| About this Abstract |
| Meeting |
2024 TMS Annual Meeting & Exhibition
|
| Symposium
|
Refractory Metals 2024
|
| Presentation Title |
Phase Stability in the Tantalum-nitrogen System From First Principles |
| Author(s) |
Jeremiah Thomas, Anton Van der Ven |
| On-Site Speaker (Planned) |
Jeremiah Thomas |
| Abstract Scope |
Tantalum nitrides are used as diffusion barriers in electronics and are also of interest due to their extremely high melting points. However, despite a range of computational and experimental studies, the tantalum-nitrogen system lacks an up-to-date and accurate phase diagram. In addition to recently discovered stable structures, there are many metastable and contested structures. For example, the 1:1 rocksalt phase of TaN is reported as a metastable structure in experimental literature but is dynamically unstable when simulated. Proposed stabilization mechanisms include cation and anion vacancies, antisite defects, and deformation to lower-symmetry structures. The ambiguity in phase stability makes this system a good candidate for density functional theory (DFT) calculations. We have applied DFT and Monte Carlo simulations to a large set of defected structures generated by our cluster expansion code, CASM, in order to create the phase diagram of the tantalum-nitrogen system. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Computational Materials Science & Engineering, Phase Transformations, High-Temperature Materials |