On the correlation between self-interstitial cluster diffusivity and irradiation-induced swelling in Fe–Cr alloys

Abstract

It is shown that the dependence of self-interstitial cluster diffusivity in Fe–Cr alloys on Cr concentration correlates with that of swelling in these alloys under neutron irradiation; namely, with increasing chromium concentration the cluster diffusivity first decreases and then increases. The origin of such behaviour lies in a relatively long-ranged, ∼1 nm, attractive interaction between Cr atoms and crowdions. The minimum diffusivity is realized for ∼11 at.% Cr, where all crowdions constituting the cluster interact with Cr atoms, but the interaction fields of different Cr atoms do not overlap.

Acknowledgements

This work was supported by the European Commission under the contract of Association between Euratom and the Belgian State and carried out within the framework of the European Fusion Development Agreement (EFDA), task TTMS-007. AVB acknowledges a research grant from the UK Engineering and Physical Sciences Research Council.