Constitutive relationships of hot stamping boron steel B1500HS

Abstract

Constitutive relationship of boron steel is one of the most necessary mathematical models in the numerical simulation of hot stamping. It describes the relationship of the flow stress with strain, strain rate and temperature. In order to simulate hot stamping and get the approximately correct simulation results, the specimens are designed and tested to build the constitutive equations of boron steel B1500HS. Isothermal uniaxial tensile tests are performed at 600-900° with the strain rate of 0.01 s−1, 0.1 s−1, 1.0 s−1 and 10 s−1 by the Gleeble thermo- mechanical simulator, and the true stress-strain curves at the relative conditions are gained. The experimental results show that, the flow stress rises with the decrease of the deformation temperature and with the increase of the strain rate. The constitutive equations depending on the strain, strain rate and temperature are attained by the regression analysis of experimental data. The comparison results show that the computational data using the constitutive relationships are well consistent with the experimental data.