The investigation of the steady stage of steel fretting

The effects of slip length, frequency, surface pressure and shape of the longitudinal oscillatory motion on the fretting wear of steel were investigated by a specially designed fretting apparatus using an M.T.S. closed loop axial hydraulic testing system.

The rate of fretting wear in the steady stage was found to increase with increasing slip length and specific surface pressure and to decrease with increasing cyclic frequency and material hardness. The wave shape of the oscillatory motion does not appear to affect the wear rate.

Increased slip, greater surface pressure and lower cycling frequency all promote the adhesion mechanism of fretting. With higher frequencies decreased slip and low surface pressures, the product of fretting wear is mainly oxides and oxidation is the leading wear mechanism.