Abrasive discs consist of abrasive grains applied to a backing made of cloth, fiber, film, paper, non-woven, or other material. The abrasive grains remove surface materials such as metal, ceramics, glass, plastics, and paint. Consequently, abrasive discs are used in wet and dry grinding, sanding, cleaning, polishing, and surface preparation in a variety of industries, including metalworking, woodworking, ceramics, and semiconductors. A disc’s backing, abrasive grain, grit size, and mounting help determine its applications.

Abrasive discs use several different types of backing. Cloth discs consist of a woven fabric such as cotton and are used in aggressive applications such as abrasive planing. Fiber discs are denser than cloth and contain vulcanized or chemically treated cotton or cellulose fibers; however, fiber discs may curl under humid conditions. Film discs use abrasive grains on plastic film, while foam and sponge discs use abrasive grains bonded onto a foam layer, sponge, felt or other soft, resilient materials. Similarly, metal discs use abrasive grains bonded onto a metal backing such as aluminum or brass. Other types of disc backing include paper, screen, non-woven, or aggregate materials.

Abrasive discs also use several different types of abrasive grains. Aluminum oxide, the most common industrial mineral in use today, is used either individually or with other materials to form ceramic grains. Aluminum oxide is also combined with emery and crocus to produce abrasives suitable for finishing applications. Other types of abrasive grains include garnet, tungsten carbine, silicon carbide, and alumina-zirconia. Super-abrasive diamond pastes are useful in ferrous polishing or lapping applications where heat and reactivity are not a factor. Cubic boron nitride (CBN) is a superabrasive grain with hardness second to diamond and a cubic crystal structure. CBN provides superior grinding performance on carbon and alloy steel.

Grit size measures the abrasive grains in a matrix or bonded to a surface. With abrasive discs, grit sizes are based on ANSI (U.S.), FEPA (European), JIS (Japanese), or Micron graded standards.

Abrasive discs also differ in terms of mounting and special features. For example, hook and loop mounting attaches the abrasive using a hook and loop fabric whereas bore / center mounting uses a central hole for mandrel, arbor, spindle, or shaft mounting. Other types of mounting include quick change and PSA / adhesive. In terms of features, abrasive discs may use an open or closed coat, metal bond, or disc roll. DeLappe and flutter discs have a series of radially cut shifts emanating from the center or around the disc periphery.

Source:

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Equipment/Cutting_Tools/Abrasive_Pads_Discs