Molecular dynamics simulation of melting, solidification، remelting processes of aluminum

A molecular dynamics simulation study has been performed to investigate the solidification and remelting of aluminum using Sutton-Chen many body potential. Different numbers of atoms from 108 to 2048 atoms were considered to find an adequate size for the system. Three different cooling and heating rates, i.e. 1012 K/s, 1013 K/s and 1014 K/s, were used. The structure of the system was examined using radial distribution function. The melting and crystallization temperatures of aluminum were evaluated by calculating the variation of heat capacity during the phase transformation. Additionally, Wendt–Abraham parameters were calculated to determine the glass transition temperature. It is shown that the melting temperature of aluminum increases as the heating rate increases. During solidification, a crystalline or amorphous-like structure is formed depending on the cooling rate. Remelting of the amorphous solidified material is accompanied by crystallization before melting at heating rates <1014 K/s. The melting temperature also depends on the degree of structural crystallinity before remelting.