The Effect of a Grain Boundary on Deformation in an Aluminum Bicrystal with a Common Tensile Axis of [100

Abstract

The effect of a grain boundary on deformation has been examined using an aluminum bicrystal specimen composed of crystals having a common tensile axis of [100] by the measurement of orientation change with the electron backscatter diffraction technique. After deformation to a strain of 20%, the crystal rotation axis (CRA) map, which provides the orientation distribution of crystal rotation axes relative to the initial crystal orientations, reveals areas affected by the grain boundary. The thickness of the affected zone was 100 μm in one crystal and 150 μm in the other. In both crystals, the crystal rotation axis relative to the initial crystal orientation differed between the affected zone and the crystal interior. In the crystal interior, two slip systems showed a higher activity than the other slip systems, whereas in the affected zone, three or four slip systems were more active than the other slip systems. The CRA map showed that the width and shape of the affected zones across the grain boundary were not symmetrical with respect to the grain boundary.