汽车B柱碰撞失效变形过程仿真重现

Simulation of automotive B-pillar collision failure deforming process

为了预测整车侧面碰撞试验中B柱的碰撞性能,应用Hypermesh/Ls-Dyna软件建立B柱零部件级碰撞仿真模型。根据整车碰撞试验中B柱的变形情况设置仿真模型中B柱约束条件,并依据整车和蜂窝铝质量以及蜂窝铝形状选择合适的冲击块的形状和质量,调整B柱和冲击块的相对高度位置以符合真实碰撞试验。由于B柱含有多种不同材料,故综合考虑多种强度焊点失效和多种材料断裂失效,根据不同金属材料间的极限焊点力的大小和材料的极限断裂应变来设置仿真中焊点和材料的失效。最终结果表明,仿真准确地复现了焊点失效和板料断裂失效现象。该仿真分析也为B柱及类似零部件的碰撞仿真提供了合理方法,提高了仿真的合理性。

To predict the collision performance of B-pillars in the vehicle side collision test,Hypermesh/Ls-Dyna software was used to establish B-pillar component-level collision simulation model.The B-pillar constraints were set in the simulation model according to the deformation of the B-pillar in the vehicle collision test,and the appropriate shape and mass of the impact block were selected according to the mass of the vehicle and honeycomb aluminum and the shape of the honeycomb aluminum,the relative height position of the B-pillar and the impact block was adjusted to match the true crash test.Since the B-pillar contains many different materials,multiple strength solder joint failures and multiple materials fracture failures were considered,the solder joint and material failure in the simulation were set according to the ultimate solder joint force between different metallic materials and the ultimate fracture strain of the material.The final result shows that the simulation accurately reproduce the solder joint failure and the sheet fracture failure phenomenon.The simulation analysis also provides a reasonable method for the collision simulation of B-pillar and similar parts,improves the rationality of the simulation.