确定了辊弯成形中DP980高强度钢板的应变速率范围,在3种应变速率条件下进行了DP980高强度钢板的单向拉伸试验,并对试验数据进行非线性拟合,建立了与应变速率相关的Johnson-Cook本构模型;应用所建本构模型进行辊弯成形有限元模拟,并与相应的辊弯成形试验结果加以对比.结果表明,所建立的本构模型具有较高的精度,可用于辊弯成形工艺的进一步优化.
The strain rate ranges were determined and the uniaxial tensile tests of DP 980 steel sheet under three strain rates were performed. With the non-linear fitting of the experiment data, the strain rate dependent Johnson-Cook constitutive model was established. Meanwhile, an finite element model of roll forming process with the established constitutive model was constructed, and the corresponding experiment was conducted. The resrults indicate that the established constitutive model is reliable, and can be used in further study of roll forming process optimization.