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Showing 1 to 20 of 23 for “"investment casting"”.
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Towards inert cores for investment casting
… yttrium and lanthanum in the blade alloy. During casting these reactive elements are easily lost from the alloy by reaction with both the core and shell of the mould. This study tests several candidate core formulations for their ability to retain reactive element levels in the alloy after …
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Analysis of various rapid prototyping techniques for investment casting
… wax material as a master pattern in the investment casting (IC) process. This is because the RP technology allows simple to complex patterns to be fabricated directly from a computer model in a shorter time without using any hard tooling. However, quality of the RP patterns remains to be …
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Improved sol based ceramic moulds for use in investment casting
… into the mechanisms of failure of silica bonded investment casting moulds, with the aim of reducing failure rates for larger components. The analysis begins with a detailed microstructural examination of a current commercial mould system using scanning electron microscopy and other allied …
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Investigation of rapid freeze prototyping and investment casting with ice patterns
… to agree well with simulation results.</p> <p>Investment casting with ice patterns is similar to that with wax patterns but with significant process differences. An interface agent can be coated around the ice pattern to protect it from damage during the process. To compensate for the thickness …
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Applications of Investment Casting as a Manufacturing Process for Injection Mold Tooling
An exploration in the utility of investment casting aluminum molds for small-scale plastic injection molding, compared against traditional machining methods for these molds. The intention of this study was to determine if lost wax casting could provide a more efficient option for tool …
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Feasibility study of investment casting pattern design by means of three dimensional printing
Thesis (B.S.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1989.
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Collapsibility behaviour of ABS P400 and PMMA used as sacrificial pattern in direct investment casting process
The feasibility of the Investment Casting (IC) process has been choose to be vital route in producing the metal alloy products. However, less report regarding the feasibility of portable Additive Manufacturing (AM) machines to be employed in casting process. Sacrificial wax pattern in casting …
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Improving the strength of 3DP parts and development of controlled strength cellular structure investment casting shell
… powder bed in creating a 3DP part) for use in investment casting process. The print styles that were created optimized line to line interaction between the printed lines, binder overlap, and the amount of unprinted powder surrounding the printed features. The strength of the parts are measured …
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Three dimensional printing of ceramic molds with accurate surface macro-textures for investment casting of orthopaedic implants
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1995.
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Effects of flux application and melting parameters in investment casting of pure aluminium by in-situ melting technique
Investment cast aluminium suffers porosity defect attributed to the complex combination of various factors including melt quality, casting process parameter and pouring technique. Even though, melt treatment and controlled of the process parameter have promising result, however turbulence developed …
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Part I: In-situ fluorometric quantification of microalgal neutral lipids Part II: Thermal degradation behavior of investment casting polymer patterns
… (SLA) patterns, that are used in investment casting. Density, elastic modulus, expansion coefficient, thermal degradation behavior, etc. were experimentally investigated for their effects on metal casting quality. The reduction in toxic hydrogen cyanide (HCN) generated during …
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Vibration assisted filling of thin section castings
… control parameters of the vibration in thin wall investment casting is key to producing sound casting (one free of misrun defects). It's also a central issue for study in this thesis. The filling capability in thin wall investment casting method was assessed in relation to metal head. It was found …
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Economic Analysis of 3D-Printed Ceramic Cores for GasTurbine Investment Castings
… engines, internal cooling channels are formed by investment casting with sacrificial ceramic cores. The hot injection and pressing techniques traditionally used to manufacture ceramic cores have long lead times and high up-front costs, motivating an interest to form cores via additive …
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Grain refinement in cast titanium 6-aluminium 4-vanadium by hydrogenation, deformation and recrystallisation
… costly to machine components from wrought stock. Investment casting is an alternative component manufacturing route but cast components have inferior mechanical properties to their wrought counterparts. Therefore, microstructure refinement is required in order to optimize these mechanical …
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An assessment of stingless beeswax as a pattern material in ancient Mesoamerican lost-wax casting
… that these items were made by the process of investment casting, or "lost wax" casting, by which a wax model of the object is created, and a ceramic mold is built around it. The wax is melted out to allow for the pouring of the molten metal. Considerable research has focused on the alloy …
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Modelling directional casting processes in which heat conduction and cavity radiation are the dominant modes of heat transfer
Directional investment casting processes involve complex interactions of various mechanisms of heat and mass thansfer in spatially complex domains and in the presence of a change of phase. In particular, the transfer of heat within the furnace occurs in the form of conduction, convection and …
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Improving the manufacturing yield of investment cast turbine blades through robust design
… of turbine blades is often outsourced to investment casting foundries by aerospace companies that design and build jet engines. Aerospace companies have found that casting defects are an important cost driver in the price that they pay the foundries for the turbine blades. Defect types …
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Recrystallisation in Single Crystal Nickel-Based Superalloys
Plastic strains during investment casting of single crystal Ni-based superalloys arise from differences in thermal contraction between the metal and ceramic mould-and-core. If deformation is above a critical limit, subsequent solution heat treatment of the alloy causes recrystallisation. Crack …
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Understanding surface and sub-surface phenomena in nickel-based superalloy castings
… engines. Single crystal turbine blades are investment cast, followed by a complex series of operations including heat treatment, machining, blasting, etching and polishing to produce a product ready for coating. Coating systems provide environmental protection, tribological resistance and …
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Investigating wetting characteristics on microstructured surfaces for superhydrophobicity and metal microcasting
… masters, so this dissertation describes casting-based microfabrication of metal microstructures and nanostructures. Low melting temperature metal was cast into flexible silicone molds which were themselves cast from microfabricated silicon templates. The flexibility of the silicone mold …
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