变压边力对拼焊板U形件成形性能影响的研究

Effect of Variable Blank Holder Force on Formability in U Channel Forming with Tailor Welded Blank

拼焊板由于两侧材料差异导致成形性能下降。利用变压边力控制技术能够提高板料成形性能。研究了随位置变化压边力和随行程变化压边力两种变压边力控制方式对拼焊板U形件成形性能的影响。结果表明,利用变压边力控制技术,能够提高拼焊板U形件成形性能。在随位置变化压边力控制方式中,当薄侧压边力小于厚侧压边力,可以缓解侧壁变形程度,但会加剧焊缝移动量;当薄侧压边力大于厚侧压边力,可以缓解薄侧底部变形程度,减小焊缝移动量。在随行程变化压边力控制方式中,线性渐增压边力可以更好的改善拼焊板底部材料变形不均匀性,减小焊缝移动。

The tailor welded blank has poorer formability due to material difference. The sheet metal formability can be improved by variable blank halder force control The effect of blank holder force （BHF）changing with travel distance or position on U channel forming with tailor welded blank is investigated. The results show that the formability of U channel forming with tailor welded blank is improved by variable BHF. With BHF changing with travel distance, the deformation degree of the side wall in thinner blank is decreased and the weld movement is increased when the BHF is smaller in thinner blank. The deformation degree of the bottom in thinner blank is decreased and the weld movement is decreased when the BHF is bigger in thinner blank. With BHF changing with position, the deformation degree of the bottom in thinner blank is decreased and the weld movement is decreased by the linearly increasing BHF.