... . big bulk density; 3. high-strength,grinding, resisting alkali or sour. Corundum refractories ItemsWhite corundumChrome-corundumBrown corundumZR-corundumZR-mulliteYL-corundumAL2O3%90 ... performance, big bulk density, high-strength,grinding, resisting alkali or sour.UsageWidely used in furnace kilns of metallurgy, chemical engineering,elecstric ...