Plastic flow modeling of Ti-5Al-2Sn-2Zr-4Mo-4Cr alloy at elevated temperatures and high strain rates

Abstract

The true stress-strain relationships of Ti-5Al-2Sn-2Zr-4Mo-4Cr(TC17) alloy with a wide range of strain rates were investigated by uniaxial quasi-static and dynamic compression tests, respectively. Quasistatic compression tests were carried out with Instron 8874 test machine, while dynamic compression tests were performed with the split Hopkinson pressure bar (SHPB) which was installed with heating device and synchroassembly system. The dynamic mechanical behaviors tests of TC17 were carried out from room temperature to 800 °C at intervals of 200 °C and at high strain rates (5 500–1 9200 s−1). The stress-strain curves considering temperature-strain rate coupling actions were obtained. The Johnson-Cook constitutive model was developed through data fitting of the stress-strain curves. The material constants in the developed constitutive model can be determined using isothermal and adiabatic stress-strain curves at different strain rates. The Johnson-Cook constitutive model provided satisfied prediction of the plastic flow stress for TC17 alloy.