Dynamic recrystallization behavior of Gd-containing Mg alloy under torsion deformation

Abstract

The thermal deformation behavior of Mg-11.95Gd-4.5Y-2Zn-0.37Zr alloy was investigated by torsion tests under different deformation conditions. Electron backscattered diffraction (EBSD) technique was used to study the effect of deformation temperature and strain rate on the dynamic recrystallization grain (DRX) and texture evolution during torsion deformation. The results indicate that the equivalent stress-strain curve of the alloy under hot torsion is similar to the curve under thermal compression. A predictive model for the critical strain (εc) and the Z parameter of the investigated Mg-alloy during torsion deformation has been established. The influence of deformation temperature on the DRX and grain size distribution is significantly different in different temperature regimes. We have observed that the grain size distribution is significantly wider at higher temperatures. Moreover, the distribution of pole density is relatively uniform under different torsion deformation conditions. The torsion has significantly declined the texture and the maximum texture intensity decreased with the decrease in grain size under different deformation conditions.