Phase and Microstructural Selection in High Entropy Materials

Abstract

AbstractThe present chapter is intended to provide an in-depth analysis of alloy design strategies and phase formation rules for high entropy alloys (HEAs) and high entropy ceramics (HECs). Starting with classical Hume-Rothery rules for solid solution formation in binaries, the parametric approach, which has extensively been utilized for the design of HEAs, followed by CALPHAD and ab initio approaches, has been elaborated. CALPHAD approach, theoretically robust and computationally less intensive, shows more promise, although molecular dynamic simulations can provide a computationally intensive but better solution to the problem. Pettifor maps and design strategies for multicomponent ceramics have been discussed. Finally, the alloy design approaches for high entropy glasses have been elucidated in some detail.KeywordsAlloy designHume-Rothery rulesCALPHADDFTAIMDPettifor mapsSingle phaseMultiphase