汽车覆盖件拉延成形工艺参数多目标优化

Multi-objective optimization of drawing process parameters for automobile panels

针对汽车覆盖件拉延成形中容易产生起皱、破裂、拉延不充分的问题,以汽车引擎盖外板为例,提出了一种正交试验设计和二次多项式逐步回归相结合的多目标优化方法。首先,运用单因素变量法研究了工艺参数对拉延成形质量的影响,得出主要影响因素;其次,针对各因素进行正交试验设计,应用二次多项式逐步回归法对试验数据进行拟合,得到二次多项式代理模型,并对代理模型精度进行分析;然后,构造多目标优化模型,以加权函数最小为优化目标,得出在保证拉延成形充分的前提下,最大增厚率的最小值以及所对应的工艺参数组合;最后,应用优化后的工艺参数进行模拟仿真,获得了良好的拉延成形效果。研究结果表明,使用优化后的工艺参数进行试模,获得的引擎盖外板的最大减薄率为16.837%,最大增厚率为10.171%,成形质量较好;应用基于正交试验设计和二次多项式逐步回归的多目标优化方法够控制和预测成形质量、减少试模次数、降低生产成本,为此类零件的研究提供了参考,具有指导和借鉴意义。

Aiming at the problems of wrinkling,cracking and insufficient drawing in the drawing process of automobile panels,taking the automobile engine hood outer panel as an example,a multi-objective optimization method based on orthogonal test design and quadratic polynomial stepwise regression was proposed.Firstly,the influences of process parameters on drawing quality were studied by single factor variable method,and the main factors were obtained.Secondly,the orthogonal test design was carried out according to the main factors,the test data were fitted by quadratic polynomial stepwise regression method,the quadratic polynomial agent model was obtained,and the accuracy of the agent model was analyzed.Then,the multi-objective optimization model was constructed,taking the minimum weighting function as the optimization objective,the minimum value of the maximum thickening rate and the corresponding combination of process parameters were obtained on the premise of ensuring the full drawing forming.Finally,the optimized process parameters were used to simulate,and good drawing effect was obtained.The results indicate that using the optimized process parameters to trail,the maximum thinning rate of outer panel for engine hood is 16.837%,the maximum thickening rate is 10.171%,and the forming quality is good.The application of multi-objective optimization method based on orthogonal test design and quadratic polynomial stepwise regression can control and predict the forming quality,and reduce the number of trail and production costs,which provides a reference for the research of such parts and has guiding and reference significance.