MECHANISMS OF FRETTING FATIGUE

Fretting fatigue is one of the most important phenomena for inducing a dramatic reduction of fatigue strength and consequently, of unexpecte d failure accidents. There are numerous works on fretting fatigue. The objective of the present review is to clarify fretting fatigue mechan isms based on the vast amount of research work. A fretting fatigue cra ck is initiated at the highest point of tangential force on a contact surface in the very early stage of fatigue life. The tangential force is the dominant factor in enhancing crack initiation and propagation a nd hence, in reducing fatigue strength. Further studies on short crack and mixed-mode crack growth behavior in fretting fatigue are needed.