Melting mechanisms of Nb(111) plane with molecular dynamics simulations

Using the modified analytic embedded-atom method, the premelting and melting process of the low-index plane of niobium (111) is studied with molecular dynamics simulations. The physical properties of this plane, including the layer atomic density function, the layer structure factor and the radial distribution function, are calculated in order to systematically investigate the complex microstructure evolution of the (111) plane with temperature. The results indicate that there exists a premelting phenomenon on the (111) surface of niobium at lower temperature and it has melted entirely at some temperature below the corresponding melting point of the prefect crystal. In addition, the premelting atomic fraction of this plane is fitted with the corresponding temperature to obtain the surface premelting activation energy which is able to estimate the premelting phenomena and the disordering progress of the plane.