The possible appearance of non-perfect grain boundary dislocations in the boundaries of various materials was considered. Firstly, some of the theoretical treatments which permitted grain boundary dislocations and grain boundary structures to be described were reviewed. Emphasis was placed on the power of group theory for identifying non-perfect grain boundary dislocations. A derivation of the geometrical characteristics of interfacial dislocations was carried out in a simple manner for a number of typical examples. It was shown that grain boundary dislocations could be divided into 3 classes. These were perfect grain boundary dislocations, imperfect grain boundary dislocations and partial grain boundary dislocations. Experimental transmission electron microscopic evidence arising from diamond cubic structures was presented, and it was shown that imperfect and partial grain boundary dislocations played an important role in such materials.

A Theoretical and Experimental Study of Non-Perfect Grain Boundary Dislocations. L.Sagalowicz, W.A.T.Clark: Interface Science, 1996, 4[1-2], 29-45