Development of damage structure in 16Cr–4Al ODS steels during electron-irradiation

Development of irradiation damage structure in ODS ferritic steels was studied by means of in-situ observation of HVEM up to 10 dpa at 773 K. In this study, standard ODS steel, Fe–16Cr–4Al–2W–0.35Y2O3 and other of steels including Zr or Hf were examined. During electron-irradiation, preferential nucleation of dislocation loops was observed on oxide particles. In Hf- or Zr-added steels dislocation loops showed a low growth rate and a low number density compared with the standard steel. These results are explained by the sink effect at the interface between the matrix and oxide particles.