Hot deformation behavior and constitutive modeling of homogenized 6026 aluminum alloy

The isothermal hot compression tests of homogenized 6026 aluminum alloy under wide range of deformation temperatures (673-823 K) and strain rates (0.001-10 s(-1)) were conducted using Gleeble-1500 thermo-simulation machine. According to the experimental obtained true stress-strain data, the constitutive equations were derived based on the original Johnson-Cook (JC) model, modified JC model, Arrhenius model and strain compensated Arrhenius model, respectively. Moreover, the prediction accuracy of these established models was evaluated by calculating the correlation coefficient (R) and average absolute relative error (AARE). The results show that the flow behavior of homogenized 6026 aluminum alloy is significantly affected by the strain rate and temperature. The original JC model is inadequate to provide good description on the flow stress at evaluated temperatures. The modified JC model and Arrhenius model greatly improve the predictability, since both of these models consider the coupled effects of deformation temperature and strain rate. However, to give more precise description, the influence of strain on the material constants should be introduced into Arrhenius model. (c) 2015 Elsevier Ltd. All rights reserved.