三种纳米碳材料吸波涂层设计及性能

Design and Microwave Absorbing Properties of Carbon Nano-Materials Single-Layer Microwave Absorbers

对纳米炭黑(UC)、特导纳米炭黑(L6)、碳纳米管(CNT)三种材料在8～18 GHz波段吸波涂层进行了优化设计及吸波性能分析。结果表明,三种材料的复介电常数随着纳米碳材料质量分数的增加,其实部和虚部均以不同的速度增大。利用理论计算的Cole-Cole图,结合实验测得的复介电常数,求解出这三种材料理想的介电常数,材料的质量分数和吸波涂层的匹配厚度。结果表明,CNT的吸波效果最好,当CNT质量分数为20%涂层、厚度为1.6 mm时,反射衰减率在11.2～15 GHz均优于-10 dB吸收峰最大值,达到29.6 dB。

In this paper,the microwave absorption properties of three different types of carbon nano-materials such as U carbon,carbon nanotube and carbon black have been studied at the frequency band of 8 to 18 GHz.The complex permittivity of carbon nano-materials/paraffin composite with different weight fractions were measured at the frequency band of 8 to 18 GHz.The results show that the real and imaginary of the complex permittivity of the composites were increased with filler weight and the increasing rates of the real and imaginary part with respect to the filler weight were all different.These different rates have great effect on the thickness in the designing the single-layer microwave absorbers.The match thickness of coating and the weight of filler were obtained by the Cole-Cole plot.When 20% mass fraction carbon nanotubes were used with coating thickness of 1.6 mm,the reflection loss is superior to-10 dB at 11.2 to 15 GHz and the maximum reflection loss can reach-29.6 dB.