Simultaneous enhancement of graphene dispersion and interfacial bonding in aluminum-graphene composites via in situ formation of Al2O3

Well dispersed graphene and good interfacial bonding are crucial for the synthesis of aluminum (Al)-based composites with high performance. To achieve this goal, graphene oxide (GO) was used to fabricate Al-RGO (reduced GO) composites via the in-situ formation of Al 2 O 3 . Detailed microstructure analyses revealed two forms of interface structures present in the as-extruded material, specifically RGO/γ-Al 2 O 3 /Al and RGO/amorphous-Al 2 O 3 /Al, which formed from interfacial reactions between GO and the Al metal. The as-generated Al 2 O 3 (γ/amorphous) phases substantially improved the interface bond between RGO and the Al matrix. Meanwhile, RGO nanosheets were uniformly dispersed within the Al matrix without evident structural degradation. As a result, the incorporated RGO notably improved the mechanical properties of the composite, resulting in a 216.2% increase in yield strength and a 65.2% increase in microhardness for the composite containing 0.5 wt% GO compared to the pure Al. These findings provide a viable route into the synthesis of Al-graphene composites with high performance.