... , high temperature resistant, anti-oxidation, corrosion resistance, low creep Technology: Brown fused alumina use high-quality bauxite as main raw material, it is ... ,that is, 320 # The physical properties of corundum Item IndicatorsColorDark brown (dark blue after calcining)Crystal shapeTrigonal systemHardness (Mo's)≥9 ... Density (g/cm3)≥3. 90Linear expansion coefficient (0-1600 )79 Brown fused alumina