The influence of grain orientation on the fretting fatigue behaviour in aluminium alloys

Abstract

Fretting fatigue is a highly damaging failure mode, yet its strong performance scatter poses a major challenge for accurate prediction, with microstructural characteristics, especially grain orientation, being a key intrinsic factor. This study investigates how grain orientation affects fretting fatigue behaviour and drives performance scatter. Using the crystal plasticity finite element method (CPFEM), a fretting fatigue model incorporating microstructural characteristics was developed. By comparing simulation results of textured and randomly oriented grains, it is found that grains with different orientations exhibit varying deformation capacities, leading to stress–strain redistribution, as well as stress concentration and elevated stress triaxiality near grain boundaries. Further analysis demonstrates that wider grain orientation distributions produce greater scatter in response, indicating that random orientations are a major intrinsic source of fretting fatigue variability. The present work captures the stochastic effects induced by random grain orientations under fretting fatigue contact. The findings provide micro‑mechanical insights into the relationship between microscopic plastic deformation mechanisms and the statistical characteristics of fretting fatigue behaviour.