Inhomogeneous copper matrix composites reinforced by RGO/Cu composite foams with high electrical conductivity, tensile strength and fracture elongation

A three-dimensional (3-D) skeleton-reinforced copper composite was designed to overcome the paradox between strength and ductility or conductivity. Open cell copper matrix foams with uniformly embedded reduced graphene oxide (RGO) were prepared via electrodeposition. The foam pores were filled with pure copper phase via spark plasma sintering (SPS). Cu2O nanoparticles were formed at the RGO-Cu interface, resulting in improved interfacial bonding. Three-dimensional skeleton-reinforced composites showing a combination of high electrical conductivity (93.24% IACS), tensile strength (343 MPa), and fracture elongation (39.4%) were fabricated with low levels of RGO (0.024 wt%). The possible strengthening mechanism of the skeleton-reinforced composites is discussed basing on the test results.