一种基于3D打印技术的结构型宽频吸波超材料  

Structural broadband absorbing metamaterial based on three-dimensional printing technology

作　　者：熊益军 王岩[1,2] 王强 王春齐[1,2] 黄小忠 张芬[2,3] 周丁 Xiong Yi-Jun;Wang Yan;Wang Qiang;Wang Chun-Qi;Huang Xiao-Zhong;Zhang Fen;Zhou Ding(Institute of Aeronautics and Astronautics, Central South University, Changsha 410012, China;Hunan Key Laboratory of Advanced Fibers and Composites, Changsha 410012, China;Institute of Physical and Electronic, Central South University, Changsha 410012, China)

机构地区：[1]中南大学航空航天学院,长沙410012 [2]新型特种纤维及其复合材料湖南省重点实验室,长沙410012 [3]中南大学物理与电子学院,长沙410012

出　　处：《物理学报》2018年第8期98-105,共8页Acta Physica Sinica

基　　金：湖南省科技计划(批准号:2015TP1007)资助的课题~~

摘　　要：设计了一种三层宽频吸波超材料,其表层和中间层为单元尺寸不同的周期阵列结构,底层为吸波平板结构,优化后的总厚度仅为4.7 mm,并采用三维(3D)打印技术成功制备了该吸波超材料.吸波体反射率测试结果表明,在电磁波垂直入射条件下,宽频吸收峰分别出现在5.3和14.1 GHz,两峰叠加使得其在4-18 GHz频率范围内反射损耗均小于-10 dB.采用S参数反演法计算了每一层的等效电磁参数,并利用多层结构反射率公式推导得出该模型的理论反射率,理论计算结果与实测结果基本一致.通过研究能量损耗、电场分布和磁场分布揭示了吸波机理,分析表明该吸波体的宽频吸收效果源于三层结构产生的吸收带宽叠加.本文提出的吸波超材料具有良好的宽频吸收效果,尤其在低频范围吸波性能较佳,结合3D打印快速成型技术,可获得结构精细的三层吸波超材料,具有重要的实际应用价值和广阔的应用前景.In order to verify the feasibility of three-dimensional（3 D） printing technology in preparing the metamaterial absorbers with complex structure, a three-layer broadband absorbing metamaterial is designed and fabricated by 3 D printing technology. The surface layer and middle layer of the metamaterial are composed of periodic arrays with different unit dimensions and the bottom layer of a slab structure. The optimized thickness of the metamaterial is 4.7 mm. A composite absorbent which consists of carbonyl iron powder and nylon is used to fabricate the absorber. In experiment,the obtained absorber is vertically irradiated by an electromagnetic（EM） wave. Two strong absorption peaks at 5.3 GHz and 14.1 GHz are achieved, with the reflection losses of-15.1 dB and-12.5 dB, respectively. The superposition of the two absorption peaks results in a reflection loss below-10 dB in a range from 4 to 18 GHz. The effective EM parameters of the surface layer and the middle layer are calculated by the S parameter inversion method. An effective model of the three-layer structure absorber is proposed and its reflectivity is calculated by using a multilayer structure reflectivity formula. The calculated reflectivity agrees well with the measured one. The absorbing and resonance mechanisms of the two absorption peaks are investigated by analyzing the dynamic distributions of power density loss, electric field and magnetic field. It can be clearly confirmed that the reflection losses at 5.3 GHz and 14.1 GHz are primarily concentrated on the bottom layer and surface layer, and the broadband absorption performance can be derived from the superposition of broadband absorptions of the three absorbing layers. Meanwhile, the strong electric coupling effect between the adjacent units in the surface layer is demonstrated by analyzing the electric-field distributions, which indicates that the strong reflection loss at 14.1 GHz is mainly caused by the electric response. The multiple scattering effects among the three layers are also con

关 键 词：吸波超材料 三维打印技术 宽频吸收 

分 类 号：TB34[一般工业技术—材料科学与工程]