Deformation analysis of crystal plasticity and texture prediction of Zr-4 alloy during cold rolling process

Abstract:

A cold rolled Zr-4 alloy sheet of 3.6mm thickness with a typical bimodal texture was applied. Texture evolution was characterized by electron backscattering diffraction (EBSD) technique. Visco-plastic self-consistent (VPSC) model was analyzed to evaluate deformation mechanism of Zr-4 alloy sheet during cold rolling. Effects of rolling pass number, reduction per pass and total deformation on texture were predicted with the VPSC model. Results show that the texture of Zr-4 alloy sheet maintained a typical basal bimodal texture during the cold rolling process. Rolling pass number and reduction per pass had little influence on the texture evolution and deformation mechanism. However, total rolling deformation had significant effect on the texture evolution. With the decrease of deformation, the C-axis of most grains rotated from the normal direction to the transverse direction; When the rolling deformation is less than the critical deformation which is 39%, the Kearn factors of normal direction (Fn) rises rapidly with the increased deformation, and prismatic slip quickly decreases.When the deformation exceeds 39%, only slight increase of Kearns factor was observed, and prismatic slip becomes stable.

Key words:Zircaloy-4;cold rolling;texture;VPSC