Patented high-lead and high-tin alloys used to reduce friction in plain bearings.

See also austeniting.

Named for American chemist A.C. Bain, who with Grossman discovered the structure as employees of United States Steel Laboratories.

A metastable aggregate of ferrite and metal carbide / cementite. Bainite results from austenite transformation at temperatures above martensite but below pearlite. It is a stronger structure than stnadard quenched and tempered processes can produce.

Upper temperature range bainite has a feathery appearance; lower temperature range bainite resembles tempered martensite.

Generally, any rolling element bearing which uses balls as the friction reducing elements.

There are three general types of ball bearings, reflecting the direction of the load the bearing is designed to carry: radial, thrust, and angular contact.

A linear motion bearing where the inner race is helical.

Each ball screw assembly consists of a screw with a precision ground or rolled helical groove, a nut (the outer race) with an internal groove, and a circuit of precision steel balls that recirculate in the grooves between the screw and nut. This anti-friction design converts torque to thrust as either the screw or nut turns and the other component moves in a linear direction.

Named for Heinrich Barkhausen (1881-1956), German professor who predicted the phenomenon of small magnetization "jumps" between Weiss domains in magnetized ferrous materials. These jumps are due to domain walls being pinned and released from microstructural obstacles such as grain boundaries and inclusions.

In 1919, Professor Barkhausen induced and detected the shocks or jumps, feeding the energy to a loudspeaker. The resulting noise was nicknamed Barkhausen Noise.

Also known as magnetoelastic analysis or micromagnetic analysis.
A nondestructive testing and measurement process for ferrous products, accurate to 10^-8 cm³.

BNA measures the sample's Barkhausen Noise and maps the microstructural changes. In the bearing industry, BNA is used to determine case depth, pinpoint metal fatigue, identify grinding abuse, generate stress profiles and identify other material attributes.

Any device designed to reduce friction, also designed to constrain motion of mechanical devices along one or more axes.

Rolling element bearings generally have three components: an inner race, an outer race (or housing) and rolling elements.

Plain bearings and bushings generally are one-piece units where the rotating element rides directly against the bearing surface or is separated from the bearing surface by an oil or grease film.

Arguably, every mechanical device contains at least one bearing.

Calculations involving the dimensions, rolling element location and speed, pitch circle, and inner and outer race speeds.
Bearing Frequency Calculations normally involve four fundamental frequencies:
BPFI - Ball/Roller Pass Frequency Inner Race
BPFO - Ball/Roller Pass Frequency Outer Race
BSF  - Ball/Roller Spin Frequency
FTF  - Fundamental Train Frequency
FTFI - Fundamental Train Frequency Inner Race
FTFO - Fundamental Train Frequency Outer Race
The results are calculated as either vibrations per second (Hertz) or revolutions per minute (RPM).
Those values are also referred to as bearing damage pulse frequencies because they describe the primary factors influencing in-service lifespan.
In addition, the frequency calculation process usually involves calculating a number of harmonics.

A black metal finish produced by immersing the item in hot oxidizing salts or salt solutions.

Swedish engineer; developer of the Brinell hardness test and equipment.

Brinell was chief engineer of the Swedish Ironmasters Association; he first showed his test and equipment at the Paris Exhibition in 1900.

The measure of a material's resistance to indentation from a standard hard steel ball, normally 10mm diameter. The size of the ball may vary, and the test load applied varies by material, from 300kg to 3000kg. The load is held for 10 to 30 seconds, again depending on the material being tested.

When the load is removed, the diameter of the indentation is measured. The BHN is calculated from that and expressed as kilograms per square millimeter.

Higher BHN numbers refer to higher indentation resistance. The standard BHN test for materials is American Society for Testing and Materials (ASTM) E-10. ASTM numbers can be converted to approximate Rockwell, Vickers and Mohs hardness numbers.

The indentation of inner or outer race material caused by the rolling elements.

There are two types of brinelling, true brinelling and false brinelling. True is due to material deformation under excessive operating pressure, false is wear-related or vibration-related.

The indentation of inner or outer race material caused by the rolling elements.

True brinelling is the indentation of a part and the movement of material due to excessive operating pressure, impact, dropping or hammering. True brinelling is a material deformation issue where the inner or outer race material has been pushed or squashed out of place.

The indentation of inner or outer race material caused by the rolling elements.

False brinelling is the indentation of a part where the indented material has been worn away. False brinelling is a wear issue due to metal-to-metal contact and is most often caused by external vibration. False brinelling can also be caused by vibration of a stationary bearing, especially in the absence of proper lubrication.