AccumEx - A New SPD Technique for Fabricating Lamellar Materials

Accumulated extrusion is a novel plane strain compression technique, akin to the process of accumulated roll bonding, designed to produce ultrafine grained lamellar materials. AA1050 CP-Al processed by AccumEx displayed a grain refinement from 17 μm to 1.8 μm after 2 passes (equivalent strain of 3.2) with an increase in tensile strength of ≈70%. A comparative study with the conventional equal channel angular extrusion technique demonstrated that the former displayed a higher fraction of high angle grain boundaries with very similar trend of grain refinement. Up to now, extrusions up to 8 passes have been performed.