This paper reviews findings on the anisotropy of the grain boundary energies. After introducing the basic concepts, there was a discussion of fundamental models used to understand and predict grain boundary energy anisotropy. Experimental methods for measuring the grain boundary energy anisotropy, all of which involved application of the Herring equation, were then briefly described. The next section reviews and compares the results of measurements and model calculations with the goal of identifying generally applicable characteristics. This was followed by a brief discussion of the role of grain boundary energies in nucleating discontinuous transitions in grain boundary structure and chemistry, known as complexion transitions. The review ends with some questions to be addressed by future research and a summary of what was known about grain boundary energy anisotropy.

Grain Boundary Energy Anisotropy: a Review. G.S.Rohrer: Journal of Materials Science, 2011, 46[18], 5881-95