... oxide grit No. 14 to 220 # Aluminum oxide is a tough, hard material (Mohs hardness 9) with high strength, ... and good thermal conductivity. Fused alumina is widely used as a raw material in refractories, ceramics shapes, grinding wheels, sandpaper, ... 220#, 240#,320#,400#,600#,800# Henan Sicheng Co., Ltd, a comprehensive company integrated in production, research and trade, is specialized in ...