Refractory materials are all made of black silicon carbide. This kind of black silicon carbide is essentially the same as the black silicon carbide used for abrasives, but the uses and technical requirements are different, so it is supplied under a separate brand.
Refractory black silicon carbide is usually divided into three grades
High-grade refractory black silicon carbide
The chemical composition requirements of this grade are exactly the same as those of black silicon carbide for abrasives. It is mainly used to manufacture high-grade silicon carbide products, such as recrystallized silicon carbide products, gas turbine components, nozzles, silicon nitride bonded silicon carbide parts, blast furnace high temperature zone lining materials, high temperature kiln components, high temperature kiln kiln supports, refractory sacks, etc.
Secondary refractory black silicon carbide
Contains more than 90% silicon carbide. It is mainly used to manufacture furnace components that can withstand medium-high temperatures, such as muffle furnace lining materials. In addition to utilizing the heat resistance and thermal conductivity of silicon carbide, these components also use its chemical stability in many occasions.
Low grade refractory black silicon carbide
The silicon carbide content is required to be greater than 83%. It is mainly used for the lining of iron troughs, ladles, etc.
The strength series of refractory silicon carbide is different from that of abrasives. This is because the purpose of the products used in these two industrial sectors is completely different. The requirements for abrasive particle size are relatively strict, and the basic particle size is concentrated to a considerable extent. The coarsest particle size is absolutely not allowed to exist, and there are also considerable restrictions on fine particles. This is the result of considering the grinding efficiency and the surface finish of the grinding process. The particle size requirements of refractory materials focus on the proper distribution of particle size in order to make refractory products with high density and the best strength. The restrictions on individual coarse particles and a few fine particles are relatively wide, and the particle size range is also large.
The production process of refractory black silicon carbide is, in principle, the same as that of abrasive black silicon carbide. However, its crushing, washing, screening, and magnetic separation are relatively crude, and the quality control is not as strict as that of abrasive black silicon carbide, and it does not need to be washed with alkali or acid.
Refractory black silicon carbide has three grades, including silicon carbide materials for each layer of the smelting furnace. Therefore, the comprehensive utilization of the smelting furnace products is better, the thermal utilization rate is higher, and the economic effect is better.
