Constitutive descriptions and microstructure evolution of extruded A5083 aluminum alloy during hot compression

The deformation behavior and microstructure evolution of extruded A5083 aluminum alloy were studied by performing hot compression tests at deformation temperatures ranging from 350 °C to 500 °C and strain rates ranging from 0.01 s−1 to 50 s−1. Inverse analysis was used to reduce the effects of inhomogeneous distributions of deformation and temperature on the flow curves. On the basis of the obtained flow curves, a set of constitutive equations was modeled to describe the deformation behaviors, and these equations can be regarded as the “material genome” as they provide a fundamental understanding of material behaviors during deformation. A model was developed to predict the flow stress under the entire range of experimental conditions. Error analysis verified the reliability of the model and confirmed it to be effective in predicting the flow stress. Microstructure observations confirmed dynamic recrystallization occurred. Besides, particle-stimulated nucleation was also observed, verifying that large particles can promote dynamic recrystallization. The effects of temperature and strain rate on microstructure evolution were analyzed. The relations between deformation behavior, microstructure and mechanical property were also discussed, the good correlation shows a possibility of controlling microstructure and mechanical property by selecting suitable forming parameters.