Manufacturing of Al–Al2O3–Mg multilayered nanocomposites by accumulative roll bonding process and study of its microstructure, tensile, and bending properties

Accumulative roll bonding is used for producing multilayered composites, with exciting mechanical properties, via the creation of bonding between dissimilar metallic layers. In this study for the first time, Al–Mg multilayered composites reinforced with nano-Al2O3 particles were produced by the accumulative roll bonding process at different temperatures. However, there was a problem regarding the adhesion of the nanoceramic particles with each other and with the sheet metals. To avoid these disadvantageous effects of the Al2O3 particle addition and to create better adhesion at interfaces, Al and different percentages of Al2O3 powders were ball milled and Al/Al2O3 composite powders were produced. Afterward, the composite powder was added between Al and Mg sheets and they were rolled to 50% reduction in thickness in each cycle. The process was continued up to four cycles at different temperatures. The microstructural evaluation and mechanical properties of aluminum/nanoalumina/magnesium composites showed that 300℃ is suitable temperature for accumulative roll bonding of Al and Mg sheets with nano-Al2O3 particles. Accumulative roll bonded composites with Al/5 wt% Al2O3 composite powder showed higher tensile strength while the maximum bending strength was related to the composites containing Al/10 wt% Al2O3. Fracture surfaces of the nanocomposites revealed a brittle fracture at higher cycles.