| About this Abstract |
| Meeting |
2021 TMS Annual Meeting & Exhibition
|
| Symposium
|
Phase Transformations and Microstructural Evolution
|
| Presentation Title |
The Origin and Stability of Nanostructural Hierarchy in Nickel-base Superalloys |
| Author(s) |
Subhashish Meher, Larry Aagesen, Tresa M. Pollock |
| On-Site Speaker (Planned) |
Subhashish Meher |
| Abstract Scope |
A combined experimental and phase-field modeling approach has been used to explore a hierarchical structure at nanoscale for enhanced coarsening resistance of ordered γ′ precipitates in a multicomponent, high-refractory nickel-base superalloy. The hierarchical microstructure formed in this alloy is composed of a γ matrix with γ′ precipitates that contain embedded, spherical γ precipitates, which do not directionally coarsen during high-temperature annealing but do delay coarsening of the larger γ′ precipitates. Atom probe tomography suggests that the supersaturation of Co, Ru, and Re in the γ′ phase is the driving force for the phase separation, leading to the formation of this hierarchical microstructure. Representative phase-field modeling highlights the importance of larger γ′ precipitates to promote stability of the embedded γ phase and to delay coarsening of the encompassing γ′ precipitates. These results suggest that the hierarchical material design has the potential to influence the high-temperature stability of precipitate strengthened metallic materials. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Characterization, Phase Transformations, Copper / Nickel / Cobalt |