Flow behavior and processing map of as-cast Mg–10Gd–4.8Y–2Zn–0.6Zr alloy

Compression tests of Mg–10Gd–4.8Y–2Zn–0.6Zr alloy have been performed in the compression temperature range from 350 °C to 500 °C and the strain rate range from 0.001 s−1 to 1 s−1. The flow behavior has been investigated by the stress–strain behavior and dynamic recrystallization (DRX) behavior. The critical condition and the kinetics of DRX of the alloy deformed at the temperature of 500 °C and the strain rate of 0.01 s−1 were determined. The processing maps at different strains were established, which illustrated that the processing maps of the alloy was sensitive to strains. The optimum parameters for hot working of the alloy has been determined according to the processing map and microstructure at the true strain of 0.7, and that was the deformation temperature of 500 °C and the strain rate of 0.01 s−1.

The processing maps of the alloy deformed at the different strain ((a) 0.1, (b) 0.3, (c) 0.5 and (d) 0.7) obtained by means of overlapping a power dissipation map and an instability map, in which the shaded domain represents the instable region. The processing maps gained at different strains show obviously difference, that is to say, the deformation mechanism and microstructure transition of the alloy deformed with different strains are different and the processing maps of the alloy are sensitive to strains. It is necessary to choose correct processing map to optimize the deformation technics and conduct production of the alloy.Figure optionsDownload as PowerPoint slideResearch highlights▶ The processing map and the modeling of DRX of the alloy have been established. ▶ The processing maps at different strains have been investigated respectively. ▶ 3-D plots were used to describe the efficiency maps and the instability maps.