Recent advances in magnetron-sputtered high entropy ceramic coatings

High Entropy Ceramic (HEC) coatings represent a novel class of advanced materials distinguished by their complex, multi-elemental compositions, typically comprising five or more metal nitrides, oxides, borides, or carbides in near-equimolar ratios. These coatings were engineered for applications requiring exceptional thermal stability, hardness, corrosion resistance, and other enhanced surface properties, often surpassing the performance of conventional ceramics. Recent research has increasingly focused on the application of HECs as surface coatings via magnetron sputtering. Such coatings have demonstrated improved surface performance and mechanical properties, making them promising candidates for a range of demanding applications. This review discusses and analyzes the microstructural characteristics and mechanical behavior of surfaces coated with magnetron-sputtered HECs. Specifically, it explores the influence of magnetron sputtering on grain structure, phase distribution, yield strength, hardness, tribological performance, and corrosion resistance. The review further highlights various emerging applications of HEC coatings and provides a comprehensive overview of current research trends, offering valuable insights for future studies.