Chemical properties of silicon Carbide ceramic materials

When the temperature in the oxygen reaction reaches 1300℃, a protective layer of silica is formed on the surface of the silicon carbide crystal. With the thickening of the protective layer, the internal silicon carbide is resistant to continue to combine, so that the silicon carbide has good chemical resistance. In acid resistance, alkali resistance, compound resistance, silicon carbide due to the role of silicon dioxide protective film, acid resistance is strong, alkali resistance is poor.

Physical properties of silicon carbide ceramic materials

The various sic crystals have a similar density, usually 3.20 g/mm³. Silicon carbide has a hardness of 9.5 Mohs and Knoo hardness of 2670-2815 kg/mm, higher than corundum among abrades and second only to diamond, cubic boron nitride and boron carbide. The thermal conductivity and thermal shock resistance of silicon carbide ceramics are very high, and the thermal expansion parameter is small, so silicon carbide ceramics is a kind of high-quality refractory materials.