abrasives

An abrasive is a material capable of scratching or wearing away another material because of its hardness, used to shape, finish, or remove material. Abrasives are employed in a range of operations from cutting and grinding to polishing and deburring, and include both natural minerals and synthetic compounds.

Abrasives are typically categorized by form: bonded abrasives such as grinding wheels, segments, and discs; coated abrasives such as sandpapers, belts, and sheets; and loose abrasives used in blasting and tumbling. These forms determine how the abrasive interacts with the workpiece and the type of finishing action produced.

Common abrasive materials include natural emery or garnet, and synthetic materials such as aluminum oxide, silicon carbide, boron carbide, and superabrasives like diamond and cubic boron nitride. Their hardness, toughness, and friability determine cutting action and surface finish, with different materials suited to metals, stone, ceramics, and composites.

Performance is influenced by grain size, hardness, bond, and the working environment. Grit size indicates removal rate and finish; finer grits yield smoother surfaces. Bonds can be vitrified, resin, metal, or rubber, affecting wheel strength and wear. Standards from bodies such as FEPA and ANSI classify grit and grade to guide selection.

Abrasive processes generate heat and dust, so cooling or lubrication is often required, and proper personal protective equipment is essential. The selection of an abrasive balances material removal, surface quality, tool life, and safety considerations.