汽车金属材料断裂失效模型研究

Fracture Failure Model Study of Metal Material

随着CAE技术的发展,金属材料的断裂失效预测在汽车行业受到越来越多的重视,尤其是在整车碰撞等大变形情况下,高强度钢等金属材料的断裂失效模拟及预测显得尤为重要。文章以热成型钢B1500HS为研究对象,对比了显式动力学软件LS-DYNA中GISSMO及DIEC 2种失效模型,并通过一系列材料力学实验,获得了以上两种失效模型的相关参数。最终通过设计热成型B柱子系统试验对上述两种失效模型进行对比验证。结果表明,在本文案例中,DIEC失效模型可以更准确预测热成型钢的断裂失效行为。该研究可为CAE分析中高强钢等金属材料模型的选取及设置提供参考。

With the development of CAE technology, it is becoming more and more important to exactly predict the fracture failure of the hotformed steel, especially in the case of large deforma- tion like the high speed crash situation. This paper studies the failure characteristic of the hot - formed steel （B1500HS） and obtains parameters of the failure model GISSM and DIEC in LS - DYNA code by series of material experiments . Moreover, the established failure model is validated by a three points bending test of a B post. The results show that the DIEC model can predict the fracture failure behavior of the hot - formed steel correctly. This study may provide a reference for choosing a failure model and setting up its parameters.