... high hardness, wear resistance, high strength characteristics, in the chemical system, used for a variety of reaction vessels and pipelines, chemical ... pencil lead, etc.; do tool, die grinding, bullet-proof material, the human body joints, sealing ring mold.(3) Corundum heat preservation material , such ... 63#94.0 Max0.5 Max1.8 Max4.0 Max—For refractorySize sand0-1mm1-3mm3-5mm5-8mm8-12mm95 Min0.3 Max1 ...