摘要
The pyrolytic carbon （PyC） coatings were fabricated on A1203 fiber fabrics by the method of chemical vapor deposition （CVD）. The microstructures of A1203 fibers with and without PyC coatings were characterized by SEM and Raman spectroscopy. The influence of deposition time of PyC on the DC conductivity （ad） of A1203 filaments and complex permittivity of fabrics at X band （8.2-12.4 GHz） were investigated. The values of Crd and complex permittivity increase with increasing deposition time of PyC. The electron relaxation polarization and conductance loss were supposed to be contributed to the increase of ε＇ and ε＂, respectively. In addition, the reflection loss （RL） of fabrics was calculated. The results show that the microwave absorbing properties of Al2O3 fiber fabrics can be improved by PyC coatings. The best RL results are for 60 min-deposition sample, of which the minimum value is about -40.4 dB at about 9.5 GHz and the absorbing frequency band （AFB） is about 4 GHz.
采用化学气相沉积法在Al2O3纤维编织体上沉积热解碳涂层,利用SEM及激光拉曼光谱表征沉积与未沉积热解碳界面层的纤维编织体,并研究热解碳沉积时间对纤维电导率及编织体X波段介电吸波性能的影响。结果表明:纤维电导率及编织体复介电常数随着热解碳沉积时间的延长而增大。电子松弛极化引起复介电常数实部的增大,电导损耗引起虚部的增大。热解碳涂层可以改善Al2O3纤维编织体的吸波性能,对于沉积60min热解碳涂层的编织体,反射率在9.5GHz附近达到-40.4dB,吸波频带接近4GHz.
基金
Project (51072165) supported by the National Natural Science Foundation of China
Project (KP200901) supported by the Fund of the State Key Laboratory of Solidification Processing,China
