Transactions of Nonferrous Metals Society of China The Chinese Journal of Nonferrous Metals

您目前所在的位置:首页 - 期刊简介 - 详细页面


Transactions of Nonferrous Metals Society of China

Vol. 29    No. 8    August 2019

[PDF Download]        


Effects of Ag contents in Sn–xAg lead-free solders on microstructure, corrosion behavior and interfacial reaction with Cu substrate

Department of Industrial Engineering, Faculty of Engineering, King Mongkut’s Institute of Technology Ladkrabang, Bangkok 10520, Thailand

Abstract:The effects of Ag on the microstructure and corrosion behavior of pre-soldering Sn-xAg lead-free solders, and on the formation of intermetallic layer of the solders with Cu substrate were investigated. The Ag contents (x) were 0, 3.0, 3.5, 4.0, and 5.0 wt.%. The Ag content played a role in the morphology of Ag3Sn phase in the solders. The microstructure analysis showed that the β-Sn phase was surrounded by eutectic networks in the 3.0Ag and 3.5Ag solders and large plate-like Ag3Sn formed in the 4.0Ag and 5.0Ag solders. Nonetheless, the Ag content slightly impacted the corrosion behavior of the as-cast solders as characterized using potentiodynamic polarization test. After soldering, only a single layer of a Cu6Sn5 intermetallic compound formed at the Sn–xAg/Cu interface. By comparison, the Cu6Sn5 intermetallic layer of the Ag-doped solders was thinner than that of the 0Ag solder. The fine Ag3Sn particles in the eutectic networks precipitating in the 3.0Ag and 3.5Ag solders effectively hindered the growth of Cu6Sn5 grains compared to large plate-like Ag3Sn in the 4.0 and 5.0Ag solders.


Key words: Sn-Ag lead-free solders; microstructure; Ag3Sn intermetallic phase; corrosion behavior; Cu6Sn5 intermetallic layer; wettability

ISSN 1004-0609
CN 43-1238/TG

ISSN 1003-6326
CN 43-1239/TG

主管:中国科学技术协会 主办:中国有色金属学会 承办:中南大学
湘ICP备09001153号 版权所有:《中国有色金属学报》编辑部
地 址:湖南省长沙市岳麓山中南大学内 邮编:410083
电 话:0731-88876765,88877197,88830410   传真:0731-88877197   电子邮箱