| About this Abstract |
| Meeting |
2025 TMS Annual Meeting & Exhibition
|
| Symposium
|
Electronic Packaging and Interconnection Materials II
|
| Presentation Title |
Reliability of Solder Joints Under Extreme Conditions of Elevated and Cryo Temperatures for In-Space Applications |
| Author(s) |
Manish Kumar, Sid Pathak, Ralph Napolitano |
| On-Site Speaker (Planned) |
Manish Kumar |
| Abstract Scope |
We report results from the microstructural characterization and micromechanical response of terrestrial versus microgravity solders under extreme cryogenic and elevated temperatures, and various thermal cycling conditions mimicking space exploration (–157ºC to +121ºC outside the ISS). Under cryogenic conditions, we examine the effects of β-to-α phase transformation in Sn below 13ºC, associated volume and internal stress changes, and ductile to brittle transition in various Sn-based solders. Accelerated aging effects are probed at elevated temperatures (up to +120ºC).
Evidence of β-Sn to α-Sn phase transformation was found from our spherical indentation stress-strain analysis, showing significant softening in Sn(111) single crystal at -120°C (absent in 40Pb-60Sn solder). Evidence of DBT was observed from in-situ SEM micropillar experiments. These results demonstrate lower plastic strain at instability, higher yield strength, and higher instability stress at cryo temperatures compared to RT, underscoring the importance of small-scale testing on solder under extreme temperatures in space exploration. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Joining, Characterization, Phase Transformations |