J-C model based failure criterion and verification of Q235 steel

Abstract

In this paper, we conducted quasi-static and dynamic tensile tests on Q235 steel at different temperatures using the Instron tensile strength tester and the split Hopkinson bar and studied the effects of temperature, strain rates and stress triaxiality on the steel's failure strains of Q235. The results show that Q235 steel's failure strains increase with a rise in temperature but decrease with a rise the strain rates while, with a rise in the stress triaxiality, they decrease at first but then increase. Based on these results and combining them with numerical simulation, we modified the item of temperature effects and proposed a revised three-section failure criterion of stress triaxiality for J-C failure model, with relevant parameters determined and verified using Taylor impacting experiments and corresponding numerical simulations. The experimental results accord well with those from simulation.