烧结温度对电磁压制Ag-25.5Cu-27Sn钎料显微组织及性能的影响

摘要

以纯金属粉末为原料,利用电磁压制技术制备了Ag-25.5Cu-27Sn钎料,并在100~500℃保温30 min进行烧结,研究了烧结温度对钎料相对密度、物相组成、显微组织、熔化特性,以及对其钎焊铜接头微观形貌和抗拉强度的影响.结果表明:随烧结温度的升高,钎料的相对密度先降低后升高,400℃烧结钎料的相对密度高于未烧结钎料的,并生成了稳定的ε1-Cu3 Sn和ε2-Ag3 Sn相;烧结使钎料的熔化温度略有提高,400℃烧结钎料的熔化温度比250℃烧结的降低了约4℃;400℃烧结钎料钎焊铜接头焊缝中的气孔数明显较少、组织均匀细小,其抗拉强度比未烧结钎料钎焊铜接头的提高了16%.%Ag-25.5Cu-27Sn brazing filler metal was prepared by magnetic pulse compaction using pure metal powders as raw materials,and sintered at 100-500 ℃ for 30 min.The effects of sintering temperature on relative density, phase composition, microstructure, melting property of the brazing filler metal, and on the micromorphology and tensile strength of the brazed Cu joint were studied.The results show that the relative density of the brazing filler metal first decreased then increased with the increase of sintering temperature.The relative density of the brazing filler metal sintered at 400 ℃ was higher than that of the unsintered brazing filler metal,and the stable phases ofε1-Cu3 Sn andε2-Ag3 Sn were formed.The melting temperature of the brazing filler metal was improved by sintering,and that of the brazing filler metal sintered at 400 ℃ was about 4 ℃ lower than that sintered at 250 ℃.With 400 ℃ sintered brazing filler metal,the number of pores in weld of the brazed Cu joint was relatively small and the microstructure was relatively homogeneity and fine.The tensile strength was 16% higher than that of Cu joint brazed with the unsintered filler metal.