Analysis of deformation mechanisms operating under fatigue and dwell-fatigue loadings in an α/β titanium alloy

This paper investigates the deformation processes operating in a grains of Ti-6Al-4V submitted to fatigue and dwell-fatigue loadings at room temperature. With this aim, mechanical tests were interrupted after a given number of cycles or cumulated plastic strain. Slip traces analysis combined with electron back-scattered diffraction enabled to evidence the operation of < a > and < c + a > slip, twinning and interface sliding. The main parameters controlling their activity were analyzed, in particular regarding the crystallographic orientation and the load hold duration. Based on this statistically sound investigation, the differences between fatigue and dwell-fatigue behaviors are finally discussed.