Irradiation Hardening of Lam Steel Under High-Energy Fe Ion Irradiation

The irradiation resistance of low-activation martensitic steel has received considerable attention in the development of candidate structural materials for application in advanced reactors. This study has examined the effect of irradiation with 3.5 MeV Fe13+ ions on low-activation martensitic steel. The results have shown that the grain size of low-activation martensitic steel has been effectively refined by simultaneously adding Si content and reducing W content, showing more excellent mechanical properties and lower irradiation hardening rate, which provides a new reference for the design and optimization of low-activation martensitic steels. In addition, a significant enhancement of distortion and increased dislocations in the matrix have been identified by nanoscale characterization, where irradiation-induced dislocation loops result in irradiation hardening of the structural material. These findings have established the nature of irradiation hardening in low-activation martensitic steels and may provide a better understanding of irradiation damage mechanisms.