Molecular-Dynamics Study of Self-Interstitial Diffusion in bcc-Iron

Abstract

Self-interstitial diffusion in α-iron is investigated using an embedded-atom-method potential and molecular-dynamics simulations. Curved Arrhenius plot is obtained for the temperature dependence of diffusion coefficients, which is well explained by the superposition of two transition processes among the two allotropic states of self-interstitial defects, the reformation of ⟨110⟩ dumbbell into another ⟨110⟩ configuration and one-dimensional solitonic propagation of a crowdion on ⟨111⟩ axis.