Investigation on high temperature compression behaviour of hydrogenated Ti6Al4V alloy

Abstract

Isothermal compression of hydrogenated Ti6Al4V alloy was carried out on a Gleeble-1500D simulation tester at the strain rate 3×10⁻³ s⁻¹ and high temperatures. Before the isothermal compression, a simplified thermohydrogen processing (THP) was used for Ti6Al4V. Attention was paid to the effect of THP on subsequent compression behaviour. The results show that hydrogen can effectively lower the flow stress and deformation temperature and enhance the strain rate sensitivity index (m value) for isothermal compression. The increasing amount of β phase and the ultrafine and equiaxial microstructure precipitated between the original α or β laths are the main reasons for the simplified THP to improve the formability of Ti6Al4V.