Deformation mechanism in a coarse-grained Mg-Al-Zn alloy at elevated temperatures

Deformation behavior of a coarse-grained AZ31 magnesium alloy was investigated at elevated temperatures using commercial rolled sheet. The as-received material had equiaxed grains with an average grain size of 130 mum. The tensile tests revealed that the material exhibited high ductility of 196% at 648 K and 3x10(-5) s(-1). Stress exponent, grain size exponent and activation energy were characterized to clarify the deformation mechanism. It was suggested from the data analysis that the high ductility was attributed to the deformation mechanism of glide-controlled dislocation creep. In addition, constitutive equation was developed for the present alloy. (C) 2001 Elsevier Science Ltd. All rights reserved.