The magnetization reversal behaviour for SmCo_(6.8)Zr_(0.2) and SmCo_(6.8)Zr_(0.2)/α-(Fe,Co) nanocrystalline magnets at low temperature

作     者：刘壮 陈仁杰 李东 闫阿儒 

作者机构：Zhejiang Province Key Laboratory of Magnetic Materials and Application TechnologyNingbo Institute of Material Technology & EngineeringChinese Academy of Sciences Institute of Solid State PhysicsChinese Academy of Sciences 

出 版 物：《Chinese Physics B》 (中国物理B（英文版）)

年 卷 期：2010年第19卷第6期

页      面：528-533页

核心收录：

学科分类：080801[工学-电机与电器] 0808[工学-电气工程] 08[工学] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学] 

基　　金：Project supported by the Natural Science Foundation of Zhejiang Province of China (Grant No.Y407174) Major Scientific and Technological Special Fund of Zhejiang Province of China (Grant No.2007C11046) the National Basic Research Program of China (Grant No.2010CB934601) 

主　　题：nanocrystalline magnets coercivity mechanism inter-grain exchange coupling magne- tization reversal behaviour 

摘      要：This paper reports that the SmCo6.8Zr0.2 nanocrystalline permanent magnets and SmCo6.8Zr0.2/a-（Fe,Co） nanocomposite permanent magnets are successfully produced by mechanical alloying and subsequently annealing at 700℃ for 10 minutes. The x-ray diffraction results show that the phase structure of SmCo6.8Zr0.2 nanocrystalline permanent magnets is composed of SmCo7 phase and SmCo6.8Zr0.2/a-（Fe,Co） nanocomposite permanent magnets is composed of SmCo7 and a-（Fe,Co） phases. The mechanism of magnetization reversal is mainly controlled by inhomogeneous domain wall pinning in SmCo6.8Zr0.2 and SmCo6.8Zr0.2/a-（Fe,Co） magnets. The inter-grain exchange interaction at low temperature is investigated, which shows that the inter-grain exchange interaction of SmCo6.8Zr0.2/a-（Fe,Co） magnets increases greatly by the decrease of the measured temperature. According to Amirr-H/Hcj, Amrev-H/Hcj and Xirr-H/Hcj curves at room temperature and 100 K, the changes of irreversible and reversible magnetization behaviours of SmCo6.8Zr0.2 and SmCo6.8Zr0.2/a-（Fe,Co） magnets with the decreasing temperature are analysed in detail. The magnetic viscosity and the activation volume of SmCo6.8Zr0.2 and SmCo6.8Zr0.2/a-（Fe,Co） magnets at different temperatures are also studied.