Abstract The glass fiber epoxy composites containing MWCNTs and Fe3O4 NPs were manufactured by composites liquid molding process. The microwave absorbing properties of single-layered and double-layered glass fiber/MWCNTs/epoxy and glass fiber/Fe3O4 NPs/epoxy composites were evaluated. The reflection loss(RL) were calculated by the measured complex permittivity and permeability using waveguide method by vector network analyzer. Based on the mechanism analysis and deficiency of single-layer absorber, the double-layered composites were fabricated by using matching layer and absorbing layer to enhance the microwave absorption performance, which can be modulated by tailoring the electromagnetic parameters and thicknesses of each layer. The optimized microwave absorbing properties of double-layered composites with minimum RL of −45.7 dB and full X-band effective absorption can be achieved when the total thickness of the matching layer and absorbing layer is 1.8 mm, which can be attributed to synergistic effect of improved impedance matching characteristic and superior microwave attenuation characteristic of the absorbing layer. The combined utilization of dielectric loss and magnetic loss absorbent and their double-layered structure design shows great design flexibility and diversity and can be a promising candidate for designing high performance microwave absorbing materials.

中文翻译：

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通过双层设计含有 MWCNTs 和 Fe3O4 NPs 的玻璃纤维环氧树脂复合材料，在 X 波段实现完全有效的微波吸收

摘要 采用复合材料液态成型工艺制备了含有MWCNTs和Fe3O4 NPs的玻璃纤维环氧复合材料。评估了单层和双层玻璃纤维/MWCNTs/环氧树脂和玻璃纤维/Fe3O4 NPs/环氧树脂复合材料的微波吸收性能。反射损耗(RL)由矢量网络分析仪使用波导法测量的复介电常数和磁导率计算。基于单层吸收体的机理分析和不足之处，采用匹配层和吸收层制备双层复合材料，以提高微波吸收性能，可通过调整每层的电磁参数和厚度来调节微波吸收性能。最小RL为-45的双层复合材料的优化微波吸收性能。当匹配层和吸收层的总厚度为1.8mm时，可以实现7dB和全X波段的有效吸收，这是由于吸收层阻抗匹配特性提高和微波衰减特性优越的协同效应。介电损耗和磁损耗吸收剂的组合利用及其双层结构设计显示出极大的设计灵活性和多样性，可以成为设计高性能微波吸收材料的有希望的候选者。