基于压边力的无凸缘U形件拼焊板回弹及控制研究

Investigation of Springback of Tailor-welded Blanks and Control in Unflanged U-channel Forming with Blank Holder Force

采用固定压边间隙法获得恒定压边力值,对具有纵向焊缝的拼焊板在不同压边力作用下的回弹特性进行研究,并与光板对比;将正交试验设计和有限元软件相结合的方法应用到无凸缘U形件成形过程中,对成形过程中的变压边力形式进行了优化设计。结果表明,拼焊板及其光板的回弹随着压边力增加先增加后减小,压边力小时,拼焊板回弹介于对应的两光板之间,随着压边力增加,拼焊板回弹量在对应的光板之上。采用经优化设计的变压边力,拼焊板及其光板回弹与恒定压边力时相比明显减小,回弹控制效果好。

After obtaining the value of invariable blank homer force（BHF） through the means of fixing blankholder gap, springback characteristic of tailor- welded blanks （TWBs） with longitudinal welding line is investigated on different BHF, and it is compared with that of non - welded blanks. Proposed here is an optimization design for variable BHF. It combines orthogonal design of an experiment with FEM software. The results mainly show that with the increase of BHF, TWBs＇ springback increases first, and then tends to decrease , which is the same tendency as normal blanks. When BHF is small, TWBs＇ springback is in the midst of that of non - welded blanks; with the increase of BHF, TWBs＇ springback is the biggest among them. When the variable BHF gained by optimization design is actted on blanks, springback of both TWBs and non - welded blanks decrease more clearly than invariable BHF, and control of springback obtains good results.