Mullite is a high-grade raw material with uniform thermal expansion, good thermal shock resistance, high refractoriness under pressure, low creep, high hardness and good chemical resistance.
The synthesis methods of mullite can be divided into sintering method and electric melting method. Artificial mullite is made by sintering method and electric melting method. The sintering method uses silica, kaolinite, high-alumina bauxite and industrial alumina as raw materials, and mixes them according to the theoretical composition of mullite. After grinding and fully mixing, the blank is made and fired at 1700~1750℃ in a rotary kiln or tunnel kiln. The electric melting method is to mix industrial alumina, sintered high-quality bauxite, high-purity silica, etc. according to the composition of mullite, mix them evenly, and then put them into an electric arc furnace for melting. Both production methods can produce products containing more than 86% mullite.
Since mullite has good high-temperature mechanical and thermal properties, synthetic mullite and its products have the advantages of high density and purity, high high-temperature structural strength, low high-temperature creep rate, small thermal expansion rate, strong chemical erosion resistance, thermal shock resistance, etc. Therefore, it is mostly used in refractory materials, ceramics, metallurgy, casting, electronics and other industries, suitable for the lining of petroleum cracking furnaces, metallurgical hot air furnaces, ceramic roller kilns, tunnel kilns, electric porcelain drawer kilns, glass crucible kilns and various electric furnaces, which can directly contact the flame. After being tested and used by relevant technical supervision departments, the products have reached the technical indicators of similar foreign products.
The sintered mullite produced by Haixin Refractory has the dual advantages of "performance improvement + cost optimization", which truly achieves energy-saving refractory production. We continue to improve and break through ourselves, and contribute our own strength to the innovation and development of the refractory industry.