An EAM simulation of the alpha - gamma iron interface

Abstract

The embedded atom method was used for the design of an atomic potential model for the simulation of the alpha - gamma iron interface. The model takes the form of three cubic expressions covering different ranges, and is normalized to give equilibrium to the two-body potential as well as to the embedding function at the perfect lattice configurations of both the alpha and gamma phases. The model yields good results for surface energies and the vacancy formation energy. Simulations were carried out for alpha - gamma interfaces with the Nishiyama-Wasserman orientation relationship. Interface energies were calculated for interfaces without structural ledges, with monoatomic ledges and with triatomic ledges with results close to the experimental values. The relaxation behaviour of the lattices from their initial configurations was also studied, and it was found that most of the relaxation occurs along the atomic habit planes instead of perpendicular to them. No major effect of different boundary conditions on the lattice relaxation and the interface energy was observed.