On the deformation mechanisms and strain rate sensitivity of a metastable β Ti-Nb alloy

The Ti-25Nb-3Zr-3Mo-2Sn (wt.%) alloy deforms primarily by {332) twinning with limited {112} twinning and stress-induced phase transformations. For the Ti-25Nb-3Zr-3Mo-2Sn alloy, the yield stress and strain hardening rate are independent of strain rate. It is found that adiabatic heating induced by high strain rate deformations is insufficient to significantly modify the deformation modes. Also the twinning rate and morphologies of {332) twins are independent of strain rate (1 x 10(-3)-1 x 10(3)s(-1)) within the strain range in our experiments. (C) 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved