Molecular dynamics simulation of stress field around edge dislocations in Aluminum

Selection of potential functions is a very important step in molecular dynamics (MD) simulations due to its effects of the preciseness and reliability of the simulations. Different potential functions have been developed for atomistic simulations of materials and the embedded atom method (EAM) can be considered as the most successful class of potential function with acceptable accuracy and performance. Reliability of a potential function is determined by comparing simulation results with basic experimental results or physical and mechanical models. In the current work, the calculated stress tensor around an edge dislocation, based on the isotropic and anisotropic continuum models, was chosen as the basis for evaluations of some notable EAM potential functions developed for Aluminum. Qualitative and quantitative comparisons between the results of MD simulation with four selected potential functions and the continuum models were made. Every component of the stress tensor was studied separately and the potential functions were ranked according to their accuracy and the appropriate potential function was introduced. These findings can be considered as a basis for simulation of the different aspects of mechanical behavior of metallic materials.