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Medical implants by using RP and investment casting technologies  [PDF]
Milan Horacek,Ondrej Charvat,Tomas Pavelka
China Foundry , 2011,
Abstract: The paper deals with the production technology of knee joint replacement by using rapid prototyping technology. The aim of the work is to outline the manufacturing technology intended for prototype production with the use of rapid prototyping and investment casting technology for use in orthopaedics and the surgery of knee joint replacement. The research results should make an effective contribution in the attempts to minimize the invasive surgical procedure, shorten the production of knee joint replacement as well as reduce the cost. At present, the research is focused on the preparation of STL data from CT (Computed Tomography) and verification of the production technology of prototypes made using available RP technology and its evaluation.
Plaster mould casting process of AlSi11 alloy  [PDF]
R. W?adysiak,M. Pawlak
Archives of Foundry Engineering , 2009,
Abstract: The paper presents the results of the crystallization and cooling process of AlSi11 silumin in the plaster mould with TDA method and describes the impact of the preparation of plaster mould and liquid silumin on received microstructure and quality of casting. The effect of the pouring temperature of silumin on porosity and filling of mould cavity was investigated. The nature and rate of change of temperature in casting and the formation of the microstructure was shown by means thermal and derivative curves. Through the use of control samples in range of a thickness of 0.5 ÷ 4 mm confirmed the possibility of obtaining thin-walled silumin castings in pre-heated before plaster moulds. It has been proved that changing the parameters of pre-treatment moulds of gypsum, the pouring temperature and modification of silumin you can control the crystallization process, obtained microstructure and properties Rm, RP02 and HB.
Influence of the cordierite lining on the lost foam casting process  [PDF]
Trumbulovi? Ljiljana,Guli?ija Zvonko,A?imovi?-Pavlovi? Zagorka,Andri? Lj.
Journal of Mining and Metallurgy, Section B : Metallurgy , 2003, DOI: 10.2298/jmmb0304475t
Abstract: This paper discuss the influence of the refractory cordierite lining on the structure and mechanical properties of Al-Si and Al-Cu casings obtained from the Lost foam casting process. So far there has not been any report of the research on cordierite lining in the literature and moreover the cordierite ceramics have never been used in foundries. In the light of these facts this paper investigates the possibility of using cordierite for manufacturing evaporable model refractory linings. Our results indicate that the application of cordierite ceramics is comparable to talc-based refractory linings in both Al-Cu and Al-Si castings, while cordierites are favorable in Al-Cu case due to their higher melting temperature.
Recycled materials for the investment casting process  [PDF]
H. Matysiak,R. Haratym,R. Biernacki
Archives of Foundry Engineering , 2010,
Abstract: The possibility of using materials in the investment casting process is discussed within this paper. Wax recycled from the assembles andaluminosilicates recycled from the shell systems are the materials of interest. The recycling process was performed with the view on thefallowing issues: decreasing the amount of waste and transforming the waste into the production material that could be used in theinvestment casting process on the regular basis. In addition, the ecological aspect of the recycling process is an advantage to the proposal.
NUMERICAL SIMULATION OF CASTING PROCESS
LL Chen,RX Liu,HT Lin College of Materials Science,Engineering,Huazhong University of Science,Technology,Wuhan,China,
L.L. Chen
,R.X. Liu and H.T. Lin College of Materials Science and Engineering,Huazhong University of Science and Technology,Wuhan,China

金属学报(英文版) , 2000,
Abstract: In this paper, the development status of casting numerical simulation technology is introduced. In additional, mathematical model, solution method, initial condition, boundary condition and defect predicting scheme of foundry process are also analyzed, which include the mold filling process, solidification process and the process coupling fluid flow with heat transfer. Finally, a practical casting is taken out to show how to predict defects and optimize foundry process with numerical simulation technology.
Optimization of the investment casting process  [PDF]
M. Martinez-Hernandez,A. Juarez-Hernandez,M. Ayala Vera,J. Ayala-Cazares
Metalurgija , 2012,
Abstract: Rapid prototyping is an important technique for manufacturing. This work refers to the manufacture of hollow patterns made of polymeric materials by rapid prototyping technologies for its use in the preparation of ceramic molds in the investment casting process. This work is focused on the development of a process for manufacturing patterns different from those that currently exist due to its hollow interior design, allowing its direct use in the fabrication of ceramic molds; avoiding cracking and fracture during the investment casting process, which is an important process for the foundry industry.
Quality assessment of expendable patterns in the investment casting process  [PDF]
H. Matysiak,R. Haratym,K.J. Kurzydlowski,R. Biernacki
Archives of Foundry Engineering , 2010,
Abstract: assessment of patterns mixtures contraction as a function of solidification module. These features were verified on step-shaped pat-terns. Patterns mixtures made on the basis of hard waxes were selected for tests and compared with the domestic mixture based on paraffin and stearin (PS) as well as with the PS-mixture to which the material of used patterns from the WSK Rzeszow factory was added.The selected tests enable a quick assessment of whether the pattern mixture quality meets the requirements of optimum size accuracy and good quality of casting surfaces.
Enrichment of Casting Surface in Founding Process  [PDF]
J. Szajnar,P. Wróbel,T. Wróbel
Archives of Foundry Engineering , 2007,
Abstract: A lot of cast steel and cast iron properties, also usable, depend on physical and chemical properties of surface layer, such as: hardness, corrosion resistance, abrasive wear resistance. The paper presents directly method of surface enrichment on casting in founding process. Layer in form of high-speed steel HS 18–0–1plate was placed on G25CrSiMnMoNi 4–4–4–2,5–4 cast steel hammer of crusher. To investigations it was used light microscopy and scanning electron microscope. Microanalysis of chemical microanalysis of chemical composition and hardness measurements of transient zone between cast steel and steel were made. Analysis of research result show that, exists possibility of increase in hardness and abrasive wear resistance by put on casting surface a tool steel or sintered carbides plates, which are from scrap after waste of turning tool or face milling cutter. Moreover, applied activated alloy is very useful in this method of casting surface enrichment directly in founding process.
Geometric accuracy of wax bade models manufactured in silicon moulds  [PDF]
G. Budzik,H. Matysiak
Archives of Foundry Engineering , 2010,
Abstract: The article presents the test results of the geometric accuracy of wax blade models manufactured in silicon moulds in the Rapid Tooling process, with the application of the Vacuum Casting technology. In batch production casting waxes are designed for the manufacture of models and components of model sets through injection into a metal die. The objective of the tests was to determine the possibility of using traditional wax for the production of casting models in the rapid prototyping process. Blade models made of five types of casting wax were measured. The definition of the geometric accuracy of wax blade models makes it possible to introduce individual modifications aimed at improving their shape in order to increase the dimensional accuracy of blade models manufactured in the rapid prototyping process.
An Approximation for the rp-Process  [PDF]
F. Rembges,C. Freiburghaus,T. Rauscher,F. -K. Thielemann,H. Schatz,M. Wiescher
Physics , 1997, DOI: 10.1086/304300
Abstract: Hot (explosive) hydrogen burning or the Rapid Proton Capture Process (rp-process) occurs in a number of astrophysical environments. Novae and X-ray bursts are the most prominent ones, but accretion disks around black holes and other sites are candidates as well. The expensive and often multidimensional hydro calculations for such events require an accurate prediction of the thermonuclear energy generation, while avoiding full nucleosynthesis network calculations. In the present investigation we present an approximation scheme applicable in a temperature range which covers the whole range of all presently known astrophysical sites. It is based on the concept of slowly varying hydrogen and helium abundances and assumes a kind of local steady flow by requiring that all reactions entering and leaving a nucleus add up to a zero flux. This scheme can adapt itself automatically and covers situations at low temperatures, characterized by a steady flow of reactions, as well as high temperature regimes where a $(p,\gamma)-(\gamma,p)$-equilibrium is established. In addition to a gain of a factor of 15 in computational speed over a full network calculation, and an energy generation accurate to more than 15 %, this scheme also allows to predict correctly individual isotopic abundances. Thus, it delivers all features of a full network at a highly reduced cost and can easily be implemented in hydro calculations.
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