AirbusLTDS, Ecole Centrale de Lyon, ToulouseEcully,
LTDS, Ecole Centrale de Lyon, Ecully,
EADS IW-Computational Structural Mechanics, Toulouse Cedex 03,
Pages: 25 Published: Jan 2011
Although fatigue limits of smooth specimens under various complex loadings have been determined, few models have been proposed to predict well-known experimental results such as size effects and stress gradient effects. This paper addresses the stress gradient effect issue. A new non local multiaxial fatigue approach is proposed and applied to rotating bending and fretting experiments. The proposal takes as a starting point the rotating bending results and stress gradient analysis of a cylinder-plane contact in partial slip sliding regime. Both weight function and “process volume,” used to compute the mean value of the weight function, are introduced in a phenomenological way. The weight function reflects the experimental trend of fatigue limit under rotating bending whereas the connected process volume allows dealing with special stress gradient induced by cylinder-plane contact under partial slip. The proposal shows good capabilities to predict four-point rotating bending fatigue limit and crack initiation of a similar Inconel 718 cylinder/plane contact under partial slip regime.
multiaxial fatigue, fretting, stress gradient, Inconel 718
Paper ID: STP49300S