On the damage mechanisms during compressive dwell-fatigue of β-annealed Ti-6242S alloy

Abstract The present study contends with unveiling the damage mechanisms during compressive dwell-fatigue of β-annealed Ti-6242S alloy. The shearing/displacement of lamellar phases, stacking fault nodes formation, and formation of coarse grains (under the lower stress level) are identified as key factors influencing crack initiation and propagation which mainly contribute in fatigue performance deterioration. Such phenomenal evolutions are interconnected with the microstructure evolution, i.e. globularization and grain refinement of lamellar phases, which can be justified considering the dwell time at maximum applied load by providing a proper condition for (i) activation of multiple slip systems, and (ii) dislocation cross-slip, and substructure development.