考虑侧碰的汽车B柱加强板材料性能梯度优化

Optimization of yield stress distribution in B pillar reinforcement panel regarding side crashworthiness

为减轻汽车B柱的重量、提高B柱的侧面抗撞性及简化B柱的加工工艺,提出利用高强度钢板热成形技术生成变屈服强度的单一厚度B柱加强板对原车进行改进的措施。为了使热成形B柱的材料梯度分布趋于合理,利用有限元数值模拟对其进行了优化设计。以某轿车为例,基于响应面数值优化方法,采用部件碰撞仿真分析,对热成形B柱加强板的材料性能梯度分布进行了优化。对最终的优化结果进行了整车侧碰仿真,并与原车进行了对比。结果表明,优化后的热成形变梯度B柱使车身减重0.773 kg的同时较好地满足侧面碰撞的要求。

In order to reduce the mass of car body B pillar,improve its side crashworthiness and simplify the manufacturing process,a method using the hot formed B pillar was proposed.The method produces the B pilllar reinforcement panel with uniform thickness and varying yield strength by different cooling rate at hot forming.To make the distribution of the yield strength in the hot formed B pillar reasonable,an optimization design was performed by the finite element analysis.Taking a certain car as an example,an optimal distribution of the yield strength in the B pillar reinforcement panel material was obtained using the numerical optimization method of response surface and component collision simulation analysis.The optimized result was simulated with the vehicle side collision and compared with the original vehicle.The obtained results indicate that the car body using the optimized hot formed B pillar reinforcement panel with varying yield strength can reduce mass by 0.773 kg and improve the vehicle side crashworthiness.