Alumina ceramic is a kind of special ceramic slice, which is made of alumina as raw material, rare metal oxide as flux and roasted at more than 1000 degrees. Because of its high content of metal material, compact structure and special properties, it is called special ceramics. The product is a close packed hexagonal structure composed of oxygen ions, which is not easy to oxidize and high temperature, so it has higher service temperature than other refractory fiber products, so it has high melting point, high hardness and excellent wear resistance.