Application of thermohydrogen processing to Ti6Al4V alloy blade isothermal forging

Application of thermohydrogen processing to Ti6Al4V alloy blade isothermal forging is researched in this paper. The basic properties relating to hot workability of unhydrogenated and hydrogenated with 0.25 wt%H Ti6Al4V alloys are investigated. Isothermal compression tests are used for getting the stress-strain relationship under different forming temperature, and the mechanism of hydrogenation inducing Ti6Al4V alloy softening is researched. The billet shape is optimized by DEFORM-3D software, then force and flow condition are analyzed in the isothermal forging process. The results show that the qualified blades can be forged under the isothermal forging conditions of 0.1 mm/s, 1223 K for unhydrogenated alloy and 1123 K for hydrogenated alloy. After vacuum heat treatment at 973 K for 4 h, the experiment's results of mechanical properties show that thermohydrogen processing improves the mechanical properties of the blade at both room and high temperature.