Establishment and Prediction Accuracy Comparison of Isothermal Compression Constitutive Model of ZL702A Aluminum Alloy

Isothermal compression tests were conducted on ZL702A aluminum alloy under different temperatures （200, 350, 460, 500 ℃） and strain rates （0.1, 0.01, 0.001 s⁻¹） by using the Gleeble-3800 thermal simulator. According to the true stress-true strain curves, considering the influence of strain on the model parameters, the modified Johnson-Cook （m-JC） constitutive model, the modified Zerilli-Armstrong （m-ZA） constitutive model, and the Arrhenius constitutive model were constructed, and were used to predict the high temperature rheological behavior. The prediction accuracy of the models was evaluated. The results show that the absolute relative error between the prediction of flow stresses by the Arrhenius model and the test values varied significantly under different strains, demonstrating a notable strain sensitivity, and the prediction accuracy within the 0.10−0.25 strain range was relatively low. The absolute relative errors of the prediction by the m-JC model and the m-ZA model under different strains varied slightly, and the prediction accuracy was less affected by strain. The average absolute relative error of the m-ZA model was significantly lower than that of m-JC and Arrhenius models, with the highest correlation coefficient （0.997）, indicating a more excellent prediction effect.