Atomistic modelling of diffusion-controlled interfacial decohesion

This article reviews the atomistic aspects and the available atomistic modelling methods for studying diffusion-controlled interfacial decohesion. This comprises models for the atomic interaction that fall into two categories: materials-specific models that mostly contain some of the quantum-mechanical characteristics of the bonding, or generic simple pairwise or density-dependent interaction models. Furthermore, atomistic-simulation techniques and boundary conditions are discussed with regard to their importance for studying segregation phenomena and fracture. While reliable atomic-interaction models are still not generally available, it is shown that all the main simulation tools for the study of segregation, diffusion, and fracture along grain boundaries are available today. Consequently, a concerted effort to study all these effects in some model systems on the atomic scale and to combine the individual studies into a realistic model for the fracture process seems feasible.