Thermal Deformation Behavior and Processing Maps of As-Homogenized Mg-5.8 Zn-0.5 Zr-1.0 Yb Alloy
Isothermal compression tests at temperatures of 250–400°C and strain rates of 0.001–1 s−1 were performed in a Gleeble-1500 thermal simulator to investigate the hot deformation behavior of as-homogenized Mg-5.8 Zn-0.5 Zr-1.0 Yb alloy. The Arrhenius-type constitutive equation and hot processing maps were established based on these experiments. Two dynamic recrystallized (DRX) domains were identified as (1) 280–350°C and 0.15–1 s−1; (2) 330–400°C and 0.001–0.09 s−1. The DRX mechanisms of the above-mentioned two domains and the instability patterns of the unstable regions were analyzed by optical microscopy and electron backscatter diffraction. The results provide a fundamental insight into the processing design, microstructural evolution, and property control of the newly developed Mg-Zn-Zr-Yb alloy.