碳纳米管/聚合物复合吸波材料的研究进展

简要介绍了吸波材料研究的重要性,综述了碳纳米管/聚合物吸波材料的研究现状,主要包括碳纳米管/环氧树脂(ER)复合材料、碳纳米管/聚苯胺(PANI)复合材料以及碳纳米管/聚氯乙烯(PVC)复合材料的制备方法和吸波性能;并展望了碳纳米管/聚合物复合材料在航天工业领域的发展方向.     

磁性吸附碳纳米管复合材料在吸波材料中的应用及展望

总结了近年来磁性金属或合金/碳纳米管复合材料在雷达波吸波材料中的应用及发展现状,并介绍了碳纳米管的磁性吸附对吸波性能的影响,最后对碳纳米管在吸波材料中的应用作出展望。     

纳米吸波材料的研究现状与发展趋势

评述了纳米吸波材料的特性及吸波原理,介绍了纳米铁氧体吸波材料、纳米金属吸波材料、纳米陶瓷吸波材料、纳米导电高分子吸波复合材料、碳纳米管吸波材料、纳米复合吸波材料研究现状及发展情况,指出了纳米复合吸波材料是未来纳米吸波材料的研究重点。     

树脂基复合吸波材料在航空、航天中的应用

 本文介绍了目前应用在吸波中的几种新型的树脂基吸波复合材料,如碳/热塑性树脂基复合材料、纤维增强 树脂基复合材料、树脂基纳米复合材料。文中还结合材料的研究,阐述了表征材料吸波性能的方法,如反射系数和 电磁参数。最后讨论了树脂基吸波复合材料在飞机、战术导弹上的应用。     

纳米吸波剂改性水泥基材料研究进展

水泥基吸波材料可以有效缓解电磁波辐射对人们日常生活的影响。传统吸波剂所制备的水泥基吸波材料因其有效带宽窄、吸波效率低和体积厚重等缺点，限制了其在工程中的应用。与之相比，纳米吸波剂具有量子尺寸效应、宏观量子隧道效应和界面效应等特点，因此纳米吸波剂改性水泥基材料为电磁辐射防护提供了一个新途径。根据纳米吸波剂种类的不同，从碳纳米管水泥基吸波材料、石墨烯水泥基吸波材料和磁性纳米颗粒水泥基吸波材料3个方面总结了国内外相关研究成果，并对未来该领域的发展进行了展望。     

结构型碳纤维吸波复合材料的研究及应用

结构型碳纤维吸波复合材料结合了复合材料轻质高强的结构优势和吸波特性,是雷达隐身材料的重要发展方向。本文主要从异型截面碳纤维、手性碳纤维和碳纳米管等新型吸波碳纤维增强体以及夹芯结构、点阵结构形式等方面总结了结构型碳纤维吸波复合材料国内外的最新研究和应用进展,并指出了未来发展方向。     

碳纳米管基吸波复合材料的研究进展

主要介绍了碳纳米管吸波材料及碳纳米管,磁损耗物质、碳纳米管／高分子聚合物、碳纳米管／磁损耗物质／高分子聚合物复合材料的研究现状,并对其进行展望。     

吸波材料研究进展

简述了吸波材料的吸波物理机理、吸波特性、吸波材料分类以及吸波材料的应用领域。并结合实际指出多晶金属纤维、SiC基陶瓷和C／C复合材料是目前性能最佳、应用前景最好的电磁波吸收材料。     

纤维增强树脂基吸波复合材料的研究进展

简述了吸波材料的电磁屏蔽机制、吸波剂的分类和损耗机制以及微波波段的划分与应用,并从材料的选择、结构的设计以及获得的吸波效果等方面对目前纤维增强树脂基吸波复合材料的研究进行了对比总结,重点阐述了单层结构、多层结构、多层夹心结构以及频率选择表面的主要特点和研究现状。最后提出了纤维增强树脂基吸波复合材料目前存在的问题,并对今后的发展进行了展望。     

结构型吸波复合材料的研究进展

结构型吸波复合材料具有吸波性能好、质量轻、可承载等优点,已成为当代吸波材料的主要发展方向,对隐身材料的设计和制造有着重要意义。本文从纤维增强体的截面形状和制备工艺、纤维的铺排结构和夹层复合结构、吸波剂改性等影响吸波复合材料吸波性能的主要因素出发,系统地总结了结构型吸波复合材料的最新研究热点和成果,并指出吸波复合材料的未来发展方向。     

Enhanced electromagnetic wave absorbing properties of Si-O-C ceramics with in-situ formed 1D nanostructures

The Si-O-C ceramics were prepared by polymer-derived ceramic method using polysiloxane/FeCl₃ as precursor with the FeCl₃ content of 1.0 wt%. The microstructure, dielectric properties, and electromagnetic wave (EMW) absorbing properties in X band of the Si-O-C ceramic were investigated. It was found that the pyrolysis temperature has a great influence on the amount of in-situ formed CNTs and the transformation from CNTs to 1D SiC nanostructures. With the temperature rising from 1000 to 1500°C, the SiC formed with various morphologies including SiC microspheres, needle-like SiC, and SiC nanowires which were transformed from CNTs. The EMW absorbing properties were dramatically improved when the pyrolysis temperature raised to 1500°C; the minimum reflection loss (RL) was −58.37 dB of sample with a thickness of 2.95 mm at 10.11 GHz, and the absorbing band (RL ≤−20 dB) of sample at a thickness of 3.0 mm covers 3.8 GHz (8.2-12.0 GHz), which means more than 99% of the EMW were absorbed. The enhancement of EMW absorbing properties of bulk Si-O-C ceramics was attributed to the interfacial polarization induced by in-situ heterogeneous nanostructures with complex interfaces.     

Electromagnetic and electromagnetic wave‐absorbing properties of the SrTiO3–Epoxy composite

The effects of SrTiO₃ content on the electromagnetic properties and electromagnetic wave‐absorbing characteristics of SrTiO₃–epoxy composites were investigated. Also, the frequency dispersion behavior of the complex permittivity of composites was demonstrated. The complex permittivity and permeability were measured using a network analyzer in the frequency range of 130 MHz to 10 GHz. As the SrTiO₃ content increased, it was found that the complex permittivity and permeability of the composites increased and the resonance frequency moved toward low frequency range. The logarithmic model coincided with the effective permittivity of composite as a function of SrTiO₃ content comparatively well. The resonance frequency of composites was found to show good agreement with the theoretical values calculated by the equation proposed in this article. The electromagnetic wave‐absorbing behavior showed that the center frequency of attenuation curve was shifted to a lower frequency band with increasing the amount of SrTiO₃ and the thickness of composite. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 72: 75–83, 1999     

Recent advances in carbon nanotubes-based microwave absorbing composites

With the blossom of information industry, electromagnetic wave technology shows increasingly potential in many fields. Nevertheless, the trouble caused by electromagnetic waves has also drawn extensive attention. For instance, electromagnetic pollution can threaten information safety in vital fields and the normal function of delicate electronic devices. Consequently, electromagnetic pollution and interference become an urgent issue that needs to be addressed. Carbon nanotubes (CNTs) have become a potential candidate to deal with these problems due to many advantages, such as high dielectric loss, remarkable thermodynamic stability, and low density. With the appearance of climbing demands, however, the carbon nanotubes combining various composites have shown greater prospects than the single CNTs in microwave absorbing materials. In this short review, recent advances in CNTs-based microwave absorbing materials were comprehensively discussed. Typically, we introduced the electromagnetic wave absorption mechanism of CNTs-based microwave absorbing materials and generalized the development of CNTs-based microwave absorbers, including CNTs-based magnetic metal composites, CNTs-based ferrite composites, and CNTs-based polymer composites. Ultimately, the growing trend and bottleneck of CNTs-based composites for microwave absorption were analyzed to provide some available ideas to more scientific workers.     

电磁波吸收层的设计与吸波材料的应用

介绍雷达吸波材料与吸波结构，以及电磁波吸收层的电性能设计方法，并探讨了单层和双层吸收层的设计。     

Microwave Absorbing Performances of Silica Matrix Composites Reinforced by Carbon Nanotubes and Carbon Fiber

Multilayered composites consisting of silica, carbon nanotubes (CNTs), and continuous carbon fibers (C_f) were prepared by hot‐pressing technique. Microstructures of different layer presented few pores of the composites. The thermal stability of the composites was analyzed by TG/DTA measurement. After being heat treated at 400°C for 10 h, the composites retained the equivalent shielding property compared to room temperature, and the impedance matching property at material/wave interface was improved slightly. The multilayer CNTs/C_f/silica composites have not only the excellent absorbing properties but also the outstanding thermal stability, and it can be a promising candidate for high‐temperature electromagnetic interference shielding applications.     

Millimeter wave absorbing property of flexible graphene/acrylonitrile-butadiene rubber composite in 5G frequency band

The coming fifth generation mobile communication technology (5G) puts forward enormous requirements on millimeter wave (MMW) absorbing materials above 24 GHz. In the present work, elastic absorbing composites were fabricated with reduced graphene oxide (RGO) of different reduction time and nitrile rubber (NBR). A series of characterization methods were used to study the reduction degree and the structure of composites, the electromagnetic parameters of composites in 26.5–40 GHz were also measured and used to conduct an analytical computation of reflection loss (RL). It was found that, 3h-RGO/NBR presented the minimum RL of ?45 dB at 35.4 GHz while 7h-RGO/NBR exhibited the widest effective bandwidth (<-10 dB) about 6.5 GHz. In addition, the mechanical properties of composites were also improved by RGO. Therefore, the obtained RGO/NBR composites displayed promising prospect as elastic MMW absorbing materials for 5G applications.     

活化碳纳米管的孔结构及微波吸收性能的研究

以KOH为活化剂对碳纳米管进行活化处理，将碳纳米管的比表面积从24．5m^2/g提高到360．1m^2／g，孔容从0．051cc／g提高到0．572cc/g。对碳纳米管的微波吸收性能进行测试，研究结果发现，未活化碳纳米管在9．91～14．16GHz范围内对电磁波的反射率低于-5dB，最大衰减峰值为8．57dB；活化碳纳米管在5．37～18GHz范围内对电磁波的反射率低于一5dB，在6．48～10．88GHz范围内对电磁波的反射率低于一10dB，最大的衰减峰值达到22．58dB。通过比较得出，活化能够有效地提高碳纳米管的微波吸收性能。产生的原因是由于活化碳纳米管具有大的比表面积和丰富的孔结构，电磁波在这些孔结构中不断的被反射、漫射而逐渐衰减。     

聚氨酯泡沫夹层复合材料的制备及其吸波性能研究

根据电磁波阻抗匹配原理,制备了聚氨酯泡沫夹层结构复合吸波材料,研究了不同结构组成对材料吸波性能的影响。实验结果表明:当匹配层中加入质量分数15%的二氧化锰,聚氨酯泡沫夹芯层中加入质量分数5%的二氧化锰和10%的石墨和反射层中加入质量分数35%的石墨时,测试频段为8～18 GHz,聚氨酯泡沫夹层结构复合材料的最大吸收峰为12.9 GHz(R=-35.7 dB),R-10 dB的频宽为1.5 GHz。     

炭纤维吸波复合材料结构设计的研究进展

总结了炭纤维吸波性能的电磁改性方法,重点介绍了结构设计对炭纤维吸波复合材料吸波性能的影响,包括短切炭纤维、炭纤维排布结构、炭纤维电路模拟结构以及含炭纤维的混杂纤维排布对炭纤维复合材料吸波性能的影响.提出了炭纤维吸波复合材料今后的研究方向.     

吸波材料的微波损耗机理及结构设计

就吸波材料与电磁波的相互作用及其损耗机理进行了阐述。通过对吸波材料与电磁波相互作用的研究和不同类型吸波材料微波损耗机理的详细探讨，对研制高宽频、质轻、红外微波隐身兼容复合型吸波材料进行了展望，并提出了材料结构设计的思路。