In order to achieve hot processing products with expected microstructures, the construction of corresponding relationships between micro-evolution mechanisms and hot processing parameters is essential. In this study, such corresponding relationships of as-cast AlCu4SiMg alloy were constructed by double evaluating processing maps and Zener-Holloman (Z) parameter maps. Based on the stress-strain data obtained from a series of isothermal compression experiments, the processing maps of AlCu4SiMg alloy were constructed at the strain of 0.3, 0.5, 0.7 and 0.9 s-1. The processing maps revealed that the optimal hot deformation parameter windows corresponding to dynamic recrystallization (DRX) micro-evolution mechanism mainly appear at high temperature and moderate strain rate. On the other hand, the response maps of Z parameter at discrete strains were constructed, and the ideal processing windows were calibrated at the domains with relatively low lnZ-value. A phenomenon was found that the optimal deformation parameter windows identified by Z parameter are more conservative than those identified by processing map. By integrating processing maps and Z parameter maps, the optimal processing parameter windows corresponding to DRX micro-evolution mechanism for AlCu4SiMg alloy were finally obtained.
Keywords:
Processing map; Dynamic recrystallization; Z parameter; Aluminum alloy
