PREPARATION AND MICROWAVE ATTENUATION PROPERTY IN THE X BAND OF SiC-C COMPOSITES

摘要

For developing an effective, low-cost method on preparation of microwave attenuation material, SiC-C composites with different additions of graphite grain were fabricated with solid phase sintering and liquid phase sintering, respectively. The microwave attenuation and the relative electrical properties of composites in the X band were measured. The results show that both methods are cost-effective and easily controllable processes and Solid phase sintering was more suitable to obtain SiC-C attenuation composites than the liquid phase sintering. The composite with 3 wt. % C prepared by solid phase sintering exhibited the best microwave attenuation, the biggest attenuation was -40.5 dB and most attenuations were above -30 dB in the whole X band. Furthermore, the microwave attenuation of composites depended strongly on the C additions; Match of interface of wave impedance and high wave consumption are both necessary for microwave attenuation materials.