A review of analytical aspects of fretting fatigue, with extension to damage parameters, and application to dovetail joints

Recent advances by the authors in analytical methods for the analysis of plane fretting fatigue (FF) contact problems are described, acid new consequences for FF damage are derived. Constant normal load and oscillating tangential load (the celebrated Cattaneo-Mindlin case) are considered with in-phase oscillating moderate bulk stresses, for an arbitrary spline rotated geometry and, in particular, the flat punch with rounded corners in view of application to the dovetail joints. Extremely simple, new results are found for initiation parameters such as tangential microslip and frictional energy, which have been used under certain conditions as threshold parameters for FF. Finally, it is shown that for an "almost flat" geometry, the surface damage parameters decrease, but the tensile stress concentration increases, although it becomes more localized, suggesting that for cracks eventually initiated, the likelihood of self-arrest is higher than in the equivalent Hertzian case with same loads. This seems to interpret recent experiments, although it is not clear whether the optimal geometry in terms of FF life is the perfectly hat one, or an intermediate one. (C) 2001 Elsevier Science Ltd. All rights reserved.