There are two commonly used basic varieties of silicon carbide, black silicon carbide and green silicon carbide, both of which belong to α-SiC.

Green silicon carbide is basically the same as black silicon carbide, except for the raw materials and manufacturing process. The product is green and translucent, and its hardness and purity are better than black silicon carbide. Its elastic coefficient reaches 410GPa, and it will not dissolve at room temperature and pressure. It will only be consumed when the temperature reaches above 1600°C and decompose when it reaches 2815.5°C.

① Black silicon carbide contains about 98.5% SiC, and its toughness is higher than that of green silicon carbide. It is mostly used to process materials with low tensile strength, such as glass, ceramics, stone, refractory materials, cast iron and non-ferrous metals.

② Green silicon carbide contains more than 99% SiC and has good self-sharpening properties. It is mostly used to process cemented carbide, titanium alloy and optical glass, and is also used for honing cylinder liners and fine grinding high-speed steel tools. In addition, there is cubic silicon carbide, which is a yellow-green crystal made by a special process. The grinding tools used to make it are suitable for superfinishing bearings, and can make the surface roughness from Ra32~0.16 microns to Ra0.04~0.02 microns in one go.

Chemical coefficient of green silicon carbide: Due to its stable chemical properties, high thermal conductivity, small thermal expansion coefficient, and good wear resistance, it has many other uses besides being used as an abrasive. For example, by using a special process to coat silicon carbide powder on the inner wall of the turbine impeller or cylinder body, it can improve its wear resistance and extend its service life by 1~2 times; the high-grade refractory material made from it is resistant to thermal shock, small in size, light in weight, high in strength, and has good energy-saving effects. Low-grade silicon carbide (containing about 85% SiC) is an excellent deoxidizer. It can speed up steelmaking, facilitate control of chemical composition, and improve the quality of steel. In addition, silicon carbide is also widely used in the production of silicon carbon rods for electric heating elements.

Green silicon carbide is suitable for grinding copper, brass, aluminum, gemstones, optical glass, ceramics and other hard alloys, metals and hard and brittle non-metallic materials. Its powder can also be used as ceramic material. Due to the high purity of black silicon carbide, it is also widely used in the manufacture of refractory materials and various abrasive tools.

Applications: Widely used in grinding wheels, aviation fields, sandblasting, coatings, composite materials, compounds, kilns, grinding, polishing, refractory materials, silicon, quartz, etc.