Effect of Additional Alloying Elements on Microstructure and Properties of AlCoCrFeNi High Entropy Alloy System: A Comprehensive Review

High entropy alloys (HEAs), known for their multi-principal element composition, have attracted considerable interest in light of their unique mechanical and thermal properties. Among them, the AlCoCrFeNi HEA system has shown promising characteristics, but the influence of additional alloying elements on its performance remains a crucial area of study. This comprehensive review investigates the effects of incorporating supplementary elements into the core AlCoCrFeNi system on its microstructure and various properties. Furthermore, it explores how these alterations in microstructure impact the mechanical properties, corrosion and wear behavior of the HEA, emphasizing the potential to customize these properties through strategic alloying additions. Additionally, the review examines how varying the amounts of constituent elements in the AlCoCrFeNi system, without adding additional elements, influences the microstructure and phases formed, with the help of phase diagrams. This review offers valuable insights to researchers and engineers aiming to optimize AlCoCrFeNi HEAs for specific applications.