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Materials whose physical and chemical properties allow them to be used in high temperature environment are called refractory materials. Refractory materials are widely used in metallurgy, chemical industry, petroleum, machinery manufacturing, silicate, power and other industrial fields. The largest amount is used in the metallurgical industry, accounting for 50% ~ 60% of the total output. Materials whose physical and chemical properties allow them to be used in high temperature environment are called refractory materials. Refractory materials are widely used in metallurgy, chemical industry, petroleum, machinery manufacturing, silicate