Recent advances in high-entropy carbide ultra-high temperature ceramics: Synthesis, properties, and applications

High-entropy carbides (HECs) have emerged as a class of advanced ultra-high temperature ceramics with remarkable potential for applications in extreme environments. Their unique combination of high melting points, excellent thermal stability, and exceptional mechanical properties makes them promising candidates for aerospace, nuclear, and cutting-edge technologies. This review discusses the latest advances in the synthesis, properties, and applications of HECs, providing insights into the composition, structure–property relationships, and processing techniques. A detailed analysis of the state-of-the-art fabrication methods, including powder metallurgy, spark plasma sintering, and chemical vapor deposition, is presented. The study also examines the correlation between the intrinsic properties of HECs, such as oxidation resistance, thermal conductivity, and mechanical strength, with their component elements. Furthermore, recent developments in their application in high-temperature structural materials, thermal protection systems, and energy conversion devices are critically reviewed. Quantitative comparisons of material performance in terms of phase stability, hardness, and thermal resistance are also presented to highlight the potential and limitations of these advanced materials. Overall, the versatility and adaptability of high-entropy carbides position them as frontrunners for future high-performance applications in extreme conditions.