Effect of hydrogenation on the high temperature deformation behavior of Ti-6Al-4V alloy with lamellar starting structure

Effect of 0.27 wt% hydrogen addition on the high temperature deformation behavior in the temperature range 760-0 of Ti-6Al-4V alloy with lamellar starting structure was investigated. By means of OM and XRD, microstructures of the Ti-6Al-4V alloy both with and without hydrogen content of 0.27wt% were obtained. The flow stress of the hydrogenated Ti-6Al-4V alloy with hydrogen content of 0.27wt% was lower than that of the as received Ti-6Al-4V alloy at deformation temperatures below 920 and higher than that of the as received Ti-6Al-4V alloy at 960 and above. The decreasing in flow stress at lower deformation temperatures ( <=920) may be attribute to the increasing of the more ductile β phase and the increasing in flow stress at deformation temperatures higher than 960 was mainly due to the solid solution strengthening by hydrogenation.