Grease

Grease

The ASTM definition of lubricating grease is: “A solid or semi-solid lubricant consisting of a thickener agent in a liquid lubricant. Other ingredients imparting special properties may be included” A commercial lubricating grease usually consists […]

Elastic Deformation

Elastic Deformation

Definition Elastic deformation is a change of the shape of the body as a reaction to applied stress. This deformation is only temporary and once the stress is released, the undeformed shape of the body […]

tribometer

Tribometers

Tribometers are the devices used to analyze and characterize tribological systems. The most common direct measurement is the measurement of friction coefficient (and shear strength). During the post processing stage other quantities can be measured, […]

Friction Coefficient

Coefficient of Friction

Friction is a force resisting relative motion and may occur at the interface between the bodies, but may also occur within the bodies. The concept of friction coefficient was first formulated by Leonardo da Vinci […]

Fatigue Surface Crack

Rolling Contact Fatigue

Rolling-contact fatigue (RCF) is defined as a failure or material removal driven by crack propagation caused by the near-surface alternating stress field.  It is typically considered that if a bearing is properly mounted, aligned, lubricated, […]

Fatigue Wear

Fatigue Wear

Fatigue wear is a type of wear where a number of cycles is needed to generate debris. The fatigue process in metals may induce the generation of surface and subsurface cracks, which after a critical […]