What is investment casting? Investment casting is also called lost wax casting, normally on the wax pattern surface coat with several layers of refractory material, waiting after its hardened and dry. Then melting the wax pattern and making the shell, after roasting and pouring,a method for obtaining a casting parts. Because of the high precision on the size of the castings and good surface finish, so it is also called “investment precision casting”.
Investment casting can be divided into: Water glass casting process; silica sol casting process; Composite casting process according to different shell material. The composite process is a kind of casting process between water glass and silica sol. In which composite process which use silica sol in the first two layers, when the shell is dipped, and latter several layers using water glass.