Synergistic effect of RGO loaded Al2O3 on microstructure and mechanical properties of 6061 aluminium alloy

Al6061 alloy matrix composites reinforced with nano-reduced graphene oxide loaded Al 2 O 3 (Al 2 O 3 /RGO) were successfully fabricated using high energy ball milling and hot extrusion techniques, with varying mass fractions. The microstructures of these Al 2 O 3 /RGO/Al6061 aluminium matrix composites (Al MMCs) were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM) attached with energy-dispersive X-ray spectroscopy (EDS), and transmission electron microscope (TEM). The tensile properties and Vickers hardness of the alloy were tested. The results show that Al 2 O 3 /RGO were uniformly distributed in the Al6061 matrix and tightly bonded to the matrix. Al 2 O 3 encapsulation on RGO surface eliminates Al 4 C 3 brittle phase in matrix, indicating that there was no reaction between the reinforcement and the matrix Al6061. The tensile strength and vickers hardness of Al MMCs increased after Al 2 O 3 /RGO were added. Tensile tests revealed that the yield strength and tensile strength of Al MMCs with a 0.1 wt.% reinforcement were 49% and 43% higher, respectively, compared to pure Al6061 prepared under the same process. And the alloys showed the best strength and considerable plastic deformation capability for that of 0.1 wt.% Al 2 O 3 /RGO.