Preparation and Microwave-Absorption Property of SiO_2-SiC-Based Composites

摘要

SiO_2-SiC composite particles were prepared using a sol-gel process. BaTiO_3 powders were synthesize through solid-state reaction. They were mixed as microwave absorbents with Fe_3O_4 powders to obtain the complex absorption. Epoxide resin (EP) was used as matrix and solidified with the mixtures. The techniques of DSC-TG, XRD were used to characterize the composite particles and the obtained compacts. A vector network analyzer was used to measure the reflectivity of the SiO_2-SiC-based composites. The effects of the aborbents' contents on the reflection of the microwave absorption materials were disscussed. It was found that SiO_2-SiC composites could be prepared using sol-gel process and BaTiO_3 powders could be synthesize through solid-state reaction. The results indicated that SiO_2-SiC composite is contribute to absorb microwave, where SiO_2-SiC: BaTiO_3: Fe_3O_4 = 6:2:2 (vol %), the frequency region in which the maximum reflectivity is more than -10 dB is 5.4-7.6 GHz.