A novel nano-spaced coherent FCC1/FCC2 eutectic high entropy alloy.

• A novel nanostructured Fe 39 Cr 39 Ni 14 C 8 eutectic high entropy alloy was developed. • The rapid solidification alloy exhibits a typical fully lamellar FCC1/FCC2 eutectic structure. • FCC1 phase has a unique cube-cube coherent relationship with FCC2 phase. • Its high hardness and high yield strength originate mainly from the phase interface strengthening. A novel nanostructured Fe 39 Cr 39 Ni 14 C 8 eutectic high entropy alloy (EHEA) was developed by rapid solidification. Detailed characterization reveals that the rapidly solidified Fe 39 Cr 39 Ni 14 C 8 EHEA shows a nano-lamellar structure consisting of alternative FCC1 (∼120 nm in width) and FCC2 (∼80 nm) phases with a coherent relationship and possesses a high hardness of 463HV (∼4.5 GPa) and a high yield strength of 1.45GPa. They are mainly attributed to the unique ultrafine eutectic structure. This finding would shed new light on the development of FCC1/FCC2-nanostructured EHEAs with excellent mechanical properties. [ABSTRACT FROM AUTHOR]