Black silicon carbide is produced at high temperature in an electric
resistance type furnace with quartz sand and petroleum coke as its main raw
materials. Its hardness is between fused alumina and synthetic diamond. The
mechanical intensity of it is higher than fused alumina. It is brittle and
sharp and has electrical and heat conductivity in some degree. The abrasives
made of it are suitable for working on cast iron, non-ferrous metal, rock,
leather, rubber, etc. It is also broadly used as refractory material and
metallurgical additive