硬磁CoFe_2O_4/软磁CoFe_2复合物的磁性研究  

Investigation on the magnetic properties of hard CoFe_2O_4/soft CoFe_2 composites

作　　者：马永青[1] 黄松[1] 徐士涛[1] 

机构地区：[1]安徽大学物理与材料科学学院,安徽合肥230601

出　　处：《安徽大学学报（自然科学版）》2016年第1期37-41,共5页Journal of Anhui University(Natural Science Edition)

基　　金：国家自然科学基金资助项目(51471001;11174004);安徽大学2014年大学生科研训练计划项目(KYXL2014025)

摘　　要：采用金属有机盐热分解方法制备出均匀、分散的硬磁CoFe_2O_4纳米颗粒,在H2环境、低温条件下进行还原,合成硬磁CoFe_2O_4/软磁CoFe_2复合磁体.采用低温还原,目的在于尽可能减少粒子的聚集.制备出的样品具有较好的磁性能:有较高的剩磁比Mr/Ms,其值为0.64;随着还原时间延长,饱和磁化强度增加至124emu·g^(-1),同时保持较高的矫顽力.分析认为,可以通过减弱粒子间的偶极相互作用来有效提高硬磁/软磁复合磁体的矫顽力和剩磁比.Well-dispersed uniform hard magnetic CoFe2O4 nanoparticles were synthesized by thermal decomposition of a metal-organic salt.Then they were reduced in H2 ambient at low temperature to prepare hard CoFe2O4/soft CoFe2 composites in order to weaken as possibly the agglomeration.The improved magnetic performances were obtained in this work：a higher remanence to saturation magnetization ratio Mr/Msvalue of 0.64 was obtained;with increasing the reducing time the Msvalue greatly increases to 124emu·g-1 with the smaller loss of coercivity Hc.Through analysis it could be suggested that the Hcand Mr/Msvalues could be effectively improved by decreasing the strength of the dipolar interaction.

关 键 词：磁性纳米粒子 CoFe2O4/CoFe2复合磁体 偶极相互作用 

分 类 号：TM27[一般工业技术—材料科学与工程]