Sn0.45Ag0.68Cu无铅焊点热冲击性能的研究  

Thermal Shock Performance of Sn0.45Ag0.68Cu Lead-Free Solder Joints

作　　者：孟国奇 杨栋华[1] 王怀山[1] 罗虎[1] 王青萌 刘鲁亭 许洁[1] 甘贵生[1] 

机构地区：[1]重庆理工大学,重庆400054

出　　处：《电子工艺技术》2015年第2期69-72,共4页Electronics Process Technology

基　　金：重庆市教委/科技研究基金项目(项目编号:KJ130813);特种焊接材料与技术重庆市高校工程研究中心开放课题基金项目(项目编号:SWMT201502;SWMT201503;SWMT201505)

摘　　要：采用Sn0．45A g0．68Cu亚共晶无铅钎料通过热浸焊获得铜接头，在－45～125℃的温度循环区间内对焊接接头进行200、400、600、800、1000周期高低温热冲击循环实验，分析了焊点的剪切强度变化，组织演变及界面IM C的生长规律。结果表明：焊点组织中弥散分布的Cu6Sn5相内部晶粒逐渐粗化长大，最后转变为圆形或者椭圆形；焊点界面IM C层厚度明显增厚，且由最初的细小扇贝状转变为大的波浪状，最终趋于平缓；焊点的剪切强度随热冲击循环周期的增加而急剧下降，经400周期的热冲击循环之后，焊点的剪切强度已下降了约22．5％，在400周期的热冲击循环后开始变得平缓，最后趋于稳定。A novel low-silver hypoeutectic Sn0.45Ag0.68Cu lead-free solder and hot dip soldering were used to form the joint of copper. The microstructure evolution and the variation shear strength of the solder joint were researched, cold thermal shock experiments have been conducted on solder joint under 200, 400, 600, 800, 1 000 cycles and temperature - 45 ~ 125 ℃. The results show that, the Cu6Sn5 phase distributed in the solder matrix coarsened at first, then grew upand gradually transformed to be round or elliptical. The thickness of the interfacial IMC in solder joint increased significantly at first, and then the initial small scallop-shape interfacial IMC became to be flat as the thermal shock cycles increased. The shear strength of solder joint declined significantly before 400 cycles during the thermal shock test, dropped by about 22.5%, then became weak, and finally turn into be stable. Conclusion The shear strength of solder joint became stable after 400 cycles thermal shock test.

关 键 词：无铅焊点 热浸焊 热冲击 

分 类 号：TN604[电子电信—电路与系统]