Abstract A previous study has found that applying ultrasonic vibration in laser joining of Polyethylene terephthalate (PET) plastic to Ti metal can greatly reduce bubbles formed in the joint. In this study, the theoretical basis on the combined effects of pressure and temperature fields on the trajectory of bubbles was analyzed using finite element simulation. A non-uniform temperature field influences the evaporation momentum pressure acting on a bubble, causing it to travel from a low to a high temperature region. A properly designed ultrasonic transducer tool, however, can create an unbalanced pressure field around a bubble. Under the combined effects of these elements, bubbles in the molten pool can be made to escape from the joint. The predicted results and obtained experimental outcomes matched well, which were also supported by the evidence of captured high-speed camera images.

中文翻译：

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温度场和超声波振动对塑料与金属激光连接中气泡运动的综合影响

摘要 先前的研究发现，在聚对苯二甲酸乙二醇酯 (PET) 塑料与 Ti 金属的激光连接中应用超声波振动可以大大减少接头中形成的气泡。本研究利用有限元模拟分析了压力场和温度场对气泡运动轨迹的综合影响的理论基础。不均匀的温度场会影响作用在气泡上的蒸发动量压力，使其从低温区域移动到高温区域。然而，设计合理的超声波换能器工具可能会在气泡周围产生不平衡的压力场。在这些元素的共同作用下，可以使熔池中的气泡从接头处逸出。预测结果与得到的实验结果吻合良好，