Zn含量对Sn-3.5Ag无铅钎料润湿性及微观组织的影响

Effect of Zn alloying on the wettability and microstructure of Sn-3.5Ag Pb-free solder

研究了不同Zn含量对Sn-3.5Ag无铅钎料润湿性及显微组织的影响.钎料润湿平衡测试表明,随着元素Zn在Sn-3.5Ag无铅钎料内含量的增加,对润湿时间影响不大,但润湿力下降.RMA松香基助焊剂的润湿性要优于无VOC水基免清洗助焊剂.钎料的微观组织分析表明,Zn与Ag之间形成ζ-AgZn金属间化合物,同时合金元素Ag与Sn之间形成Ag3Sn金属间化合物,这两种金属间化合物相与β-Sn基体共同组成的共晶相含量随着合金元素Zn含量的提高而增加.

Effect of Zn with different contents on the wettability and microstructure of Sn-3. SAg Pb-free solder is studied. The wetting balance test shows that with increasing of content of Zn in Sn-3. SAg Pb-free solder alloy, no obvious difference on wetting time is found, but wetting force decreases. The wetting force using RMA flux is better than that with a VOC-free water soluble flux. The optical microstructure analysis shows ^-AgZn and Ag3 Sn intermetallics are produced between Zn-Ag and Ag-Sn couples. With increasing of Zn content in solder alloys, the content of eutectic phases in microstructure composed of these two intermetallics and [3-Sn base increases.