Abstract: The metal-salt impregnation and heat treatment process were used to load magnetic particles on the surface of carbon fiber, and the composites with excellent microwave absorbing properties were prepared with PU. As prepared materials were characterized and analyzed by XRD, SEM, EDS, thermodynamic analysis and segmental support-based adsorption method. The results showed that a large number of soft magnetic particles containing Fe, Co, Ni and other metallic elements are distributed on the surface of the prepared carbon fibers, and the magnetic particles are uniformly distributed along the carbon fibers in the axial direction. With the change of CF/Magnetic-particle content, performance of wave absorption is different. When the amount of addition is 12 g, the absorption property of the electromagnetic wave is the best, the absorption band of the electromagnetic wave loss <－10 dB were up to 7.6 GHz, and the maximum wave loss of －36.37 dB appears at 12.7 GHz; the microwave absorbing property of carbon fiber based magnetic absorbing composites could be controlled by CF/Magnetic-particle addition.

Key words: carbon fiber; magnetic particle; composite material; microwave absorbing property