摘要
通过对圆形和三叶形截面SiC纤维进行热处理改性，发现改变热处理条件，可有效调整纤维介电性能，利用不同截面纤维处理前后介电性能和阻抗的差异，根据阻抗匹配原理，制备了几种不同SiC纤维组合层板吸波材料。结果表明，有两种组合的层板复合材料在10～18GHz频段反射率低于-10dB，8～10GHz频段内反射率低于-8dB，具有良好的吸波性能。层板中透波层（改性圆形SiC纤维）的加入对提高其吸波性能效果明显，改性三叶形纤维的加入对改善低频段吸波性能作用明显。
The dielectric properties of SiC fibers with circular/trilobal cross-section can be effectively tuned by changing their thermal treatment conditions. On the basis of the differences in dielectric properties and impedances of the fibers caused by heat treatment, muhilayer structural microwave-absorbing materials （SMAMs） reinforced by various SiC fibers of different cross sections were designed according to the impedance matching principle. It was found that two types of the multi-layer SMAMs exhibited excellent microwave absorbing properties. The reflectivity was less than -10 dB and -8 dB in 10-18 GHz and 8- 10 GHz bandwidth, respectively. By adding the wave-transparent layer （the thermal treated SiC fibers of circular cross-section）, the microwave-absorbing properties of the corresponding composites were highly improved. Meanwhile, the addition of SiC fibers of trilobal cross-section to the composites could hugely enhance their absorbance to low frequency waves.
基金
国家高技术研究发展计划(863计划)资助项目(2002AA305101)
关键词
SIC纤维
热处理
三叶形截面
吸波性能
SiC fibers
thermal treating
trilobal cross-section
absorbing property
