Theoretical and computational modeling studies on high-entropy alloy coatings

High-entropy alloys (HEAs) represent a class of materials with exceptional mechanical and tribological properties, making them ideal for advanced coating applications. This work presents a comprehensive exploration of HEA coatings using theoretical and computational models, incorporating molecular dynamics (MD) simulations, density functional theory (DFT), and dislocation analysis. Key findings demonstrate the superior performance of HEA coatings in improving wear resistance, reducing friction, and enhancing mechanical strength compared to pure metal substrates. MD simulations reveal that HEA coatings, such as those comprising AlCoCrFeNi and FeCoNiTi, significantly mitigate crack propagation, lower dislocation density, and improve hardness by inducing atomic-scale distortions and solid solution strengthening. Nanoindentation and wear tests further highlight reduced plastic deformation and wear volume loss in HEA-coated materials. Furthermore, DFT calculations provide insights into the electronic interactions at interfaces, emphasizing the role of localized covalent bonding, charge redistribution, and orbital hybridization in reinforcing heterojunction stability and wear resistance. Additionally, HEAs exhibit great potential for catalytic applications, with enhanced electron transport and active sites attributed to their multi-elemental configuration. Incorporating elements such as Mo improves catalytic performance through increased d-orbital contributions and reduced band gaps. This integrative approach combining MD and DFT modeling underscores HEA coatings' potential for applications in tribology, catalysis, and structural reinforcement.