Mechanical and electrical properties of copper-graphene nanocomposite fabricated by high pressure torsion

Graphene reinforced Cu matrix composite was fabricated by consolidating mechanically mixed powder blend to 98% theoretical density by High Pressure Torsion (HPT). Microstructural characterization by scanning electron microscopy (SEM) elicits even distribution of the reinforcement phase into the matrix. X-ray diffraction (XRD) and transmission electron microscopy (TEM) confirms nanocrystalline microstructure and strong interfacial bonding between Cu and graphene. Addition of 10 wt % graphene yields maximum hardness (similar to 2.67 GPa) and Young's modulus (similar to 102.03 GPa). The increment in strength was attributed to the microstructural refinement and dislocation pinning at the strong matrix-reinforcement interface. The electrical conductivity of the Cu- 10 wt% graphene composite was found to be similar to 87% IACS. Results indicated that HPT consolidation is an efficient mean for synthesizing Cu-graphene composite with improved strength (similar to 2 times higher hardness than pure Cu processed under similar condition) with negotiable conductivity. (C) 2018 Published by Elsevier B.V.