| Absorbing materials with Carbon fiber structural have double function of loading and reducing the radar reflecting surface, which is the excellent microwave absorption material with integration function and structure.Carbon fiber absorbing materials have low resistivity and not have the magnetic loss, so it is not conducive to broaden the frequency band. In the paper, through doping and surface modification of carbon fiber, it can improve the comprehensive properties of carbon fiber absorbing wave materials.In this paper, through a combination of Laboratory of polyacryl onitrile (PAN) preparation technology of carbon fiber, reduced iron magnetic material was added in PAN, reacted with active elements of PAN, forming excellent ferromagnetic compounds, which improved the permea bility of composite materials, and obtained new carbon composite ab sorbing materials with dielectric loss and magnetic loss.In the aspect of magnetic selection of additives, the reduced ir on powder as the modified precursor was added to the PAN polyme rization in solution, and solidified in nitrogen atmosphere heat treat ment to obtain the carbon matrix composites. The results show that, one part of the the reduced iron powder added to the polymerizat ion of PAN fluid, can be reacted with a carboxyl PAN molecular ch ain and replaced H, another part to the elemental form of Fe, and is stable in thermal stabilization process. In the process of heat tr eatment, the Fe reacted with activated N and O elements in PAN macromolecular chain and generated magnetic compounds, which inc reased carbon matrix permeabilityIn this paper, multi-phase magnetic material was prepared is b eneficial to increase the interfacial polarization, dielectric constant o f the contribution is large, multiple resonance peaks in favor of per meability, broaden the absorption band. In this paper600℃,700℃,800℃temperature carbonization treatment carbon composite pe rformance of wave absorbing materials was characterized by SEM, c omposite surface and section morphology, by X ray diffraction analy sis of phase change before and after reaction; studied the influence of temperature on the electromagnetic properties of carbon carbon c omposite membrane by using vector network analyzer, effect of carb onization temperature and heat stable atmosphere studied the incorpo ration of PAN pre oxidation film reduced iron powder on the memb rane structure, electrical conductivity and dielectric properties, and e ffect of temperature and thermal stability of atmosphere carbonizatio n respectively on the dielectric properties of the films.SEM image analysis showed that, there is flaky nanometer mag netic material composite carbon membrane after carburization, and t he structure of carbon films for hollow internal external orifice. Thr ough the analysis of XRD spectra can be seen, there are graphite a nd Fe3O4composite carbon membrane was carbonized in nitrogen a tmosphere of existence, and nanometer-Fe particles, high temperatur e over700℃also appeared in Fe4N, and the higher the temperatu re, the higher Fe4N content. Wave absorbing properties test indicate d that, the dielectric constant of the composite carbon membranes s howed some dispersion effect, and carbonization temperature on the dielectric properties have a greater impact, with the carbonization te mperature increasing, the dielectric constant increases, carbonization temperature higher than700℃, in2～8GHz low frequency phase composite carbon the membrane permeability of little sensitivity to temperature, carbonization temperature is600℃composite carbon membrane permeability in9～10GHz resonance peak; in2～18GH z frequency band, the composite carbon membrane permeability of8 00℃imaginary part curve very small changes, fluctuations in the vicinity of0. |
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