About this Abstract |
| Meeting |
2026 TMS Annual Meeting & Exhibition
|
| Symposium
|
Electronic Packaging and Interconnection Materials III
|
| Presentation Title |
Minor Ag and Zn Additions Altering the Microstructure, Properties, and Solderability of Sn–40Bi Alloy |
| Author(s) |
Yu-An Shen |
| On-Site Speaker (Planned) |
Yu-An Shen |
| Abstract Scope |
Sn–Bi-based alloys are widely used for low-temperature soldering due to their low melting points and good solderability. However, the high Bi content often leads to brittleness, prompting interest in partially reducing Bi content to improve ductility. This study examines the impact of minor Ag and Zn additions on the microstructure and properties of the Sn–40Bi (SB40) solder alloy. Alloys Sn–40Bi–2Ag (SBA402) and Sn–40Bi–2Zn (SBZ402) were prepared by casting. SBA402 exhibited a refined microstructure with dispersed Ag₃Sn and showed enhanced tensile strength, while SBZ402 featured a Zn-rich needle-like phase and reduced ductility. Interfacial analysis showed that SBA402/Cu formed a thin, uniform Cu₆Sn₅(Ag) layer, while SBZ402/Cu exhibited voids and thick Cu–Zn intermetallics. Thermodynamic calculations further supported the observations of the properties. These findings support the potential use of SBA402 in low-temperature soldering applications. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Joining, Electronic Materials, Mechanical Properties |