| Abstract Scope |
Multicomponent transition metal carbides are promising for extreme-environment applications, yet the composition space is vast and identifying candidates that are both synthesizable and hard remains challenging. In this talk, we describe a first-principles framework that screens this space for target properties. Combining density functional theory with a fine-tuned MACE interatomic potential, trained on roughly 28,000 DFT calculations across groups 4 to 6 transition metals and carbon, we predict phase stability and elastic properties across over 1500 equiatomic compositions in rocksalt, hexagonal, and hcp prototypes. Coupling free energy models with elasticity-based hardness surrogates, we identify synthesizable, hard compositions whose predicted stability at high temperature agrees well with experiment. The framework also uncovers a new family of stacking-ordered phases, corroborated by DFT, that are more stable than disordered rocksalt, hexagonal, or hcp structures and are accessible only in multicomponent compositions, revealing design space beyond conventional carbides. |