摘要
The hot deformation behavior of extruded AZ80 magnesium alloy was investigated using compression tests in the temperature range of 250–400 °C and strain rate range of 0.001–1.000 s–1. The 3D power dissipation map was developed to evaluate the hot deformation mechanisms and determine the optimal processing parameters. Two domains of dynamic recrystallization were identified from the 3D power dissipation map, with one occurring in the temperature and strain rate range of 250–320 °C and 0.001–0.010 s–1and the other one occurring in the temperature and strain rate range of 380–400 °C and 0.001–0.003 s–1. In order to delineate the regions of flow instability, Prasad’s instability criterion, Murty’s instability criterion and Gegel’s stability criteria were employed to develop the 3D instability maps. Through microstructural examination, it is found that Prasad’s and Murty’s instability criteria are more effective than Gegel’s stability criteria in predicting the flow instability regions for extruded AZ80 alloy. Further, the 3D processing maps were integrated into finite element simulation and the predictions of the simulation are in good agreement with the experimental results.
The hot deformation behavior of extruded AZ80 magnesium alloy was investigated using compression tests in the temperature range of 250–400 °C and strain rate range of 0.001^(–1).000 s^(–1). The 3D power dissipation map was developed to evaluate the hot deformation mechanisms and determine the optimal processing parameters. Two domains of dynamic recrystallization were identified from the 3D power dissipation map, with one occurring in the temperature and strain rate range of 250–320 °C and 0.001–0.010 s^(–1)and the other one occurring in the temperature and strain rate range of 380–400 °C and 0.001–0.003 s^(–1). In order to delineate the regions of flow instability, Prasad's instability criterion, Murty's instability criterion and Gegel's stability criteria were employed to develop the 3D instability maps. Through microstructural examination, it is found that Prasad's and Murty's instability criteria are more effective than Gegel's stability criteria in predicting the flow instability regions for extruded AZ80 alloy. Further, the 3D processing maps were integrated into finite element simulation and the predictions of the simulation are in good agreement with the experimental results.
基金
financially supported by the National Science and Technology Major Project of China (No. 2012ZX04012011)
the National Natural Science Foundation of China (No. 51375306)
the National Basic Research Program of China (No. 2011CB012903)
the Shanghai Science and Technology Innovation Action Plan (No. 14521100600)
