Silicon carbide due to stable chemical properties, high thermal conductivity, small thermal expansion coefficient, good wear resistance, in addition to abrasives, there are many other uses, such as: silicon carbide powder coated on the inner wall of the turbine impeller or cylinder block by a special process, which can improve its wear resistance and extend the service life by 1~2 times; The high-grade refractory materials used to make them are resistant to thermal shock, small in size, light in weight and high in strength, and have good energy-saving effects. Low-grade silicon carbide (containing about 85% SiC) is an excellent oxygen absorber, speeding up steelmaking and facilitating chemical composition control to improve steel quality. In addition, silicon carbide is also widely used in the production of silicon carbon rods, electric heating elements.
Silicon carbide has a great hardness, 9.5 on the Mohs scale, second only to the world’s hardest diamond (grade 10), has excellent thermal conductivity, is a semiconductor, and can resist oxidation at high temperatures.
Silicon carbide has at least 70 crystalline forms. α-silicon carbide is the most common homogeneous isocrystal, formed at a high temperature above 2000 °C, with a hexagonal crystal structure (similar to fibrous zinc ore). β-Silicon carbide, cubic crystal structure, similar to diamond, is formed at temperatures below 2000°C.
