In situ deformation and unfaulting of interstitial loops in proton-irradiated steels

Abstract Large interstitial Frank loops have been introduced into Fe-18 wt% Cr-14 wt% Ni alloy single-crystal foils by proton irradiation. These irradiated foils have then been deformed in a high-voltage electron microscope in order to examine dislocation interactions with the loops. Unfaulting of the loops by interaction with glide dislocations has been observed during in situ deformation. It has been shown that very few loops are eliminated during this deformation. The origin of the high stability of interstitial loops and its relation to irradiation creep are discussed in the light of the experimental findings.