Effect of heat treatment on microstructure and mechanical properties of Ti62421s high temperature titanium alloy

The effect of solution temperature and aging temperature on the microstructure and mechanical properties of Ti62421s high temperature titanium alloy were studied. The results show that, the content of primary α-phase decreases and the content of transformed β phase increases with increasing solution temperature when the alloy is treated in α + β field, only weave transformed β-phase exists when the alloy is treated in β field. With the aging temperature increasing, primary α-phase size grows up. With increasing solution temperature and aging temperature, only the content of aluminum increases in the transformed β-phase, where as the contents of other alloying elements decrease. With the solution temperature rising, and the strength and area reduction rate increase firstly and then decrease rapidly, the elongation decreases. The heat treatment of (980°C, 1 h, AC)+(550°C, 8 h, AC)for this alloy is preferable for optimum mechanical properties, and the tensile strength, elongation and area reduction rate of the alloy are 1 077.04 MPa, 13.6%, 26.02%, respectively.