Microstructures and boundary populations in materials produced by equal channel angular extrusion

Two aluminum alloys and two copper samples heavily deformed by equal channel angular extrusion (ECAE) were investigated. In these materials, microstructures and misorientation distributions were characterized in the transmission electron microscope. Deformation structures with a mixture of low- and high-angle boundaries were found in all samples. After a similar strain, low-angle boundaries were more frequent in copper than in the Al alloys. Boundary populations and spatial characteristics of different boundary types in ECAE-processed materials are compared with those produced by rolling.