Using EBSD analysis for exploring the recrystallization behavior of hot-rolled Mg-Gd alloy

The microstructure, texture and mechanical properties of a Mg-0.6Gd (wt.%) alloy processed by hot-rolling at 450 °C to 85% of thickness reduction and subsequently annealed at temperatures ranging from 150 to 450 °C for 1 h were investigated using electron backscatter diffraction (EBSD) and Vickers microhardness measurements. The microhardness increased from 51.2 to 56.3 Hv with increasing annealing temperature at 250 °C due to the precipitation of the Mg5Gd phase and then decreased gradually to 38.5 Hv up to 450 °C owing to the static recrystallization and grain growth. Meanwhile, the recrystallized grain size was stable up to annealing at 250 °C (~ 1 μm) and then increased significantly to a value of 39 μm at 450 °C. Limited dynamic recrystallization, particle-stimulated nucleation and recrystallization at shear bands are the main mechanisms leading to the weakening and spreading of the deformation basal texture during the isochronal annealing treatment.