基于RSM与GA的汽车后备箱盖板成形工艺参数多目标优化

Multi-objective optimization on process parameters for automobile trunk cover based on RSM and GA

针对某车型的后备箱盖板拉延成形时出现的破裂和起皱现象,首先,基于DYNAFORM建立后备箱盖板的有限元模型;其次,探究压边力x1、拉延筋1的阻力x2和拉延筋2的阻力x3对后备箱盖板拉延成形的综合影响,建立中心复合试验设计(CCD)方案,通过中心复合试验设计方案构建了影响成形的工艺参数的二阶响应面法(RSM)模型,以板料的最大减薄率y1和最大成形力y2为优化目标,建立多目标优化函数;运用改良型的遗传算法(GA)进行模型寻优,获得影响后备箱盖板成形的最佳工艺参数组合,即x1=520.05 kN,x2=80.03 N·mm,x3=82.18 N·mm;最后,对最佳工艺参数组合进行试验验证,试验结果表明,提出的方法可有效地提高汽车后备箱盖板的成形质量,同时对类似覆盖件的成形质量控制具有一定的指导意义。

For the problems of crack and wrinkle during the deep drawing of trunk cover for a certain car model,first,the finite element model of trunk cover was established based on DYNAFORM,and then the comprehensive influences of blank holder force x1,draw-bead resistance x2 and x3 on the deep drawing of trunk cover were explored. Then,a central composite design(CCD) scheme was established,and the second-order response surface method(RSM) model of the process parameters affecting the forming was constructed by the CCD scheme.Furthermore,a multi-objective optimization function was established by taking the maximum thinning rate y1 and the maximum forming force y2 of sheet metal as the sptimization objects,and the model optimization was conducted by improved genetic algorithm(GA) to obtain the best combination of process parameters affecting the forming of trunk cover with x1= 520 kN,x2= 80. 03 N·mm and x3= 82. 18 N·mm.Finally,the best combination of process parameters was tested and verified. The test results show that the proposed method effectively improves the forming quality of car trunk cover,which has certain guiding significance for the forming quality control of similar covering parts.