Grain boundary

Interface between crystallites in a polycrystalline material

In materials science, a grain boundary is the interface between two differently oriented grains, or crystallites, of the same phase in a polycrystalline material. Grain boundaries are two-dimensional defects in the crystal structure, and tend to decrease the electrical and thermal conductivity of the material. Most grain boundaries are preferred sites for the onset of corrosion and for the precipitation of new phases from the solid.

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