液态钎料薄层中超声空化泡的成长与破裂

通过进行液态钎料Sn-9Zn的铺展试验,观察超声作用下钎料空化泡的成长破裂情况,得出液态钎料在超声作用下发生填缝行为并且形态以扇形进行扩散。通过Matlab语言,在超声空化理论的基础上,从温度、超声频率、空化泡初始半径以及空化泡崩溃时的最大温度和最大压力四个方面,对Sn-9Zn,Sn-0. 7Cu和Zn-5Al三种液态钎料空化泡的成长和破裂进行模拟,得到了空化泡的运动情况。结果表明,温度越高,空化效应越弱;超声频率增大,空化效应减小;空化泡初始半径越小,空化泡的空化效应越明显;空化泡崩溃的最大温度同绝热指数成正比,而崩溃时的最大压力同绝热指数和反应体系的温度成反比。研究结果对超声波辅助钎焊中液态钎料空化效应的研究和应用提供了参考。

Growth and fracture of ultrasonic cavitation bubbles in thin layer of liquid solder

The spreading test of liquid Sn-9Zn brazing material was carried out to observe the growth and rupture of the brazing cavitation bubble under ultrasonic action. It is concluded that the liquid solder penforms behavior of filling soldering seam and diffuses in the shape of a fan. Through the Matlab language and on the basis of ultrasonic cavitation theory, the growth and fracture of Sn-9Zn, Sn-0.7Cu and Zn-5Al liquid solder cavitation bubbles were simulated from four aspects of temperature, ultrasonic frequency, initial radius of cavitation bubbles and maximum temperature and pressure when cavitation bubbles collapsed, and the motion of cavitation bubbles was obtained. The results show that the higher the temperature is, the weaker the cavitation effect is. The higher the ultrasonic frequency is, the weaker the cavitation effect is. The smaller initial radius of the cavitation bubble is, the more obvious of the cavitation effect of the cavitation bubble is. The maximum temperature at which cavitation bubbles collapse is directly proportional to the adiabatic index, while the highest pressure at which cavitation bubbles collapse is inversely proportional to the adiabatic index and the temperature of the reaction system. The research results provide a reference for the research and application of liquid solder cavitation effect in ultrasonic assisted brazing.