ABSTRACT The rapid development continues in areas such as 5G communications, high‐power electronics, and aerospace technology. This progress is creating an increasingly urgent demand for efficient thermal management materials. The construction of three‐dimensional carbon fiber networks serves as an effective method for producing high thermal conductivity composites. In this article, an innovative carbon fiber/phenolic three‐dimensional network skeleton was fabricated using ultrasonic dispersion, vacuum filtration, and hot‐press molding. Subsequently, carbon fiber/phenolic/epoxy (CF/PF/Epoxy) composite was successfully fabricated. It features a three‐dimensional continuous thermal conduction network, formed via vacuum resin infusion and hot‐press molding. The thermal conductivity of the composites was systematically investigated as a function of carbon fiber content. The results indicate that the in‐plane thermal conductivity of the composite reaches 56.19 W/(mK) (22.52 vol% CF), approximately 267.57 times that of epoxy. Microstructural analysis shows that phenolic resin enables carbon fibers to form a low‐density three‐dimensional network, which can efficiently transfer heat. Moreover, finite element simulations of the composites were performed using COMSOL software. The transient heat conduction equation for solids was derived by substituting Fourier's law into the energy conservation equation. Simulations demonstrate that CF/PF/Epoxy composites exhibit superior thermal conductivity. This confirms their excellent thermal management performance. In infrared thermal imaging and LED heat dissipation applications, these composites exhibit efficient heat transfer and uniform temperature distribution. This article provides a new approach for the controllable fabrication of high thermal conductivity composites with strong potential for engineering applications.
Wang et al. (Thu,) studied this question.