Ni/P/Ce元素对SnAgCu无铅钎料性能和组织的影响

Effects of Ni/P/Ce Elements on the Properties and Microstructure of SnAgCu Lead-Free Solders

研究添加微量单一Ni、P或稀土Ce元素对Sn3.0Ag0.5Cu(质量分数,%)无铅钎料熔化温度、润湿性能、时效前后钎焊接头的剪切强度和显微组织的影响。结果表明:单一Ni、P和稀土Ce元素的添加,对Sn3.0Ag0.5Cu钎料合金的熔化温度影响很小;P元素的加入能够增大合金的润湿力,缩小润湿时间。加入单一的Ni或稀土Ce元素对合金的润湿性能和接头时效前的剪切强度影响不大,但能够很好地抑制高温时效引起的接头剪切强度的下降。此外,P元素的添加明显地改善了合金的抗氧化性能,但稀土Ce元素的添加对其有所恶化。这些性能的改变与微量Ni、P或稀土Ce元素对其显微组织的影响有关。

Effects of trace Ni, P or Ce element additions on the microstructure and the properties of the Sn3.0Ag0.5Cu solder alloy were investigated. Results show that single adding of Ni, P or Ce has little influence on the melting temperature of the Sn3.0Ag0.5Cu solder alloy. P addition can improve the wettability of the solder, i.e. the wetting force of the solder is increased, and the wetting time is decreased. Single adding of Ni or Ce has no significant effect on the wettability of the soldered alloy and the shear strength of the as-reflowed soldered joint, but can remarkably suppress the decrease of the shear strength of the solder joints due to the high-temperature aging. Besides, P addition significantly increases the oxidation resistance of the soldered alloy, but rare earth Ce addition deteriorates it. The property change of the Sn3.0Ag0.5 solder are attributed to the change of the microstructure caused by trace Ni, P, or rare earth Ce additions.