An Analysis on the deformation of pure copper during multi-pass Equal Channel Angular Extrusion

Nanomaterials are produced by subjecting materials to severe plastic deformation (SPD) which has widely emerged as a technique for grain refinement in Al, Cu, Ti, Mg alloys with improved mechanical properties. Equal Channel Angular Pressing (ECAP) is one of the attractive SPD techniques because it offers potential for high strain rate super plasticity by effective grain refinement from macro gained structure to the level of sub-micron or nano-scale. The aim of this paper was to study the deformation homogeneity of pure copper during multi-pass equal channel angular extrusion. The Finite Element Modeling of ECAP is done in metal forming software FORGE. The experiment is performed in cold working conditions though route C with channel angle Phi = 90(0) and having different friction conditions. The evolution of equivalent strain is analysed for the deformed billet under different processing parameters upto 5 passes. Also, variation in extrusion force, energy and stresses are studied for the considered conditions. It is established through simulations that number of passes and friction plays significant role in strain homogeneity and changes in vonmises stresses. The study helps in developing ultra-fine grain materials for automobile and aerospace applications. (C) 2014 Elsevier Ltd.