| About this Abstract |
| Meeting |
2025 TMS Annual Meeting & Exhibition
|
| Symposium
|
Electronic Packaging and Interconnection Materials II
|
| Presentation Title |
The Effect of Recent Heating on the Room Temperature Microstructure of Sn-Bi Alloys |
| Author(s) |
Xiaozhou Ye, Stuart David McDonald, Xin Fu Tan, Kazuhiro Nogita |
| On-Site Speaker (Planned) |
Xiaozhou Ye |
| Abstract Scope |
Sn-Bi alloys have the potential for significantly lower melting temperatures compared to Sn-Cu or Sn-Ag-Cu lead-free solder alloys. Due to the low melting points, these alloys experience higher homologous temperatures compared to conventional soldering alloys for equivalent conditions. Previous studies have found that given sufficient time, Bi precipitates can dissolve on heating and reprecipitate on cooling. This process directly affects the microstructure and mechanical properties over a finite time period. Thus, in-situ time-lapse optical microscopy was used with a polarising filter to image the structure of Sn-Bi samples of varying composition immediately after cooling from elevated temperatures to room temperature. Changes were seen in the grain structure and compared to SEM observations of precipitation occurring under identical conditions. The implications of these findings are discussed with respect to mechanical properties and reliability as well as considerations for accelerated thermal cycling tests of Sn-Bi solder alloys. |
| Proceedings Inclusion? |
Planned: |