| About this Abstract |
| Meeting |
2025 TMS Annual Meeting & Exhibition
|
| Symposium
|
Phase Transformations and Microstructural Evolution
|
| Presentation Title |
Strengthening superalloys via an extreme density of locally transformed stacking fault phases |
| Author(s) |
Andreas Bezold, Nicolas Karpstein, Lukas Amon, Jan Vollhüter, Erdmann Spiecker, Michael Mills, Steffen Neumeier |
| On-Site Speaker (Planned) |
Andreas Bezold |
| Abstract Scope |
Recent works have increasingly highlighted the critical role of solute segregation towards planar defects in enhancing the creep strength of superalloys during high-temperature deformation. In this study, we demonstrate that an extreme density of superlattice stacking faults (about 25 defects per precipitate) can be introduced into superalloys prior to creep deformation via an optimized predeformation strategy at elevated temperatures. High-resolution scanning transmission electron microscopy coupled with energy dispersive X-ray spectroscopy reveals that these stacking faults have already locally transformed into the ordered hexagonal χ and η phases. The introduction of this high stacking fault density significantly enhances yield and creep strengths up to 750 °C compared to the undeformed reference state. Additionally, this study explores the deformation behavior and discusses the thermodynamic and kinetic aspects of solute segregation and subsequent local phase transformations at the stacking faults. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Characterization, High-Temperature Materials, Phase Transformations |