| About this Abstract |
| Meeting |
2023 TMS Annual Meeting & Exhibition
|
| Symposium
|
Refractory Metals 2023
|
| Presentation Title |
Study of the Interactions of Niobium with Oxygen from First Principles with Bayesian Uncertainty Quantification |
| Author(s) |
Colleen Reynolds, Tresa Pollock, Anton Van der Ven |
| On-Site Speaker (Planned) |
Colleen Reynolds |
| Abstract Scope |
Refractory metal BCC multi-principal element alloys are generating interest for their high strength and high temperature performance. However, the constituent materials readily interact with oxygen, both in an interstitial solid solution and through the formation of surface oxides. Niobium is an important constituent element though its interactions with oxygen are inconsistently described in the literature, warranting more detailed investigation. We have predicted the Nb-O phase diagram, ranging from the dilute solid solutions to oxygen-rich phases. Applying a novel algorithm, we systematically explored the compositional and structural space of oxygen-rich Wadsley-Roth phases. We used a first principles statistical mechanics approach that relies on cluster expansions and Monte Carlo simulations to predict elevated temperature thermodynamic properties. Bayesian uncertainty quantification techniques were implemented to assess the numerical accuracy of high temperature phase boundary predictions. We have also calculated gamma surfaces to evaluate the impact of these interstitials on the mechanical properties of niobium. |
| Proceedings Inclusion? |
Undecided |
| Keywords |
Computational Materials Science & Engineering, High-Temperature Materials, Modeling and Simulation |