Research Article Accumulative Roll Bonding of Pure Copper and IF Steel Saeed Tamimi, 1,2 Mostafa Ketabchi, 1 Nader Parvin, 1 Mehdi Sanjari, 3 and Augusto Lopes 4 1 Mining and Metallurgical Engineering Department, Amirkabir University of Technology, Tehran 15875-4413, Iran 2 Department of Mechanical Engineering, TEMA, University of Aveiro, 3810-193 Aveiro, Portugal 3 Mining and Materials Engineering Department, McGill University, Montreal, QC, Canada H3A 0E8 4 Departamento de Engenharia de Materiais e Ceramica, CICECO, University of Aveiro, 3810-193 Aveiro, Portugal Correspondence should be addressed to Saeed Tamimi; saeed.tamimi@gmail.com Received 13 June 2014; Revised 20 August 2014; Accepted 24 August 2014; Published 23 September 2014 Academic Editor: Mohammad Reza Toroghinejad Copyright © 2014 Saeed Tamimi et al. Tis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Severe plastic deformation is a new method to produce ultrafne grain materials with enhanced mechanical properties. Te main objective of this work is to investigate whether accumulative roll bonding (ARB) is an efective grain refnement technique for two engineering materials of pure copper and interstitial free (IF) steel strips. Additionally, the infuence of severely plastic deformation imposed by ARB on the mechanical properties of these materials with diferent crystallographic structure is taken into account. For this purpose, a number of ARB processes were performed at elevated temperature on the materials with 50% of plastic deformation in each rolling pass. Hardness of the samples was measured using microhardness tests. It was found that both the ultimate grain size achieved, and the degree of bonding depend on the number of rolling passes and the total plastic deformation. Te rolling process was stopped in the 4th cycle for copper and the 10th cycle for IF steel, until cracking of the edges became pronounced. Te efects of process temperature and wire-brushing as signifcant parameters in ARB process on the mechanical behaviour of the samples were evaluated. 1. Introduction Recently, much attention has been directed to ultragrain refning of metallic materials, where the grain size is reduced to less than one micrometre. According to Hall-Petch rela- tionship, it is expected that ultrafne grain (UFG) structure would result in higher strength [1, 2]. Producing high strength materials, particularly without alloying, is very important in economical point of view. Severe plastic deformation (SPD) techniques have been known in the last decades as efective methods to produce UFG materials. Te efciency of traditional SPD techniques has been carried out such as equal channel angular pressing (ECAP) and high-pressure torsion (HPT) for grain refnement of a number of metallic materials, for example, [3, 4]. It has been shown that the UFG microstructure can be achieved using these methods; however, the typical sizes of the samples deformed by ECAP and HPT are small [5]. Furthermore, these types of SPD processes require special and/or expensive equipment. In recent years, a number of alternative SPD technologies have been developed, including equal channel angular rolling, cyclic bending, and accumulative roll bond- ing (ARB) in which the mentioned limitations were partially omitted [5, 6]. Tese SPD processes have potential to be adopted by the industry to produce UFG materials in the form of large sheets, due to their possibility as continuous processes. Saito et al. developed the ARB process for the frst time in which SPD strategies are applied in a simple rolling process [7, 8]. Tis SPD process has then been used to fabricate UFG microstructures in various engineering materials and the efect of UFG structure on their mechanical properties have been studied, for example, [9–12]. However, there is a lack of study on the comparison of efcacy of ARB on the microstructure and its induced mechanical response of two diferent crystallographic structure materials. Tis study focuses on the ARB process in IF steel and pure copper sheets. Te process parameters such as plastic deformation, processing temperature, and sample preparation factor are Hindawi Publishing Corporation International Journal of Metals Volume 2014, Article ID 179723, 9 pages http://dx.doi.org/10.1155/2014/179723