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Fretting-corrosion is a combined damage
mechanism involving corrosion at points where two moving metal
surfaces make rubbing contact. It occurs essentially when the interface
is subjected to vibrations (repeated relative movement of the two
contacting surfaces) and to compressive loads. The amplitude of
the relative movement is very small, typically of the order of
a few microns. When the frictional movement in a corrosive medium
is continuous, the resulting process is termed tribocorrosion.
Means of preventing fretting corrosion :
- lubrication with oils or greases, to reduce
friction and exclude oxygen from the interface.
- Increase in the hardness of one or both
materials in contact. Certains material combinations show better
friction behaviour than
others. Surface hardening treatments can be beneficial.
- Use of seals to absorb vibrations and exclude
oxygen and/or moisture.
- Reduction of the friction loads in certain
cases, or on the contrary, increase of the friction loads to
attenuate vibrations.
- Modification of the amplitude of the relative
movement between the two contacting surfaces.
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