Using measurements of the geometric and crystallographic characteristics of approximately 104 triple junctions in a MgO polycrystal, the relative grain boundary energy was determined as a function of five macroscopic parameters. The relative energy of a particular grain boundary was inversely correlated with its frequency of occurrence. At all misorientations, grain boundaries with {100} interface planes had relatively low energies. For low misorientation angle grain boundaries, the results were consistent with the predictions of dislocation models. At high misorientation angles, the population and energy were correlated to the sum of the energies of the free surfaces that comprise the boundary.

The Relative Free Energies of Grain Boundaries in Magnesia as a Function of Five Macroscopic Parameters. D.M.Saylor, A.Morawiec, G.S.Rohrer: Acta Materialia, 2003, 51[13], 3675-86