The basic materials of corundum refractories are fused corundum or sintered corundum. the refractory brick containing more than 90% of Al2O3 is called corundum refractory brick. so, corundum refractory brick. Corundum has a high hardness (9 level of Mohs hardness) such as zirconium corundum refractory brick. Corundum refractory brick is resistant to acid well and melting point is also high, also known as pure alumina refractory brick products, , it has a good effect. These are closely related with the structure of the Al - 0 key, titanium corundum refractory brick, and other basic slag. It is used in high temperature oxidizing atmosphere or in reducing atmosphere. the metal and glass solution have good stability. a-Al2O3 is the main material of high temperature refractory brick and high temperature electrical insulating material .