The Research On The Electromagnetic Wave Shielding Property Of Carbon Filaments Arrangement And Their Complex Arrangements

Selecting various types of carbon fiber assemblies which included different arrangements of carbon filaments of Expanded Polystyrene (EPS) sheets, carbon filaments woven and knitted fabrics and chopped carbon filaments composites. This paper regarded different arrangements of carbon filaments as a main body of research and studies the effect of different arrangement on Shielding Effectiveness (SE) and shielding mechanism.The experiments discussed the effect of the factors of space, carbon content and buckling wave amplitude on the shielding property of different arrangement carbon filaments EPS sheet. The results showed that:The peak value of carbon filaments parallel and buckling waved arrangement with different space mainly focus in the ends of measured frequency, the smaller the space, the better the SE was. The peak value of carbon filaments grid arrangement with different space mainly focus in the middle of measured frequency, the smaller the space, the better the SE was. The test makes parallel, buckling waved and grid arrangement EPS sheet of2K,3K and4K with the space of10mm, and from the experiment it can be found that the SE of samples increases along with the increase of carbon content,in addition the shape of curves with different content were nearly the same. For buckling waved arrangement, the whole SE was the biggest when the buckling wave amplitude is2H. On the whole, the increase of buckling wave amplitude h led to increase in the quality of carbon fiber and thickness of absorption, on the other hand,which also lead to increase of EMW incident angle and the angle between the surface of waved filament. Thus enhance the effect of scattering in its double reverse impact. And there was a trend of2H> H>3H on absorption property absorbing property of2H>H>3H, where it existed extreme value. According to the SE test on carbon filaments woven and knitted fabrics and chopped carbon filaments composites, it can be found that their SE differ greatly in the whole frequency and the general SE is not very good. Therefore, this paper studied the SE of double-faced of single arrangement of single layer, buckling and grid mulriple arrangement of single layer and four layers mulriple arrangement EPS sheet. The results showed that the SE of crossed buckling and six complex arrangement sheets increased on the whole frequency from0.05～2.0GHz, and the average value of SE was10dB, and the peak value of crossed buckling and grid arrangement braiding sheet was24.5dB and the average of which was18.11dB.It can be found that the frequency affected SE greatly due to the analysis on buckling waved arrangement model and significant influence analysis, so it introduced the index of area of effective SE which was S to evaluate the SE of samples comprehensively. It made integration in three frequency bands to evaluate buckling arrangement EPS sheet because of its SE variance was huge in the measured frequency. The results shows that S of samples was good in the high frequency and was bad in the middle frequency on the whole. It mad integration in the whole frequency bands to evaluate complex arrangement sheets because of their SE variance was small. The results showed among all the samples the S of braiding sheet was the best and the stratified arrangement sheet was the worst. When it refered to the complex arrangements, configuration of arrangement which meant secondary lattice structure plays an main role in the shielding mechanism.