Molecular dynamics simulations were made of the effect of Cr upon the diffusion of single, di- and tri-interstitials in Fe–10%Cr alloys. Two Finnis-Sinclair-type potentials were used to model the Fe–Cr alloys, which alternately describe Cr as under- or over-sized in body-centred cubic Fe. In general, the diffusivity of the single interstitials and di- and tri-interstitial clusters was reduced in the Fe–10%Cr alloys, irrespective of interatomic potential, although the underlying mechanism was different. When Cr was undersized, interstitial diffusion was retarded through a trapping mechanism associated with bound Cr-interstitial (mixed dumb-bell) complexes, whereas oversized Cr atoms retard interstitial diffusion by enhancing the rotation frequency away from one-dimensionally mobile <111> interstitial dumb-bell configurations.

Molecular Dynamics Simulations of Point Defect Interactions in Fe-Cr Alloys. K.L.Wong, J.H.Shim, B.D.Wirth: Journal of Nuclear Materials, 2007, 367-370[1], 276-81