The main uses of silicon carbide are:
(1) Abrasive - mainly because silicon carbide has high hardness, chemical stability and certain toughness, silicon carbide can be used to manufacture consolidated abrasives, coated abrasives and free grinding, so as to process glass, ceramics, stone, cast iron and some non-ferrous metals, cemented carbide, titanium alloy, high-speed steel cutting tools and grinding wheels.
(2) Refractory and corrosion-resistant materials - mainly because silicon carbide has high melting point (degree of decomposition), chemical inertia and thermal vibration resistance, silicon carbide can be used in many kinds of silicon carbide ceramic products, such as shed plates and saggers used in grinding tools and ceramic products firing kilns, silicon carbide bricks used in vertical cylinder distillation furnaces in zinc smelting industry, aluminum electrolytic cell liners, crucibles, small pieces of furnace materials and so on.
(3) Chemical application - because silicon carbide can decompose in molten steel and react with free oxygen and metal oxides in molten steel to produce carbon monoxide and silicon containing slag. Therefore, it can be used as a purifying agent for smelting steel, that is, as a deoxidizer for steelmaking and a structural modifier for cast iron. This generally uses low-purity silicon carbide to reduce costs.
(4) Electrical applications - used as heating elements, nonlinear resistance elements and high semiconductor materials. Heating elements such as silicon carbide rod (applicable to various electric furnaces working at 1100 ~ 1500 ℃), nonlinear resistance elements and various lightning protection valve pieces.
(5) Others are prepared into far-infrared radiation coating or made into silicon carbide plate in far-infrared radiation dryer.
