A molecular-dynamics study on carbon diffusion in face-centered cubic iron

Molecular-dynamics calculations targeted at the diffusion of carbon in γ-iron were performed using the Modified Embedded Atom Method (MEAM) interatomic potential by Lee. The diffusion coefficients were calculated at different temperatures and carbon concentrations. A temperature-dependence of the diffusion coefficient according to the Arrhenius law was assumed. By doing so, activation energies as well as pre-exponential factors for different carbon concentrations were derived from the diffusion coefficients and compared to experimental values. Good agreement was reached for the activation energies while the calculated pre-exponential factors differ from experimental values.