This research employs the atomically flat grain-boundary facets which form as the result of solute segregation in bismuth-doped copper as a model system with which to study the relationship between grain boundary composition and structure and the evolution of structure in a two component alloy. The principal experimental tools are conventional and high-resolution transmission electron microscopy (HREM). The approach is to identify crystallographic orientations of the facet planes in each of two abutting grains for a grain pair of specific misorientation, and then determine the location of the bismuth atoms in the facets by HREM. These results are compared to atomistic calculations. Evolution of facet types is examined as a function of time and annealing temperature. %%% This research provides important information about the atomic-scale structure and chemistry of segregation at grain boundaries. Grain boundaries play an important role in determining the physical properties of polycrystalline materials.
