A modified Johnson-Cook model of dynamic tensile behaviors for 7075-T6 aluminum alloy

作者：Zhang, Ding-Ni^*; Shangguan, Qian-Qian; Xie, Can-Jun; Liu, Fu

来源：Journal of Alloys and Compounds, 2015, 619: 186-194.

DOI：10.1016/j.jallcom.2014.09.002

• Strain rate
• Constitutive relation
• Johnson-Cook model
• 7075-T6 aluminum alloy
• Experiment

The dynamic mechanical behaviors of 7075-T6 aluminum alloy at various strain rates were measured by dynamic tensile tests using the electronic universal testing machine, high velocity testing system and split Hopkinson tensile bar (SHTB). Stress-strain curves at different rates were obtained. The results show that the strain rate hardening effect of 7075-T6 aluminum alloy is significant. By modifying the strain rate hardening term in the Johnson-Cook constitutive model, a new Johnson-Cook (JC) constitutive model of 7075-T6 aluminum alloy was obtained. The improved Johnson-Cook model matched the experiment results very well. With the Johnson-Cook constitutive model, numerical simulations of tensile tests at different rates for 7075-T6 aluminum alloy were conducted. According to tensile loading and stress-strain relation of 7075-T6 aluminum alloy, calculation results were compared with experimental results. Accuracy of the modified Johnson-Cook constitutive equation was further proved.

• 出版日期2015-1-15
• 单位上海师范大学