Characteristics of coincident site lattice grain boundaries developed during equal channel angular pressing of magnesium single crystals

Distributions of near-coincidence grain boundaries that occur during equal channel angular pressing in magnesium single crystals at 503 K are investigated. The coincidence boundaries with the [0 0 0 1] misorientation axis are frequent in the sample after passage of the shear plane and recrystallization. In contrast, twin boundaries dominate in the end parts of the samples. Existence of a 30 degrees peak in the misorientation angle distribution is explained by a relatively high frequency of Sigma 13a boundaries and partially by the appearance of Sigma 15a boundaries. (C) 2010 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.