动态拉伸载荷下SMT焊点可靠性研究  

Research on Reliability of SMT Solder Joint in Dynamic Tensile Load

作　　者：王勇[1] 雷永平[1] 林健[1] 张志政[1] 赵海燕[2] 

机构地区：[1]北京工业大学,北京100124 [2]清华大学,北京100084

出　　处：《电子工艺技术》2009年第2期63-65,69,共4页Electronics Process Technology

基　　金：2007年度高等学校博士学科点专项科研基金项目(项目编号:20060005006);"十一五"国家科技支撑重点项目(项目编号:2006BAE03B02-2);北京市属市管高等学校"学术创性团队计划"项目"环境协调连接材料及加工技术"资助

摘　　要：对Sn37Pb和Sn3．0Ag0．5Cu（SAC305）钎料贴装的SMT组件进行了动态拉伸载荷下的机械疲劳试验研究，结果表明，Sn37Pb焊点的疲劳寿命要高于SnAgCu305。在峰值应力为40MPa时寿命差距达到最大，前者是后者2倍～3倍。同时，还分别得出了两种焊点在50％和10％破坏率下的S—N寿命曲线。通过对两种焊点试样横截面的显微观察，发现两种焊点均主要沿着三处位置开裂，然后随着疲劳周次‘的增加直至裂纹贯穿整个焊点。Two groups of SMT assemblies are investigated in mechanical fatigue test of dynamic tensile load, the results show that the fatigue lifetime of Sn37Pb solder joints is better than SnAgCu305. When the stress value is 40 MPa, life distance arrives to the maximum, and the former is the latterg 2 - 3 times. Meanwhile, the S - N life lines of two kinds of solder joints are obtained under 50% and 10% failure rate. Trough the optical microscope of cross - section of two kinds of solder joints, three crack positions can be found both in the two kind of solder joint, and the crack goes through the whole solder joint with the increase of fatigue cycles.

关 键 词：SMT 焊点 疲劳 破坏率 

分 类 号：TN606[电子电信—电路与系统]