Different Types of Bonded Abrasive

Posted by Tom Brady on November 17th, 2022

Bonded abrasives comprise abrasive grains held together in a matrix of glass, rubber, or other binders. They are used to eliminate surface materials such as metal, glass, plastics, and paint. Bonded abrasives are used in grinding wheels and abrasive sticks. Grinding wheels are used in a diversity of applications and industries, while abrasive stones are used for sharpening edges & honing internal or external surfaces.

Types of bonded abrasive

Grinding wheels with bonded abrasive can have numerous shapes. Some wheels are flat or they will have a raised centre with a cone or cylinder which is mounted on a pin or mandrel. The other wheels have a depressed centre, a cup-shaped or bowl-shaped, a tapered body, or a ring shape. The depressed centre wheels are used for metal bars or to remove masonry products. The Cup-shaped wheels can be straight or flared. The recessed, or relieved, wheels may be recessed on one side or both sides.

The Tapered body wheels have a thick cross-section at the bore, which becomes thin or tapers toward the out diameter. To account for the differences, other standards are also used.

Specifications of bonded abrasive

Grit size measures the grains in a matrix or bonded to a surface. Typically, grit sizes are based on ANSI or Micron-graded standards. Coarse grains, remove large amounts of material. Medium grains remove lesser material but provide a better finish than coarse grits. Fine grits are appropriate for light cutting and finishing, while fine grits are used to improve the finish. The bonded abrasive uses several different bond types. Some use electroplated or brazed metal bonds among the abrasive grains or the grains of a metal substrate. Others use a shellac, rubber, or glass bond system between abrasive grains. Lower strength bonds such as silicate diminish heat generation but lack the life & durability of vitrified or resin bonds. Reinforced bonds use a fibre mesh or other fibres or materials to progress the structural integrity of bonded abrasives. Bonded abrasives use numerous different types of abrasive grains. It is used either individually or with additional materials to form ceramic grains. Aluminium oxide is combined with emery & crocus to produce abrasives suitable for final applications.

The Super-abrasive diamond pastes are beneficial in ferrous polishing or lapping applications where heat & reactivity are not a factor. Cubic boron nitride is a super abrasive grain with a hardness second to diamond & a cubic crystal structure, and it provides superior grinding performance on carbon & alloy steel. There are numerous ways to mount bonded abrasives. The hook and loop mounting attaches the abrasive using a hook & loop fabric whereas centre mounting uses a central hole for the mandrel, spindle, or shaft mounting. Additional types of bonded abrasive mounting include quick change.