Constitutive Modeling of Hot Deformation Behaviors and Processing Maps of Mg-4.83Gd-2.36Nd-0.21Zr Alloy

Accurately assessing the hot workability and flow behavior is crucial in the preparation of high-performance wrought Mg-rare earth (RE) alloys. The hot deformation behaviors and workability of Mg-4.83Gd-2.36Nd-0.21Zr alloy are examined via Gleeble 3500 thermosimulation tests across a range of deformation temperatures from 350 degrees C to 450 degrees C and strain rates ranging from 0.001 to 1 s-1. The experimental results reveal that the flow stress of the experimental alloy decreases as the temperature increases and the strain rate decreases. The activation energies for deformation (Q) of the experiment alloy are calculated by the hyperbolic constitutive equation and range from 186.78 to 234.97 kJ mol-1. Strain compensation is incorporated in constitutive modeling, resulting in the correlation coefficient (R) of 0.9865 and the average absolute relative error (AARE) of 5.4639%. Further, the processing maps are constructed at different strains based on dynamic material models, from which the feasible processing window of the experimental alloy is determined in the areas of deformation temperatures of 425-450 degrees C and strain rates of 0.01-0.1 s-1. The hot deformation characteristics of casting Mg-4.83Gd-2.36Nd-0.21Zr alloy are investigated. The constitutive equation and processing maps of the alloy are established based on the flow stress curves. The microstructure evolution and the deformation mechanism of the alloy are analyzed. The feasible processing window of the alloy is within 425-450 degrees C/0.01-0.1 s-1.image (c) 2023 WILEY-VCH GmbH

Automated summary

Accurately assessing the hot workability and flow behavior of Mg-rare earth alloys is crucial. This study examined the hot deformation behaviors and workability of Mg-4.83Gd-2.36Nd-0.21Zr alloy through thermosimulation tests. The results revealed the flow stress, activation energies for deformation, and established processing maps for the alloy. The feasible processing window was determined to be within specific temperature and strain rate ranges.