Iron Fiber Absorbing Materials Is Equivalent To The Prediction And Experimental Studies Of Electromagnetic Parameters

As a new radar absorbing materials, iron fiber has characteristics of light, wide frequency, and high permeability for its shape of anisotropy. The absorbing properties of iron fiber are more excellent than that of the conventional absorbing materials. Since the middle of 1980s, many foreign researchers have studied the iron fiber composites, made rapid development. Polycrystal iron fiber with excellent properties has been researched and developed and applied in practice. Much more attention has been paid to the research of iron fiber in our country, while more researches still are needed to be studied on how to control equivalent electromagnetic parameters and optimize it. We used the Strong Fluctuation Theory for analyzing the equivalent electromagnetic parameters and built the mathematic model. A coupled nonlinear equation system for solving the EM parameters is obtained. It can only be solved by iterative methods, because there are four coupled parameters ( ε', ε'', μ', μ'') and each corresponds to two unknown to be determined . The traditional iterative methods always give no proper results, so we select genetic algorithms to search the required results. According to the derived formula, we have designed the computer program with Visual C++ and got a series of useful rules. On the base of the theoretical analysis, we carried out the necessary experiment. And then we compared the experimental results with theoretical data. They coincide very well, it proved that our theoretical analysis is correct and can be used in practice. But limited by conditions, the fiber is stainless steel whose magnetism is weak. So we only analyze the dielectric property. Iron fiber absorber is conductor. With increasing the length and concentration of iron fiber, corresponding dielectric dissipation increases, so that good absorbing characteristics can't be designed. So the key technology is to reduce the dielectric dissipation of iron fibers. Coated fiber was used in this paper and expected effect was acquired by studying. The results and some rules in this paper have value for designing absorbing...