Structural and atomic displacement evaluations of Aluminium nanoparticle in thermal annealing treatment: an insight through molecular dynamic simulations

Abstract

:In the present study, Molecular Dynamic (MD) simulations were applied to uncover the phase transition of Aluminium (Al) nanoparticles in annealing treatment. Parameters and properties, like potential energy, Mean Square Displacement (MSD), diffusion coefficient, crystal style and Radial Distribution Function (RDF), were discussed in the following article. In the linear heating stage (stage one), it was confirmed that the melting behaviour started at 960 K and ended at 1038 K. With the process of melting, the diffusion of Al atoms was accelerated from shell to core. In the thermostat stage (stage two), lots of bulges appeared due to the high kinetic energy and limited atomic interactions. Those bulges spread just like waves. In the slowly cooling stage (stage three), we observed the supercooling phenomenon. The solidification of melted Al nanoparticle started at 540 K, which was much lower than its melting temperature. Comparing with the original one, the cross-section of annealed nanoparticle showed some penetrating defects.