Study and Comparison of Simple Shear Extrusion and Accumulative Roll Bonding Processes in Improving the Mechanical and Structural Properties of Copper

Techniques of severe plastic deformation have been of continual interest in the production of novel metallic microstructures. Among these, accumulative roll bonding and simple shear extrusion have been extensively used in modern industry. In severe plastic deformations, applied strains have higher values than usual forming methods. Accumulative roll-bonding (ARB) and simple shear extrusion (SSE) processes are two severe plastic deformation processes capable of developing nanostructures. In this research, pure commercial copper was processes with ARB and SSE processes to obtain nanostructure and improve its structure, strength and hardness. Five passes of extrusion and seven passes of rolling were applied on the specimens with the same conditions. After preparing the specimens using both methods, mechanical and structural analyses were performed to evaluate the properties. Mechanical properties were measured using standard tensile and hardness tests. The results show that hardness, yield strength and ultimate tensile strength of the extruded and rolled specimens are increased by increasing the number of cycles. It was concluded that mechanical and structural properties of the specimens produced under ARB conditions appear to be better than SSE process. The layers structures were also studied by optical microscopy.