... point 24500c, 3.density 2.51g/cm3 Boron Carbide, a black powder, is the hardest of the ... with either acids or alkali etc. Boron carbide is widely used to grind and polish hard ... metal alloy, super-hard metal, high carbide steel, jewel, hard ceramic and other hard materials, ... ceramic, boron steel, boron alloy and for special welding and refractory materials.Packing 50kgs packed in iron drum ...