Black silicon carbide is mainly made of quartz sand, petroleum coke, smelted by above 2500 in the electric furnace, the hardeness is between corundum and diamond, the hardness is superior to corundum. It has the fuction of conductivity and thermal conductivity. It is suitable to prosses metals and non-metallic materials. Such as gray cast iron, non-ferrous metals, stone, leather, rubber and so on. It also widely used in refractories, metallurgical additives.