保磁力分布磁石の減磁曲線の推定法

カテゴリ: 論文誌(論文単位)

グループ名: 【A】基礎・材料・共通部門

発行日: 2012/01/01

タイトル(英語): Estimation of Demagnetization Curve of Magnet with Nonuniform Coercivity

著者名: 徳重　貴之（岡山大学工学部電気電子工学科），馬淵　聖史（岡山大学工学部電気電子工学科），宮城　大輔（岡山大学工学部電気電子工学科），高橋　則雄（岡山大学工学部電気電子工学科），伊藤　卓（信越化学工業（株）磁性材料研究所），廣田　晃一（信越化学工業（株）磁性材料研究所）

著者名(英語): Takayuki Tokushige (Department of Electrical and Electronic Engineering, Faculty of Engineering, Okayama University), Masafumi Umabuchi (Department of Electrical and Electronic Engineering, Faculty of Engineering, Okayama University), Daisuke Miyagi (Department of Electrical and Electronic Engineering, Faculty of Engineering, Okayama University), Norio Takahashi (Department of Electrical and Electronic Engineering, Faculty of Engineering, Okayama University), Masaru Ito (Magnetic Materials Research Center, Shin-Etsu Chemical Co., Ltd.), Koichi Hirota (Magnetic Materials Research Center, Shin-Etsu Chemical Co., Ltd.)

キーワード: 保磁力分布磁石，減磁曲線の推定　　coercivity distribution magnet，estimation of demagnetization curve

要約(英語): Neodymium-iron-boron (Nd-Fe-B) magnets exhibit exceedingly high maximum energy products and remanences. Their coercivities, however, decrease rapidly with increasing the temperature, and the magnets are easily demagnetized at elevated temperatures. To reduce the effects of temperature, the coercivity at the room temperature is enhanced by the addition of the dysprosium (Dy), which causes a reduction in remanence. The Grain Boundary Diffusion process is a technology to enhance coercivities while suppressing a large reduction in remanences. Dy that is effective for the coercivity enhancement is supplied from the magnet surface and diffused into the magnets through the grain boundary phase, and then put at the grain surface. When the Grain Boundary Diffusion process is applied to relatively large magnets, the partial coercivities near the magnet surface, where higher coercivities are generally required, can be enhanced effectively. In other words, the magnets exhibit nonuniform coercivity. We have conceived a simple and effective method for estimating the demagnetization curves of such nonuniform coercivity magnets. In this paper, the validity of the estimation method was examined.

本誌: 電気学会論文誌A（基礎・材料・共通部門誌） Vol.132 No.1 （2012） 特集：2012年研究開発の動向と最前線

本誌掲載ページ: 101-107 p

原稿種別: 論文／日本語

電子版へのリンク: https://www.jstage.jst.go.jp/article/ieejfms/132/1/132_1_101/_article/-char/ja/