Design and optimization of the processing parameters of Ti-5Al-3V-3Zr-0.7Cr titanium alloy as a candidate material for pressure hull of fusion reactor

Ti-5331 titanium alloy, a new near α titanium alloy, as a candidate material for pressure hull of fusion reactor was studied in details in this paper. Firstly, the flow behavior was analyzed by stress-strain curves obtained by isothermal compression of Ti-5331 alloy, and the constitutive model was developed in the form of the hyperbolic sine. Secondly, the effects of deformation parameters on spheroidization mechanism were discussed. Finally, based on the dynamic materials model and instability criterion, the power dissipation map and instability map were constructed at the strain of 0.6, the obtained optimal processing parameters of Ti-5331 alloy were 750°C/0.001–0.01 s−1 and 850–900 °C/0.01–0.1 s−1 with the peak efficiencies of 65% and 73% respectively, which were further verified by the plate rolling test of Ti-5331 alloy.