基于热辊弯工艺的汽车前保险杠变强度优化设计

Optimization design on variable strength of automobile front bumper based on hot roll bending process

为提高某车型前保险杠横梁碰撞性能,优化其碰撞过程中的变形模式,基于热辊弯工艺特点,以前保险杠横梁不同承载区域的强度为变量,采用拉丁超立方生成样本数据并计算,对计算结果应用移动最小二乘法构建近似模型,以峰值载荷最大值为目标,以变形量为约束条件,通过遗传算法进行优化求解,得到汽车前保险杠横梁变强度优化设计方案。优化结果表明:变强度前保险杠方案相较于基础模型方案,峰值载荷提高了4%,变形量降低了65%,变形模式及碰撞性能方面均得到了提升。根据优化设计方案完成变强度热辊弯样件的试制,结果显示:通过在管件不同位置进行差异性淬火强化能够实现变强度分布。

In order to improve the collision performance and optimize the deformation mode during the collision process for on automobile front bumper beam,based on the characteristics of hot roll bending process,taking the strengths of different load-bearing areas in front bumper beam as variables,the sample data were generated and calculated by Latin hypercube method,and for the calculation results,an approximate model was built by mobile least squares method.Then,taking the maximum peak load as the target and the deformation amount as the constraint condition,the optimized solution was conducted by the genetic algorithm,and the optimized design scheme of variable strength for the automobile front bumper beam was obtained.The optimization results show that the peak load for the scheme of variable strength front bumper is 4% higher than the base model,and the deformation amount for the scheme of variable strength front bumper is 65% less than the base model.Therefore,both deformation mode and collision performance are improved.According to the optimized design scheme,the hot roll bending samples with variable strength were produced,and the result shows that the variable strength distribution is achieved by differential quenching strengthening at different positions of tube parts.