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

目的：近年来，移动电话和计算机局域网（LAN）等无线通信工具变得非常流行，但是，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）问题也变得越来越明显。这导致人们寻找在GHz范围内使用的电磁波吸收材料，在这项研究中，研究了六方钡和M型铁氧体的电磁微波吸收特性。将FeD13+D1替换为(MeD20.5D2MnD20.5D2)D13+D1(Me=Sn,Ti,Zr)，在GHz频率范围内进行研究。实验过程：采用常规粉末冶金方法制备烧结样品，并制备复合材料样品将这些烧结体粉碎成粉末（< 300μm）并以 40 至 80 质量% 的不同比例与环氧树脂混合，通过 X 射线衍射 (XRD) 来表征磁体特性。使用惠普 HP8510C 网络分析仪在 0.05 至 20.05 GHz 频率范围内测量波吸收特性。结果：各向异性场可以通过改变TiD20.5D2MnD20.5D2含量来改变钡M型铁氧体的(HiD2AD2)，从而能够将固有谐振频率(fr)控制在48GHz至8GHz范围内。 BaFe D212-x D2 (Ti D20.5 D2 Mn D20.5 D2) D2X D2O D219 D2 烧结铁氧体，成分 x = 2.5 至 5，具有良好的微波吸收性能，最小反射损耗 (R.L.) 小于 -20 dB (1)至 20 GHz 频率范围，用于匹配厚度 (dm) 为 0.5 至 3.8 mm 的铁氧体-树脂复合材料，显示出 R.L. < -20dB 的宽带宽。特别是，成分 x = 3 和 x = 4 的复合材料样品的宽带宽为14.1 至 ~20GHz 和 7.4 至 12.0 GHz，用于匹配 1.6 mm 和这些匹配厚度分别小于传统尖晶石铁氧体。可以得出结论，钡 M 型铁氧体是 GHz 范围内薄电磁微波吸收体的良好候选者。