Characterization of mechanical property of magnesium AZ31 alloy sheets for warm temperature forming

A method based on the numerical inverse approach to characterize the mechanical property of the Magnesium AZ31 alloy sheet for warm temperature forming was discussed in this work. In particular, temperature-dependent hardening and strain rate sensitivity were characterized based on uniaxial tensile test data measured at between 100 degrees C and 300 degrees C with the interval of 50 degrees C. Hardening deterioration associated with micro-void development as well as dynamic recovery and dynamic re-crystallization, observed beyond the uniform deformation limit, was also accounted for. Importance of the proper characterization of the hardening deterioration was confirmed by validating the failure by strain localization in the circular cup drawing test under the warm forming condition. With mechanical behavior properly described, failure with strain localization was predictable without referring to forming limit diagram but directly evaluating strain localization for material elements in this work. Uniaxial compression tests were also performed at various temperatures below 200 degrees C to assess asymmetric behavior in tension and compression. (c) 2015 Elsevier Ltd. All rights reserved.