Boron carbide (chemical formula approximately B4C) is an extremely hard boron–carbon ceramic and covalent material used in tank armor, bulletproof vests, engine sabotage powders,as well as numerous industrial applications. With a Vickers hardness of >30 GPa, it is one of the hardest known materials, behind cubic boron nitride and diamond.
B 4584 (OTTO) Boron carbide, 100µm, ≥98% Cas 12069-32-8 - used in refractory applications due to its high melting point and thermal stability.