非晶碳纳米管/石墨烯/钡铁氧体纳米杂化结构复合材料制备与吸波性能

Graphene and carbon nanotube have been become the hot research topic in the field of new carbon materials due to their excellent properties and wide applications. The investigations of nano-stealth materials are important frontiers and the hot-topic issues in the defense science and technology. It has mportant value for the scientific research and practical utilization to improve the narrower bandwidth and lower electromagnetic wave absorptivity of stealth material. In this project, a novel nano-stealth material based on the hybrid nanostructure of graphene, amorphous carbon nanotube (ACNT) and barium ferrite having large bandwidth and high absorptivity will be proposed and investigated. ACNT/graphene/barium ferrite/resin composites using graphene, modification ACNTs and barium ferrite as electromagnetic wave absorber are synthesized by mechanical rolling technology and the nanocomposite system of ACNT/graphene/barium ferrite hybrid nanostructure modified resin was established. The electromagnetic wave absorbing properties, micro-structure and mechanical behavior of the hybrid nanostructure composites are characterized and analyzed. The effects of modification graphene/ACNT/barium ferrite hybrid nanostructure on the electromagnetic wave absorbing performance of composites are also studied systematically. The experiments on how to improve the electromagnetic wave absorbing performances, as well as affect the factors of wave absorbing properties, mechanism and influence rules, will be carried out deeply. Based on quantum mechanics and classic electromagnetic theory, the mechanism of electromagnetic wave absorbing and influence rules of ACNT/3D graphene/barium ferrite/resin nanocomposites will be discussed. It is believed that this nanocomposite has a favorable ability of electromagnetic wave absorption in the bandwidth ranges of 2-18GHz with absorber thicknesses of 0.5-2mm. It greatly reduce the radar cross section(RCS) and increase the absorptivity of electromagnetic wave. The absorptivity and bandwidth of electromagnetic wave is expected to reach 97% (-15dB) and 8 GHz or even higher respectively.

石墨烯和碳纳米管由于具有优异的性能和广泛应用已成为新型碳材料领域的研究热点，而纳米隐身材料研究是国防科技中重大前沿和热点问题，提高隐身材料频率带宽和电磁波吸收率具有重要的科学研究意义和实用价值。本项目研究基于石墨烯和非晶碳纳米管与钡铁氧体复合杂化结构的新型纳米隐身吸波剂可大幅拓宽频率带宽和提高吸收率。以非晶碳纳米管/三维石墨烯/钡铁氧体纳米杂化结构作为吸波剂，建立吸波剂改性树脂基纳米复合体系，采用机械压延技术制取吸波复合材料。通过对复合材料进行微观组织结构和吸波性能的表征测试分析，揭示纳米杂化结构吸波剂用来提高吸波性能的影响规律和作用机制；基于量子理论和经典电磁理论提出其吸波机理。预期厚度在0.5～2mm，频宽在2～18GHz范围内新型纳米杂化结构吸波剂具有良好的电磁波吸收能力，能够大幅降低雷达散射截面(RCS)，力争对电磁波的吸收率达到97%（-15dB）的带宽在8GHz及以上。

纳米隐身材料研究是国防科技中重大前沿和热点问题，拓宽隐身材料较窄的频率带宽和提高其较低的电磁波吸收率具有重大的科学研究和实用价值。本项目完成了基于非晶碳纳米管/石墨烯/钡铁氧体纳米杂化结构可大幅拓宽频率带宽和提高吸收率。以非晶碳纳米管/石墨烯/钡铁氧体纳米杂化结构作为吸波剂，建立了非晶碳纳米管/石墨烯/钡铁氧体纳米杂化结构改性聚甲基丙烯酸甲酯（PMMA）纳米复合体系，采用机械压延技术制取了非晶碳纳米管/石墨烯/钡铁氧体树脂基多层吸波复合材料；揭示了纳米杂化结构对复合材料吸波性能的影响；提出了基于纳米杂化结构多层复合材料的吸波机理，并对吸波性能进行理论计算。.以非晶碳纳米管/石墨烯/钡铁氧体纳米杂化结构作为电磁波吸收剂，聚甲基丙烯酸甲酯（PMMA）为基体，制备出非晶碳纳米管/石墨烯/钡铁氧体纳米杂化结构改性PMMA复合材料。当吸波复合材料为单层结构时，纳米杂化结构改性树脂基复合材料的吸收频宽（<-10dB）达到最宽（3.6GHz）；当吸波复合材料为双层结构时，在2~18GHz范围内出现两个<-15dB的频率区域（6~10，11~18GHz），从而在多频段范围内吸收电磁波成为可能。项目重点以非晶碳纳米管/石墨烯/钡铁氧体纳米杂化结构作为吸收剂和PMMA为基体，采用机械压延法制备出非晶碳纳米管/石墨烯/钡铁氧体改性PMMA复合材料。在2~18GHz范围内，非晶碳纳米管/石墨烯/钡铁氧体改性PMMA复合材料电磁波吸收峰值为-28.9dB，吸收频宽（<-15dB）为8.08GHz；具有良好的电磁波吸收能力，能够大幅降低雷达散射截面(RCS)。基于经典电磁理论，建立了非晶碳纳米管电磁波路径损耗的数学模型，电磁波入射到非晶碳纳米管表面时，电磁波进入管壁内部，进行了多次反射，传播路径增长，路径损耗增大，从而大幅度提升非晶碳纳米管/石墨烯/钡铁氧体纳米杂化结构的电磁波吸收性能。.通过本项目研究，开拓了基于非晶碳纳米管/石墨烯/钡铁氧体纳米杂化结构改性树脂复合材料作为吸波材料在航空航天领域有着广泛的应用前景。