Strength-ductility trade-off deviation in a pre-deformed metastable β titanium alloy.

In the present study, pre-deformation was applied to a metastable β titanium alloy (Ti-36Nb-2Ta-3Zr-0.35O) with the hope of improving its overall mechanical properties. The microstructural evolution and mechanical properties of the as-rolled alloys with different thickness reductions (from 4% to 35%) were characterized and analyzed. The results show that increasing the amount of pre-deformation can increase the strength (yield strength and tensile strength) of the Ti-36Nb-2Ta-3Zr-0.35O alloy without (4%–15% pre-deformation) or with only minor (23%–35% pre-deformation) sacrifice of ductility. Due to the increase of pre-deformation reduction, the β phase stability increases, leading to the twinning activities and the evolution of twinning system, which contribute to the strain hardening and the good ductility of the alloy pre-deformed by 9% and 15%. [ABSTRACT FROM AUTHOR]