Study On Absorbing Properties Of Composite Laminate Structure

The twenty-first century has been called the information technology community, with the rapid development of science technology and military high-tech,the technology require the development of absorbing material tends to strong absorption,light weight, broadband,infrared and microwave absorption compatible and overall performance better, Currently modification research of a large number of traditional layer absorbing material is not meet this requirement, while structure absorbing materials is an effective way to achieve this technical requirements, given the composites has light quality high strength, very design able and other characteristics, so this article had researched multi-functional structure composite which had absorbing properties.This paper studieds on the absorbing properties of the monolayer fiber reinforced composites of vinyl resin filled with G(graphite),as well as the the absorbing properties of the bilayer structure of MnO2(manganese dioxide)/G,CI(carbonyl iron)/G, BF(nano-barium ferrite)/I (iron-based) and three-layer structure of MnO2/CI/G respectively.It is fund by studying on the monolyaer graphite structure composites that the maximum absorption peaks are shifted to lower frequency with the increase the content of graphite and material thickness.the maximum reflectivity of the sample is-16.8 dB at about 11.9GHz and the practical effective bandwidth (R<-10 dB) is about 3 GHz,.the structure: material thickness is 4.7mm, the content of graphite is 15Wt%. On this basis, bilayer absorbing materials with resistance gradual changing stureture (matchinglayer+absorbinglayer)are designed with MnO2 or CI as the matching layer and with G as the absorbing layer.The eleetromagnetic parameter is controlled by the content of the absorbent in the matching layer to achieve the resistance matching between the surface of the bilayer material and the air interface; adjusting the content of the bottom absorbent to acquire maximum attenuation and absorption, the absorption efficiency is improved by this structure.Findings show that the samples in the frequency range 8-18 GHz, the model of MnO2/G maximum absorption is-12.3dB, the effective bandwidth is 1.8GHz, the structure:the content of MnO2 in the matching layer is 20Wt%and the thickness is 1.3mm; the content of G in the absorbing layer is 35Wt%and the thickness is 3.5mm.The model of CI/G maximum absorption is-20. 1dB, the effective bandwidth is 7GHz, its structure:the content of CI in the matching layer is 20Wt%and thickness is 1.4mm; the content of G in the absorbing layer is 35Wt%and the thickness is 3.4mm.Three layer structure of MnO2/CI/G absorbing materials was orthogonal experimental designed based on bilayer absorbing materials,the optimal design:the content of MnO2 in the matching layer is 30Wt%,the content of CI in the middle layer is 20Wt%,the content of G in the absorbing layer is 40Wt%.This combination have good absorbing properties, the maximum absorption is -29.1 dB, the effective bandwidth is 6.6 GHz.Nanomaterials become a hot research in the absorbing material field as itself have many unique properties,so this paper researched the absorbing properties of the bilayer structure of BF/I at last,nanoparticles was managed by two decentralized processing, the maximum absorption of the sample is -7.1dB in the frequency range 26.5-40 GHz.This paper is an important foundation research for the structure absorbing materials, laying the foundation for further studying the structure absorbing materials,pointing out the clear direction for launching successor activity, it has practical guide; study of several structural absorbing material, has better absorbing properties, and has some practical value.