功率超声对Cu/Sn体系溶解行为的影响

_{摘要: 本文采用浸没法研究了在523K、553K和573K的温度下有无超声作用Cu/Sn体系的溶解行为。实验发现超声波作用下Cu丝在熔融Sn中的溶解速率是无超声作用的6.79~24.106倍。结合有限元模拟的方法分别从超声波空化效应、微射流效应和声流效应等角度出发解释这一现象。研究结果表明,空化泡坍塌瞬间会在Cu/Sn界面的局部产生1500K左右的高温,不但提高了Cu在Sn液中的固溶度极限,而且使“微点”区域Cu发生熔化;微射流效应能减薄金属间化合物(IMC)层厚度和改变其形貌,增加了原子扩散的通道;声流效应会产生搅拌作用,将Cu/Sn固液界面前沿的溶质Cu原子不断推向Sn液内部,使溶质原子溶度一直低于饱和溶解度。综合以上各方面的因素使得超声波作用下固体Cu在Sn液中溶解量和溶解速率显著增大。}

Effect of Power Ultrasound on Dissolution Behavior of Cu/Sn System

In this paper, the immersion method was used to study the dissolution behavior of Cu/Sn system with or without ultrasound at 523K, 553K and 573K.SIt is found that the dissolution rate of Cu wire in molten Sn under ultrasonic action is 6.79~24.106 times without ultrasonic effect.SCombined with the method of finite element simulation, this phenomenon is explained from the perspectives of ultrasonic cavitation effect, micro jet effect and acoustic streaming.SThe results show that the cavitation bubble collapse will produce a high temperature of about 1500K at the Cu/Sn interface, which not only increases the solid solubility limit of Cu in the Sn liquid, but also melts the Cu in the "micro-point" region; The micro jet effect can reduce the thickness of the intermetallic compound (IMC) layer and change its morphology, and increase the channel of atomic diffusion; the acoustic streaming will produce a stirring effect, and the solute Cu atom at the front of the Cu/Sn solid-liquid interface is continuously pushed to the Sn liquid.SInternally, the solute atom solubility is always lower than the saturated solubility.SCombining the above factors, the dissolved amount and dissolution rate of solid Cu in the Sn solution are significantly increased under the action of ultrasonic waves.