In situ synthesis of copper-modified graphene-reinforced aluminum nanocomposites with balanced strength and ductility

In this work, a novel copper nanoparticles-modified graphene (Cu-NPs@GN)-reinforced Al matrix composites were fabricated. The Cu-NPs@GN hybrids were firstly synthesized by an NaCl template-assisted in situ CVD method and then incorporated into the Al matrix to fabricate Cu-NPs@GN/Al bulk composites by cold-press sintering and hot extrusion. With the merit of the unique characteristic of Cu-NPs@GN hybrid, the Cu-NPs@GN/Al composites exhibited homogeneously dispersed GNs and a strong GN–Al interfacial bonding. It was found that the in situ grown Cu-NPs@GN showed much better strengthening effect than that of the ex situ grown counterparts, which might be attributed to the pinning effect of Al₂Cu at the interface and thus promote the load transfer efficiency. Compared with pure Al, the composites with only 0.75 wt% Cu-NPs@GN exhibited a 68% increase in tensile strength (224 MPa) as well as had a total elongation of 17.5%.