焊点尺寸对微焊点拉伸断裂强度的影响

摘要

采用基于动态力学分析仪(DMA)的精密拉伸试验与ANSYS有限元数值模拟方法研究了“铜引线/Sn-3.0Ag-0.5Cu钎料/铜引线”三明治结构微焊点(直径均为200 μm,高度为75～225 μm)的拉伸断裂行为.结果表明:微焊点直径不变而高度为225,175,125和75 μm时,其拉伸断裂强度分别为79.8,82.8,92.5与104.6 MPa,即焊点尺寸(高度)减小会导致拉伸断裂强度增大,同时微焊点最终断裂位置由焊点中部向钎料/铜引线的界面处转移.%Adopting precise tensile testing based on the dynamic mechanical analyzer (DMA) and finite element numerical simulation method based on ANSYS software, the tensile fracture behaviors of "Cu wire/ Sn-3.Oag-O.5Cu solder/Cu wire" sandwich structure solder joints (with the diameter of 200 μm and thickness of 75-225 urn) were investigated. The results show that the average tensile fracture strengths of microscale solder joints are 79.8, 82.8, 92.5 and 104.6 Mpa when the joint's diameter is constant (200 μm) and the thicknesses are 225, 175, 125 and 75 μm in sequence. Also, the fracture position changes from the mid of the solder joint to the interface of Cu wire/solder when joint's thickness decreases.