Green silicon carbide is made of petroleum coke and high-quality silica as the main raw materials, with salt as an additive, and is smelted in a resistance furnace at high temperature. The smelted crystals are of high purity and high hardness, which is between that of corundum and diamond, and has a mechanical strength higher than that of corundum.
Production process of green silicon carbide：
Green silicon carbide is manufactured using the same method as black silicon carbide, but requires raw materials of higher purity. It is also formed in a resistance furnace at temperatures around 2200°C. It is green, translucent, and has a hexagonal crystal structure. Its Si content is higher than that of black silicon carbide. Its physical properties are similar to those of black silicon carbide, but it is slightly more brittle than black silicon carbide. It also has better thermal conductivity and semiconductor properties.
Industrial green silicon carbide varies in transparency and purity, depending on the type and content of impurities. Its crystal structure is classified as hexagonal or rhombohedral α-SiC and cubic β-SiC. α-SiC forms many different variants due to the different stacking sequences of carbon and silicon atoms in its crystal structure, with over 70 types discovered. β-SiC transforms into α-SiC at temperatures above 2100°C. The industrial production of green silicon carbide uses high-quality quartz sand and petroleum coke in a resistance furnace. The resulting green silicon carbide blocks are crushed, washed with acids and alkalis, magnetically separated, and sieved or water-selected to produce products of various particle sizes.
Green silicon carbide specific uses:
1. As an abrasive, it can be used to make grinding tools such as grinding wheels, oilstones, grinding heads, and sanding tiles.
2. As a metallurgical deoxidizer and high-temperature resistant material.
3. High-purity single crystals can be used in semiconductor manufacturing and silicon carbide fiber production.
4. It is primarily used in crystal grinding, single-crystal silicon wire cutting, ceramic polishing, precision grinding wheel manufacturing, and filling and modifying plastic products, among other applications.
5. It can be used for cutting and precision grinding of crystals, precision grinding of hard glass, slicing of single-crystal silicon and polycrystalline silicon rods, precision grinding of single-crystal silicon wafers, machining of superhard metals, machining of soft metals such as copper and copper alloys, and machining of various resin materials.
6. It is an ideal material for super-fine lapping oilstones. It has excellent thermal conductivity and high-temperature resistance.
