模板法制备MoSi 2 /竹炭复合材料及吸波性能
摘要
Using the bamboo charcoal(BC) material as the template, the metallic chemical compound MoSi<sub>2</sub> as the absorption catalyst, the MoSi<sub>2</sub>/BC porous composite materials were fabricated by the embedded solid reaction sintering method. The components, microstructure and dielectric constant of the MoSi<sub>2</sub>/BC composite material were detected by XRD, SEM and vector network analyzer respectively. The results show that in the argon protective atmosphere(Ar), at the sintering temperature of 1450℃, the phase composition of MoSi<sub>2</sub>/BC composite material primarily consists of MoSi<sub>2</sub>, SiC and amorphous carbon. In the pores of the bamboo charcoal, the SiC whiskers(SiC<sub>W</sub>) are distributed in an irregular way with different size and length, furthermore to form an intersecting network except MoSi<sub>2</sub> particles. The existence of SiC<sub>W</sub> can significantly improve the wave absorption ability. At the range of 8.2-12.4GHz, after mixed with epoxy resin, the reflection losses of the composites of MoSi<sub>2</sub>/BC are gradually decreased with the increase of MoSi<sub>2</sub>/BC content. With the increase of sample thickness at the MoSi<sub>2</sub>/BC 50%(mass fraction) content, the minimum absorption peak of reflection loss is moving to the low frequency. The composites' lowest reflection loss is -13dB at 11.87GHz, and the reflection bandwidth value below -10dB is around 1.0GHz.This ind-icates that the MoSi<sub>2</sub>/BC composites possess perfect microwave absorbing performance.