Radiation damage process of vanadium and its alloys during electron irradiation

Abstract

Microstructural change and the migration energies of point defects in V, V4Ti4Cr and oxide dispersion strengthened vanadium were examined by high voltage electron microscopy. Irradiation was performed up to 7.2 dpa at room temperature to 773 K. To protect the specimens from surface contamination, some specimens were coated with Ti and Cr by the evaporation process. During irradiation of low dose, interstitial-type dislocation loops were initially nucleated and grown. Micro-voids were observed in oxide dispersion strengthened vanadium at 723 K. The migration energies of interstitials and vacancies were estimated from the number density and the growth rate of the loops, as a function of temperature. The microstructure change is explained by the effect of the interaction between impurities and solute atoms.