Study On The Preparation And Properties Of Broadband Absorption Light Structure Composites

Stealth technology has new"thin,light,wide and strong"performance requirements for absorbing materials.On single-layer materials,multi-layer composite materials have more flexible design possibilities.In this paper,the composite materials of reduced graphene oxide and Fe₃O₄ synthesized by green reducing agent and co-precipitation process can not only be produced on a large scale,but also have excellent electromagnetic wave absorption performance;The multilayer combination of quartz fiber,glass fiber and carbon fiber can provide good mechanical properties,corrosion resistance and constitute a wave-absorbing multilayer structure.In addition,FEKO?Arbitrarily Complex Electromagnetic Field Calculation?simulation and experimental tests were carried out on the multi-layer wave-absorbing composite material.The absorbing mechanism of single-layer and multi-layer absorbing composite materials was studied and the absorbing properties and absorbing mechanism of frequency-selective surface multilayer composite materials were explored.The main research contents and results are as follows:?1?It is confirmed by XRD,FT-IR,XPS that Fe₃O₄-rGO loss particles are synthesized,and Fe₃O₄ is mainly generated on the oxygen-containing functional group on the surface of rGO;The microscopic morphology of Fe₃O₄-rGO was determined by SEM,TEM and HRTEM;the Fe₃O₄-rGO composite particles were determined to be magnetic materials with soft magnetic properties by VSM;Through the study of the composition ratio and the reduction degree of graphene oxide,the ratio of the dielectric loss to magnetic loss and the dielectric loss polarization loss strength of the prepared lossy particles can be adjusted,thereby obtaining Fe₃O₄-rGO lossy particles with excellent electromagnetic properties.The VNA test results show that when the mass ratio of Fe₃O₄ to rGO is 8.7:1,there are multiple Debye relaxations,and the conductive loss is retained,and then combined with a certain eddy current loss and natural resonance and exchange resonance,the composite functional particle has a very good loss ability.The widest absorbing bandwidth reaches 7.04?9.63-16.67?GHz,and the strongest absorbing intensity is-21.04 dB.When the mass ratio of Fe₃O₄ to rGO is 2.9:1,it has the strongest absorbing intensity,which is-41.37 dB.?2?Simulate the absorbing performance of multi-layer materials by FEKO,and obtain the absorbing performance of single band?X band and Ku band?by controlling and simulating each layer of the wave transmitting layer,the wave absorbing layer and the reflecting layer.And through experiments to verify,the simulation results are similar to the experimental results,and the absorbing performance can cover almost the entire single frequency band.?3?Introduce the array structure on the surface of the double-layer composite material.The obtained multi-layer array structure composite material has an absorption peak of-13.21 dB at6.04 GHz,and the absorbing intensity gradually increases from 13.2 GHz and appears at 18GHz strong absorption of 31.99 dB.The effective absorption bandwidth is 6.75?5.43-7.11,12.93-18?GHz.The wavelength of electromagnetic waves in the high-frequency region is short,and it is easy to enter the array structure of the array-type multilayer absorber composite material,causing multiple reflections and scattering at the corners,thereby further enhancing the absorbency and achieving good absorption performance.