About this Abstract |
| Meeting |
2027 TMS Annual Meeting & Exhibition
|
| Symposium
|
Hume-Rothery Symposium: Data-Driven Materials Discovery and Phase Stability
|
| Presentation Title |
Elucidating the role of solute-solute interactions on diffusion in Ni-based substitutional solid solutions |
| Author(s) |
Jinyoung Kwon, Najla Zulfikar, Kyoungdoc Kim |
| On-Site Speaker (Planned) |
Kyoungdoc Kim |
| Abstract Scope |
Solute diffusion plays a pivotal role in governing phase transformations and microstructural evolution. However, measuring substitutional solute diffusivity in Ni alloys remains challenging because of inherently slow diffusion rates, the high cost of experiments, and the complexity of multicomponent systems. Here, we perform first-principles calculations combined with the fourteen-frequency model to investigate the temperature-dependent dilute solute diffusion coefficients of solute pairs in fcc Ni. We find that secondary solutes generally enhance solute diffusivity, although the underlying mechanisms vary depending on solute type. The activation energy is primarily governed by impurity volume through strain relaxation, whereas the diffusion prefactor is mainly influenced by chemical bonding. In particular, electron localization alters the balance between bond stiffening and softening, thereby affecting vibrational migration entropy. The resulting dataset provides valuable kinetic parameters for modeling creep deformation and γ′ coarsening in Ni-based superalloys. Ultimately, these findings will support the design of high-strength Ni-based superalloys. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Computational Materials Science & Engineering, ICME, Copper / Nickel / Cobalt |