Deformation behavior in the isothermal compression of hydrogenated Ti-6Al-4V alloy

Effect of hydrogen on deformation behavior of the Ti-6Al-4V alloy was investigated through isothermal compression. Addition of hydrogen decreases significantly flow stress, improves strain rate of more than one order of magnitude and decreases significantly deformation temperature of the Ti-6Al-4V alloy. The minimum flow stress of Ti-6Al-4V alloy is at a hydrogen content of 0.4wt% in the deformation temperature range from 760°C to 800°C, but the minimum flow stress is at a hydrogen content of 0.2wt% in the deformation temperature range from 840°C to 920°C. Meanwhile, apparent activation energy for deformation of the Ti-6Al-4V alloy is 208.3 kJ/mol at a hydrogen content of 0.4wt% in α+β two-phase field, decreasing 316 kJ/mol in comparison with that of the Ti-6Al-4V alloy with natural hydrogen.