Quasi-Static Loading Responses and Constitutive Modeling of Al–Si–Mg alloy

Abstract

The flow behavior of the Al–Si–Mg alloy under uniaxial compression loading was investigated at different strain rates (10−3 s−1, 10−2 s−1,10−1 s−1, 100 s−1) at a wide range of temperatures (573 K, 623 K, 673 K, 723 K, 773 K). The results showed that the peak stress increase with the strain rate and decrease with the increase of temperature. According to the measured flow stress curves, a modified Johnson-Cook (J-C) constitutive model taking strain rate effect on thermo softening into account was proposed to delineate the flow behavior. The comparisons between the measured flow curves and the predicted ones showed them to be very close and the average error is 1.65%. The added experiments were also conducted for validating the modified model, and the predicted data well agreed with the measured flow stress curves. That indicated the modified Johnson-Cook model is reliable and can accurately delineate the flow behavior of Al–Si–Mg alloy.