The structure of high-angle grain boundaries

Abstract A coincidence model of high-angle grain boundaries can be extended to include deviations from coincidence. The generalised boundary has a terraced structure, corresponding to the densely packed planes in the coincidence lattice, and a superimposed dislocation network, corresponding to a sub-boundary in the coincidence lattice. This model is a natural extension of previous dislocation models and models based on coincidence relationships. The model explains many of the observed properties of grain boundaries and should have wide validity for the cubic system.