The elastic-strain energy criterion of phase formation for complex concentrated alloys

An empirical method is developed, based on the calculated theoretical elastic-strain energy, to predict the phase formation and its stability for complex concentrated alloys. The method prediction quality is compared with the traditional empirical rules based on the atomic-size mismatch, enthalpy of mixing, and valence-electron concentration for a database of 235 alloys. The "elastic-strain energy vs. valence-electron concentration" criterion shows an improved ability to distinguish between single-phase solid solutions, and mixtures of solid solutions and intermetallic phases when compared to the available empirical rules used to date. The criterion is especially strong for alloys that precipitate the mu phase. The theoretical elastic-strain-energy parameter can be combined with other known parameters, such as those noted above, to establish new criteria which can help predict the design of novel complex concentrated alloys with the on-demand combination of mechanical properties.