Two dimensional versus three dimensional modelling in fretting fatigue life prediction

Abstract

This work analyses the influence that the type of geometry used to model a cylindrical contact has on fretting fatigue life predictions. It also studies the effect that the assumed fatigue crack shape has on fretting fatigue life predictions. The strain–stress fields are obtained using different finite elements models. These models consider the following three types of behaviour: plane stress, plane strain (2D geometries) and 3D. Each of these models produces a different crack-initiation life, a different evolution of the stress intensity factor (SIF), and therefore a different crack-propagation life. As a consequence, different fretting fatigue life predictions are obtained with each model. Regarding the SIF evaluation, the weight function method is employed in all the models. Finally, the lives obtained using the three numerical models are compared with experimental lives.