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An ultrafine grained (UFG) aluminum sheet was produced using severe plastic deformation (SPD) by a process known as accumulative roll bonding (ARB). Electron Back Scattered Diffraction (EBSD) method and Transmission Electron Microscopy (TEM) were utilized for characterization of the subgrain and grain structures of the processed sheets. The results indicate that different mechanisms at different levels of strain lead to the gradual evolution of ultrafine or nanocrystalline grains. Grain fragmentation as well as the development of subgrains are the major mechanisms at the early stages of ARB. Strain induced transformation of low angle to high angle grain boundaries and formation of a thin lamellar structure occur at the medium level of strain. Finally, the progressive fragmentation of these thin lamellar structures into more equi-axed grains is the dominant mechanism at relatively high strains which results in grain size reduction to submicron scale.

Ultra-fine grained 1100 Al alloy was successfully produced by accumulative roll bonding (ARB) process. TEM investigation and SAD patterns showed that, after eight cycles of ARB, sheets were found to contain ultra-fine grains with high angle grain boundaries. The mechanical properties of the ARB processed (ARBed) 1100 aluminum alloy increased with increasing the number of ARB cycles. The elongation dropped abruptly at the first cycles. Wear properties were investigated using a pin on disk wear machine at ambient environment. Contrary to an expectation, the wear resistance of the ARBed Al alloy was less than the non-processed Al alloy. Morphologies of worn surfaces were studied by scanning electron microscope (SEM).

This work aims to investigate whether accumulative roll bonding (ARB) is an effective grain refinement technique for ultra-low-carbon steel strips containing 0.004% C. For this purpose, a number of ARB processes were performed at 500 °C, with 50% reduction in area of each rolling pass. It was found that both the ultimate grain size achieved, as well as the degree of bonding, depend on number of rolling pass and reduction of area as a whole. The mean grain size was obtained using AFM was about 130nm. The mechanical properties after rolling and cooling were obtained. Also, the fracture surfaces were studied by Scanning Electron Microscopy (SEM). It was concluded that metal's tensile strengths increased by 334% while the ductility dropped from a prerolled value of 50.5% to 2.6%. Effect of wire brushing on samples observed too. It increased on the wire brushed sheet for 7 HV. The rolling process was stopped when cracking of the edges became pronounced.

In this paper, Accumulative Roll-Bonding (ARB) process was used for producing the Al/Mg alloy multilayer structure composite materials with 1060Al sheet and MB2 sheet. The interface properties and fracture characteristics of Al/Mg cladding materials during ARB processes were observed by optical microscope, scanning electron microscopy and electronic tensile machine. The results showed that the resulting multilayer structure material of Al/Mg alloy had excellent bonding characteristics. And with ARB cycles increasing, the tensile strength was increased, and then dropped. Inter-diffusion of Al and Mg atoms occurred at the interface during the rolling process at 350°C. The thickness of diffusion layer is about 3.5-5.5μm. Shear fracture may occur at the interface of reaction products and Al during the peeling test process.