Research on the dynamic deformation behavior of the DP780 advanced high strength steel

The dynamic deformation behavior of the DP780 was studied by the quasistatic tensile experiment and the dynamic tensile experiment under the speed of the 0.1 m/s, 2 m/s, 10 m/s and 15 m/s. The strain-stress curves were obtained under the different strain rates and the mechanical behavior of DP780 constitutive equation was established based on the Johnson-Cook model. A new constitutive equation based on the variable-tensile speed v was developed to better forecast the strain rate and stress under the dynamic impact condition. The result turns out: the new constitutive is accordance with the experimental data.