基于响应面模型和遗传算法的汽车发罩外板冲压工艺参数多目标优化

以汽车发罩外板为例,将压边力、冲压速度、凹模与板料间摩擦系数和凸模与板料间摩擦系数作为工艺参数变量,以拉延工序最大减薄率和修边工序后最大回弹量为优化目标,应用中心复合试验设计(CCD)及有限元模拟获取样本数据。由试验数据建立二阶响应面模型,结合非支配排序遗传算法(NSGA-Ⅱ)实现多目标优化,得到优化的工艺参数组合为:压边力为1145kN,冲压速度为3480mm·s~(-1),凹模与板料摩擦系数为0.106,凸模与板料摩擦系数为0.13。基于优化的工艺参数指导模面回弹补偿分析并试模,研究结果表明,发罩外板实际冲压成形质量较好。

Multi-objective optimization on stamping process for automobile hood panel based on response surface model and genetic algorithm

For automobile hood panel, taking the blank holder force, the punch velocity, the coefficient of friction between die and blank, as well as the coefficient of friction between punch and blank as processing parameter variables,and the maximum thinning rate in the drawing process and the maximum springback in the trimming process as the optimization objectives, the sample data were obtained by the central composite design (CCD) method and the finite element simulation.Then, the quadratic response model was established by the test data, and the multi-objective optimization of processing parameters was achieved combining with the non-dominated sorting genetic algorithm (NSGA-II).Therefore, an optimized combination of process parameters was obtained with the blank holder force of 1145 kN, the punch velocity 3480 mm·s-1, the coefficient of friction between die and blank of 0.106, and the coefficient of friction between punch and blank of 0.13.Based on the optimized processing parameters, the springback compensation was guided, and the die tryout was conducted.The result shows that the stamping of automobile hood panel stamping is of good forming quality.