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GHz Electromagnetic Wave Absorption of Hexa and M-type Ferrite

六角和M型铁氧体的GHz电磁波吸收

基本信息

批准号：
09450254
负责人：
HOMMA Motofumi
金额：
$ 7.87万
依托单位：
TOHOKU UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1997
资助国家：
日本
起止时间：
1997 至 1999
项目状态：
已结题

项目摘要

Purpose : Recently, wireless communication tools such as mobile telephones and computer local area networks (LAN), have become very popular. However, as the number of systems using high frequency electromagnetic waves has increased, serious electromagnetic compatibility (EMC) problems have become apparent. This has led to the search for electromagnetic wave absorption materials for the use in the GHz range. In this study, the electromagnetic microwave absorption properties of Barium Hexa and M-type ferrite, in which FeィイD13+ィエD1 was substituted by (MeィイD20.5ィエD2MnィイD20.5ィエD2)ィイD13+ィエD1(Me=Sn, Ti, Zr), were investigated in the GHz frequency range.Experimental Procedure : Sintered samples were prepared by conventional powder metallurgy and composite samples were prepared by crushing these sintered bodies into powders (< 300μm) and mixing with an epoxy resin at different ratios from 40 to 80 mass%. The phases present in the samples were characterized by X-ray diffraction (XRD). The magnet … More ic properties were measured using a VSM and a magnetic balance. The electromagnetic wave absorption properties were measured using a Hewlett-Packard HP8510C network analyzer in the frequency range 0.05 to 20.05 GHz.Results : The anisotropy field (HィイD2AィエD2) of Barium M-type ferrite can be changed by varying the TiィイD20.5ィエD2MnィイD20.5ィエD2 content, which enables the natural resonance frequency (fr) to be controlled, in the range 48 GHz to 8 GHz. BaFeィイD212-xィエD2(TiィイD20.5ィエD2MnィイD20.5ィエD2)ィイD2XィエD2OィイD219ィエD2 sintered ferrites with compositions x = 2.5 to 5 exhibited good microwave absorption properties, with minimum reflection losses (R.L.) less than -20 dB in 1 to 20 GHz frequency range, for matching thicknesses (dm) of 0.5 to 3.8 mm. The ferrite-resin composites with 70 mass% ferrite, exhibited wide bandwidths with R.L. < -20dB. In particular, the composite samples with compositions x = 3 and x = 4 had wide bandwidths of 14.1 to 〜20GHz and 7.4 to 12.0 GHz, for matching thicknesses of 1.6 mm and 2.7mm, respectively. These matching thicknesses were smaller than for conventional spinel ferrites. It may be concluded that Barium M-type ferrite is a good candidate for a thin electromagnetic microwave absorber in the GHz range. Less

用途：最近，无线通信工具，如移动电话和计算机局域网（LAN），已经变得非常普及。然而，随着使用高频电磁波的系统数量的增加，严重的电磁兼容性（EMC）问题已经显现出来。这导致了对在GHz范围内使用的电磁波吸收材料的研究。在这项研究中,六钡的电磁微波吸收特性和斜铁素体,中菲ィイD13 +ィエD1代替了(我ィイD20.5ィエD2MnィイD20.5ィエD2)ィイD13 +ィエD1(我=锡、钛、锆、GHz频率范围进行调查。实验步骤：采用常规粉末冶金法制备烧结体，将烧结体粉碎成< 300μm的粉末，与环氧树脂按质量% 40 ~ 80%的比例混合，制备复合材料样品。用x射线衍射（XRD）对样品中存在的相进行了表征。使用VSM和磁天平测量了更多的ic特性。采用惠普HP8510C网络分析仪在0.05 ~ 20.05 GHz频率范围内测量了电磁波吸收特性。结果：通过改变钛（Ti）的含量，可以改变钡m型铁氧体的各向异性场（H φ φ D2A φ φ D2），使其自然共振频率（fr）在48 GHz ~ 8 GHz范围内得到控制。成分x = 2.5 ~ 5的BaFe φ φ D212-x φ φ d212 (Ti φ φ D20.5 φ φ D2Mn φ φ D20.5 φ D20.5 φ D2) φ φ D2X φ D2O φ D219 φ D2烧结铁氧体具有良好的微波吸收性能，在1 ~ 20 GHz频率范围内，匹配厚度（dm）为0.5 ~ 3.8 mm，最小反射损耗（rl）小于-20 dB。铁素体-树脂复合材料的铁素体质量为70%，具有较宽的带宽，rl < -20dB。其中，成分x = 3和x = 4的复合样品在匹配1.6 mm和2.7mm厚度时，带宽分别为14.1 ~ ~ 20GHz和7.4 ~ 12.0 GHz。这些匹配厚度小于传统尖晶石铁氧体。结果表明，m型钡铁氧体是GHz范围内薄型电磁微波吸收材料的理想候选材料。少