摘要
碳纳米管(CNTs)因其高的电导率及介电损耗、可调谐的介电常数、低密度等优点在微波吸收材料领域受到广泛关注,但轻质高效CNTs基微波吸收体的简单设计与构筑仍然是一个挑战。一个微波吸收体的性能取决于其相对复磁导率和复介电常数,而填充量被广泛认为是调控电磁参数的一个简单有效的手段。直接以商用多壁碳纳米管(MWCNTs)作为吸收剂,通过简单调节其填充量以实现轻质高效微波吸收。当填充量仅为3.0 wt%时,因阻抗匹配与电磁衰减能力的更好平衡,获得了优异的综合吸波性能。最小反射损耗在2.5 mm厚度下达到–58.6 dB,最大有效吸收带宽在2.6 mm时为6.8 GHz,可覆盖整个Ku波段。此外,雷达散射截面(RCS)模拟仿真结果显示,其最大RCS降低值可达–38.94 dB·m^(2),展现出优异的雷达隐身性能,使该材料在民用和军事领域都具有良好的应用前景。
[Objective]The transmission of information using wireless technology has simplified people’s everyday lives;however,it has resulted in electromagnetic(EM)pollution,which endangers human health and equipment operation.Furthermore,the continuous progress in radar detection technology requires lightweight microwave absorbing materials coated on the surfaces of modern weapons and military equipment,especially aircraft;the objective is to reduce the enemy defense penetration and improve the battlefield survivability of military systems.[Methods]Microwave absorbing materials(MAMs)are highly important in protecting human health and ensuring the normal operation of electronic equipment,as well as improving the EM stealth capability of weapons and military equipment.MAMs absorb or attenuate the incident EM waves by converting their EM energy into thermal energy.Therefore,the development of MAMs that can cope with complex EM environments and exhibit broad bandwidth,light weight,small thickness,and strong absorption capability has become the research focus in related fields.In recent years,carbonaceous materials,such as carbon nanotubes(CNTs),carbon nanofibers,reduced graphene oxides,hollow carbon spheres,porous carbon,and onion-like carbon,have been extensively used as dielectric lossy fillers in MAMs because of their low density,good electrical conductivity,high dielectric loss,as well as excellent thermal stability and corrosion resistance.Notably,CNTs with a one-dimensional hollow nanostructure and tunable permittivity have attracted significant attention in the field of EM functional materials.Despite the recent progress in the development of CNT-based MAMs,designing and manufacturing lightweight and highly efficient CNT-based microwave absorbers remains a challenge.The performance of a microwave absorber mainly depends on its relative complex permittivity and complex permeability.Loading a microwave absorber with dielectric fillers has been widely regarded as a simple and effective technique to control its EM properties.Herein,commercial multiwalled carbon nanotubes(MWCNTs)are directly employed as fillers to develop lightweight and highly efficient microwave absorbers by simply adjusting their filling content.[Results]Using an MWCNT filling ratio of only 3 wt%in the paraffin matrix,an excellent absorption performance can be achieved;this is attributed to the improved balance between impedance matching and EM attenuation.For example,an absorber with a 2.5-mm thickness achieves a minimum return loss(RL)of−58.6 dB at 14.3 GHz,and an absorber with a 2.6 mm thickness achieves a maximum effective absorption bandwidth of 6.8 GHz with RL<−10 dB,thus covering the entire Ku band.This absorption performance is significantly better than that achieved in many previously reported carbon-based microwave absorbers with a much higher filling ratio.The simulation results of a radar cross-section(RCS)showed that an absorber with a 3 wt%MWCNT filling ratio achieves a maximum RCS reduction of−38.94 dB·m^(2) and sufficient radar stealth capability,effectively decreasing the possibility of target detection by a radar.[Conclusions]Overall,commercial MWCNTs with excellent microwave absorption and radar stealth performance could be used in the field of EM functional materials,covering a wide range of applications,from EM interference shielding for civilian electronics to radar stealth for advanced military equipment and systems.
作者
牛旭歌
吴粉
刘浩然
范雨晴
向军
NIU Xuge;WU Fen;LIU Haoran;FAN Yuqing;XIANG Jun(School of Science,Jiangsu University of Science and Technology,Zhenjiang 212100,China)
出处
《实验技术与管理》
北大核心
2025年第9期120-127,共8页
Experimental Technology and Management
基金
江苏省研究生科研创新计划项目(KYCX24_4101)
国家级大学生创新训练计划项目(202410289036Z)。
关键词
碳纳米管
介电损耗
阻抗匹配
微波吸收性能
轻质
carbon nanotubes
dielectric loss
impedance matching
microwave absorption performance
lightweight
作者简介
牛旭歌(2000-),女,河北保定,硕士研究生,主要从事微波吸收材料研究,976294993@qq.com;通信作者:向军(1974-),男,四川广安,博士,教授,主要从事微波吸收材料和电化学储能材料研究,jxiang@just.edu.cn。
