What are the differences in color, use and structure of silicon carbide?

Silicon carbide is a kind of carbide discovered occasionally by American engineer e.g. Acheson when he fused diamond in 1891. At that time, it was mistakenly thought to be a compound with corundum, so it was named emery.black silicon carbide price In 1893, Acheson developed an industrial method for the manufacture of silicon carbide. The resistance furnace with carbon material as its core was electrified to heat the mixture of SiO2 and carbon, and the patent method for producing silicon carbide was reflected (U.S. Patent No. 492767).

Silicon carbide can be divided into different categories according to color, use and structure.

Pure silicon carbide is a colorless crystal. Industrial silicon carbide is colorless, light yellow, light green, dark green or light blue, dark blue or even black. According to the abrasives profession, silicon carbide is divided into black silicon carbide and green silicon carbide according to color. The colorless and dark green silicon carbide are classified as green silicon carbide; the light blue to black silicon carbide is classified as black silicon carbide.

The reason of polychromatic silicon carbide is related to the existence of various impurities. Industrial silicon carbide generally contains about 2% impurities, including silicon dioxide, silicon, iron, aluminum, calcium, magnesium, carbon, etc. When there is more carbon in the crystal, the crystal is black. Green silicon carbide is brittle and black silicon carbide is tough. The grinding ability of the former is slightly higher than that of the latter. According to the particle size, the products are divided into different grades. According to the professional rules of abrasives in China, there are 17 grades of black silicon carbide and 21 grades of green silicon carbide. Abrasives with No. 80 and above are called abrasive grains, and abrasives with No. 100-280 are called grinding powder.

According to different uses: silicon carbide is divided into abrasive, refractory materials, deoxidizer, electrical silicon carbide, etc. The SiC content of SiC should be above 98%.

Silicon carbide for refractory materials can be divided into (1) black silicon carbide for advanced refractory materials, and its SiC content is completely the same as that for abrasive materials; (2) black silicon carbide for secondary refractory materials, with SiC content greater than 90%; and (3) black silicon carbide for low-grade refractory materials, with SiC content greater than 83%.where to buy silicon carbide powder Generally, the content of SiC should be more than 90%. However, if the content of SiC is more than 45%, it can also be used as deoxidizer. There are two kinds of silicon carbide for deoxidizer: powder and molding block. The powder deoxidizer black silicon carbide has two kinds of particle size: 4-0.5mm and 0.5-0.1mm.

There are two main types of silicon carbide for electrical engineering: (1) green silicon carbide for electric heating elements, its essence is the same as green silicon carbide for abrasives. (2) Silicon carbide used in arrester has special electric function requirements, which is different from black silicon carbide for abrasive materials.