Adhesive strength and tensile fracture of Ni particle enhanced Sn–Ag composite solder joints

✍ Scribed by H.T. Lee; Y.H. Lee

• Publisher: Elsevier Science
• Year: 2006
• Tongue: English
• Weight: 1006 KB
• Volume: 419
• Category: Article
• ISSN: 0921-5093
• DOI: 10.1016/j.msea.2005.12.021

✦ Synopsis

This study forms composite solders by adding 0.5-3 wt% of Ni particles in situ to Sn-3.5 wt%Ag lead-free solder. Cu/solder/Cu specimens are prepared by dipping two Cu rods into a solder bath to produce a solder joint. Some of the joint specimens are retained in the as-soldered condition, while the others are aged at 150 • C for 100, 200, 400, or 500 h, respectively. The experimental results reveal that the addition of Ni to the molten Sn-Ag solder leads to the formation of in situ Ni 3 Sn 4 dispersoids. The adhesive strength of the joint is found to increase with increasing Ni content in the as-soldered specimens. In general, the strength of the thermally processed specimens reduces as the thermal storage time increases. The Sn-Ag-0.5 wt%Ni joints show a mixture of ductile and brittle fracture, whereas the joints containing more than 1 wt% of Ni show mainly brittle fracture with solder residue at the exposed (Cu,Ni) 6 Sn 5 IMC layer.