Sn-2.5Ag-0.7Cu-0.1RE/Cu钎焊界面区IMC及接头性能

Interface Intermetallic Compound in Sn-2.5Ag-0.7Cu-0.1RE/Cu and Joint Performance

采用扫描电镜和X射线衍射等检测手段,研究了钎焊工艺参数对Sn-2.5Ag-0.7Cu-0.1RE/Cu界面金属间化合物(IMC)长大及钎焊接头剪切强度的影响。结果表明,Sn-2.5Ag-0.7Cu-0.1RE/Cu钎焊界面区形成了波浪状Cu6Sn5金属间化合物(IMC)。随钎焊时间延长、钎焊温度升高,界面波浪状Cu6Sn5相转变为较大尺寸的扇贝状,其厚度及界面粗糙度相应增大。当钎焊温度为270℃、钎焊时间为180s时,Cu6Sn5相厚度较薄,为2.2μm;界面光滑,其粗糙度为1.26μm,接头剪切强度值最高。

Effects of soldering processing parameters on the growth of interface intermetallic compound and shearing strength of Sn-2.5Ag-0.7Cu-0.1RE/Cu soldering joint were investigated by SEM (scanning electron microscope) and XRD(X-ray diffraction). The results indicate that wave-like Cu6Sn5 phase is created at the interface of the soldering joint after soldering. With extending soldering time and increasing soldering temperature, wave-like Cu6Sn5 phase is converted into scallop-like structure with bigger size, which results in the increase of thickness and interface roughness. Cu6Sn5 phase with 2.2 μm in thickness and 1.26 μm in roughness can be generated with soldering at 270 ℃ for 180 s, which is responsible for the highest shearing strength of soldering joint.