superabrasive

Superabrasive refers to materials that are exceptionally hard, significantly harder than conventional abrasives like aluminum oxide or silicon carbide. The primary superabrasives are synthetic diamond and cubic boron nitride (CBN). These materials possess hardness values that are extremely high, making them ideal for cutting, grinding, and polishing very hard materials that are difficult or impossible to machine with traditional abrasives.

Synthetic diamond is produced industrially under high pressure and high temperature (HPHT) or by chemical vapor deposition (CVD). Its extreme hardness makes it effective for working with ferrous metals, ceramics, glass, and stone. Cubic boron nitride (CBN) is the second hardest known material and is synthesized through HPHT processes. It excels in grinding hardened steels, superalloys, and other difficult-to-machine ferrous materials, as it does not react chemically with iron at high temperatures, unlike diamond.

Superabrasives are typically used in bonded forms, such as grinding wheels, honing stones, and cutting tools, where the superabrasive particles are embedded in a matrix (e.g., metal, resin, or ceramic). The selection of a superabrasive depends on the workpiece material and the specific application. Their superior hardness and wear resistance lead to longer tool life, higher material removal rates, and improved surface finishes compared to conventional abrasives.