Effective Anisotropy in Magnetically Nd2Fe14B/α-Fe Nanocomposite  

作　　者：郭家俊 陈雷 赵旭 范素丽 陈伟 

机构地区：[1]Department of Physics and Hebei Advanced Thin Film Laboratory, Hebei Normal University, Shijiazhuang 050016 [2]physics Teaching Office, Beijing Jiaotong University Halbin College, Huanghua 061100

出　　处：《Chinese Physics Letters》2010年第5期244-246,共3页中国物理快报（英文版）

基　　金：Supported by the National High Technology Research and Development Program of China under Grant No 2007AA03Z116, the Natural Science Foundation of Hebei Province （E2008000194）, and the Science Foundation of Hebei Education Department （2009133）.

摘　　要：Considering different contact situations of grains, we effective anisotropies of magnetically soft α-Fe grains, investigate the effects of exchange-coupling interaction on hard Nd2Fe14B grains and NdaFe14B/α-Fe nanocomposite. An expression of effective anisotropy suitable for different degrees of exchange-coupling between grains is presented. The calculation results show that the exchange-coupling interaction increases the average anisotropy of soft grains and decreases that of hard grains. The effective anisotropy of Nd2Fe14B/α-Fe nanocomposite decreases smoothly with decreasing grain size when the grain size is larger than 20 nm while it decreases dramaticaily with further decrease of the grain size. In order to maintain high coercivity in Nd2Fe14B/α-Fe nanoeomposite, the grain size should not be less than 20nm.Considering different contact situations of grains, we effective anisotropies of magnetically soft α-Fe grains, investigate the effects of exchange-coupling interaction on hard Nd2Fe14B grains and NdaFe14B/α-Fe nanocomposite. An expression of effective anisotropy suitable for different degrees of exchange-coupling between grains is presented. The calculation results show that the exchange-coupling interaction increases the average anisotropy of soft grains and decreases that of hard grains. The effective anisotropy of Nd2Fe14B/α-Fe nanocomposite decreases smoothly with decreasing grain size when the grain size is larger than 20 nm while it decreases dramaticaily with further decrease of the grain size. In order to maintain high coercivity in Nd2Fe14B/α-Fe nanoeomposite, the grain size should not be less than 20nm.

分 类 号：TM273[一般工业技术—材料科学与工程] TB332[电气工程—电工理论与新技术]