Dynamic recrystallization behavior and hot workability of Mg–2.0Zn–0.3Zr–0.9Y alloy by using hot compression test

•The dynamic recrystallization behavior and hot workability of the Mg–2.0Zn–0.3Zr–0.9Y Mg alloy are studied.•The safe and instable deformation domains for the hot working process with different grain size are obtained.•The effect of strain rate and deformation temperature on mechanism of DRX is discussed.•The optimum hot-working parameters with completed DRX grain size are determined.

The hot deformation behavior, dynamic recrystallization (DRX) evolution and hot workability of Mg–2.0Zn–0.3Zr–0.9Y alloy were studied by compression test. Compression experiments were performed in temperature range of 250–400 °C and strain rate range of 0.001–1 s−1 using Gleeble 1500D thermo-mechanical simulator. Based on the regression analysis for Arrhenius type equation of flow behavior, the apparent average activation energy of deformation was determined as Q = 236.2 KJ/mol. The DRX kinetic model of Mg–2.0Zn–0.3Zr–0.9Y alloy was established as XDRX=1-exp-1.30(ε-εcε∗)1.51. The DRX kinetic model is sensitive to the DRX mechanism changes caused by deformation conditions. The DRX kinetic model and instability zones were validated by means of microstructure observation.