SiC_NW-C_f/LAS复合材料的制备和电磁波吸收性能

SiC_NW were prepared with different molar ratio of silicon to carbon on carbon fiber cloth by thermal evaporation method using acetylene black as carbon source. SiC_NW-C_f/LAS(Li₂O-Al₂O₃-SiO₂) were prepared by using slurry-impregnation and vacuum sintering process with SiC_NW-C_f as intermediate interlayer. The results show that as the molar ratio of silicon to carbon decreasing, the diameter of SiC_NW decreases continuously, and the yield first increases and then decreases and reaches the highest when the molar ratio of silicon to carbon is 1: 3. The SiC_NW-C_f/LAS prepared with a molar ratio of silicon to carbon of 1: 1 has a minimum reflection loss of -40.9 dB (7 GHz, 3 mm) for electromagnetic wave. The SiC_NW-C_f/LAS prepared at a molar ratio of silicon to carbon of 1: 3 has a maximum effective bandwidth for absorbing electromagnetic wave of 4.61 GHz (Ku band, 1.5 mm). The excellent absorbing properties of SiC_NW-C_f/LAS composites can be attributed to their higher dielectric loss and scattering loss for electromagnetic wave and adjustment of LAS to material and space impedance matching.