Mixed high low fretting fatigue of Ti6Al4V: Tests and modelling

In this paper fretting fatigue tests under a combined HCF/LCF loading regime are reported. This loading cycle is representative of operating conditions at the interface of the dovetail fixing between fan and blade in an aeroengine, although a classical geometry was considered, viz. the contact of cylinders against a ground flat tensile specimen. Both, specimen and pads were made of fan blade and disc alloy Ti6Al4V. The main objective of these experiments was to investigate the influence of such complex contact loads on the fretting damage and most importantly on fretting fatigue. A methodology to estimate total life is proposed and assessed against the experimental data. The results show that the main effect on fretting fatigue life is associated with the level of tangential force and that the predictive method was able to capture the effect of the experimental parameters on life, together with the influence of the residual stress field due to shot peening.