Microstructure and texture evolution during high-temperature compression of Al-Mg-Si-Zr-Mn alloy

The hot deformation behavior of an Al-Mg-Si-Zr-Mn alloy was investigated by performing uniaxial compression tests over a temperature range of 400-550 degrees C and strain-rate range of 0.001-1 s-1. A decline ratio map was generated and divided into three different domains to understand the correlation between the flow stress behavior and various microstructural softening mechanisms. In domain I (deformed at 400-500 degrees C and 1 s-1), work hardening was more predominant than dynamic recovery (DRV). In domain II (deformed at 400-550 degrees C and 0.1-0.01 s-1), the microstructure was more homogenous than that in domain I. DRV was the main softening mechanism, with a dynamic equilibrium between DRV and work hardening. Owing to the higher deformation temperature and lower strain rate in domain III (450-550 degrees C and a strain rate of 0.001 s-1), the deformed structure almost completely disappeared, and a large number of dynamic recrystallized grains were formed. The microstructure was dominated by a combination of DRV and dynamic recrystallization softening mechanisms. Under these conditions, the flow stress decreased significantly with increasing strain owing to the presence of 44% dynamic recrystallized grains and slight coarsening of dispersoids. Textural analysis revealed the presence of strong Goss {011} (100), moderately Rotated Cube {001} (110), and Copper {112} (111) components in domains I and II. In contrast, Goss and S textures were moderately developed when deformation was performed in domain III.