First-Principles Modeling of High-Entropy Borides under Extreme Pressure and Temperature Conditions

High-entropy materials are of substantial interest due to their exceptional properties, such as high hardness, thermal stability, and oxidation resistance under extreme pressure and temperature conditions. However, predicting their properties remains challenging because of the vast combinatorial possibilities in both structure and composition. Here, we utilize the special quasi-random structure (SQS) supercells for hexagonal five-metal high-entropy borides (HEBs) and model them using quantum ab initio molecular dynamics (AIMD). The simulated P-V-T curves are in good agreements with the experimental results. Additional analysis of the theoretical pair distribution function (PDF) and equation of state (EoS) indicates that HEB materials can exhibit superior mechanical properties and remain stable under high pressure and high temperature (HPHT) conditions, making them suitable for potential extreme-environment applications.