About this Abstract |
Meeting |
2024 TMS Annual Meeting & Exhibition
|
Symposium
|
Computational Thermodynamics and Kinetics
|
Presentation Title |
Point Defects and Diffusion in Refractory Carbides from First-principles Calculations |
Author(s) |
Indiras Khatri, Raj Koju, Yuri Mishin |
On-Site Speaker (Planned) |
Yuri Mishin |
Abstract Scope |
Refractory carbides, such as TaC and HfC, are candidates for ultra-high temperature applications. Knowledge of diffusion coefficients in such carbides is essential for optimizing the synthesis and processing routes and predicting creep deformation rates. We present a computational study of atomic transport in refractory carbides based on DFT calculations integrated with a statistical-mechanical model of point-defect disorder and a kinetic model of diffusion. The calculations predict equilibrium concentrations of point defects and their clusters as a function of temperature and chemical composition near stoichiometry. Diffusion coefficients are predicted for the single-vacancy, divacancy, and several other diffusion mechanisms. The computational methodology developed can be applied to diffusion calculations in other ordered compounds. |
Proceedings Inclusion? |
Planned: |
Keywords |
Modeling and Simulation, Ceramics, Computational Materials Science & Engineering |