| 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 |
On the formation of interstitial solute ordered complexes in bcc high-entropy alloys from first-principles |
| Author(s) |
Pedro Borges, Robert Ritchie, Mark Asta |
| On-Site Speaker (Planned) |
Pedro Borges |
| Abstract Scope |
Using first-principles calculations, we sample the solution energy of interstitial C, N and O atoms in bcc NbTaMoW and NbTaTiHf high-entropy alloys. We find a wide-range for the solution energies arising from chemical fluctuations in the vicinity of the interstitial atom, which we model using a cluster-expansion (CE) approach. We combine the CE model with a grand canonical Monte Carlo algorithm to study the formation of interstitial ordered complexes. Specifically, we examine different local chemical order (LCO) configurations in the alloy, and we show that large clusters of interstitials may form only if the details of the LCO emphasize the disparity between favorable and unfavorable sites in the lattice. Additionally, we use the CE model with a kinetic Monte Carlo framework to study diffusion of the interstitials. We find that LCO enhances correlated diffusion and alters the activation energy with respect to the random solid solution. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Computational Materials Science & Engineering, High-Entropy Alloys, Mechanical Properties |