针对SnBi/Cu接头在服役过程中组织和性能变差的问题，通过用扫描电镜(SEM)观察时效前后Sn35Bi-1Fe/Cu接头组织，结合EDS和XRD分析，分析接头组织变化；利用万能试验机，测试接头力学性能，研究Fe颗粒对时效过程中SnBi/Cu接头组织及性能影响. 结果表明，焊后Sn35Bi-xFe/Cu (x = 0%，0.3%，0.7%，1.0%和1.5%)接头的抗剪强度随Fe颗粒含量先增加后降低. 当Fe颗粒含量为1% (质量分数，%)时，取得最大值50.23 MPa，且Sn35Bi-1.5Fe/Cu接头的力学性能依旧比Sn35Bi/Cu接头好；在恒温时效阶段，Sn35Bi-1Fe/Cu接头中Fe颗粒通过对Bi相的钉扎作用，以及与Sn反应生成FeSn2化合物，消耗晶界能量，降低Bi相的迁移速率，抑制Bi相粗化，还能有效降低界面IMC层的生长速率，抑制界面Cu3Sn的生成，改善接头在服役阶段的力学性能.
To solve the problem of poor tissue stability of SnBi alloys during servicing, the microstructure of Sn35Bi-1Fe/Cu joints before and after aging was observed by scanning electron microscope (SEM), combined with energy spectrum analysis (EDS) and XRD, to analyzed the tissue changes of joint, and the mechanical properties of joints were analyzed by universal testing machine. The influence of Fe particles on SnBi/Cu joint structure and properties during aging was studied. The results show that with the increasing of contents of Fe particles, the shear strength of Sn35Bi-xFe/Cu (x = 0%, 0.3%, 0.7%, 1.0% and 1.5%) joints increases first and then decreases. When the Fe particle content is 1% (wt.%), the maximum value is 50.23 MPa, and the mechanical properties of Sn35Bi-1.5Fe/Cu joints are always better than those of Sn35Bi/Cu joints; during the constant temperature aging stage, Fe particles in the Sn35Bi-1Fe/Cu joint through pinning the Bi phase, and grain boundary energy was consumed by reacting with Sn to form FeSn2 compound to decreased Bi phase migration rate, lead to Bi phase coarsening was inhibited, at the same time, growth rate of interface IMC layer was decreased, the generation of interface Cu3Sn was suppressed, the mechanical properties of the joints in the aging stage was improved.
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