Exploring the Influence of Lattice Distortion on the Properties of High Entropy Carbides (HECs) with Carbon and Metal Point Defects Using First Principles Study

High Entropy Carbides (HECs) have been predicted the selection of candidate compositions with the phase stability from an entropy-forming-ability (EFA) descriptor from first principle. The predicted compositions are applied to disordered refractory five metal carbides, experimentally synthesized as rocksalt structure and measured their mechanical properties. We report in this work the results of DFT calculations that were carried out to explore the degree to which properties of high entropy carbides containing different five-atom combinations from the elements Hf, Nb, Mo, Ta, Ti, V, W, and Zr can be related to the properties of their respective Transition Metal (TM) binary compounds. Using Density Functional Theory calculations, we aim to investigate the effect of lattice distortion on the properties of HECs and their respective Transition Metal Carbides (TMCs : HfC, NbC, TaC, TiC, ZrC, MoC, VC and WC) with a focus on their sensitivity to point defects. This research primarily explores the bulk modulus of HECs and their TMCs by introducing carbon and metal vacancy point defects, and determining to what extent these properties can be predicted based on their respective TMCs compositions. Understanding these aspects is crucial for guiding the design and optimization of HECs. With an emphasis on the effect of lattice distortion on point defect energetics, we anticipate that this comprehensive study will provide valuable insights into how point defects influence the properties of HECs.