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° peak in the misorientation angle distribution is explained by a relatively high frequency of Σ13a boundaries and partially by the appearance of Σ15a boundaries.