Effect of hydrogenation on the hot deformation of Ti-6Al-4V alloy

Hot deformation of hydrogenated Ti-6Al-4V alloy has been carried out with the Hot-simulator of Gleeble-1500D. The microstructures of hydrogenated alloys have been investigated by XRD and OM. Activation energies of the alloys with different hydrogen content have been calculated. The results show that with the increase in hydrogen content, the fraction of β phase increases and the flow stress at high temperature decreases obviously, whose change presents a sunken curve, i.e. after reaching a minimum then increases at a particular processing temperature. The hydrogen content corresponds to the minimum in stress decreases when the temperature is increased. The deformation temperature can decrease 50°C or strain rate enhance a order of magnitude in proper hydrogenated at a constant stress. The activation energy decreases with the increase of hydrogen content, and different deformation mechanisms are exhibited.