基于图案化和超表面结构制备高效宽频吸波材料

Preparation of Efficient Broadband Absorbing Materials Based on Patterning and Metamaterial Surface

用羰基铁粉/高密度聚乙烯(CIP/HDPE)和碳纳米管/高密度聚乙烯(CNTs/HDPE)2种复合材料构造了多层吸波材料,通过仿真和实验对其吸波性能进行研究。结果表明,不同材料叠加优于单一吸波材料。进一步对多层吸波材料的顶层及中间层进行图案化设计,既降低了整体结构的质量,又通过多模式共振、吸波单元的界面和边缘衍射拓宽了吸收频带。在不影响吸波材料整体厚度的基础上,通过嵌入2层方形金属谐振单元提高微波吸收性能,制备的超材料吸波体在厚度为7.5 mm时,实现了2.85~18 GHz的高效宽带吸收。

Two composite materials of carbonyl iron powder/high density polyethylene(CIP/HDPE)and carbon nanotubes/high density polyethylene(CNTs/HDPE)were used to construct a multilayer absorbing material,and the absorbing performance was studied through simulation and experiment.The results show that the multilayer material is better than a single layer absorbing material.Further pattern design of the top and middle layers of the multilayer absorbing material not only reduces the mass of the overall structure,but also broadens the absorption bandwidth through multimode resonance,interface and edge diffraction of the absorbing units.Without affecting the overall thickness of the absorbing material,the resonance absorption introduced by the two layers of square metal patches further broadens the absorption bandwidth of the absorbing material,the prepared metamaterial absorber achieves a high-efficiency broadband absorption of 2.85~18 GHz at the thickness of 7.5 mm.