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چکیده
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Multilayered aluminum composites have attracted increasing attention due to their potential to combine desirable properties of different alloys, making them suitable for lightweight and high-performance structural applications. The accumulative roll bonding (ARB) process is an effective technique for producing such composites with ultrafine microstructures. In the present investigation, dissimilar laminated composite of the AA1050 and AA6061 aluminum alloys was fabricated up to four cycles of the accumulative roll bonding process with intermediate annealing at 350 °C for 10 min. The effect of final annealing at temperatures of 200, 300, 400 and 500 °C for 15, 30 and 60 min on the microstructure and mechanical properties of the developed laminated composites were analyzed using optical microscopy and tensile testing. Results showed that with annealing at 200 °C, the hardness increases compared to the non-annealed sample, which could be due to the hardening by annealing phenomenon, which usually occurs in nanostructured materials, but at annealing temperatures of 300, 400 and 500 °C, the hardness decreases due to the occurrence of static recovery and recrystallization. It is also observed that the recovery and recrystallization delayed at AA6061 layers compared with AA1050 layers. Laminated composites developed through 3 and 4 cycles of ARB show higher tensile strength, due to lower grain size, and higher elongation, due to the low dislocation density, compared with the individual AA1050 and AA6061 sheets. These findings demonstrate that proper control of ARB cycles and annealing parameters can effectively tailor the microstructure and mechanical behavior of aluminum laminated composites.
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