Mechanisms of plastic deformation of zirconium-based alloys upon uniaxial compression under different temperature-rate conditions

Based on the results of X-ray diffraction analysis of texture of the Zr-1% Nb and Zr-2.5% Nb model alloys compressed uniaxially at temperature corresponding to the β and α + β fields of the phase diagram, the mechanisms responsible for plastic deformation have been determined. These are the crystallographic slip in the β-Zr and α-Zr grains and also the diffusional mechanism of mutual displacement of crystallites along interphase boundaries, which is activated upon the α β phase transformations and is the basis of superplasticity. The contribution of each mechanism to the formation of specimen texture depends on the temperature-rate regime of compression.[PUBLICATION ABSTRACT]