A new strategy to design eutectic high-entropy alloys using simple mixture method

Highlights: • A novel strategy to design/locate eutectic points in high entropy alloys was proposed. • The method was based on mixing enthalpy and binary eutectic composition. • Four new eutectic high entropy alloys were found and prepared following the simple idea/strategy. Eutectic high entropy alloys (EHEAs) hold promising industrial application potential, but how to design EHEA compositions remains challenging. In the present work, a simple and effective strategy by combining mixing enthalpy and constituent binary eutectic compositions was proposed to design EHEA compositions. This strategy was then applied to a series of (CoCrFeNi)M_x (M = Nb, Ta, Zr, Hf) HEAs, leading to the discovery of new EHEAs, namely, CoCrFeNiNb_0.45, CoCrFeNiTa_0.4, CoCrFeNiZr_0.55 and CoCrFeNiHf_0.4. The microstructure of these new EHEAs comprised of FCC and Laves phases in the as-cast state. The experimental result shows that this new alloy design strategy can be used to locate new EHEAs effectively.