| About this Abstract |
| Meeting |
2025 TMS Annual Meeting & Exhibition
|
| Symposium
|
Phase Stability, Phase Transformations, and Reactive Phase Formation in Electronic Materials XXIV
|
| Presentation Title |
Striped Strain-Induced Coherency Loss Leading to Metastable Nanoprecipitate Phase Transformation in Al-Zn-Mg Alloys |
| Author(s) |
Yu-ning Chiu, Tsai-fu Chung, Chung-yi Yu, Shih-kang Lin |
| On-Site Speaker (Planned) |
Yu-ning Chiu |
| Abstract Scope |
We utilized molecular dynamics (MD) simulations and atomic-level STEM characterization and strain mapping to elucidate the continuous phase transformation phenomenon during the η'→η_2 transition in Al-Zn-Mg alloys. A unique striped compressive strain is observed within the bulk of metastable η' nanoprecipitates. This striped compressive strain is identified as the primary cause of coherency loss in η', subsequently facilitating the transformation to the η_2 phase. Our findings suggest that the precipitate transition is predominantly initiated by the accumulation of strain at the coherent interface, with the driving force for this phase transformation being the release of strain energy. The continuous structural and compositional evolution of the transformation process has been comprehensively characterized through both MD simulations and STEM observations. This study provides the first mechanistic elucidation of the η'→η_2 transition, thereby offering strategic guidance to enhance the stability of these nanoprecipitates. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Aluminum, Computational Materials Science & Engineering, Phase Transformations |