Effect of hydrogen on the deformation development in the titanium alloy with a hierarchical ultrafine-grained structure in the temperature range of 293–973 K

Hydrogen effect on the deformation behaviour of the ultrafine-grained titanium alloy (VT16 grade) is studied at the temperature interval (293–973) K. Hydrogenation to the concentration of 0.3 wt % is found to lead to an increase in the values of uniform deformation and total deformation to failure at temperatures 293–573 K. In the range of higher temperatures (673–973) K, hydrogen presence reduces the resistance of the ultrafine-grained VT16 alloy to the localization of deformation at the macro-level and value of deformation to failure. Possible reasons for the increase in the transition temperature of the ultrafine-grained VT16 alloy to the superplastic state and the decrease in the temperature interval of the manifestation of its superplastic properties in the presence of hydrogen in a solid solution are discussed.