Fretting fatigue strength properties of pearlitic and bainitic steels with medium carbon steel contact material

Abstract

The fretting fatigue properties of pearlitic and bainitic steel with medium carbon steel contact material were examined using the clamping contact double bridge pads system. In order to investigate the effects of contact pressure and relative slip amplitude on fretting fatigue strength, the fretting fatigue tests were carried out under the conditions of two contact pressures and three pad lengths. The fretting fatigue strength decreased with increasing contact pressure and with increasing pad length at the constant contact pressure of 98MPa. Also crack initiating position moved from the edge to the center of fretted damage surface with decreasing contact pressure. Interrupted fretting fatigue tests were carried out in order to investigate the fretting damage and the crack initiation at the pad length of 30mm and the contact pressures of 49, 98 and 196MPa. The saturation of fretting damage occurred beyond a certain number of fretting cycles, and the ratio of number of cycles to saturation of fretting damage was about 50 to 60% in the present conditions. And the ratio of number of cycles to crack initiation was less than 20% in this study.