Effect of Y 2O 3 particles on microstructure formation and shear properties of Sn-58Bi solder

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Original languageEnglish
Pages (from-to)1046-1054
Journal / PublicationJournal of Materials Science: Materials in Electronics
Issue number10
Publication statusPublished - Oct 2010


In the present study, varying weight percentages of Y 2O 3 particles (3-5 μm) from 0 to 3% were incorporated into eutectic Sn-Bi solder matrix to form composite solders. It is found that the reinforcement particles were well dispersed in the solder matrix. They depressed the growth of intermetallic compound (IMC) layers and reduced the size of IMC grains. Since the Y 2O 3 particles serve as additional nucleation sites for the formation of primary Bi-rich phase, the size of both Bi-rich phase and the IMCs were decreased gradually with the Y 2O 3 content increasing. Shear tests were also conducted on as-soldered joints. The growth of solid-state intermetallic compounds layer was examined by thermal aging of the solder/Cu couple for a temperature range from 60 to 120°C and time periods from 50 to 500 h. Compared with Sn-58Bi solder, finer eutectic microstructures were obtained with Y 2O 3 addition after long time aging. The apparent activation energies calculated for the growth of the intermetallic compound layers were 72 ± 5 kJ/mol of Sn-58Bi, 74 ± 4 kJ/mol of Sn-58Bi-0.5wt%Y 2O 3, 81 ± 5 kJ/mol of Sn-58Bi-1wt% Y 2O 3 and 81 ± 7 kJ/mol of Sn-58Bi-3wt.% Y 2O 3, respectively. © 2009 Springer Science+Business Media, LLC.