Fretting fatigue in elastic contacts due to tangential micro-motion

Stress analysis of two elastic bodies in contact, when one of them is subjected to an alternating stress, was carried out in this study. Surface and effective stresses for different values of applied alternating stress were determined within the area of contact. Critical zones where fretting fatigue cracks may initiate were found at the edge of contact where stresses reach a maximum. Displacement distribution due to various types of stresses was determined and was found to increase with increasing the applied alternating stress and the distance from the centre of contact. An expression to predict fatigue failure under fretting conditions was proposed. This expression includes most parameters which contribute to failure, such as: contact pressure, applied stresses, friction coefficient, displacement amplitude and elastic properties of both contacting materials. Initial predictions of the suggested expression provide good correlation with test results, and the expression could thus be adopted as an analytical tool for predicting strength under fretting conditions. Copyright (C) 1996 Elsevier Science Ltd