Two methods for modeling the flow stress behavior of magnesium alloy AZ61 under hot deformation

Abstract

In order to study the hot deformation behavior of magnesium alloy AZ61 and establish rational process parameters,the flow stress of this material was investigated under temperature of 523K~673K and strain rate of 0.001s-1~1s-1 by Gleeble 1500 thermo-mechanical simulator.According to the test data,deformation activation energy was evaluated and the formulation of peak stress was established which is dependent on temperature and strain rate.Then two different methods were proposed to model the flow stress and their accuracy was verified.The results show that the relative deviation is 5.46% if the influence of strain is directly considered,while it is 5.42% if the influence of strain is indirectly considered by incorporating dynamic recrystallization volume fraction.Both models agree well with experimental results.