Silicon Carbide Types

Silicon carbide can divided into green silicon carbide and black silicon carbide.

Green silicon carbide is an extremely hard (Knoop 2600 or Mohs 9.4) man made mineral that possesses high thermal conductivity (100 W/m-K). It also has high strength at elevated temperatures (at 1000°C, Green SiC is 7.5 times stronger than Al2O3). Green silicon carbide has a modulus of elasticity of 410 GPa, with no decrease in strength up to 1600°C, and it does not melt at normal pressures but instead dissociates at 2815.5°C.

Green silicon carbide is produced as the same type as the black silicon carbide, except the different raw materials. It is crystallization have higher purity and hardness. Green silicon carbide is suitable for processing hard alloy, metallic and non-metallic materials with hard and brittle feature such as copper, brass, aluminium, magnesium, jewel, optical glass, ceramics, etc. Super micropower of it is also a kind of ceramics material.
Green silicon carbide is an entirely new batch composition made from Silica sand and coke, and is extremely pure. It can be manufactured in many complex bonded shapes, which are utilized for super refractory purposes. Green silicon carbide is also ideal for a wide variety of abrasive applications.

Black silicon carbide contains some free silicon and carbon and is not as pure as green silicon carbide. A common use of black silicon carbide is in abrasive wheels or refractoriness. It is manufactured in many complex bonded shapes, which are utilized for super-refractory purposes. Black silicon carbide is also ideal for a wide variety of applications.

Black silicon carbide is produced at high temperature in an electric resistance type furnace with quarts sand and petroleum coke as its main raw materials. Its hardness is between fused alumina and synthetic diamond. 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.

Black silicon carbide have a higher hardness than corundum abrasive. It has sharp knife-edge and friable character as well as good thermal conductivity and quick heat dissipation. The self-sharpening characteristics of black silicon carbide is better than corundum abrasive. It is suitable for machining and production of ceramics, resin, rubber grinding wheel, refractory material and grinding of gray cast iron, white cast iron, bronze, brass, ore, bone, glass, leather, rubber, plastic and the thermal sensitive material. Black silicon carbide abrasive is also suitable for sandblasting, dry grinding, free grinding as well as cutting and making jewelry, jade, agate and so on.