Spinodal decomposition and radiation damage of a FeCuMnNi high-entropy alloy

The precipitation of Cu-rich phases during the irradiation process will reduce radiation resistance in Fe-Cu-Mn-Ni reactor pressure vessel steels. Therefore, high-entropy alloys with excellent radiation resistance are expected to replace reactor pressure vessel steels and become structural materials for fusion and generation IV fission reactors. This study investigated the phase formation, spinodal decomposition tendency, and radiation resistance of the FeCuMnNi high entropy alloy using a multi-scale method. The results show that FeCuMnNi alloy has a dualphase face-centered-cubic structure. Here, for the first time, we found that the precipitation phase of the FeCuMnNi high-entropy alloy during the irradiation process is a Mn-rich phase rather than a Cu-rich phase found in conventional Fe-Cu-Mn-Ni reactor pressure vessel steels. Mn separates from the Cu-Mn-rich phase and forms Fe-Mn-Ni clusters with a Fe-Ni phase during irradiation.