Synergistic effect of woven copper wires with graphene foams for high thermal conductivity of carbon fiber/epoxy composites

Enhancing the thermal conductivity of carbon fiber laminated composites (CFRP) in out-of-plane directions without sacrificing mechanical properties is still challenging for the fabrication of high-performance composites with structural and functional integration. In this work, a novel hybrid sandwich composite was fabricated by weaving copper wires through carbon fiber (CF) fabrics, laminating graphene foams (GrFs) onto surfaces, and infiltrating with epoxy via the vacuum-assisted resin transfer molding technique. High-efficiency heat transfer pathways were constructed to greatly increase the out-of-plane thermal conductivity of composites with maintaining CF continuity. Microstructure, electrical property, and thermal conduction of composites were experimentally measured and theoretically simulated. The hybrid sandwich composites exhibited improved electrical and thermal conductivity due to the continuous conductive pathways, and their out-of-plane thermal conductivity was up to 1.097 W/m·K, increasing by 104% in comparison with that of CFRP. Such remarkable thermal enhancement is mainly attributed to the high intrinsic conductivity of the copper wire and GrF, continuous heat transfer pathways, and synergistic effect of copper wire with GrF for rapid heat transfer and diffusion. The hybrid sandwich composites show great potential to be utilized as high-performance materials with structural and functional integration in the fields of aerospace and transportation.