焊头几何尺寸对铜/铝超声波焊接接头塑性变形的影响

Effect of Sonotrode Geometry on Plastic Deformation of Welded Joint During Ultrasonic Welding of Al/Cu

进行了1 mm厚铜/铝异种金属超声波焊接实验研究,分析了焊头几何尺寸对工件表面接触区域变形、焊接区塑性变形的影响。结果表明:工件在高频振动作用下,焊头会在工件表面接触区域留下压痕,并使焊接区发生塑性变形,形成局部机械自锁。焊头面积相同时,圆形焊头更容易造成工件表面材料流动,从而形成更深的压痕,而矩形焊头能够产生更强烈的焊接区塑性变形。焊头形状相同时,面积小的焊头能够形成更深的压痕,而面积大的焊头使焊接区塑性变形程度更强烈。

The ultrasonic welding of pure copper and 6061 AI alloy with lmm was studied. The effects of sonotrode geometry on the weld morphology, depth of the imprints and plastic deformation in the weld zone were investigated. The results show that sonotrode produces indented imprints on the surface of welded sheets. The plastic deformation occurs at the interface due to the high-frequency ultrasonic vibration, which can lead to mechanical interlocking between materials. For different shapes of sonotrodes with identical area, the round sonotrode is more likely to cause material flow at the surface of the workpiece ,which can result in deeper imprint, while rectangular sonotrode can lead to stronger plastic deformation at the welding interface. Moreover, as for the same welding head shape, small sonotrode area can generate deeper indentation, while the large sonotrode can cause more intensive plastic deformation at the weld zone.