Mechanical and energetical analysis of molecular dynamics simulations of dislocation–defect interactions

In this paper, we present a method of analysis on the continuum scale of molecular dynamics simulations of dislocation–defect interactions. It is shown how the applied work can be decomposed into its elementary components: the elastic strain energy, the dissipated work against the Peierls stress and the curvature energy needed to enable the dislocation, pinned by the defect, to bow out. While the dissipated work is entirely extracted from the system in molecular statics, the elastic and curvature energies contribute to a large increase in the internal energy. The curvature energy is evaluated and compared with predictions of the line tension model. This analysis allows the calculation of the dislocation–defect interaction energy and the determination of the predominant features in the unpinning process.