Silicon carbide black and green silicon carbide base of the two common species, are considered α-SiC. ① black silicon carbide SiC containing about 95% higher than its toughness green silicon carbide, mostly for processing low tensile strength materials such as glass, ceramics, stone, refractory materials, cast black silicon carbide iron and non-ferrous metals. ② green silicon carbide SiC containing more than about 97%, good self-sharpening, mostly for processing carbide, titanium and optical glass, also used for honing cylinder liners and grinding high-speed steel cutting tools. There is also the cubic silicon carbide, which is a special process to take yellow-green crystals, suitable for the production of bearings super abrasive finishing, the surface roughness of a machined from Ra32 ~ 0.16 microns to Ra0.04 ~ 0.02 microns.Fused zirconia mullite Since silicon carbide chemical stability, high thermal conductivity, thermal expansion coefficient, good wear resistance, except for the abrasive used, there are many other uses, such as: a special process the silicon carbide powder coating on the cylinder block of the turbine impeller or wall, can improve the wear resistance and extend the life of 1 to 2 times; for advanced refractory materials, heat shock, small size, light in weight high strength, good energy saving effect. A low-grade silicon carbide (containing about 85% SiC) is an excellent deoxidizer, with its speed steel to accelerate and facilitate control of the chemical White fused aluminum oxide composition, to improve the quality of steel. In addition, silicon carbide heating element is also used extensively for the production of silicon carbide.
Silicon carbide's hardness great, Mohs hardness of 9.5, second only to the world's most hard-diamond (10), has excellent thermal conductivity, is a semiconductor, resistant to oxidation at high temperatures.
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