Sic is made of silica sand, coke, wood and other raw materials by resistance furnace smelting at high temperature. It has steady chemical composition, anti-abrasion, anti-corrosion, high temperature resistance, shock resistance, good heat conduction and so on. Now SiC produced by China’s industry can be divided into black SiC and green SiC. They are mainly used in four big application fields: functional ceramics, refractories, abrasives and metallurgical raw materials .