| About this Abstract |
| Meeting |
2025 TMS Annual Meeting & Exhibition
|
| Symposium
|
Local Chemical Ordering and Its Impact on Mechanical Behaviors, Radiation Damage, and Corrosion
|
| Presentation Title |
Thermodynamical and kinetical aspects of stacking fault segregation |
| Author(s) |
Andreas Bezold, Nicolas Karpstein, Jan Vollhüter, Erdmann Spiecker, Michael Mills, Steffen Neumeier |
| On-Site Speaker (Planned) |
Andreas Bezold |
| Abstract Scope |
The occurrence of solute segregation towards planar defects during high-temperature deformation in superalloys and its importance for creep strength became increasingly evident in recent years. In this work, we investigate thermodynamical and kinetical aspects of solute segregation in a CoNi-base superalloys. High-resolution scanning transmission electron microscopy coupled with energy dispersive spectroscopy measurements reveal that the equilibrium composition along these atomic-scale defects depends on the composition of the host phase, the corresponding bulk phase of the defect phase and the thickness of the defect phase. Our investigations indicate that defect phases with over eight layers already exhibit a bulk-like composition. Furthermore, the temporal evolution of these segregation processes is presented by investigating the segregation profile of stacking faults over 4 orders of magnitude (30 seconds to 200 hours) at 850 °C. Using the obtained results, we propose strategies to include these aspects for alloy design to create alloys with enhanced creep strengths. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Characterization, High-Temperature Materials, Phase Transformations |