Performance Analysis of 3D Printing Functional Prepreg Filaments Based on Carbon Nanotube Fiber Reinforced Carbon Fiber Composites

This study prepared carbon nanotube fiber (CNTF) reinforced carbon fiber (CF) composites via melt impregnation, addressing the performance degradation caused by excessive carbon nanotube (CNT) content in conventional methods. It investigated the influence of CNTF content on composite properties and applied the material in FDM 3D printing. Results indicate that compared to CCF/PA6, CCF‐2CNTFs/PA6 exhibited enhanced thermal stability and crystallinity, with tensile strength and tensile modulus increasing by 52.2% and 103.4%, respectively, and electrical conductivity rising by 142.4%. In 3D‐printed specimens, thermal conductivity increased by 108.2%, demonstrating superior thermal management capabilities. Microscopic characterization reveals that CNTF reduced composite porosity, enhancing interlayer bonding in printed structures. This material offers novel insights for increasing CNT content, laying the foundation for future high‐performance fiber applications in high‐stress environments.