著者

杉本 諭 前田 徹 籠谷 登志夫 手束 展規 猪俣 浩一郎

出版者

公益社団法人 日本金属学会

雑誌

まてりあ (ISSN:13402625)

巻号頁・発行日

vol.42, no.3, pp.202-206, 2003-03-20 (Released:2011-08-11)

参考文献数

20

著者

杉本 諭 籠谷 登志夫 前田 徹

出版者

一般社団法人 粉体粉末冶金協会

雑誌

粉体および粉末冶金 (ISSN:05328799)

巻号頁・発行日

vol.53, no.3, pp.251-257, 2006 (Released:2006-08-18)

参考文献数

16

被引用文献数

1 2

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Recently, the use of microwaves in the GHz range has increased because of the demand for large data transmission. However, the problem of electromagnetic interference (EMI) has become serious, and much attention has been paid to microwave absorption materials. We have investigated magnetic loss of permanent magnet materials at natural resonance frequency, and have succeeded in the development of microwave absorbers using M-type (or W-type ferrite) and RE-Fe-B (RE: rare earth) compounds. The resonance frequency can be controlled by substitution of Fe3+ ion with other metal ion in the M-type or W-type ferrite. The resin composite of M-type ferrite shows wide bandwidth, in which the reflection loss (R.L.) is less than −20 dB. In the RE-Fe-B compounds, the substitution of RE with Sm or the fabrication of nanocomposite with a soft magnetic phase is effective method for controlling their resonance phenomena and functional frequency as microwave absorbers. The powder with fine α-Fe structure, which is produced by the disproportionation reaction of RE-Fe compounds, is useful for the filler of resin composite microwave absorbers in several GHz range.