根据电磁波传播规律, 设计了具有阻抗渐变结构的三层平板吸波体. 面层由二氧化钛材料组成, 易于实现与空气波阻抗匹配, 且起到一保护屏作用; 底层为强磁损耗体, 由铁、钴等原料, 经球磨而制得的磁性微粉, 形成对电磁波强大的损耗;中间层为过渡层, 构成从面层、中间层、底层的阻抗渐变结构. 采用磁性微粉与碳纤维按一定比例混合, 因而还具有一定的电磁损耗能力. 实验结果表明, 三层吸波体反射率在--8dB以下((8～18)GHz), 拉伸强度10.8MPa, 剥离强度75.2 N/cm, 满足一定的工程应用.
Based on the electromagnetic wave propagation laws, a three-layered sheet radar (microwave) absorbing system with the impedance-graded structure was designed. The surface layer, composed of TiO2, easily realizes matching to the free space and protection from destroying. The last layer, made up of magnetic micropowder (MMP) ballmilled from Fe, Co, etc, has significant absorbing effects. The medium layer, comprised of MMP and carbon fibers, forms the impedance-graded structure from the surface to the last layer. The results of experimental measurement show that reflectivity for the three-layer absorber is below --8dB in the frequency range of (8--18)GHz. Tensile strength is 10.8MPa, and peeling strength is 75.2N/cm, satisfying the use of engineering.
[1] 邢丽英, 蒋诗才, 李斌太. 复合材料学报, 2004, 21(6): 27--33.
[2] 赵东林, 沈曾民(ZHAO Dong-Lin, et al).无机材料学报(Journal of Inorganic Materials), 2005, 20(3): 608--612.
[3] 于晓凌. 层状各向同性与各向异性吸波材料设计与优化. 华中科技大学博士学位论文, 2002.
[4] He Yanfei, Gong Rongzhou, Nie Yan, et al. Journal of Applied Physics, 2005, 98(8): 084903-1.
[5] 吴明忠. 多晶铁纤维吸波特性研究.华中科技大学博士学位论文, 2000. 7--8.
[6] Chung Yeon-Choon, Kim Byung-Wook, Park Dong-Chul. IEEE Transactions on Magnetics, 2000, 36(4): 1188.
[7] 张殿荣,辛振祥.现代橡胶配方设计. 北京: 化学工业出版社, 2001. 24.
[8] 邢丽英, 刘俊能, 任淑芬. 材料工程, 1998, 1: 20.
