摘要为解决多孔陶瓷真空钎焊润湿时温度高、保温时间长、需真空环境和活性元素等缺点，利用超声波辅助方法实现多孔陶瓷的快速润湿，研究了超声功率对润湿效果的影响。结果表明，超声波作用下Sn9Zn 非活性钎料在230 ℃ 时仅需10 s 即可实现对多孔Si3N4陶瓷的润湿。超声功率为333.3 W 时，钎料可渗入陶瓷基体25 μm；渗入层的宽度随超声功率的增加而增大；超声功率为1000 W 时，渗入层的厚度可达80 μm。因焊接温度低，冷却后渗入层内的残余应力很小，陶瓷和钎料结合紧密、无裂纹。透射电镜的测试结果表明，润湿界面主要富集O 元素和Zn 元素。本文中多孔陶瓷的快速润湿可归因于钎料内的超强声空化作用，空化泡溃灭产生极高的温度、压力和液体流速，使非活性钎料在极短的时间内完成对陶瓷的润湿。
To solve the problems of high temperature, long holding time, vacuum environment and active elements when vacuum brazing porous ceramics, this work used ultrasonic assistance to realize the rapid wetting of porous ceramics, and the effect of ultrasonic power on the wetting effect was studied. The results showed that the Sn9Zn nonactive solder wetted the porous ceramics within 10 s at 230 ℃ under ultrasonication. When the ultrasonic power was 333.3 W, the solder infiltrated the ceramic matrix by a width of 25 μm. The width of the infiltration layer increased with increasing the ultrasonic power. The width of the infiltration layer was 80 μm when the ultrasonic power was 1000 W. Due to the low temperature during the wetting process, the residual stress in the infiltration layer after cooling was low, and thus the ceramic and the solder were closely bonded without cracks. The results of transmission electron microscopy showed that the wetting interface was enriched with oxygen and zinc elements. In this work, the rapid wetting of the porous ceramics can be attributed to the intense cavitation of the solder inside the microchannel of the porous ceramics. The extremely high temperature and pressure caused by the collapse of cavitation bubbles caused the non-active solder to rapidly wet the porous ceramics.
2022, 
