微米锡刷镀层对AgCuZnSn钎料性能的影响

Effect of micro tin brush-electroplated coating on properties of AgCuZnSn brazing filler metals

关键词:  锡刷镀层  银钎料  熔化温度  润湿性  抗拉强度

Key words:  tin brush electroplated coating  silver-based brazing filler metal  melting temperature  wettability  tensile strength

摘要:

以BAg34CuZnSn钎料为研究对象,在其表面刷镀微米锡层,利用SEM和XRD表征锡刷镀层的组织和结晶取向,采用差热分析仪(DSC)、润湿试验炉、万能拉伸试验机分析刷镀锡含量对钎料熔化温度、润湿性、抗拉强度的影响,并对刷镀锡后钎料的电阻率和断后伸长率进行了讨论. 结果表明,BAg34CuZnSn钎料表面微米锡刷镀层平整、致密,孔隙率小,结晶晶粒呈现明显的(200),(112)择优取向. 随着钎料表面刷镀锡含量升高,AgCuZnSn钎料的DSC吸热峰向左偏移、熔化温度逐渐降低,钎料润湿面积和断后伸长率呈上升趋势,而钎料的抗拉强度和电阻率逐渐下降. 在刷镀锡含量为2.0%时,钎料的润湿面积和断后伸长率最大,而钎料熔化温度、抗拉强度和电阻率最低.

Abstract:

Tin coating were brush electroplated on BAg34CuZnSn brazing filler metals. The surface microstructure and crystallization orientation of tin coatings were observed by scanning electron microscopy and X-ray diffraction patterns. The effect of tin content on melting temperature, wettability and tensile strength of brazing filler metals were analyzed using the differential scanning calorimetry, wetting test furnace and tensile test machine, respectively. The electrical resistivity and elongation of the brazing filler metals were also discussed after brush electroplated tin. The results show that a smooth and uniform surface morphology of tin coating with small grain size and porosity is obtained, and its crystallization orientation is (200) and (112) crystal faces. The DSC endothermic peak shift to the left, the melting temperature of brazing filler metals decreases with the increasing of tin content. The wettability area and elongation of the brazing filler metals are improved, but the electrical resistivity and tensile strength of brazing filler metals are decreased. When the content of tin in the film is 2.0 %(wt.%), the wettability area and elongation of AgCuZnSn brazing filler metals are maximum, while its melting temperature, resistivity and tensile strength are minimum.