Cu/Sn37Pb/Cu钎焊接头界面微观结构及其剪切性能  

Interface Microstructure and Shear Properties of Cu/Sn37Pb/Cu Solder Joints

作　　者：万永强 胡小武[1] 徐涛[1] 李玉龙[1] 江雄心[1] WAN Yongqiang;HU Xiaowu;XU Tao;LI Yulong;JIANG Xiongxin(School of Mechanical Electrical Engineering,Nanchang University,Nanchang 330031)

机构地区：[1]南昌大学机电工程学院,南昌330031

出　　处：《材料导报》2018年第12期2003-2007,2014,共6页Materials Reports

基　　金：国家自然科学基金(51465039;51665038;51765040);江西省自然科学基金(20151BAB206041;20161BAB206122)

摘　　要：本工作借助扫描电镜(SEM)等手段,针对Cu/Sn37Pb/Cu钎焊接头进行剪切断裂实验,考察并分析钎焊及等温时效处理后焊点接头金属间化合物(IMC)的生长情况以及搭接焊点的剪切强度和断裂模式,旨在深入研究高体积分数界面IMC层对钎焊接头剪切性能及断裂形貌的影响。实验结果表明:在时效处理过程中,界面Cu3Sn层逐渐增厚且逐渐变得平坦。此外,在Cu3Sn/Cu界面观察到柯肯达尔空洞现象,随着时效时间的延长,空洞数量增多且尺寸变大。随着界面IMC层厚度增加,接头的剪切强度先增加后下降,这可能是由于脆性IMC厚度过大或粗化的富Pb相和富Sn相增多引起的。当时效时间与钎焊时间较短时,焊点具有较高体积分数的本体焊料,焊点断裂模式为韧性断裂,随着时效时间或钎焊时间的延长,焊点内IMC体积分数逐渐升高,焊点断裂模式开始转变为韧脆混合断裂,最后转变为脆性断裂。This work aims to deeply investigate the influences of a high volume fraction of interfacial intermetallic compound（IMC）upon the shear properties and fractured surface morphologies of the Cu/Sn37Pb/Cu solder joints.We conducted the shearfracture test,explored and analyzed the IMCs＇ growths,shear strengths and fracture modes of a series of Cu/Sn37Pb/Cu solder joints which differed in reflowing time and aging time.Our experiment observed the gradual thickening and flattening of the interfacial Cu3Sn layer as well as the increasing and enlarging Kirkendall voids at the Cu3Sn/Cu interface as the aging treatment processed.The thickening of the interfacial Cu3Sn layer led to an increase→ decrease trend of the joint＇s shear strength,which might be attributed to the excessive thickness of the brittle IMC layer or the grain coarsening of Sn-rish phase and Pb-rich phase.The solder joints with shorter aging time and reflowing time had a relatively higher volume fraction of bulk solder and displayed a ductile fracture mode.However,as the aging time or reflowing time were prolonged,the fracture mode gradually changed into a ductile-brittle mixed failure mode,and to a ductile fracture mode finally.

关 键 词：钎焊接头 时效处理 钎焊时间 柯肯达尔空洞 剪切强度 断裂模式 

分 类 号：TG425[金属学及工艺—焊接]