Investment Castings also called precision casting is a kind of industrial application. This type of process is based on the fundamentals of an old metal-forming technique called lost-wax casting. Investment casting is generally applied to create small castings, but on quite a few occasions it has even helped in completing aluminum castings of up to 30kg, steel castings of up to 300kg and even large aircraft door frames.

This old manufacturing process of old wax has been around for over 5,000 years and even Egyptians used it to create gold jewelry. Using lost wax process can even benefit creation of intricate shapes and it can perform such tasks with great accuracy and precision. Hence, it is not surprising that investment casting is also referred to precession casting.

To make the investment casting a pattern is created from wax or any other material that can be easily melted. A mould is created out of this pattern, which is also known as master plan and then wax patterns are produced. The process involves pouring wax into a mold and ensuring it is evenly coats the inner side of the mold and forms a skin. A variety of wax patterns can be created and used as a cast simultaneously or different patterns may be formed and then re-arranged to make one complex pattern.

Once the wax pattern is created, the ceramic mould needs to be made, which is prepared from refractory materials such as zircon, alumina, silica and aluminum silicates. The investment-casting cluster is soaked in a mixture of refractory material and thereby giving it a smooth finish. The investment casting has to be completely dried which may take up to approximately 48 hours and then the wax is melted out in a furnace. 

The model is heated under a high temperature to remove moisture or residue. The investment casting is generally placed in a sand filled container and air pressure is applied to it finally the investment casting is released from the shell by chemically dissolving it or using the media blasted process.

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