Irradiation stability and induced ferromagnetism in a nanocrystalline CoCrCuFeNi highly-concentrated alloy

Abstract

In the field of radiation damage of crystalline solids -- where new highly-concentrated alloys (HCAs) are suitable candidate materials for next generation fission/fusion reactors -- outstanding radiation tolerance has been recently recorded. Despite the preliminarily reported extraordinary properties, the mechanisms of degradation, phase instabilities and decomposition of HCAs are still largely unexplored fields of research. Herein, we investigate the response of a nanocrystalline CoCrCuFeNi HCA to heavy ion irradiation in the temperature range from 293 to 773 K. The results led to the identification of two regimes of response to irradiation: (i) in which the alloy was observed to be tolerant under extreme irradiation conditions and (ii) in which the alloy is subject to matrix phase instabilities. The formation of FeCo monodomain nanoparticles under these conditions is also reported for the first time, which may have promising applications in new technological areas such as spintronics.