纳米复合永磁Pr_9Fe_(74)Co_(12)B_5Sn_x(x=0,0.5)的磁化行为与磁黏滞性  

Magnetization behavior and magnetic viscosity in nanocomposite Pr_9Fe_(74)Co_(12)B_5Sn_x(x=0,0.5) ribbons

作　　者：陈允忠[1] 贺淑莉[2] 张宏伟[1] 陈仁杰[1] 荣传兵[1] 孙继荣[1] 沈保根[1] 

机构地区：[1]中国科学院物理研究所磁学国家重点实验室,北京100080 [2]首都师范大学物理系,北京100037

出　　处：《物理学报》2005年第12期5890-5894,共5页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:10274102)资助的课题.~~

摘　　要：用熔体快淬法制备了纳米复合永磁样品Pr9Fe74Co12B5与Pr9Fe74Co12B5Sn0.5,分析了样品的起始磁化、反磁化过程,测得样品的总磁化率、可逆磁化率以及样品的磁黏滞性.结果表明,两样品在室温下均表现为单一硬磁相磁化行为,在低温下表现为双相行为,且由于添加Sn后使晶粒均匀化从而导致样品低温下的双相行为更加明显.添加Sn后引起样品中软磁相含量和软磁相晶粒尺寸的增加,使磁化反转中可逆磁化部分增多,且使反磁化形核场降低.磁黏滞性研究表明,热激活体积与软磁相晶粒的大小有关.Nanocomposite Pr9Fe74Co12B5 and Pr9Fe74Co12B5Sn0.5 ribbons were directly prepared by melt-spinning. Measurements of reversible and irreversible magnetization and magnetic viscosity were performed on the ribbons. It is found that the demagnetization curves of the both samples show a single hard phase behavior at room temperature, while a two-phase behavior at low temperature. The sample with Sn addition, because of its more homogeneous microstructure, shows a more obvious two-phase behavior than the Sn free one at low temperature. Furthermore, the increase of the volume fraction and grain sizes of the soft phase, in the Sn-doped ribbons, increases the portions of reversible magnetization and decreases the nucleation field Hn. The investigation of the magnetic viscosity shows that the activation volume is related to the grain sizes of the soft phase.

关 键 词：纳米复合永磁 磁化反转 磁粘滞 

分 类 号：O482.5[理学—固体物理]