What is the developing history of investment casting?

Investment casting method is used to produce cast steel products,investment castings, precision investment casting,machine tool castings and so on for different industrial use.Investment casting can produce items in sizes and shapes that cannot be made by other metal casting methods.
During the Second World War a huge demand for investment casting developed to furnish the jet propulsion systems in airplanes.Investment casting of mechanical parts later found its way to civilian aircraft.
Since the invention of the jet engine, there has been increased interest in investment casting by the aerospace industry.It is reliable for its ability to produce accurate dimensional,high-precision casting parts. Increased resistance to corrosion and lower maintenance costs are the hallmarks of aluminum alloy investment casting.Investment casting can produce high-precision mechanical and engineering parts quickly and in large quantities.
The process of investment casting is very simple.Plaster slurry is applied to a design formed from a fusible substance like wax. As the plaster bakes, the wax melts out.The name 'lost-wax casting' is a perfect description of the process.The internal cavity thus formed is the shell or mould for the aluminum investment casting.The molten aluminum is poured into the cavity.After cooling,the external mold is broken and the casting is retained.
Investment casting has many advantages.It is a very versatile process and produces a wide range of products for a variety of industries.It allows the selection of suitable alloys,such as aluminum alloys. Investment casting offers the greatest design flexibility for producing complex structures.This flexibility cannot be found in other metal casting methods.This allows the engineers and designers to concentrate on the functional aspect of the part rather than its manufacture.
Investment casting gives a lightweight option for precision parts.The precise dimensional control also allows the casting to be used with little or no machining for final detailing.It produces a surface finish that cannot be obtained by machining or sanding.It also saves on cost and time,as it needs no welding,assembling or finishing work.It also saves on the need to produce multiple parts and to weld them together as a unit.

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