Effect of accumulative roll bonding on structural and mechanical properties of aluminum- reduced graphene oxide nanocomposite

Present study employed a combined approach of mechanical alloying and MLM to improve the dispersion of graphene within the aluminium matrix, followed by the application of the ARB process. This research incorporated copper nanoparticles and stearic acid during mechanical alloying, which significantly improved the dispersion and prevented the aggregation of graphene layers. Characterization by XRD, FTIR, and FESEM confirmed the homogeneous distribution of both graphene and copper nanoparticles, with no visible agglomeration. Mechanical alloying was conducted using a ball-to-powder weight ratio of 10:1, a combination of 5 mm and 10 mm balls, a rotation speed of 300 rpm, and 2 wt% stearic acid for 10 h. The ARB process was performed at a rolling speed of 12 rpm. XRD analysis confirmed the formation of the Al₂Cu intermetallic phase within the nanocomposite. Results of mechanical analysis showed that mechanical properties enhanced by adding reduced graphene oxide (RGO). , In the presence of 0.1 wt% RGO, a significant improvement in the microhardness, yield strength and ultimate strength of the AA2024/0.1%Y nanocomposite was obtained compared to the as-rolled matrix alloy, which is equal to 18.5% (from 79 to HV93.63), 60% (from 78 to 125 MPa) and 24.5% (from 125 to 155 MPa), respectively. The results of the subsequent heat treatment also showed an increasing in hardness, yield strength and ultimate tensile strength of approximately 20%, 17% and 10.5%, respectively.