The rapid development of precision casting is to rely on technological developments and the progress made, there is a greater impact on the development of investment casting new materials, new processes, new technologies are many, such as water-soluble core, ceramic core, metal improvements, large castings technology, titanium casting, casting directionally solidified and single crystal, filtration and purification, hot isostatic pressing, rapid prototyping, computer application in investment casting, mechanization and automation. With technology development, investment casting has been able to produce bigger, more refined, thinner, stronger products.
Casting is currently casting method is the most accurate of all kind of molding method, and good repeatability, casting only a small amount of processing. Casting begins with the design and production of wax or other LFC with mold, casting the complexity and size. Generally takes a few weeks to several months. Also obtained after a week in order to get the casting mold. It is mainly used for the production of a few weeks and wax shell, in small batch production sharing expensive tooling costs.
Rapid prototyping technology in precision casting can be divided into three cases, one molding wax or LFC, namely casting prototype for small batch production of complex castings. Product development or trial pieces. The second is the direct shell method, for a small amount of production. Third, rapid prototyping wax mold that female mold for mass production. These methods solve the traditional method of wax mold manufacturing bottlenecks.
Wax mold of laser rapid prototyping (SLS method) using a modeling material for paraffin powder, which process is first covered with a layer of powder on the table, under computer control using a laser beam to selectively sintering (hollow section parts the non-sintered, powder material is still), will be partially sintered together to form a cured part of the solid portion. After the completion of the next layer of a layer. The new layer with the layer is sintered together firmly. After completion of all sintering, to remove excess powder. They get into a wax mold sintering. Features of this process is to adapt to a wide range of material, can be manufactured by casting wax casting wax. Ceramic powder to manufacture ceramic shell, use can be made of pressed metal powder wax mold of the metal mold.
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