螺旋形碳纤维结构吸波材料的制备及性能研究

用基板法以乙炔为碳源，镍板为催化剂，PCI，为助催化剂，通过化学气相沉积制备了螺旋形碳纤维手性吸收剂，并研究了其在2～18GHz的微波电磁特性：具有较高的介电损耗，电磁参数随频率的增大有减小的趋势，有利于实现宽频吸波。以螺旋形碳纤维作为吸收剂制备了Nomex蜂窝夹芯结构吸波材料，复合材料的厚度为9．5mm时，在3．76～18GHz反射率R小于-10dB，反射率小于-10dB的频宽为14．24GHz；最大吸收峰在10．4GHz，反射率R为-21．62dB。探讨了螺旋形碳纤维的吸波机理，螺旋形碳纤维是一种非常有发展前景的手性吸收剂和吸波材料。

Preparation and Microwave Absorbing Property of Nomex Honeycomb Sandwich Composites Filled with Coiled Carbon Fibers

The coiled carbon fiber chiral radar absorbers were prepared by Ni-catalyzed pyrolysis of acetylene containing a small amount of PCl. In order to investigate the microwave absorbing property and mechanism of the coiled carbon fiber chiral radar absorbers, the microwave electromagnetic characteristics of the coiled carbon fibers at the frequency range of 2-18 GHz were studied. The dissipation factors of the coiled carbon fibers were high and the real part （ε＇ and imaginary part （ε″） of its complex permittivity decrease with the frequency increasing in this frequency range. The reflection loss of the Nomex honeycomb sandwich composites filled with the coiled carbon fibers with a thickness of 9.5 mm is below -10 dB （90% absorption） in the range of 3.76-18 GHz, and the minimum value is -21.62 dB at 10.4 GHz. The bandwidth corresponding to the reflection loss below-10 dB is 14.24 GHz. The coiled carbon fibers are promising chiral absorbers in the application of radar absorbing materials.