三层石墨烯吸波体熔融沉积成形及层间材料分布对吸波性能的影响

Forming of Three-layer Graphene Absorber by Fused Deposition Modeling and Effect of Interlayer Material Distribution on Microwave Absorption Properties

利用熔融沉积成形技术快速制备了石墨烯/聚乳酸和石墨烯/四氧化三铁/聚乳酸两类复合吸波材料和三层石墨烯吸波体,测试了复合材料的电磁参数,计算了反射率;利用CST仿真与实验研究了吸波剂层间分布及孔洞结构对三层石墨烯吸波体吸波性能的影响。结果表明:对复合材料而言,双组元吸波剂的吸波性能更佳,但难以与石墨烯单组元吸波剂形成良好的阻抗匹配;对三层石墨烯吸波体而言,石墨烯呈均匀梯度分布(石墨烯加入量分别为5%、7%、9%(均为质量分数,下同)),可获得最佳的吸波效果;周期性孔洞结构的存在,一方面增加了反射界面数量,产生更多的边缘散射效应与多重共振耦合,另一方面通过改善阻抗匹配使石墨烯呈非均匀梯度分布(石墨烯加入量分别为7%、7%、9%)时实现Ku波段(12~18 GHz)全覆盖有效吸收(反射率小于-10 dB),为微波频段高效吸收提供了参考。

Graphene/polylactic acid and graphene/Fe3O4/polylactic acid composites and three-layer graphene absorbers were rapidly prepared by fused deposition modeling technology.The electromagnetic parameters of the composites were measured and the reflectivity was calculated.The effects of interlayer distribution and pore structure of absorber on the microwave absorbing properties of three-layer graphene absorber were studied by CST simulation and experiment.It is found that for the composites,the two-component absorber has better microwave absorption performance,but it is difficult to form a good impedance match with the graphene one-component absorber.For the three-layer graphene absorber,graphene presents a uniform gradient distribution(The addition amount of graphene is 5%,7%and 9%respectively),which can obtain the best absorbing effect.The existence of periodic hole structure,on the one hand,increases the number of reflection interfaces,resulting in more edge scattering effects and multiple resonance coupling.On the other hand,by improving impedance matching,it can realize full coverage effective absorption(reflectivity less than-10dB)in Ku band(12—18GHz)when graphene is distributed in a non-uniform gradient(The addition of graphene is 7%,7%and 9%respectively).It provided a reference for efficient absorption in microwave band.