Effects of heat treatment process on microstructure and mechanical properties of TC4-DT titanium alloy plate

Effects of heat treatment on microstructure and mechanical properties of TC4-DT titanium alloy plate were investigated.The results show that the primary α-phase increases,strength decreases and ductility increases with the solution temperature decreasing when the TC4-DT alloy is heated in the α+β phase region.Moreover,the slower the cooling rate,the less α′ phase will be acquired and the hardening effect will be decreased.With the aging temperature and aging time increasing,the amount of precipitated secondary α phase increases and grain coarsens,the yield strength increases first and then decreases,but the ductility changes a little.Therefore,the best heat treatment process of TC4-DT alloy may be 955 ℃×1 h,AC+550 ℃×8 h,AC,under which the alloy will get excellent comprehensive mechanical properties.