Lattice dynamics analysis of the thermal properties of liquid iron

In this paper, the embedded atom method potential and Johnson potential are applied to calculate the thermal properties of liquid iron with an emphasis on a wide rage of temperatures and pressures. The results show that the liquid iron self-diffusion coefficient increases with increasing temperature and decreases with increasing pressure. The calculated self-diffusion coefficient is in good agreement with Protopapas' hard-sphere model at atmospheric pressure. According to the simulation results, we can get the Arrhenius equation between diffusion coefficient, temperature and activation energy. Increasing pressure enlarges the liquid iron activation energy and reduces the movement of atoms in liquid iron. Liquid iron thermal conductivity is computed using non-equilibrium molecular dynamics simulation and the simulation results are consistent with Pottlacher's experimental results with acceptable uncertainty in the 1535 - 2700 K temperature range.