Microstructure and texture of coarse-grained Mg-Gd-Y-Nd-Zr alloy after hot compression

The microstructure and texture evolution of coarse-grained Mg-Gd-Y-Nd-Zr alloy during hot compression were studied by electron backscattering diffraction (EBSD) analysis. Dynamic recrystallization (DRX) mechanism and effects of DRX and dynamic precipitation on the texture evolution were discussed. The results show that flow curve has typical characteristics of dynamic recrystallization. Grain boundaries start to serrate at the early stages of deformation, and then DRX grains are formed by the in situ evolution of the subgrains with the growth of low angle boundaries to high angle grain boundaries. When the strain increases to 1.61, the volume fraction of recrystallized grains increases to 71% and the average grain size reduces to 27.2 mu m. During the compression process, the second phase particles precipitate along the DRX grain boundaries and play an important role in grain refinement. The {0001} plane of unDRX area is rotated gradually to be perpendicular to the compression direction. The final texture is weakened due to the cooperative effect of dynamic recrystallization and dynamic precipitation. (C) 2012 Elsevier Ltd. All rights reserved.