A comprehensive review: Discussed the effect of high-entropy alloys as reinforcement on metal matrix composite properties, fabrication techniques, and applications

In research, high-entropy alloy-reinforced metal matrix composites (HEAs-MMCs) have attracted academicians, researchers, and scientists to achieve extraordinary properties unobtainable by ceramic-reinforced metal matrix composites. HEAs have potential to improve the properties of weak metal matrices due to their superior properties such as high strength, stability in high-temperature applications, improved corrosion, and wear resistance. HEA has novel properties over conventional alloy system including exceptional performance at high temperatures, improved mechanical properties in cryogenic environments and high strength with ductility. The rapidly evolving needs of industries require high-performance materials, and HEA-MMCs are suitable for fulfilling the demands of newly established application fields.In this review article, the author discusses fabrication methods, microstructural evolution, mechanical, wear, thermal, electrical and corrosion properties, effects of heat treatment and strengthening mechanisms of HEA-MMC materials. HEA-MMC is suitable for large-scale and mass production with complex and precise HEA-MMC parts fabricated by commercialization of the casting process and additive manufacturing technology. The core-shell structure is formed by the diffusion action between the matrix and the reinforced and acts as a transition layer, leading to an improvement in mechanical properties. Finally, from the strengthening mechanisms, it was concluded that fine grain strengthening, Orovan strengthening and coefficient of thermal expansion (CTE) imbalanced strengthening mechanisms were more effective than others in improving properties. At the end of the review paper, the main importance, applications, challenges and perspectives of HEAs-MMCs are discussed, which will help the development of advanced materials with improved performance that can increase progress and innovation in the scientific community.