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Adhesive wear

When two metal surfaces come into contact with each other, they initially touch only at a few rough points. Friction and wear originate at these points. When a compressive load is applied, these rough points are plastically deformed and finally welded together because of the high pressure that is created. As sliding continues, these bonds are broken, producing cavities on one surface and depressions on the second surface. Abrasive particles detach and rub against the surface, contributing to wear.

There are several types of adhesive wear:

  • Sliding wear - when one solid slides over another other solid
  • Galling wear - intense form of adhesive wear
  • Scoring / scuffing wear - formation of grooves and scratches in the sliding direction
  • Oxidative wear - wear in unlubricated ferrous systems

Adhesive wear can cause problems such as:

  • Cold welding
  • Scoring
  • Pits
  • Seizing
  • Built-up edges
  • Scuffing
  • Tool breakage

The following measures can be taken to prevent adhesive wear:

  • Selecting softer materials
  • Increasing the hardness of the material
  • Selecting highly incompatible pairs, such as silver on cobalt
  • Selecting materials having low surface energy