Graphene nano-platelets reinforced aluminum composites with anisotropic compressive properties

Abstract Our recent work demonstrated that 5.0 vol% graphene nano-platelets (GNPs) may be introduced to aluminum alloys via powder metallurgy (PM) and multi-pass hot drawing. The produced composite rods had homogeneous GNPs distribution and high interfacial bonding strength and thus exhibited superior tensile strength compared to monolithic Al alloy. Moreover, aligned GNPs in various matrices can achieve stronger improvement in mechanical properties compared to composites with randomly distributed GNPs. Here, the GNP orientation dependent mechanical properties were demonstrated by compressive tests. The compressive yield strength (CYS) and ultimate compressive strength (UCS) of composite rods along drawn direction were increased 47% and 35% than those of Al, respectively. In addition, the composite rods showed higher CYS in drawn direction than that in radial direction. The anisotropic CYS may be related to texture and alignment of dispersed GNPs in composites created by multiple drawing.