Abstract
The current research utilized a unique material design of nanostructured medium-entropy alloys with numerous defect sinks, offering great potential to withstand extreme conditions in advanced nuclear reactors. Hence, this work examined oxide dispersion strengthened (ODS)-NiCoFeCr alloy with nanosized grains after Ni +2 irradiation at 580 °C up to a peak damage of 101 displacements per atom. The alloy showed insignificant hardening and no detectable void formation following irradiation. Also, oxide nanoprecipitates and grains exhibited a limited growth of ~2 and ~5 nm, respectively, with irradiation. The volume-averaged dislocation length density remained on the order of ~10 14 m −2 , and the mean dislocation length showed a slight increase from 89 to 97 nm, with irradiation. A lower level of radiation-induced segregation was observed at the grain boundaries; however, the extent of RIS depended on the misorientation angles, with a maximum at 45.7° among the grain boundaries analyzed.