汽车用高强钢板动态拉伸试验及数据验证方法

DYNAMIC TENSILE TEST AND DATA VERIFICATION METHOD OF AUTOMOTIVE HIGH STRENGTH STEEL PLATE

钢板材料的力学性能具有明显的应变速率敏感性,精确测定材料的动态性能对于车身防撞性的准确预测具有重要的作用。基于万能试验机和卧式液压驱动试验机系统进行了高强度钢板的力学性能试验,得到了不同应变速率的真实应力-真实应变曲线。同时,设计了盒形件的压溃试验来验证材料动态试验数据的准确性。结果表明:利用拉伸试验获得的不同应变速率的真实应力-真实应变数据应用于有限元模拟分析,模拟盒形件冲击变形后样件形貌与压溃试验样品的变形形貌基本一致;有限元预测力-位移曲线和压溃试验得到的曲线大致重合,验证了动态试验的真实应力-真实应变曲线的准确性,实现了低成本测得高强度钢板动态拉伸参数和冲击变形形貌,提供了一种汽车防冲击及安全设计依据。

The mechanical properties of steel plate are an obvious sensitivity of strain rate.Accurate measurement of the dynamic properties of materials plays an important role in accurately predicting the collision resistance of the car body.Based on the universal testing machine and the horizontal hydraulic driving testing system,the true stress-true strain curves were obtained at the different strain rates.At the same time,the crush test of box-shaped parts was designed to verify the accuracy of dynamic testing data.The results indicated that the measured parameters by using the true stress-true strain data of different strain rates obtained by tensile test were applied to the finite element simulation analysis in order to study the deformation morphology of high strength steel under the crushing states in the application of automotive industry.The force-displacement curve was predicted by the finite element,which is roughly the same as the curve obtained from the crushing test.Therefore,it was verified that the accuracy of the real stress-strain curve at the different strain rates.And it assists to realize the low-cost measurement of dynamic tensile parameters of high strength steel plates.In addition,it can provide the possible design basis for the car impact protection.