Text Available Influencing of chrome and manganese in the wide range of their concentrations on wear proof of white cast-irons for making of the poured details working in the conditions of intensive abrasive and hydroabrasive wear is studied. It is set that at optimum correlation of these elements cast-irons have high hardness, wearproof and satisfactory casting properties, allowing to make the poured details of different mass, geometry and overall sizes. Influence of processes of микролегирования and modification is explored on operating properties of the recommended Cr-Mn cast-iron 290Х19Г4 and expedience of the use of these processes is set at production of the wearproof foundings taking into account concrete external environments.

  19. Analysis of nucleation modelling in ductile cast iron

    DEFF Research Database (Denmark)

    Moumeni, Elham; Tutum, Cem Celal; Tiedje, Niels Skat;

    2012-01-01

    Heterogeneous nucleation of nodular graphite at inclusions in ductile iron during eutectic solidification has been investigated. The experimental part of this work deals with casting of ductile iron samples with two different inoculants in four different thicknesses. Chemical analysis...

  20. Thin-slab casting – New possibilities

    Indian Academy of Sciences (India)

    Amit Chatterjee; Sanjay Chandra

    2001-02-01

    Changes in the IT industry are known to proceed at a scorching pace. In sharp contrast, the rate of development in the steel industry is generally slow. Nonetheless, The impact of recent technical developments on the steel industry has been quite significant. The production chain from iron ore to final rolled steel is a long one and the shortening of this length has long been the endeavour of scientists and engineers. The initial development came in the form of speeding up the process of steelmaking by reducing the slow open-hearth process (8 h tap-to-tap time) with the 45 min tap-tp-tap time of the Basic Oxygen Furnace (BOF) process. Significant developments thereafter have been in the process of continuous production of billets and blooms from liquid steel thereby doing away with the large blooming mills needed for rolling ingots. For a fairly long time after the stabilisation of continuous casting. hot rolling involved reheating thick (200-250 mm) slabs and reducing them in a hot-strip mill. The advent of thin-slab casters has made even these large hot-strip mills redundant. The new installtion produce thin slabs (50-70 mm) that are directly rolled into strips without the need of an intermediate furnace for raising the stock temperature; the so-called tunnel furance prior to the rolling stands serving only to equalise stock temperatures. Additionally, what started as a step for reducing investment in hot rolling has, in fact, given new opportunity for direct hot rolling of thickness that were, for long, considered to be feasible only through the cold-rolling route. This article discuss the slow but steady encroachment of hot-rolled sheets into the domain of strip thickness hitherto produced by cold rolling and tries to show how the development of thin-slab casters has allowed this process to be accelerated. A techno-economic analysis of thin-slab casting has been presented along with the benefits that arise when a thin-slab caster is linked to the blast furnace

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2005-09-30

    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

  2. Ductile cast iron obtaining by Inmold method with use of LOST FOAM process

    Directory of Open Access Journals (Sweden)

    T. Pacyniak

    2010-01-01

    Full Text Available The possibility of manufacturing of ductile cast iron castings by Inmold method with use of LOST FOAM process was presented in this work. The spheroidization was carried out by magnesium master alloy in amounts of 1% casting mass. Nodulizer was located in the reactive chamber in the gating system made of foamed polystyrene. Pretests showed, that there are technical possibilities of manufacturing of casts from ductile cast iron in the LOST FOAM process with use of spheroidization in mould.

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

    Science.gov (United States)

    Frankhouser, W. L.

    1980-01-01

    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.

  4. Ductile cast iron obtaining by Inmold method with use of LOST FOAM process

    OpenAIRE

    T. Pacyniak; R. Kaczorowski

    2010-01-01

    The possibility of manufacturing of ductile cast iron castings by Inmold method with use of LOST FOAM process was presented in this work. The spheroidization was carried out by magnesium master alloy in amounts of 1% casting mass. Nodulizer was located in the reactive chamber in the gating system made of foamed polystyrene. Pretests showed, that there are technical possibilities of manufacturing of casts from ductile cast iron in the LOST FOAM process with use of spheroidization in mould.

  5. Social interactions affecting caste development through physiological actions in termites.

    Science.gov (United States)

    Watanabe, Dai; Gotoh, Hiroki; Miura, Toru; Maekawa, Kiyoto

    2014-01-01

    A colony of social insects is not only an aggregation of individuals but also a functional unit. To achieve adaptive social behavior in fluctuating environmental conditions, in addition to coordination of physiological status in each individual, the whole colony is coordinated by interactions among colony members. The study on the regulation of social-insect colonies is termed "social physiology." Termites, a major group of social insects, exhibit many interesting phenomena related to social physiology, such as mechanisms of caste regulation in a colony. In their colonies, there are different types of individuals, i.e., castes, which show distinctive phenotypes specialized in specific colony tasks. Termite castes comprise reproductives, soldiers and workers, and the caste composition can be altered depending on circumstances. For the regulation of caste compositions, interactions among individuals, i.e., social interactions, are thought to be important. In this article, we review previous studies on the adaptive meanings and those on the proximate mechanisms of the caste regulation in termites, and try to understand those comprehensively in terms of social physiology. Firstly, we summarize classical studies on the social interactions. Secondly, previous studies on the pheromone substances that mediate the caste regulatory mechanisms are overviewed. Then, we discuss the roles of a physiological factor, juvenile hormone (JH) in the regulation of caste differentiation. Finally, we introduce the achievements of molecular studies on the animal sociality (i.e., sociogenomics) in terms of social physiology. By comparing the proximate mechanisms of social physiology in termites with those in hymenopterans, we try to get insights into the general principles of social physiology in social animals.

  6. Cast Metal Coalition Research and Development Closeout Report

    Energy Technology Data Exchange (ETDEWEB)

    Allen, D.

    2000-08-01

    The Cast Metal Coalition, composed of more than 22 research providers and universities and 149 industrial partners, has completed a four-year research and development partnership with the Department of Energy. This report provides brief summaries of the 29 projects performed by the Coalition. These projects generated valuable information in such aspects of the metals industry as process prediction technologies, quality control, improved alloys, product machinability, and casting process improvements.

  7. Wear Property of Cast Steel Wheel Material in Rail Truck

    Institute of Scientific and Technical Information of China (English)

    MI Guo-fa; LIU Yan-lei; ZHANG Bin; FU Xiu-qin; ZHANG Hong; SONG Guo-xiang

    2009-01-01

    Wear property of material plays a key role in the service time of workpiece.A major objective in the development of new wheel materials is to improve the wear performance.The wear property of B and B+ grade cast steel materials was reported.The results showed that B+ grade cast steel material exhibited better wear property than the B grade material.Carbon content related to the hardness match was the principal factor affecting the wear properties.

  8. Microstructures and properties of aluminum die casting alloys

    Energy Technology Data Exchange (ETDEWEB)

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

    1998-10-01

    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.

  9. Stereology of carbide phase in modified hypereutectic chromium cast iron

    Directory of Open Access Journals (Sweden)

    J. Suchoń

    2010-04-01

    Full Text Available In paper are presented results of studies of carbide phase stereology modified hypereutectic wear resistance chromium cast iron which contains carbon about 3,5% and chromium about 25%. Three substances were applied to the modification: boron carbide (B4C, ferroniobium (FeNb and mixture of ferroniobium and rare-earth (RE. The measurements of geometrical features of carbides were conducted on microsection taken from castings wich were cooled with various velocities.

  10. Die Casting Mold Design for Aluminum Alloy Shell of Instrument

    Directory of Open Access Journals (Sweden)

    Li Yuanyuan

    2015-01-01

    Full Text Available This paper is about die casting mold design for aluminum alloy shell of instrument. Three-dimensional model of the casting and mold are designed by using Pro/Engineer and AutoCad which can analyze forming quality. Digital design and theoretical calculation can greatly shorten product development cycle and mold design cycle, improve the accuracy of product design and mold design, and reduce the cost of mold design.

  11. Extended Leach Testing of Simulated LAW Cast Stone Monoliths

    Energy Technology Data Exchange (ETDEWEB)

    Serne, R. Jeffrey [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Westsik, Joseph H. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Williams, Benjamin D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Jung, H. B. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Wang, Guohui [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-07-09

    This report describes the results from long-term laboratory leach tests performed at Pacific Northwest National Laboratory (PNNL) for Washington River Protection Solutions (WRPS) to evaluate the release of key constituents from monoliths of Cast Stone prepared with four simulated low-activity waste (LAW) liquid waste streams. Specific objectives of the Cast Stone long-term leach tests described in this report focused on four activities: 1. Extending the leaching times for selected ongoing EPA-1315 tests on monoliths made with LAW simulants beyond the conventional 63-day time period up to 609 days reported herein (with some tests continuing that will be documented later) in an effort to evaluate long-term leaching properties of Cast Stone to support future performance assessment activities. 2. Starting new EPA-1315 leach tests on archived Cast Stone monoliths made with four LAW simulants using two leachants (deionized water [DIW] and simulated Hanford Integrated Disposal Facility (IDF) Site vadose zone pore water [VZP]). 3. Evaluating the impacts of varying the iodide loading (starting iodide concentrations) in one LAW simulant (7.8 M Na Hanford Tank Waste Operations Simulator (HTWOS) Average) by manufacturing new Cast Stone monoliths and repeating the EPA-1315 leach tests using DIW and the VZP leachants. 4. Evaluating the impacts of using a non-pertechnetate form of Tc that is present in some Hanford tanks. In this activity one LAW simulant (7.8 M Na HTWOS Average) was spiked with a Tc(I)-tricarbonyl gluconate species and then solidified into Cast Stone monoliths. Cured monoliths were leached using the EPA-1315 leach protocol with DIW and VZP. The leach results for the Tc-Gluconate Cast Stone monoliths were compared to Cast Stone monoliths pertechnetate.

  12. Effects of finishing on the surface quality of precision castings

    Directory of Open Access Journals (Sweden)

    Patejuk A.

    2007-01-01

    Full Text Available The paper presents some manufacturing problems concerning leaded brass casting using the precision casting method. It shows that the quality of the alloy depends on the intermetalic phase compounds known as hard inclusions that are formed in the alloy. The intrusions, composed mainly of iron, have also negative influence on obtaining good quality i.e. smooth surfaces of products. One of the methods to improve surface smoothness proposed by authors is to apply additional copper plating and fine polishing.

  13. Characterization of CAST Poly-Si using DLTS Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, I.G. [Electronics Telecommunications Research Institute (Korea, Republic of)

    1994-09-01

    In this experiments DLTS measurements were used to characterize the cast poly-Si. Peaks from the DLTS measurements show the defect levels and defect concentrations. Carbon peak with 0.35 eV above the valence band and other continuous peaks were found in cast poly-Si. Measured DLTS peaks are modeled using energy distribution and good agreements between the experiments and the modeling were achieved. (author). 8 refs., 10 figs.

  14. Successful Asia-Pacific Die Casting Industry Exhibition'2005

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    @@ Upon the expectation of practitioners in the die casting industry, the Asia-Pacific Die Casting Industry Exhibition'2005, sponsored by Chinese Mechanical Engineering Society (CMES) and China Productivity Promotion Center of Machinery Industry, organized by Foundry Institution of Chinese Mechanical Engineering Society (FICMES) and Productivity Promotion Center of Foundry Industry of China, was successfully held in INTEX Shanghai, China on August 13-17,2005.

  15. A new method of producing casts for anatomical studies.

    Science.gov (United States)

    De Sordi, Nadia; Bombardi, Cristiano; Chiocchetti, Roberto; Clavenzani, Paolo; Trerè, Claudio; Canova, Marco; Grandis, Annamaria

    2014-09-01

    The objective of the present study was to verify if polyurethane foam is a suitable material to make accurate casts of vessels and viscera, and to develop a method based on its use for anatomical studies. This new technique has been tested primarily on the lungs of different animals, but also on the renal, intestinal and equine digital vessels. It consisted of three steps: specimen preparation, injection of the foam and corrosion of the cast. All structures injected with foam were properly filled. The bronchial tree and the vessels could be observed up to their finer branches. The method is inexpensive, simple and requires no special equipment. The pre-casting procedure does not require perfusion of the specimens with formalin, or prolonged flushing with carbon dioxide gas or air for drying. The polyurethane foam does not need a catalyst. It is simply diluted with acetone, which does not cause shrinkage of the cast due to evaporation during hardening. The foam naturally expands into the cavities without high pressure of the inoculum, and hardens in just 2 or 3 h at room temperature. Only two drawbacks were observed. The first is the fact that multiple injections cannot be made in the same cavity since the foam solidifies quickly; the second is the slight brittleness of the cast, due to the low elasticity of polyurethane foam. In conclusion, polyurethane foam was a suitable material for producing accurate casts of vessels and viscera.

  16. Geometrical precision of 3DP casting form for founding gears

    Directory of Open Access Journals (Sweden)

    T. Markowski

    2010-01-01

    Full Text Available The article presents analysis of geometrical precision of casting form made by means of 3DP method. Three dimentional printing is a universal method of rapid prototyping which can be used to make tools – castings forms as a Rapid Tooling method. By means of this method in direct incremental process a casting form of spur gear was created. Precision of creating the form by 3DP method depends on different factors. Technological factors depending on machine operator include: the thickness of the layer and placing the model in working space. The precision of creating the model also depends on preparing the printer for work: the condition and calibration of printing heads, the condition of the printing unit slide guides and preparing the working space. Three dimentional printer Z510 Spectrum was prepared for work in a way assuring the greatest precision of created models. Technological parameters responsible for precision were set on maximum values. The aim of the research was defining the precision of casting form generated by 3DP Rapid Prototyping Method. The research was made by means of coordinate measuring machine Wenzel LH87. The measuring machine software was used to compare the outcome of the measurement to nominal model 3D-CAD. The problem of tool precision of casting forms generated by Rapid Tooling is rarely considered in literature covering rapid prototyping and casting technologies. That is why the research presented in this article isan original work in the technological and practical aspect.

  17. Development of Cast Alumina-Forming Austenitic Stainless Steels

    Science.gov (United States)

    Muralidharan, G.; Yamamoto, Y.; Brady, M. P.; Walker, L. R.; Meyer, H. M., III; Leonard, D. N.

    2016-09-01

    Cast Fe-Ni-Cr chromia-forming austenitic stainless steels with Ni levels up to 45 wt.% are used at high temperatures in a wide range of industrial applications that demand microstructural stability, corrosion resistance, and creep strength. Although alumina scales offer better corrosion protection at these temperatures, designing cast austenitic alloys that form a stable alumina scale and achieve creep strength comparable to existing cast chromia-forming alloys is challenging. This work outlines the development of cast Fe-Ni-Cr-Al austenitic stainless steels containing about 25 wt.% Ni with good creep strength and the ability to form a protective alumina scale for use at temperatures up to 800-850°C in H2O-, S-, and C-containing environments. Creep properties of the best alloy were comparable to that of HK-type cast chromia-forming alloys along with improved oxidation resistance typical of alumina-forming alloys. Challenges in the design of cast alloys and a potential path to increasing the temperature capability are discussed.

  18. Numerical Simulation and Cold Modeling experiments on Centrifugal Casting

    Science.gov (United States)

    Keerthiprasad, Kestur Sadashivaiah; Murali, Mysore Seetharam; Mukunda, Pudukottah Gopaliengar; Majumdar, Sekhar

    2011-02-01

    In a centrifugal casting process, the fluid flow eventually determines the quality and characteristics of the final product. It is difficult to study the fluid behavior here because of the opaque nature of melt and mold. In the current investigation, numerical simulations of the flow field and visualization experiments on cold models have been carried out for a centrifugal casting system using horizontal molds and fluids of different viscosities to study the effect of different process variables on the flow pattern. The effects of the thickness of the cylindrical fluid annulus formed inside the mold and the effects of fluid viscosity, diameter, and rotational speed of the mold on the hollow fluid cylinder formation process have been investigated. The numerical simulation results are compared with corresponding data obtained from the cold modeling experiments. The influence of rotational speed in a real-life centrifugal casting system has also been studied using an aluminum-silicon alloy. Cylinders of different thicknesses are cast at different rotational speeds, and the flow patterns observed visually in the actual castings are found to be similar to those recorded in the corresponding cold modeling experiments. Reasonable agreement is observed between the results of numerical simulation and the results of cold modeling experiments with different fluids. The visualization study on the hollow cylinders produced in an actual centrifugal casting process also confirm the conclusions arrived at from the cold modeling experiments and numerical simulation in a qualitative sense.

  19. Development of Cast Alumina-Forming Austenitic Stainless Steels

    Science.gov (United States)

    Muralidharan, G.; Yamamoto, Y.; Brady, M. P.; Walker, L. R.; Meyer, H. M., III; Leonard, D. N.

    2016-11-01

    Cast Fe-Ni-Cr chromia-forming austenitic stainless steels with Ni levels up to 45 wt.% are used at high temperatures in a wide range of industrial applications that demand microstructural stability, corrosion resistance, and creep strength. Although alumina scales offer better corrosion protection at these temperatures, designing cast austenitic alloys that form a stable alumina scale and achieve creep strength comparable to existing cast chromia-forming alloys is challenging. This work outlines the development of cast Fe-Ni-Cr-Al austenitic stainless steels containing about 25 wt.% Ni with good creep strength and the ability to form a protective alumina scale for use at temperatures up to 800-850°C in H2O-, S-, and C-containing environments. Creep properties of the best alloy were comparable to that of HK-type cast chromia-forming alloys along with improved oxidation resistance typical of alumina-forming alloys. Challenges in the design of cast alloys and a potential path to increasing the temperature capability are discussed.

  20. Application of 3D stereoscopic visualization technology in casting aspect

    Institute of Scientific and Technical Information of China (English)

    Kang Jinwu; Zhang Xiaopeng; Zhang Chi; Liu Baicheng

    2014-01-01

    3D stereoscopic visualization technology is coming into more and more common use in the field of entertainment, and this technology is also beginning to cut a striking ifgure in casting industry and scientiifc research. The history, fundamental principle, and devices of 3D stereoscopic visualization technology are reviewed in this paper. The authors’ research achievements on the 3D stereoscopic visualization technology in the modeling and simulation of the casting process are presented. This technology can be used for the observation of complex 3D solid models of castings and the simulated results of solidiifcation processes such as temperature, lfuid lfow, displacement, stress strain and microstructure, as wel as the predicted defects such as shrinkage/porosity, cracks, and deformation. It can also be used for other areas relating to 3D models, such as assembling of dies, cores, etc. Several cases are given to compare the illustration of simulated results by traditional images and red-blue 3D stereoscopic images. The spatial shape is observed better by the new method. The prospect of 3D stereoscopic visualization in the casting aspect is discussed as wel. The need for aided-viewing devices is stil the most prominent problem of 3D stereoscopic visualization technology. However, 3D stereoscopic visualization represents the tendency of visualization technology in the future; and as the problem is solved in the years ahead, great breakthroughs wil certainly be made for its application in casting design and modeling and simulation of the casting processes.

  1. Effect of inoculating addition on machinability of gray cast iron

    Institute of Scientific and Technical Information of China (English)

    REN Fengzhang; LI Fengjun; LIU Weiming; MA Zhanhong; TIAN Baohong

    2009-01-01

    Gray cast irons were inoculated with FeSi75+RE and FeSi75+Sr inoculants. The changes of apex angle of the drills before and af-ter being used were used to evaluate machinability of gray cast irons. Effect of FeSi75+RE and FeSi75+Sr inoculants on mechanical proper-ties, machinability and sensibility of gray cast iron used in cylinder block were investigated. Experimental results showed that gray cast iron treated with 60%FeSi75+40% RE inoculants exhibited tensile strength consistently at about 295 MPa along with good hardness and im-proved metallurgical quality. While gray cast iron inoculated with 20%FeSi75+80% Sr inoculants exhibited the best machinability, the low-est cross-section sensibility and the least microhardness difference. The tool flank wear of the drill increased correspondingly with the in-crease of the microhardness difference of the matrix, indicating the great effect of homogeneity of the matrix on the machinability of gray cast iron.

  2. Modelling of Filling, Microstructure Formation, Local Mechanical Properties and Stress – Strain Development in High-Pressure Die Cast Aluminium Castings

    DEFF Research Database (Denmark)

    Kotas, Petr; Hattel, Jesper Henri; Thorborg, Jesper

    2009-01-01

    inherently affects the component’s properties depending on design, metallurgy and casting technique. The wall thickness influences the coarseness of the microstructure and the material will have properties depending on the local metallurgical and thermal histories. This is independent on the material, i.......e. whether the casting is based on cast iron- or aluminium-alloys. The distribution of local properties in a casting might vary substantially which makes it complex to optimize the casting with good accuracy. Often, mechanical simulations of the load situation are based on the assumption that the cast...... product has constant material properties throughout the entire casting. Thus, if the microstructure is determined or predicted at a given point, it gives the possibility to calculate the local material behavior more realistically. In the present work, a test case of a complex high-pressure die cast part...

  3. Physical, nutrients, biological, meteorological, and other data from bottle casts, CTD casts, and divers, from FIXED PLATFORMS from 06 February 1989 to 12 March 1998 (NODC Accession 9800185)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Physical, chemical, biological, meteorological, and other data were collected from bottle casts, CTD casts, and divers from FIXED PLATFORMS. Data were collected by...

  4. Evaluation of producing technique factors affecting the matrix microstructure of as-cast ductile iron castings

    Directory of Open Access Journals (Sweden)

    S. Bockus

    2011-01-01

    Full Text Available The objective of this paper was to investigate some important parameters related to ductile iron matrix microstructure. Ductile iron round bars of various diameters in order to achieve various cooling rates were obtained in different conditions. None heat treatment was used to obtain different pearlite contents in the microstructures. The correlation between kind of inoculants, specimens size, carbon equivalent, and matrix microstructure was investigated. The results demonstrated that the slow cooling rate, inoculants with rare earth elements, and relatively little residual magnesium content decreased the pearlite content. This study is of great importance for the development of new economical methods for production of ductile iron castings.

  5. Optimization of casting defects analysis with supply chain in cast iron foundry process

    Directory of Open Access Journals (Sweden)

    C. Narayanaswamy

    2016-10-01

    Full Text Available Some of the foundries are in need of meeting production targets and due to the urgency they ignore the rejections. The objective of this paper is to analyze the various defects, [1] from molding process in a cast iron foundry. The Failure Mode Effects Analysis (FMEA in quality control [2-6] with suitable supply chain for mold making process considering rejection rates are identified and analyzed in terms of Risk Priority Number (RPN to prioritize the attention for each of the problem. The optimum levels of selected parameters [7] are obtained in this analysis.

  6. Determination of Bulk Dimensional Variation in Castings

    Energy Technology Data Exchange (ETDEWEB)

    Dr. James F. Cuttino Dr. Edward P. Morse

    2005-04-14

    The purpose of this work is to improve the efficiency of green sand foundries so that they may continue to compete as the most cost-effective method of fabrication while meeting tightening constraints on near-net shape manufacturing. In order to achieve this objective, the study is divided into two major components. The first component concentrated on identifying which processes control surface finish on the castings and which provide potential reductions in variations. The second component identified metrological methods that effectively discern between the geometry of bulk material versus surface finish in order to more accurately determine the quality of a part. The research resulted in the determination of an empirical relationship relating pouring parameters to dimensional variation, with an R2 value of greater than 0.79. A significant difference in variations obtained from vertical vs. horizontal molding machines was also noticed. When analyzed separately, however, the resulting empirical relationships for horizontal and vertical machines had reduced R2 values, probably due to the reduced data sets. Significant parameters when considering vertical and horizontal molding machines together included surface roughness, pattern type, iron type, pouring rate, copper content, amount of Western Bentonite, and permeability.

  7. The degradation processes in high loaded casts

    Directory of Open Access Journals (Sweden)

    E. Ďuriníková

    2010-01-01

    Full Text Available In this work are described structural changes of jet engine DV – 2 turbine blades and effect of degradation process. Turbine blades work in aggressively environs and because of that there are rate among high loaded cast stock. As an experimental material we have chose nickel superalloy ŽS6K with surface heat - resisting alitize layer. Evaluation is slant on largeness wearing over work of certain number of hour in operation. Effect working environs and overrun working temperatures is show changes measures as well as changes macrostructure of basic material blades. Evaluate is advance quantitative metallography through the medium metallographic software NIS element. Quantitative analysis evaluate thickness measures, quality control outer look and lack mixture in the seat, which is not splash, is precede by lack of near another applied protective layer. Allowance is knot on last examination in the area ratings protective heat-resisting layers and gives records for others possible ratings and experiments in this area.

  8. Heat Treatment Procedure Qualification for Steel Castings

    Energy Technology Data Exchange (ETDEWEB)

    Mariol Charles; Nicholas Deskevich; Vipin Varkey; Robert Voigt; Angela Wollenburg

    2004-04-29

    Heat treatment practices used by steel foundries have been carefully studied as part of comprehensive heat treatment procedure qualification development trials. These studies highlight the relationships between critical heat treatment process control parameters and heat treatment success. Foundry heat treatment trials to develop heat treatment procedure qualifications have shed light on the relationship between heat treatment theory and current practices. Furnace load time-temperature profiles in steel foundries exhibit significant differences depending on heat treatment equipment, furnace loading practice, and furnace maintenance. Time-temperature profiles of furnace control thermocouples can be very different from the time-temperature profiles observed at the center of casting loads in the furnace. Typical austenitization temperatures and holding times used by steel foundries far exceed what is required for transformation to austenite. Quenching and hardenability concepts were also investigated. Heat treatment procedure qualification (HTPQ) schema to demonstrate heat treatment success and to pre-qualify other alloys and section sizes requiring lesser hardenability have been developed. Tempering success is dependent on both tempering time and temperature. As such, furnace temperature uniformity and control of furnace loading during tempering is critical to obtain the desired mechanical properties. The ramp-up time in the furnace prior to the establishment of steady state heat treatment conditions contributes to the extent of heat treatment performed. This influence of ramp-up to temperature during tempering has been quantified.

  9. As-cast structure of DC casting 7075 aluminum alloy obtained under dual-frequency electromagnetic field

    Institute of Scientific and Technical Information of China (English)

    Zhi-hao Zhao; Zhen Xu; Gao-song Wang; Qing-feng Zhu; Jian-zhong Cui

    2014-01-01

    We have experimentally determined the as-cast structures of semi-continuous casting 7075 aluminum alloy obtained in the pres-ence of dual-frequency electromagnetic field. Results suggest that the use of dual-frequency electromagnetic field during the semi-continuous casting process of 7075 aluminum alloy ingots reduces the thickness of the surface segregation layer, increases the height of the melt menis-cus, enhances the surface quality of the ingot, and changes the surface morphology of the melt pool. Moreover, low-frequency electromag-netic field was found to show the most obvious influence on improving the as-cast structure because of its high permeability in conductors.

  10. LATE MODIFYING IS AN EFFECTIVE WAY OF THE CAST IRON CRYSTALLIZATION CONTROL AT PRODUCTION OF THIN-WALLED CASTING

    Directory of Open Access Journals (Sweden)

    S. P. Korolev

    2006-01-01

    Full Text Available It is shown that application of special modifiers allowed to carry out effective late graphitizing modification, which provided elimination of border chill in thin castings of complex configuration in terms of mass production.

  11. Letter Report: LAW Simulant Development for Cast Stone Screening Test

    Energy Technology Data Exchange (ETDEWEB)

    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

    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

  12. Soldier caste influences on candidate primer pheromone levels and juvenile hormone-dependent caste differentiation in workers of the termite Reticulitermes flavipes

    Science.gov (United States)

    Caste systems and the division of labor they make possible are common underlying features of all social insects. Multiple extrinsic factors have been shown to impact caste differentiation; for example, primer pheromones are chemical signaling molecules produced by certain castes that impact developm...

  13. Simulation of continuous cast steel product solidification

    Directory of Open Access Journals (Sweden)

    Ardelean, E.

    2007-06-01

    Full Text Available Primary cooling – inside the tundish – has a great impact over the thickness of the solidified steel crust. If on exiting the tundish the crust is too thin, it can punch and break, as a result of the ferrostatic pressure exerted from the inside by the liquid steel as well as because of the weight of the molten steel. The parameters that influence the amount of dissipated heat depend on the cooling water flow of the tundish, on the pressure and temperature of the cooling water but also on the overheating of the continuously cast steel. The secondary cooling takes place at the exit of the semi-finished product from the tundish, when the solidification is supposed to take place all along the cross section of the strand. In order to achieve it, in addition to a correctly managed primary cooling, it is necessary to obtain the proper correlation of the factors that influence the secondary cooling as well: the water flow rate long the three zones of the installation and its pressure in the secondary circuit. All these have in view a proper solidification length; an intense cooling can generate cracks due to the thermal stress, while a too slow cooling can generate a partial solidification of the strand up to the cropping machine area. The paper presents a mathematical simulation of the continuously cast steel solidification.

    El enfriamiento primario del cristalizador tiene una gran importancia sobre el espesor de la costra de acero solidificado. Si al salir del cristalizador, esta costra es demasiado sutil, bajo la acción de la presión ferro estática ejercitada por el acero líquido del interior y gracias el peso propio del hilo, ésta, puede perforar resultando su rompimiento. Los parámetros que influenyen sobre la cantidad de calor cedida dependen del agua de enfriamiento del catalizador, de la presión y de la temperatura de agua de enfriamiento, pero también del sobrecalentamiento del acero fundido continuamente. A la salida del

  14. Secondary Waste Cast Stone Waste Form Qualification Testing Plan

    Energy Technology Data Exchange (ETDEWEB)

    Westsik, Joseph H.; Serne, R. Jeffrey

    2012-09-26

    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

  15. Yield improvement and defect reduction in steel casting

    Energy Technology Data Exchange (ETDEWEB)

    Kent Carlson

    2004-03-16

    This research project investigated yield improvement and defect reduction techniques in steel casting. Research and technology development was performed in the following three specific areas: (1) Feeding rules for high alloy steel castings; (2) Unconventional yield improvement and defect reduction techniques--(a) Riser pressurization; and (b) Filling with a tilting mold; and (3) Modeling of reoxidation inclusions during filling of steel castings. During the preparation of the proposal for this project, these areas were identified by the High Alloy Committee and Carbon and Low Alloy Committee of the Steel Founders' Society of America (SFSA) as having the highest research priority to the steel foundry industry. The research in each of the areas involved a combination of foundry experiments, modeling and simulation. Numerous SFSA member steel foundries participated in the project through casting trials and meetings. The technology resulting from this project will result in decreased scrap and rework, casting yield improvement, and higher quality steel castings produced with less iteration. This will result in considerable business benefits to steel foundries, primarily due to reduced energy and labor costs, increased capacity and productivity, reduced lead-time, and wider use and application of steel castings. As estimated using energy data provided by the DOE, the technology produced as a result of this project will result in an energy savings of 2.6 x 10{sup 12} BTU/year. This excludes the savings that were anticipated from the mold tilting research. In addition to the energy savings, and corresponding financial savings this implies, there are substantial environmental benefits as well. The results from each of the research areas listed above are summarized.

  16. Solidification process and infrared image characteristics of permanent mold castings

    Science.gov (United States)

    Viets, Roman; Breuer, Markus; Haferkamp, Heinz; Kruessel, Thomas; Niemeyer, Matthias

    1999-03-01

    Interdependence between the development of temperature gradients at the solid-liquid interface during solidification of metals and the formation of local defects demands for thermal investigation. In foundry practice thermocouples are used to control the die's overall cooling-rate, but fluctuations in product quality still occur. Capturing FIR- thermograms after opening the die visualizes the state, when most thermal throughput has already flattened the temperature gradients in the mold. Rapid dissipation of heat from liquid metal to the mold during solidification forces further approach of the process investigation by slowing down the heat flux or the use of transparent mold material. Aluminum gravity casting experiments under technical vacuum conditions lead to decelerated solidification by suppression of convection and image sequences containing explicit characteristics that could be assigned to local shrinkage of the casting. Hence relevant clusters are extracted and thermal profiles are drawn from image series, pointing out correlations between feeding performance from the sink heads and the appearance of local defects. Tracing thermal processes in vacuum casting can scarcely be transferred to image data in foundry practice, since only little analogies exist between atmospheric and vacuum casting. The diagnosis of the casting process requires detection of the still closed mold using a transparent silica- aerogel sheet as part of the die. Hereby thermograms of the initial heat input are recorded by adapting a NIR-camera in addition to the FIR-unit. Thus the entire thermal compensation at the joint face for each casting is visualized. This experimental set-up is used for image sequence analysis related to the intermediate casting phases of mold filling, body formation and solidification shrinkage.

  17. Application of particle method to the casting process simulation

    Science.gov (United States)

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

    2012-07-01

    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.

  18. High speed twin roll caste for aluminum alloy thin strip

    Directory of Open Access Journals (Sweden)

    T. Haga

    2007-09-01

    Full Text Available Purpose: In the present study, effectiveness of a high-speed twin roll caster for recycling aluminum alloy was investigated.Design/methodology/approach: The effects of the high-speed twin roll caster on alleviating the deterioration of mechanical properties by impurities were investigated. Properties of the cast strip were investigated by metalography, a tension test, and a bending test.Findings: A vertical type twin roll caster for strip casting of aluminum alloys was devised. The strip, which was thinner than 3 mm, could be cast at speeds higher than 60 m/min. Features of the twin roll casters are as below. Copper rolls were used and lubricant was not used in order to increase the casting speed. A casting nozzle was used to set the solidification length precisely. Heat transfer between melt and the roll was improved by hydrostatic pressure of the melt. Separating force was very small in order to prevent sticking of the strip to the roll. Low superheat casting was carried out in order to improve microstructure of the strip. In the present study, effectiveness of a high-speed and high-cooling rate twin roll caster of the present study for recycling aluminum alloy was investigated. Fe was added as impurity to 6063 and A356. The roll caster of the present study was useful to decrease the influence of impurity of Fe.Research limitations/implications: A high-speed twin roll caster of vertical type was designed and assembled to cast aluminum alloy thin strip.Originality/value: The results demonstrate that the high-speed twin roll caster can improve the deterioration by impurities.

  19. Modelling of Mould Filling and Solidification of Castings

    Institute of Scientific and Technical Information of China (English)

    Xu Zhian

    2000-01-01

    An experimental casting for validation has been designed. The casting is composed of two 50×600×2.5 (width×length×thick) thin-wall pieces. One downsprue is located in the middle. A pouring cup with a stopper is used. This design allows to using two different types of moulds simultaneously. An Al-10%Si alloy has been poured at different temperatures. Two effects have been studied: one is the pouring temperature and the other is the moulding method (namely by machine or manually). The filling length is proportional to the pouring temperature. The influence of different moulding methods on mould filling is more complicated. The filling length in the manual-made mould is 1.5 times as long as the one in the machine-made mould due to the different thermal conductivities. Vents have little influence. A finite volume based computer code which can simulate fluid flow during mould filling coupled with heat transfer as well as solidification has been developed in WTCM Foundry Center.. The code can predict cold shut during mould filling and shrinkage defects during solidification. The simulated results are in good agreement with the experiments.In the second part of the paper, an example is given which illustrates how to use computer simulation to aid designing the casting system. The final computational result is compared with the industrial casting. The process of designing castings by using simulation is completely different from the traditional way. The computer aided casting design offers the possibility to obtain a sound casting from the first time.

  20. Control of chilling tendency in grey cast iron reuse

    Directory of Open Access Journals (Sweden)

    Saliu Ojo Seidu

    2013-02-01

    Full Text Available In grey cast iron remelt and recycling, white iron can result in the cast product if careful control of the chilling tendency is not ensured. Many jobbing foundries are constrained in furnace types and available foundry additives that the operation always results in white irons. This study is towards ensuring grey iron is reproduced from cast iron scrap auto engine blocks, when using a diesel fired rotary furnace and a FeSi alloy for structural modification (inoculation. With varying addition rate of the FeSi alloy to the tapped molten metal, chill wedge tests were performed on two different wedge samples of type W (according to ASTM A367- wedge test with cooling modulus of 0.45 cm (W3½ and 0.54 cm (W4. The carbon equivalents for the test casts were within hypoeutectic range (3.85 wt. (% to 4.11 wt. (%. In the W4 wedge sample, at 2.0 wt. (% addition rate of the FeSi alloy, the relative clear chill was totally reduced to zero from 19.76%, while the relative mottled chill was brought down to 9.59% from 33.71%. The microstructure from the cast at this level of addition was free of carbidic phases; it shows randomly oriented graphite flakes evenly distributed in the iron matrix. Hardness assessment shows that increasing rate of FeSi addition results in decreasing hardness, with maximum effect at 2.0 wt. (% addition. With equivalent aspect ratio (cooling modulus in a target cast product, this addition rate for this FeSi alloy under this furnace condition will attain graphitized microstructure in the cast product.