Evidence was presented for finite and/or imperfect low-angle grain boundaries, and their associated long-range stress fields, which formed during the hydrothermal growth of berlinite crystals on multiple-seed arrays. These defective boundaries originated at angularly misaligned junctions between adjacent seeds, as a result of the failure of some component sets of dislocations to propagate epitaxially into the new growth. Since they lacked a full complement of dislocations, the newly-grown boundaries could be imperfect and could generate long-range stresses; thus leading to fracture and/or plastic flow.

R.C.Morris, B.H.T.Chai: Journal of Crystal Growth, 1998, 191, 108-12