Research progress in high thermal conductivity fibers

High thermal conductivity fibers have become increasingly crucial for efficient thermal management in rapidly advancing fields such as aerospace, high-speed vehicles, electronic chips, and artificial intelligence. The high thermal conductive fibers are indispensable for addressing the significant challenge of heat accumulation and limited heat dissipation capabilities in high-power chips and high-speed vehicles. Their unique properties, including high directional thermal conductivity, strength, lightweight nature, and a wide operating temperature range, render them an ideal material for rapid and directional heat dissipation in aerospace and electronic products. The historical development of carbon-based fibers, such as carbon fibers, carbon nanotube fibers, and graphene fibers, demonstrates remarkable performance in various fields. The evolution began with the development of polyacrylonitrile-based carbon fibers in the 1960s, followed by the emergence of pitch-based carbon fibers, which offered distinguishing strength, modulus, and chemical stability. These materials experienced significant advancements in production techniques, further boosting the thermal and mechanical properties of carbon nanotube fibers and graphene fibers. The superior properties of these materials are largely attributed to the sp2 hybridized carbon atoms and the sigma/π bonds. This review focuses on the preparation methods and thermal enhancement mechanisms of mesophase pitch-based carbon fibers, boron nitride fibers, carbon nanotube fibers, and graphene fibers. Detailed illustrations of the preparation processes, structural features, and thermal properties of these fibers are provided. Despite substantial progress, challenges remain in reaching the theoretical thermal conductivity values. The immense potential applications of high thermal conductivity fibers in advanced fields such as aerospace underscore the importance of not only improving fiber performance but also ensuring scalable production to meet industrial demands. This review comprehensively covers the advancements in high thermal conductivity fiber performance, preparation methods, and the mechanisms behind their thermal conductivity. Additionally, it discusses various testing methods for thermal conductivity to evaluate the current application status of these fibers across different fields. Furthermore, we also provide the perspectives for future research directions. Although continuous advancements in fiber assembly technologies and enhancement mechanisms have led to rapid improvements in fiber thermal performance, there remains a gap between current achievements and theoretical values. With the ongoing development in cutting-edge fields like aerospace, the demand for high thermal conductivity fibers is still for from expected, driving further innovations and improvements in both performance and production scalability. In summary, high thermal conductivity fibers are at the forefront of materials research due to their essential role in efficient thermal management. Their development history, preparation methods, and applications are critical for future technological advancements, particularly in high-demand areas such as aerospace and electronics. The ongoing research and development efforts aim to bridge the gap between current capabilities and theoretical potential, paving the way for more efficient and scalable solutions in thermal management. The future of high thermal conductivity fibers holds promising potential for broader industrial applications, making them a vital component in the advancement of modern technology.