Development of Microwave Absorber Composed of Dual Ferrite Phase

双铁氧体相微波吸收体的研制

基本信息

批准号：
13555183
负责人：
SUGIMOTO Satoshi
金额：
$ 4.35万
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：
2001
资助国家：
日本
起止时间：
2001 至 2002
项目状态：
已结题

项目摘要

[Purpose] In this study, sintered bodies composed of a mixture of M and W-type phases were prepared and their electromagnetic wave absorption properties were investigated. As its magnetic properties are similar to those of M-type ferrite, Zn added BaW-type ferrite (BaZn_2-W) was chosen for this work.[Experimental] The sintered body samples had composition of BaZn_<2x>Fe_<12-x+4y> (Sn_0.5>Mn_<0.5>)x O_<19+8y> (1.2≦x≦2.0, 0.25≦y≦0.75), and were sintered at temperatures between 1473 K and 1573 K. The phases present were analyzed by X-ray diffraction (XRD), and were shown to consist of BaM and BaZn2W-type hexaferrite phases. The relative complex permeability (μr′and μr″) and permittivity (εr′and εr″) of toroibally shaped sintered samples were calculated from S-parameter values measured using a Hewlett-Packard HP8720D network analyzer, in the frequency range 0.O5〜20.O5GHz.[Results] In all samples sinlered at 1473K〜1573K with x=1.2 and y=0.5, two peaks, corresponding to the M and W-type phases, were observed in the frequency dispersion of the relative complex permeability. In the T=1473K and 1523K samples, which showe Reflection Losses (R.L.) less than -2OdB, ΔF was 2.2 and 0.7GHz, respectively. Therefore, a sintering temperature of T=1473K was selected, and the compositional ratio of M and W phases (y) was varied between 0.25 and 0.75. Almost the same matching thickness (dm) was obtained for all of the samples, however the y=0.5 sample exhibited the largest ΔF value. Therefore, in the BaZnFe10.8(Sn0.5Mn0.5)1.2O23 sample sintered at 1473K, ΔF was wider (2.2GHz) than for a M-type single phase sintered body, with a relatively small matching thickness of dm=1.Omm. It is concluded that using a two-phase microstructure composed of M and W-type hexaferrite, is an effective method of expanding ΔF.

[目的] 本研究制备了M型和W型混合相的烧结体，并研究了其电磁波吸收性能，因为其磁性能与M型铁氧体相似，Zn添加BaW型。本工作选择铁氧体 (BaZn_2-W)。[实验] 烧结体样品的成分为 BaZn_<2x>Fe_<12-x+4y> (Sn_0.5>Mn_<0.5>)x O_<19+8y>(1.2≤x≤2.0，0.25≤y≤0.75)，并在1473K和1573K之间的温度下烧结。通过X分析存在的相。射线衍射（XRD），显示由 BaM 和 BaZn2W 型组成环形烧结样品的相对复磁导率（μr′和μr”）和介电常数（εr′和εr”）是根据使用惠普HP8720D网络分析仪测量的S参数值计算得出的。范围 0 .O5〜20.O5GHz。 [结果] 所有样品在 1473K〜1573K 下烧结x=1.2 和 y=0.5，在 T=1473K 和 1523K 样品中，在相对复数磁导率的频率色散中观察到对应于 M 型和 W 型相的两个峰值，这表明反射损耗 (R.L.) 较小。小于-2OdB，ΔF分别为2.2和0.7GHz，因此选择T=1473K的烧结温度， M相和W相的组成比(y)在0.25和0.75之间变化，所有样品都获得了几乎相同的匹配厚度(dm)，但是y=0.5的样品表现出最大的ΔF值。 BaZnFe10.8(Sn0.5Mn0.5)1.2O23 样品在 1473K 下烧结，ΔF 比M型单相烧结体，其匹配厚度相对较小，为dm=1.Omm。由此得出，采用M型和W型六方铁氧体组成的两相组织是扩大ΔF的有效方法。