High Entropy Alloys Mined From Phase Diagrams

Abstract: High entropy alloys (HEA) show promise as a new type of high-performance structural material. Their vast degrees of freedom provide for extensive opportunities to design alloys with tailored properties. However, the compositional complexities of HEAs present great challenges for alloy design. Current approaches have shown limited reliability in accounting for the compositional regions of single solid solution and composite phases. We present a phenomenological method, analyzing binary phase diagrams to predict HEA phase formation on the hypothesis that the structural stability of HEAs is encoded within. Accordingly, we introduce a small number of phase-diagram inspired parameters and employ machine learning to partition the formation region of 500+ reported HEA compositions. The model achieved a single phase HEA prediction rate >80 %. To validate our method, we demonstrated the capability of this method in predicting HEA solid solution phases with and without intermetallics in 30 randomly selected complex compositions, with a success rate of 77 %. The presented efficient search approach with high predictive capability can be exploited to complement computation-intense methods in providing a powerful platform for the design of high entropy alloys.