Boron carbide (chemical formula approximately b4c) is an extremely hard boronu2013carbon 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. Boron carbide's extra hardness gives it the nickname black diamond. color is black or gray. boron carbide (chemical formula b4c) is an extremely hard ceramic material used in tank armor, bulletproof vests, and numerous industrial applications. 99.9% boron carbide high purity b4c for sputtering target , find complete details about 99.9% boron carbide high purity b4c for sputtering target,high purity b4c,99.9% boron carbide,sputtering target from other metals & metal products supplier or manufacturer-beijing loyaltarget technology co., limited Boron carbide powder b4c bulk & research qty manufacturer. properties, sds, applications, price. free samples program. term contracts & credit cards/paypal accepted.