合金元素Ga对Sn-9Zn无铅钎料性能的影响

研究了合金元素Ga的添加量对Sn-9Zn无铅钎料熔化特性、润湿性能及其焊点力学性能的影响.结果表明,添加合金元素Ga以后,合金的熔点显著降低,熔化温度区间有所增大,润湿性能得到明显改善;合金元素Ga的添加量(质量分数)在0.5%时,钎料的晶粒组织最为细小均匀,钎料焊点的力学性能最佳;当合金元素Ga的添加量大于1%时,钎料的润湿性能趋于稳定,钎料组织中晶界处出现黑色富Ga相,钎料焊点的力学性能大幅度降低.因此,Sn-9Zn无铅钎料中合金元素Ga的最佳添加量为0.5%.

Effects of Ga on properties of Sn-9Zn lead-free solder

Effects of Ga on melting characteristics and wetting properties of Sn-9Zn lead-free solder as well as the mechanical properties of the soldered joints were investigated, respectively.The results indicate that the melting point of Sn-9Zn lead-free solder decreases obviously, the melting range increases and the wettability is gradually improved with the addition of Ga.When the content of Ga is around 0.5 wt.%, the grains of microstructure are the finest and the most homogeneous, the best mechanical property of soldered joint is obtained.When the content of Ga is above 1wt.%, the wettability tends to be stable, some Ga-rich phases appear on the grain boundaries and the mechanical property of the soldered joint decreases sharply.In general, the optimum additive amount of Ga in Sn-9Zn solder is about 0.5 wt.%.