Both ab initio and empirical potential based molecular dynamics and static calculations were used to parameterize a model which accounted for the mobility of self-interstitial clusters and small dislocation loops in Fe–Cr alloys, depending upon the Cr content. In particular, the interval of 5 to 15%Cr - corresponding to the typical concentration of Cr in ferritic/martensitic steels - was considered. The mobility of self-interstitial clusters and small dislocation loops was found to be strongly reduced in the presence of Cr due to attractive interaction between self-interstitials and Cr atoms, whereas Cr-rich precipitates acted as repulsive obstacles. The results obtained allow the experimental trend of swelling measurements in neutron and high-energy electron irradiated Fe–Cr alloys to be interpreted and explained.

Characterization of Dislocation Loops and Chromium-Rich Precipitates in Ferritic Iron–Chromium Alloys as Means of Void Swelling Suppression. D.Terentyev, P.Olsson, L.Malerba, A.V.Barashev: Journal of Nuclear Materials, 2007, 362[2-3], 167-73