Characters: Aluminum oxide, commonly known as corundum, is a high melting point, white powder, can be used as a refractory material. It is a typical gender oxides, soluble in strong acid and strong alkali. Its most stable crystal form is the α-Al2O3 and pure aluminum oxide is a colorless or white crystals, the sintering densification of Al2O3 ceramic has good hardness, high temperature anti-oxidation, anti-radical quenching heat, high mechanical strength, good chemical stability and high insulation. So, it has a wide range of usage.