Processing map for hot working of as extruded AZ31B magnesium alloy

The deformation behavior of AZ31B magnesium alloy as extruded under hot compression conditions was characterized in the temperature range of 200 - 400 degrees C and strain rate range of 0.001 - 1 s(-1). The processing maps were obtained at different strains. The results show that the map exhibits flow instabilities as two domains. The domain at beyond 300 degrees C and strain rate of 1 s(-1) appears with a peak efficiency of power dissipation about 56% occurring. This domain is expected to happen in a hot process, such as hot rolling, hot extrusion and hot forging. There is high efficiency of power dissipation at temperature beyond 350 degrees C and strain rate 0.001 s(-1). Such domains suggest the occurrence of superplastic deformation.