Boron carbide has a variety of applications. Here are some of them: Boron carbide as an abrasive and lapping agent Because of its hardness, boron carbide in the form of powder and pastes is ideally suited for use as an abrasive and lapping agent with a high material removal rate for processing super-hard materials. The application of boron carbide as an abrasive and lapping agent is common in the following fields:
Boron carbide is used for ceramic blasting nozzles Due to boron carbide’s exceptional abrasion resistance, it is, in sintered form, an ideal material for blasting nozzles with uniform blasting power, minimal wear, and a longer service life even when used with very hard abrasive blasting agents like corundum and silicon carbide. Boron carbide ceramic is used as a ballistic protective material Compared to armored steel and aluminum oxide, boron carbide produces similar ballistic protection, but at a much lower weight. Modern military equipment depends on a high degree of hardness, compressive strength, and a high modulus of elasticity coupled with low weight. Boron carbide is a better choice compared to all other alternative materials for this purpose.
Although boron carbide strike face materials behave more glass-like when impacted by high-velocity rounds, it does not affect its superior ballistic performance except against some specific threats where they might underperform.
Boron carbide powder can be produced commercially using either fusion (which involves reducing boron anhydride (B2O3) with carbon, or by magnesiothermic reaction (boron anhydride is made to react with magnesium in the presence of carbon black. In the first reaction, the product forms into a sizable egg-shaped lump at the center of the smelter. This egg-shaped material is removed and crushed, and then milled to produce the grain size that is appropriate for final use. In the case of magnesiothermic reaction, stoichiometric carbide with low granularity is obtained directly, but it has impurities, including up to 2% graphite. Because it is a covalently bonded inorganic compound, boron carbide is difficult to sinter without applying heat and pressure simultaneously. Hence, the boron carbide is often preferably hot-pressed into dense shapes using fine and pure powders (<2 μm) under a vacuum or inert atmosphere at high temperatures (2100–2200°C). Another method for producing boron carbide is pressureless sintering at a very high temperature (2300–2400°C), which is close to the melting point of boron carbide. To help in reducing the temperature required for densification during this process, sintering aids like alumina, Cr, Co, Ni, and glass are added to the powder mix.
