High Strain Rate Deformation Behavior of Mg–Al–Zn Alloys at Elevated Temperatures

High temperature deformation behavior of AZ31 and AZ91 magnesium alloys was examined by compression tests over a wide strain rate range from 10–3 to 103 s–1 with emphasis on the behavior at high strain rates. The dominant deformation mechanism in the low strain rate range below 10–1 s–1 was suggested to be climb-controlled dislocation creep. On the other hand, experimental results indicated that the deformation at a high strain rate of ~103 s–1 proceeds by conventional plastic flow of dislocation glide and twinning even at elevated temperatures. The solid-solution strengthening was operative for high temperature deformation at ~103 s–1.