差厚拼焊板焊缝线偏移的控制研究

Research on Control of Weld Line Deviation of Tailor-welded Blank with Different Thicknesses

差厚激光拼焊板成形时由于板料发生塑性变形而不可避免地会出现焊缝线偏移。本文采取预先对坯料焊缝线进行优化的方式来缩小成形后焊缝线与设计焊缝线的偏差,先依据工艺设计模型延伸补全设计焊缝线,然后将设计焊缝线离散成系列点,并通过网格映射法反求获取其在坯料上的初始位置,确定参数优化区间和目标函数,应用均匀拉丁方方法构建响应面近似模型,最后通过遗传优化计算获得坯料上最佳的焊缝线分布。该方法可以有效减小成形后实际焊缝线与设计焊缝线的偏差。冲压试验结果表明本文提出的方法是有效的。

During the forming of laser tailor welded blanks with different thicknesses, the deviation of the weld line is inevitable due to the plastic deformation of the sheet. The method of pre-optimizing the weld line was adopted to reduce the deviation between the weld line and the design line after forming. First, the design weld line was extended and repaired according to the process design model. And then it was dispersed into a series of points. The initial position of the blank was obtained by the grid mapping method, the parameter optimization interval and the objective function were ascertained, and response surface approximation model was established by using uniform Latin square method. Finally, the distribution of the optimal weld line was obtained by genetic optimization calculation. The method can effectively reduce the deviation of the actual weld line and the design line. Stamping test results show that the method proposed in this paper is effective.