Fatigue-induced dislocation structure of titanium alloy VT5-1ct at temperatures of 293-11K

Abstract The dislocation structure formed during the final stage of fatigue at high-- and low-amplitude stresses at T = 293 K in air and T = 293, 93 and 11 K in high vacuum is studied on the Ti alloy VT5-1 ct which has been prepared by two processing methods. The σ - N curves are plotted for corresponding experimental conditions. It is shown that slip alone is responsible for the plastic deformation. The characteristic features of the dislocation structure formed are reported. The morphology of the α phase does not influence the character of the dislocation structure. At lower temperatures, the subtructure remains practically unaltered, although the likelihood of uniformly distributed dislocations is lower. The lifetime is essentially dependent on the environment, temperature and the alloy microstructure, the latter especially important at low temperatures in the high-amplitude region.