Optimizing and identifying the process parameters of AZ31 magnesium alloy in hot compression on the base of processing maps

This paper conducted the compression tests at elevated temperatures to analyze the influence of process parameters on hot formability of AZ31. And the true stress-strain curves at different temperatures and strain rates were obtained. Three criterions including sensitive index of the strain rate (m-value), power dissipation factor (η-value) and flow instability (ξ(ε̇)-value) were calculated according to them. Based on the criterions, hot processing maps of AZ31 were constructed. Then the deformation mechanism and instability mechanism were analyzed through investigating the microstructure of stable and instable regions. Finally, the optimum process parameters were obtained. As a result, some defects could be avoided in forming process to obtain consistent properties.