A comparative study on temperature dependent diffusion coefficient of liquid Fe

Abstract

The self-diffusion coefficients, D, of liquid Fe at different temperatures have been investigated using hard sphere (HS) theory and universal scaling laws (USLs). Inter-ionic interaction is derived from both pseudopotential proposed by Brettonet–Silbert (BS) and many body potential obtained from embedded atom method (EAM). Temperature dependent effective HS diameter, σ(T), and excess entropy, Sex, are the premier ingredients of the study. The former ingredient is calculated using both variational modified hypernetted chain, VMHNC, integral equation theory and Linearized Weeks–Chandler–Andersen, LWCA, thermodynamic perturbation theory together with an empirical relation of Protopapas et al. (1973) [2] whereas the later one is calculated using VMHNC theory alone, with BS and EAM potentials. We observe that D increases with increasing temperatures. The obtained results are compared with those predicted by Protopapas et al. The comparison suggests that USL of Dzugutov and HS theory with BS potential are better choices to predict D(T) of liquid Fe.