Low angle tilt boundary migration coupled to shear deformation

The shear stress induced migration of planar < 100 > tilt grain boundaries in Al bicrystals was observed to be perfectly coupled to the lateral translation of grains. Boundaries with misorientations of 10.5 degrees and 12.0 degrees on one side of the misorientation range (0-90 degrees) and 81.0 degrees and 81.1 degrees on its other side move in opposite directions under the same applied external stress. The measured ratios of the normal to the lateral motion comply perfectly with the coupling factors of a recently proposed model of boundary motion. (c) 2006 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.