SMT中焊点形状对焊点可靠性的影响  

Effects of solder joint shape on joint reliability in SMT

作　　者：林健[1] 雷永平[1] 吴中伟[1] 张宁[1] 

机构地区：[1]北京工业大学材料学院,北京100022

出　　处：《电子元件与材料》2008年第2期60-64,共5页Electronic Components And Materials

基　　金：北京市属市管高等学校人才强教计划资助项目

摘　　要：根据SMT SnPb焊料焊点在热疲劳过程中的受载特点，采用有限元方法，建立了用于预测该种类型焊点热疲劳寿命的数值模型，并借热疲劳试验验证了模型的有效性。结果表明：热疲劳试验中，焊盘（焊盘1）伸出较短的SMT焊点在1440～1680周期之间发生大量破坏，且其热疲劳寿命要低于焊盘（焊盘2）伸出较长的焊点，这与有限元模拟预测的寿命结果基本一致。进而采用该模型研究了焊点形状对其热疲劳寿命的影响规律，在一定条件下，其结果可应用于无铅焊料。A numerical model was built up to predict the thermal fatigue lifetime of properties of SnPb joints in SMT by FEM. The thermal fatigue tests were carried out to test the numerical model. The results show that the during thermal fatigue test most of solder joint failure of pad 1 occurs from 1 440 to 1 680 cycles and the thermal fatigue lifetime of pad 1 is less than that of pad 2, it can be concluded that the predicted lifetime by FEM has a good agreement with the experimental result. Moreover, the numerical model is used to study the effects of solder joint shape on the：＇thermal fatigue lifetime of the joints in SMT. The results can be used in lead-free solders in fixed conditions.

关 键 词：电子技术 表面组装技术 焊点形状 热疲劳寿命 有限元方法 

分 类 号：TG40[金属学及工艺—焊接]