Competition between Phase Transformation and Deformation Twinning in Pure Zr and Zr-Ti Alloys Subject to Rolling

Abstract

The effects of temperature and Ti content on the deformation mechanisms of pure Zr and Zr-Ti alloys were investigated. The results indicate the existence of a competition between deformation-induced phase transformation from a hexagonal close-packed structure to a face-centered cubic structure and deformation twinning. The phase transformation was suppressed while the {101 1} compressive twinning was promoted with increasing the rolling temperature and/or Ti content. This can be attributed to the activation of basal dislocations at high temperature and the increased stacking fault energy with Ti content.