The Annular Bearing Engineering Committee.

Airframe Control Bearings Group of the Society of Automotive Engineers.

The objective of the ACBG is to provide industry experience and state of the art technology for airframe bearings, and issue as appropriate, published documents known as SAE Aerospace Standards (AS), Aerospace Recommended Practices (ARP), Aerospace Information Reports (AIR), and Aerospace Resource Documents (ARD).

Also includes the:
    Plain Bearing Subcommittee
    Rolling Element Bearing Subcommittee

A form of hydrogen embrittlement that may be induced in some metals by acid.

A highly substructured non-equiaxed ferrite. It is formed upon continuous cooling by a mixed diffusion and shear mode of transformation and begins at a temperature slightly higher than the transformation temperature range for upper bainite.

Acicular ferrite is distinguished from bainite in that there is only a small amount of carbide present.

Anti-Friction Bearing Manufacturers Association, a United States trade group formed in 1933. AFBMA later became the ABMA, American Bearing Manufacturers Association.

Material hardening by aging. Usually used after rapid cooling or cold working.

Any change in the properties of a material that occurs at ambient or moderately elevated temperatures after hot working or heat treatment.

Aging does not involve any change in the chemical composition of the metal or alloy.

Air cushion devices that are used to "float" heavy loads on a thin film of air.

American Iron and Steel Institute, a standards organization.

See SAE Steel Identification System.

Also known as Full Annealing

A type of heat treatment, often used to soften a material.

Annealing involves heating material to a specific temperature, holding it at that temperature for a known length of time, then cooling slowly to room temperature.

Other than softening, annealing is also used to produce desired changes in other properties and microstructure of a material. Annealing often improves machinability and improves dimensional stability.

When used only for the relief of stress, the process is properly called stress relieving or stress-relief annealing.

In a rolling element bearing, the space between the inner and outer raceways.

The process of using anodic oxidation to form a protective conversion coating on a metal surface; most frequently applied to aluminum.

American National Standards Institute, a standards organization.

A hard plating applied to bearings for wear resistance and corrosion protection. The hardness is approximately 72 on the Rockwell C scale.

Named for British metallurgist Sir William Chandler Roberts-Austen (1843-1902).

Term used to describe the face-centered cubic crystal structure (FCC) of ferrous metals. Ordinary iron and steel has this structure at elevated temperatures. Certain stainless steels (300 series) have this structure at room temperature.

The breakdown of steel's ferrite and cementite structure which allows it to absorb more carbon from the atmosphere, a process which occurs during heat treatment. See also bainite.

When the raw machined races are heated above the transformation temperature (around 720 C) and held there, the the basic metallurgical structure of the steel changes. At that temperature, the steel's ferrite and cementite structure breaks down. Its grain and crystalline structure changes into an austenite and it absorbs more carbon from the atmosphere. The longer the parts are held at temperature, the larger the grain size and the harder they become. Also, the larger the parts, the more difficult it is to maintain continuity throughout.

Partial austeniting occurs below the transformation temperature; full austeniting occurs above the transformation temperature.

The amount a bearing's inner race is able to move perpendicular to the outer race and perpendicular to the direction of rotation.