Silicon carbide brick

Silicon carbide brick is a refractory product made of silicon carbide as the main raw material. Silicon carbide content 72% ~ 99%. General selection of black silicon carbide (SiC content more than 96%) as raw materials, adding binder (or not), through the batching, mixing, molding and sintering process. The main crystal phase is silicon carbide. The main varieties are oxide bonded silicon carbide brick, carbon bonded silicon carbide brick, nitride bonded silicon carbide brick, self bonded silicon carbide brick, recrystallized silicon carbide brick and semi-silicon carbide brick, etc. It is a high-performance refractory material with good wear resistance, corrosion resistance, high temperature strength, good thermal shock stability, high thermal conductivity, small thermal expansion coefficient and other characteristics.

Main classification and application of silicon carbide brick

Clay bonded silicon carbide brick

Clay bonded silicon carbide brick is a refractory product with silicon carbide as the main raw material and clay as the binder. It is characterized by high thermal conductivity, small thermal expansion coefficient, good thermal shock resistance and wear resistance. It is one of the earliest silicon carbide bricks developed. The products are used as ceramic kiln tools (shed boards, supports, saggers, etc.), Muffle covers for Muffle furnaces, furnace lining bricks for aluminum refining furnaces, distillation tanks for zinc distillation furnaces, cement rotary kiln coolers, etc.

Silicon nitride bonded silicon carbide brick

Silicon nitride bonded silicon carbide brick is a refractory product made of SiC and Si powder by nitriding firing. It is characterized by Si3N4 as a combination phase. Si3N4 exists among SiC grains as acicular or fibrous crystals and is an important new refractory material. Silicon nitride bonded silicon carbide brick has good alkali corrosion resistance, melt cryolite wettability, oxidation resistance, wear resistance, high thermal conductivity, thermal shock resistance and very low electrical conductivity.

Silicon-nitride bonded silicon carbide brick is mainly used as the lining of the lower furnace body of the blast furnace, and its service life is more than 1 times longer than that of the traditional refractory materials. In addition, it can be used as the lining of aluminum reduction electrolytic cell and ceramic kiln tools, which has the advantages of energy saving, life improvement and no environmental pollution. 

Recrystallized silicon carbide products

Recrystallized (recrystallized) silicon carbide products are refractory products made of silicon carbide and silicon carbide directly combined. It is characterized by the absence of a second phase and is composed of 100%α-SiC. The chemical composition of the raw material used to manufacture recrystallized silicon carbide is as follows: SiC 99.5%, free C 0.2%, Fe 0.08%, free SiO2 0.08%.

Recrystallized silicon carbide products are mainly used as kiln tools, which have the advantages of energy saving, increasing the effective volume of the kiln, shortening the firing cycle, improving the production efficiency of the kiln, and high economic benefits. They can also be used as burner nozzle head, ceramic radiation heating tube, element protection tube (especially for atmosphere furnace).