Hot deformation and processing map of as-homogenized Mg–9Gd–3Y–2Zn–0.5Zr alloy

The hot deformation behavior of a newly developed as-homogenized Mg–9d–3Y–2Zn–0.5Zr (GWZ932) magnesium alloy has been investigated with Gleeble-3500 thermal simulator. Compression tests were performed in the temperature range of 410–470 °C and in the strain rate ranging from 0.01 s−1 to 10 s−1. The stress–strain behavior has been studied and it was found that the form of the flow stress curves was sensitive to temperature and strain rate. The processing map at the strain of 0.5 which represented steady-state flow was developed by plotting the variation of the efficiency of the power dissipation as a function of temperature and strain rate. Both safety deformation domain and instability regions were identified in the processing map. The microstructures evolution and dynamic recrystallized (DRX) were also analyzed and discussed. The results showed that the optimum hot working condition for the alloy, which has been determined based on the processing map and microstructures evolution, was deformation at the temperature of 450 °C with the strain rate of 0.01 s−1.