差厚拼焊板零件焊缝线偏移的控制方法

Control Method of Weld Line for Tailor-welded Blank Parts with Different Thicknesses

基于差厚拼焊板成形时由于板料发生塑性变形从而不可避免地会出现焊缝线偏移现象,采取预先对坯料焊缝线进行调整优化的方式来缩小成形后焊缝线与设计焊缝线的偏差。先在压料面或填补的孔洞上延伸合并分离的焊缝线,然后将焊缝线离散成系列点后通过网格映射法建立设计焊缝线、坯料焊缝线及成形后焊缝线三者之间的位置映射关系,然后通过仿真计算获取成形后焊缝线与设计焊缝线各对应离散点之间的偏差,并依据偏差值对坯料焊缝线离散点进行相应的偏移,获得坯料理想的曲线焊缝。在此基础上对曲线焊缝直线化,并根据直线焊缝坯料的仿真计算结果对坯料焊缝进行适当的偏转和平移,从而缩小成形后焊缝线相对于设计焊缝线的偏差。冲压试验结果表明该方法是有效的,同时也揭示了成形后焊缝线相对于设计焊缝线有偏差主要是因为坯料选用了直线焊缝。

Deviations between the design weld lines and the formed weld lines were inevitable in the stamping processes of TWB with different thicknesses due to the plastic deformations, so a method to shrink the deviations by adjusting the weld lines on the blanks in advance was put forward. Firstly, design weld lines were transformed into a integrated curves by extending to the binder or the filled holes according to the process supplement surfaces, then the integrated ones were discretized into a series of points to establish the position relationship of each discrete point between the three of the designed weld lines, the blank lines and the formed lines, then the deviations of each corresponding points between the formed weld line and the design lines were calculated through stamping simulations, the ideal weld curve on blank could be acquired through adjusting the blank discrete point according to the deviations calculated before. Based on these, the weld curves of blanks would be transformed into a straight line, which would be rotated and moved properly according to stamping simulation results to further shrink the deviations between the formed weld line and the design lines. The stamping test results show that the method is effective and reveals the main sources of deviations are coming from straight weld lines of the blank.