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

• Carbon diffusion in face-centered cubic iron is studied by molecular-dynamics simulations.
• The Modified Embedded Atom Method (MEAM) potential for the Fe–C system by Lee is used.
• Diffusion is studied for carbon concentrations of 0.6, 1.1 and 1.4 wt%.
• Based on an Arrhenius approach the results are compared to empirical models.

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.

Figure optionsDownload as PowerPoint slide