Structures and mechanical properties of high-entropy carbides ceramics calculated based on first-principles

This review paper published in AI & Materials explores the implementation of first-principles calculation method within high-entropy carbides ceramics (HECCs) research, specifically examining its role in compositional regulation, evaluation metrics for single-phase formation capability, current limitations, and prospective developments for ultra-high temperature conditions. The work summarized the principle and calculation process of the representative first-principles calculations method, and reviewed the usability in the estimation of composition stability, structural design and mechanical property of HECCs. Finally, the prospect of the first-principles calculation method in the study of HECCs was prospected.

High-entropy carbides ceramics (HECCs) are single-phase solid solutions prepared from more than four single-metal carbides in equal molar ratio or close to equal molar ratio. Various possibilities for composition regulation and structural design make it excellent performance by maximizing the configuration entropy, such as good structural stability, excellent mechanical properties and functional properties. However, the traditional trial-and-error method is inefficient and difficult to meet the increasing application requirements. Fortunately, the advent of material simulation techniques has revolutionized R&D methodologies, providing robust tools for effectively improving material characteristics and streamlining system control mechanisms, which has dramatically shortened the development cycle for advanced HECCs materials.

This article summarized methods for accurate prediction and simulation of HECCs crystal structure based on first-principles calculations. For HECCs, it tended to form face-centered cubic structure. The formation ability of single-phase HECCs was tested by different evaluation parameters, such as mixed Gibbs free energy, entropy formation ability and lattice constant difference. While, the advantages and limitations of each criterion were introduced in detail.

The article also summarized the results of electronic structure information by first-principles calculation, such as band structure and DOS of HECCs. The results showed that HECCs exhibited characteristics of covalent bonds, ionic bonds, and metal bonds, while the bonding strength between metal and carbon atoms varied with the type of metal atom.

In addition, based on first-principles calculation, this article summarized the prediction of mechanical properties, and explained the influence of pressure, lattice distortion and grain boundary structure on the elastic modulus of HECCs.

In conclusion, the article confirmed that the first-principles calculation can effectively predict the crystal structure, single-phase formation ability, stability, and mechanical properties of HECCs, and shorten the development cycle and avoid resources waste.

This review “Structures and mechanical properties of high-entropy carbides ceramics calculated based on first-principles” was published in AI&Materials.
Guan J, Zhao X, Fang S, Liu Y, Zang X, et al. Structures and mechanical properties of high-entropy carbides ceramics calculated based on first-principles. AI Mater. 2025(1):0006, https://doi.org/10.55092/aimat20250006.