Zhang Y.-P.,Institute of Soldering and Brazing Materials |
Wan Z.-H.,Institute of Soldering and Brazing Materials |
Xu L.,Institute of Soldering and Brazing Materials |
Liu F.-M.,Institute of Soldering and Brazing Materials |
Yang K.-Z.,Institute of Soldering and Brazing Materials
Cailiao Gongcheng/Journal of Materials Engineering | Year: 2010
Low-silver (Ag<1%, mass fraction) SAC lead-free solder alloys meet wettability and reliability problems. Effect of silver content, nickel and bismuth element additions on some key properties such as microstructures, wettability and copper dissolution property of solder alloys was investigated to seek the possible solution. The results showed that the regular change of microstructures, melting behavior and tensile property of the solder alloys was resulted by the increase of silver content; the additions of bismuth and nickel could improve the solderability (wettability) property of the alloys and lower the copper dissolution rate. It was also found that the copper dissolution rate of SAC0805BiNi solder is lower than SAC0307 and SAC305 solder alloys, and wettability is close to SAC305 alloy. The alloys with silver content between 0.3% and 1% mass percentages exhibit good ductility. Consequently, the overall performance of low cost solder alloys will be approaching to the SAC305 alloys with proper silver content and addition of alloy elements.