The molecular dynamics (MD) simulations were applied to the melting transition of the BCC metal Fe using the modified embedded atom method (MEAM) potential proposed by Jin et al. [Appl. Phys. A120 (2015) 189], and the newly derived formulas were adopted to calculate the forces acting on atoms in the MD simulations. We first determined the structural and energetic properties of the effectively infinite solid with no boundaries, and then investigated the Fe samples with low-index surfaces, namely Fe(100), Fe(110), and Fe(111). The simulations show that as the temperature increases, the (111) surface firstly disorders, followed by the (100) surface, while the (110) surface remains stable up to the melting temperature. The disorder phenomenon diffuses from the surface to the entire block, and as the density of atoms on the surface decreases, the effect of the premelting phenomenon also increases, being most pronounced on Fe(111) which has the lowest surface density. This conclusion is in line with the behavior found for BCC metal V in the previous simulation study.
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