超声波作用下Cu/Sn固-液界面IMCs层的形成与演变

Formation and evolution of IMCs layer at Cu/Sn solid-liquid interface by ultrasonic assisted soldering

利用超声波辅助钎焊工艺方法对Cu/Sn/Cu结构进行钎焊实验,研究超声波辅助作用下Cu/Sn固-液界面金属间化合物(IMCs)的形成与演变过程。结果表明:无超声作用时界面处Cu-Sn金属间化合物形貌逐渐由平直状转变为凹凸的扇贝状,其中Cu_6Sn_5的形成主要受扩散控制,而Cu_3Sn层的形成则是由反应控制。施加超声波后,通过观察不同超声条件下Cu-Sn金属间化合物形貌的微观结构演变,提出破碎-溶解模型。通过改变超声时间来控制界面Cu-Sn金属间化合物的厚度,从而改善钎焊接头性能。

The Cu/Sn/Cu structure was brazed by ultrasonic assisted soldering. The formation and evolution of Cu-Sn intermetallic compounds (IMCs) by ultrasonic assisted soldering process were investigated. The results indicate that the morphologies of interfacial Cu-Sn intermetallic compounds (IMCs) are gradually transformed from planar shape to scallop-like shape without ultrasonic, in which the formation mechanism of Cu6Sn5 is mainly controlled by diffusion, and the formation mechanism of Cu3Sn layer is controlled by the reaction. After applying ultrasonic, a crush-dissolution model is proposed by observing the evolution of the microstructure of Cu-Sn intermetallic compounds with different ultrasonic conditions. The thickness of the interfacial Cu-Sn intermetallic compounds is controlled by changing the ultrasonic time, which will improve the performance of the brazed joint.