Also Retainer.

The device used to space, separate and retain the balls or rollers of a rolling element bearing. Cages are most often constructed from steel, plastic or brass.

The process of making an iron or steel product more resistant to oxidation.

Calorizing involves heating the item in aluminum powder at 800 to 1000 ºC (1470 to 1830 ºF).

The tendency of a metal at high temperatures to absorb and diffuse carbon atoms throughout its structure. The additional carbon may remain dissolved or form metal carbides.

Carburization is a variety of case hardening which produces a carbon gradient extending inward from the surface. This enables the surface layer to be hardened either by quenching directly from the carburizing temperature or by cooling to room temperature then reaustenitizing and quenching.

The cross-sectional depth in a material to which a hardness of Rc 58 (58 on the Rockwell C Scale) is maintained.

See also through hardening.

A generic term for hardening a material, specified to a specific cross-sectional depth.

The hardening processes most commonly used are carburizing, cyaniding, nitrifying and carbonitriding. Generally, those specific terms are used rather than case hardening.

Any coating deposited on a metal surface by a high-temperature diffusion process. Examples are carburization, calorizing, and cromizing.

Also known as iron carbide.

An Fe3C iron/carbon compound. When it occurs as a phase state in steel, the chemical composition will be altered by the presence of manganese and other carbide-forming elements.

A grease formulated so that rolling elements can create a permanent path through it. On subsequent orbits, the rolling elements glide on the film of oil that exudes from the thickener.

Because the thickener does not have to be continually displaced, channeling greases reduce torque, friction and thermal energy within the bearing, which extends bearing life.

A high-temperature metal surface treatment. A surface alloy is formed by the inward diffusion of chromium.

See also Hot Working.

Metalforming, normally at room temperature, under low strain and temperature conditions which induce strain hardening.

The most common type of ball bearing. See also Conrad Method

A Conrad ball bearing is a nonseparable deep-groove ball bearing, with symmetrical inner and outer raceways. Because of its deep grooves (or raceways), Conrad style ball bearings can be used for radial loads, as well as thrust loads from either direction.

A method for assembling single row ball bearings. Named for Robert Conrad, holder of 1903 British patent 12,206 and 1906 U.S. patent 822,723 covering this particular bearing assembly method.

In the Conrad Method, the inner race and outer race are placed together, the inner inside the outer and touching it at some point. The open space inside the bearing components is in the shape of a cresecent. The bearing balls are then placed into this crescent-shaped space. The inner race is then "snapped" toward the balls and concentric with the outer race. The balls are then evenly distributed around the raceways, ready for the insertion of the retainer.

A drawback of the Conrad Method is that only a limited number of balls can be inserted, limiting the radial load capacity.

The chemical or electrochemical reaction between a material, usually a metal, and its environment that produces a deterioration of the material and its properties.

The corrosive loss of a metal's ductility. Corrosion embrittlement is often intergranular and cannot be determined by visual inspection.

Embrittlement under creep conditions that results in abnormally low rupture ductility; failure occurs by intergranular cracking. In most steel alloys, it is related to the level of impurities or inclusions.