Parts in Static Contact with Vibration Fretting

Parts in Static Contact with Vibration (Fretting) (Ref 1) 

If the part is in contact with another engineering component, but with no relative movement, then the main concern will be with corrosion. If the mating part is a dissimilar metal, then galvanic corrosion will be a significant risk (see Chapter 2). 

If the contact also involves vibration or impact motion then fretting, fretting corrosion, or even fretting fatigue must be considered. 

This is the case with splines and couphngs where motion is transmitted from one part to another via a loaded contact and in parts fastened or fitted together where there is a source of external vibration, for example, heat exchangers and bearing housings. Fretting-type failures are also found on chains, pulleys, and wire ropes. 

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