Fabrication and Characterization of Graphene-Copper Composite Wires Using Chemical Vapor Deposition and Roller Drawing Techniques

Abstract Copper's high electrical and thermal conductivity makes it appealing for use in various industrial products. However, challenges related to its weight and performance in extreme environments limit copper's usage in aerospace applications. Previous research has demonstrated that incorporating multilayer graphene (MLG) on a copper substrate via chemical vapor deposition (CVD) improves the performance of this conductor in high-temperature applications without incurring a weight penalty. Incorporating a high percentage of large-area graphene, needed for better performance, is difficult while fabricating wires. This work shows a method for making high-quality graphene–copper composite wires from 25 µm and 50 µm copper foils, consolidated into a wire via repeated annealing and roller drawing reductions. A copper foil wire without graphene is compared to the composite to highlight graphene's benefits. This research correlates the composite's resulting material properties to the microstructure and creation process. The final results suggest that graphene content aids in consolidation, removing one of the primary defects in manufacturing wires from foils. Reducing porosity through improved consolidation prevents early fracture under tensile loading. In addition, the specific conductivity at room temperature for bilayer graphene (BLG), few-layer graphene, and MLG samples was comparable to that of bare copper wire. Graphene content also improves the resulting high-temperature electrical properties by protecting the wire from further oxidation. Based on the data presented in this article, recommendations are provided for further reducing void defects and enhancing the quality and performance of copper–graphene composite wires.