Texture contribution in grain refinement effectiveness of different routes during ECAP

Equal channel angular pressing (ECAP) is a processing tool for introducing grain refinement in wide range of materials. It has been proved that the effectiveness of the grain refinement depends on how the sample is rotated between passes. The increasing order of effectiveness for the routes has already been determined in fcc metals corresponding to die angles 90° and 120°. This order was found different for those die angles. Effect of processing routes on grain refinement effectiveness was studied by texture investigation of angular relation between crystallographic slip plane in the sample and the plane in where next shear deformation takes place. The angle θ between {1 1 1} planes in the aluminum sample and shear plane in the following ECAP pass was measured before each pass in the all the processing routes. It is shown that closer the θ angles to 70°, higher will be the grain refining effectiveness.