Evaluating the properties and applications of high entropy borides, nitrides and carbides

This study investigates the unique properties and prospective uses of high entropy ceramics, with special emphasis on borides (HEBs), carbides (HECbs), and nitrides (HENs). Being an innovative material, these ceramics consist of multiple principal elements chemically harmonized under severe lattice distortion and large configurational entropy, which control their unique thermal stability, mechanical hardness, and wear resistance. The principal objective of the research is to analyze the intrinsic characteristics of these high entropy systems and determine their applicability in ultra-high-temperature environments. Through a comprehensive literature review, focusing on critical assessment of experimental and computational works, the research discovered the prospective performance of HEBs, HECbs, and HENs in severe environments like aerospace, defense, and nuclear applications. Nevertheless, poor oxidation resistance, low fracture toughness, and scalability of synthesis are the unresolved challenges affecting HECs. The research recommends developing industrially viable synthesis methods like self-propagating high-temperature synthesis (SHS), flame spray pyrolysis, as well as combining machine learning with CALPHAD and DFT to design and develop more smart production of robust HECs with improved structural and functional performance. The study further recommends that future research should inquire not only the structural roles of HECs but also their functional applications in energy storage, electronic barriers, and functional coatings, thereby expanding the impact of high entropy ceramics in emerging technologies. The next wave of research should aim at increasing the oxidation tolerance, develop industrial viable synthesis pathways, and expand the multifunctional applications of HECs in harsh conditions.