High-performance carbon/carbon composites with enhanced thermal conductivity via polyacrylonitrile fiber and pyrolytic carbon synergies

Abstract

The advancement of highly integrated electronic devices has driven the demand for composites with higher strength and thermal conductivity (TC). Polyacrylonitrile (PAN)-based carbon fibers (CFs) offer high availability, low cost, and excellent mechanical properties, but their thermal conductivity is relatively low. Developing carbon fiber composites with both high thermal conductivity and superior mechanical performance holds significant practical value. In this paper, the carbon/carbon (C/C) with a skeleton structure was prepared using braiding and molding, and the C/C was prepared by pressurized liquid-phase impregnation with high-temperature heat treatment. The results show that when the density of C/C is 1.41 g/cm³, the highest in-plane and through-plane TC can reach 205.87 W/mK and 57.33 W/mK, respectively, and the highest electrical conductivity can up to 882.1 S/cm. The flexural strength of C/C exceeds 100 MPa, and they also show certain friction resistance, with a coefficient of friction of 0.18 at the lowest. Infrared imaging and LED applications show that the prepared C/C have excellent thermal management performance. The above preparation process and the analysis of heat transfer provide some suggestions for the design of C/C thermally conductive composites.