The progressive quality or phenomenon of materials which leads them to fracture under repeated or fluctuating stresses when individually, those stresses are within the material's tensile strength.

The maximum stress that a material can sustain for a specified (or standardized) number of stress cycles before it fails.

The Federation of European Bearing Manufacturers' Association.

FEBMA is a federation of bearing associations in Austria, France, Germany, Italy, Spain, Sweden, and the UK. It represents the interests of the European bearing industry.

Also known as a notch or loading groove.

In a full-compliment ball bearing or heavy duty ball bearing, a filling notch may be cut into the inner race to allow the final few balls to be loaded during assembly.

The filling notch is designed such that it allows the balls to be loaded into the bearing but does not cut into the inner race where the balls will roll during normal operation.

Type of non-contact bearing which rides on a thin film of lubricant.

Hydrodynamic bearings were first observed by Pauli in 1849 and Hirn in 1854.

In 1883, Nikilay Petroff first determined that the action at work in a fluid film bearing was hydrodynamic, and developed the power loss calculations which have defined his position in the bearing industry. In 1886, Reynolds developed the differential equation defining the pressure created in a hydrodynamic bearing. In the late 20th century, Reynolds' equations were modified for accurate computer modeling and to reflect the development and application of new types of lubricants.

The nickname of the 4-8-4 steam freight locomotive, number TRBX 1111, commissioned from American Locomotive by The Timken Company in 1930 to prove the advantages of roller bearings over plain bearings. Timken chose the 4-8-4 configuration as the most flexible for both fast freight and passenger service. Also, that configuration could be used on virtually any main line at any reasonable speed.

This was a landmark application, the first locomotive built with all roller bearings, and brought roller bearings to the attention of the rail industry for the first time in a meaningful way.

Beginning with the New York Central, TRBX 1111 was loaned to 14 railroads to prove Timken bearings. During the demonstration period, it pulled 328 freight trains and 227 passenger trains, "without incident."

1111's most memorable moments were publicity stunts. The Pennsylvania Railroad had three men pull the locomotive back and forth on the track with a rope; later in Chicago, three women did it.

After covering 89,000 trouble-free miles in two years, 1111 was with Northern Pacific Railroad when it suffered fire box crown sheet damage from low water and/or poor coal quality. NP agreed to buy the locomotive but Timken had to pay for repairs. NP bought Four Aces in 1933, renumbered 2626, and ran it continuously until retirement in 1955. Four Aces' last run was a special excursion in 1957; it was scrapped that fall and NP was all-diesel by January 1958. Timken keeps the Four Aces bell on display in its corporate lobby; a model is in the City of Canton Community Time Capsule.

See also Combined Carbon.

In steel or cast iron, free carbon is that portion of the total carbon content that is present in elemental form as graphite or temper carbon.

Uneven wear patterns found on bearing races due to cycles of sliding or skidding by the rolling elements.

Generally, the relative motion which creates fretting is very small amplitude. Fretting often gives rise to corrosion within the bearing, caused by the fine wear debris.

A type of rolling element bearing which has the maximum possible number of rolling elements installed. Achieved by eliminating the cage or retainer. A filling slot must also be machined into the inner race to facilitate loading the rolling elements. Full-complement bearings have higher load ratings but generally sacrifice speed capacity due to the elimination of the cage or retainer.