About this Abstract |
| Meeting |
2026 TMS Annual Meeting & Exhibition
|
| Symposium
|
Nix Award and Lecture Symposium: Recent Developments in Understanding Deformation Behavior and Mechanisms in Metals at High Temperature
|
| Presentation Title |
Local Phase Transformation Strengthening: How Stacking Faults and Defect Phases Enhance Creep Properties |
| Author(s) |
Steffen Neumeier, Andreas Bezold, Ashton J. Egan, Nicolas Karpstein, Jan Vollhuter, Erdmann Spiecker, Mathias Goken, Michael J. Mills |
| On-Site Speaker (Planned) |
Steffen Neumeier |
| Abstract Scope |
Recent studies on solute segregation at planar defects within L12-ordered precipitates during high-temperature deformation of superalloys have underscored its vital role in enhancing creep strength. This research specifically examines CoNi-based superalloys, delving into the thermodynamic and kinetic factors that govern solute segregation and the subsequent formation of defect phases. Utilizing high-resolution scanning transmission electron microscopy and energy-dispersive spectroscopy, we demonstrate that stacking faults can transition into ordered phases, significantly improving mechanical properties. Our findings highlight the necessity of rapid local ordering along these stacking faults to mitigate the adverse effects of microtwinning. Furthermore, specific alloying elements, particularly Ta, have been shown to influence deformation mechanisms and phase transformations. A subsequent study successfully generated a high density of stacking faults through pre-deformation, resulting in enhanced yield and creep strengths at elevated temperatures. This comprehensive analysis provides critical insights for the design of next-generation superalloys with superior creep resistance and mechanical performance. |
| Proceedings Inclusion? |
Planned: |