Constitutive Modeling of High-Temperature Flow Behavior of Al-0.62Mg-0.73Si Aluminum Alloy

The high-temperature flow behavior of an aerospace structural material Al-0.62 Mg-0.73Si aluminum alloy was researched in this work. The isothermal compression tests were carried out in the temperature range of 683-783 K and strain rate range of 0.001-1 s(-1). Based on the obtained true stress-true strain curves, the constitutive relationship of the alloy was revealed by establishing the Arrhenius-type constitutive model and a modified Johnson-Cook model. It was found that the flow characteristics were closely related to deformation temperature and strain rate. The activation energy of the studied material was calculated to be approximately 174 kJ mol(-1). A comparative study has been conducted on the accuracy and reliability of the proposed models using statistics analysis method. It was proved by error analysis that the Arrhenius-type model had a better performance than the modified Johnson-Cook model.