Constitutive Modeling for Hot Deformation Behavior of Al-5083+SiC Composite

In the present research, isothermal hot deformation behavior of aluminum 5083 alloy+15 (wt.%) SiC composite was obtained through compression test on INSTRON 8801 universal tensile testing machine (UTM) under a wide temperature range of 473-773K and strain rate range of 0.01-10s(-1). The experimental true stress-strain data were employed to establish constitutive equations based on modified Johnson-Cook (JC) model and modified Zerilli-Armstrong (ZA) model to predict the hot flow behavior of the composite. The flow stress values obtained from these two models were plotted against the experimental flow curves to check the accuracy of these models. Suitability of the models was evaluated by comparing correlation coefficient (R), average absolute relative error and relative errors of prediction. The results show that the hot flow stresses of the present material depend on temperature and strain rate significantly. Both the models give good description of the hot deformation behavior of the composite. The prediction accuracy is found to be higher for modified ZA model compared to modified JC model, though the number of materials constants involved and time needed to evaluate them to establish the model are lower for modified JC model.