Wear

For other uses, see Wear (disambiguation).

In materials science, wear is the erosion of material from a solid surface by the action of another solid. The study of the processes of wear is part of the discipline of tribology.

There are four principal wear processes:

1. Adhesive wear
2. Abrasive wear
3. Corrosive wear
4. Surface fatigue

Adhesive wear

Adhesive wear is also known as scoring, galling, or seizing-occurs when two solid surfaces slide over one another under pressure. Surface projections, or asperities, are plastcally deformed and eventually welded together by the high local pressure. As sliding continues, these bonds are broken, producing cavities on the surface, projections on the second surface, and frequently tiny, abrasive Particles- all of which contribute to future wear of surfaces.

Abrasive wear

When material is removed by contact with hard particles, abrasive wear occurs. The particles either may be present at the surface of a second material or may exist as loose particles between two surfaces. Abrasive wear can be measured as loss of mass by the Taber Abrasion Test according to ISO 9352 or ASTM D 1044.

Corrosive wear

Main article: Corrosion

For often referred to simply as "corrosion", corrosive wear is deterioration of useful properties in a material due to reactions with its environment.

Surface fatigue

Main article: Fatigue (material)

Surface fatigue is a process by which the surface of a material is weakened by cyclic loading, which is one type of general material fatigue.

See also

• Rheology