铟含量对Sn-Bi-In钎料性能及钎焊界面组织的影响

Effect of Indium Content on Properties of Sn-Bi-In Solder and Structure at Brazing Interface

制备了Sn-(20-x)Bi-xIn(x=0,1,2,3,4,5,质量分数/%)钎料,分析了其熔化性能和润湿性能,并在铜基体上进行了钎焊试验,研究了铟含量对钎焊界面显微组织的影响。结果表明:随着铟含量的增加,钎料的熔点降低,当铟质量分数为5%时钎料中几乎不形成共晶组织;钎料的润湿角随铟含量增加先减小后增大,润湿面积先增大后减小,当铟质量分数为4%时钎料的润湿性最好;随着铟含量增加,钎焊界面金属间化合物层的厚度增大,金属间化合物由Cu_(6)Sn_(5)转变为Cu_(6)Sn_(5)和Cu_(6)(InSn)_(5)。

Sn-(20-r)Bi-xIn(r=0,1,2,3,4,5,mass fraction/%)solder was prepared,and its melting and wetting properties were analyzed.Brazing experiments were conducted on copper substrate with Sn-(2-x)Bi-r In solder,and the effect of indium content on the microstructure at the brazing interface was studied.The results show that with the increase of indium content,the melting point of the solder decreased.When the mass fraction of indium was 5%,almost no eutectic structure was formed in the solder.The wetting angle of the solder first decreased and then increased,and the wetting area first increased and then decreased with increasing indium content.When the mass fraction of indium was 4%,the wettability of the solder was the best.The thickness of intermetallic compound layer at the brazing interface increased,and the composition of the intermetallic compound changed from Cu_(6)Sn_(5)to Cu_(6)Sn_(5) and Cu_(6)(InSn)_(5).