Q355GNHD高耐候钢的动态高应变率塑性本构模型

Dynamic High Strain Rate Plastic Constitutive Model of Q355GNHD High Weathering Steel

Q355GNHD高耐候钢是先进轨道车辆车身的常用材料,其动态条件下的塑性本构模型对车身结构受力数值仿真至关重要。文章采用MTS 647 Hydraulic Wedge Grip和AutoCAE (HRST-I)高速试验机对Q355GNHD高耐候钢开展准静态、动态拉伸力学性能试验,获取了该型材料在0.001~500s-1应变率下的应力应变曲线;通过对该高耐候钢在应变率效应下受载变形规律的分析,确定了应变率加载效应;构建了应变率相关的Johnson-Cook硬化模型,确定了本构表征参数;最后运用ABAQUS平台,验证了模型的正确性。

Q355GNHD high weathering steel is a commonly used material for advanced rail vehicle body, the plastic constitutive model of which under dynamic conditions is of great significance for the numerical simulation of vehicle body stress. The experiments on quasi-static and dynamic tensile mechanical properties of Q355GNHD high weathering steelis were carried out by MTS 647 Hydraulic Wedge Grip and AutoCAE(HRST-I) high-speed testing machine. The stress-strain curves of the material at 0.001-500 s-1 strain rate were obtained through the experiments. The strain rate loading effect was determined by analyzing the deformation law of the high weathering steel under the strain rate effect. Then, the strain rate related Johnson-Cook hardening model was constructed and the constitutive parameters were determined. Finally, the correctness of the model was verified by ABAQUS platform.