Microstructure, properties and synergetic effect of graphene oxide-functionalized carbon nanotubes hybrid reinforced copper matrix composites prepared by DC electrodeposition

As the prospective carbon materials, graphene oxide (GO) and carbon nanotubes (CNTs) have attracted extensive attention in the fabrication of copper matrix composites (CMCs), but how their orientation and synergetic effect in Cu matrix affects the properties of composites has not been explored systematically. Herein, an efficient route to fabricate CMCs with GO-CNTs hybrid reinforcement had been reported, as well as the influence of different carbon reinforcement and different current densities on the texture orientation, microstructure and the comprehensive performance were investigated. From ultraviolet–visible results, it was found that one-dimensional CNTs bridge adjacent two-dimensional GO through π-π bonding to form an interconnected network structure. By adding GO-CNTs hybrid reinforcement to pure Cu sulfate, the preferred crystalline orientation of the GO-CNTs/Cu had been changed and a preferred orientation of (111) crystal plane was formed. Meanwhile, the EBSD results revealed that the GO-CNTs hybrid reinforcement had significant grain refinement effect and the average grain size of GO-CNTs/Cu composite reduced to 112 nm. According to TEM images, the lattice stripes between GO and CNTs indicate the formation of C–C covalent bonding. Owing to the synergistic effect and the C–C covalent bonding between GO and CNTs, the highest thermal conductivity reached to 527 W m−1 K−1, while, the highest hardness was up to 226.8 HV0.1, the friction coefficient reduced to 0.62and excellent corrosion resistance of the GO-CNTs/Cu composite were also achieved. This study suggested that the promising fabrication of high-oriented GO-CNTs/Cu composite may have the potential to obtain excellent performance.