(1. 华北水利水电大学 机械学院，郑州450045； 2. 哈尔滨工业大学 先进焊接与连接国家重点实验室，哈尔滨 150001)
摘 要: 以BAg50CuZn钎料为基体，采用硫酸盐镀液体系在其表面电镀锡，经热扩散处理制备了镀锡银钎料。借助扫描电镜、能谱分析仪、X射线衍射分析仪等手段分析银基钎料锡电镀层的表界面形貌、化学元素组成、界面物相，并对其表面和界面化学元素进行线扫描和面扫描分析。结果表明：锡电镀层结晶晶粒呈现明显的(101)、(112)结晶取向，晶体生长方式为“向上生长”+“侧向生长”混合模式；基体钎料与锡电镀层结合紧密，经热扩散处理二者之间发生了互扩散作用，形成扩散界面区。在扩散界面区，镀层中的Sn元素与钎料中的Cu、Ag元素形成了Cu3Sn相和Ag3Sn相。Sn元素在银基钎料锡电镀层中分布均匀、无偏析现象。电镀锡银钎料扩散界面区主要存在Ag相、Cu相、CuZn相、Ag3Sn相、Cu3Sn相，其中Ag相、Cu相、CuZn相来自基体钎料。银基钎料锡电镀层的结合界面是化合物型形式。
关键字: 银基钎料；锡电镀层；表面-界面；能谱分析
（1. School of Mechanical Engineering, North China University of Water Resources and Electric Power, Zhengzhou 450045, China; 2. State Key Laboratory of Advanced Welding and Joining, Harbin Institute of Technology, Harbin 150001, China）
Abstract:The sulfate electrolyte was applied to electroplating tin on the surface of BAg50CuZn brazing filler metals, and silver brazing filler metals with electroplating tin was prepared by the thermal diffusion treatment method. The surface-interface morphologies, chemical element compositions and interfacial phases were investigated by scanning electron microscopy (SEM), energy dispersive spectrometry (EDS) and X-ray diffractometry (XRD), respectively. And the chemical elements of the surface and interface were analyzed by line scan and plane scan. The results show that tin electroplated coating and substrate brazing alloys combine firmly, the crystallization orientation of tin electroplated coating is (101) and (112). Tin crystallization displays upward and lateral mixed growth modes. The diffusion interface zone forms because of the mutual diffusion between tin electroplated coating and substrate brazing alloys. The Sn element of tin coatings and Ag, Cu elements of substrate brazing alloys form Ag3Sn phase and Cu3Sn phase at the diffusion interface zone. The distribution of Sn element in tin electroplated coating and substrate brazing alloys is uniform and non-segregation phenomenon. The microstructure of diffusion interfacial zone is composed of Ag phase, Cu phase, CuZn phase, Ag3Sn phase and Cu3Sn phase, in which the Ag phase, Cu phase and CuZn phase are derived from the substrate brazing alloys. The bonding form of compound type appears at the interface of tin electroplated coating and silver brazing alloys.
Key words: silver brazing alloys; tin electroplated coating; surface-interface; energy spectrum analysis
