Hf、CNTs混合掺杂对纳米晶Sm_5Co_(19)合金结构和磁性能的影响  

Effect of Hf Elements and CNTs Alloy Mixed Doping on Structure and Magnetic Properties of Nanocrystalline Sm_5Co_(19) Alloy

作　　者：王东鑫 乔印凯 刘东 华刚 王海滨[1] 刘雪梅[1] 宋晓艳[1] Wang Dongxin, Qiao Yinkai, Liu Dong, Hua Gang, Wang Haibin, Liu Xuemei, Song Xiaoyan(Key Laboratory of Advanced Functional Materials, Ministry of Education, Beijing University of Technology, Beijing 100124, Chin)

机构地区：[1]北京工业大学新型功能材料教育部重点实验室,北京100124

出　　处：《稀有金属材料与工程》2018年第3期1001-1006,共6页Rare Metal Materials and Engineering

基　　金：国家自然科学基金(51371012;51425101)

摘　　要：对制备出纳米晶组织的Sm_5Co_(19)Hf_(0.4)合金和Sm_5Co_(19)Hf_(0.4)CNTs_(0.4)合金的显微组织、晶体结构和磁性能等进行了系统表征分析。结果表明:Hf元素和碳纳米管(CNTs)的混合添加不引起Sm_5Co_(19)合金Ce_5Co_(19)型结构发生相分解,且使纳米晶组织中的晶粒变得细小,晶粒尺寸均匀分布。能谱分析表明,添加的CNTs进入纳米晶Sm_5Co_(19)Hf_(0.4)CNTs_(0.4)合金的晶界区域,产生晶界钉扎作用,显著提高纳米晶Sm_5Co_(19)合金的矫顽力。晶体结构精修表明,Hf元素进入纳米晶Sm_5Co_(19)合金晶胞结构的Sm空位,导致晶格参数a、b、c均减小,而轴比c/a增加,使Hf掺杂的纳米晶合金的磁晶各向异性增大,具有提高纳米晶合金的矫顽力的作用。本研究结果对设计制备具有高磁晶各向异性、高内禀矫顽力的Sm-Co基合金具有明确指导意义。Permanent magnetic nanocrystalline Sm5Co19Hf0.4 alloy and Sm5Co19Hf0.4 CNTs0.4 alloy with high room-temperature coercivity were prepared. The microstructure, crystal structure and magnetic properties were studied. The results show that the mixed doping of Hf elements and CNTs does not lead to phase decomposition of Ce5Co19 type structure, while it results in fine grains and uniform distribution of the microstructure. Energy Dispersive X-ray Spectrometry（EDX） analyses confirm that CNTs move into grain boundaries of the nanocrystalline Sm5Co19Hf0.4 CNTs0.4 alloy, which can improve the coercivity of the nanocrystalline Sm5Co19 alloy for the grain boundary pinning effect. Rietyeld refinement show that Hf comes into the Sm vacancy, thus decreasing the lattice parameters and increasing the axial ratio c/a, which further enhance the magnetocrystalline anisotropy, and strengthen the coercivity of nanocrystalline alloy. The results of the study can promote the design of Sm-Co alloy with high magnetocrystalline anisotropy and intrinsic coercivity.

关 键 词：纳米晶合金 元素掺杂 晶体结构 原子占位 内禀矫顽力 

分 类 号：TG113.27[金属学及工艺—物理冶金]