中国物理B ›› 2017, Vol. 26 ›› Issue (5): 57502-057502.doi: 10.1088/1674-1056/26/5/057502

• CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES • 上一篇    下一篇

Influence of misch metal content on microstructure and magnetic properties of R-Fe-B magnets sintered by dual alloy method

Rong-Xiang Shang(商荣翔), Jie-Fu Xiong(熊杰夫), Dan Liu(刘丹), Shu-Lan Zuo(左淑兰), Xin Zhao(赵鑫), Rui Li(李锐), Wen-Liang Zuo(左文亮), Tong-Yun Zhao(赵同云), Ren-Jie Chen(陈仁杰), Ji-Rong Sun(孙继荣), Bao-Gen Shen(沈保根)   

  1. 1 State Key Laboratory of Magnetism, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China;
    2 University of Chinese Academy of Sciences, Beijing 100049, China;
    3 Key Laboratory of Magnetic Materials and Devices, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China
  • 收稿日期:2017-02-20 修回日期:2017-03-07 出版日期:2017-05-05 发布日期:2017-05-05
  • 通讯作者: Bao-Gen Shen E-mail:shenbg@aphy.iphy.ac.cn
  • 基金资助:

    Project supported by the National Key Research and Development Program of China (Grant Nos. 2014CB643702 and 2016YFB0700903), the National Natural Science Foundation of China (Grant No. 51590880), and the Knowledge Innovation Project of the Chinese Academy of Sciences (Grant No. KJZD-EW-M05).

Influence of misch metal content on microstructure and magnetic properties of R-Fe-B magnets sintered by dual alloy method

Rong-Xiang Shang(商荣翔)1,2, Jie-Fu Xiong(熊杰夫)1,2, Dan Liu(刘丹)1,2, Shu-Lan Zuo(左淑兰)1,2, Xin Zhao(赵鑫)1,2, Rui Li(李锐)1,2, Wen-Liang Zuo(左文亮)1,2, Tong-Yun Zhao(赵同云)1,2, Ren-Jie Chen(陈仁杰)2,3, Ji-Rong Sun(孙继荣)1,2, Bao-Gen Shen(沈保根)1,2   

  1. 1 State Key Laboratory of Magnetism, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China;
    2 University of Chinese Academy of Sciences, Beijing 100049, China;
    3 Key Laboratory of Magnetic Materials and Devices, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China
  • Received:2017-02-20 Revised:2017-03-07 Online:2017-05-05 Published:2017-05-05
  • Contact: Bao-Gen Shen E-mail:shenbg@aphy.iphy.ac.cn
  • Supported by:

    Project supported by the National Key Research and Development Program of China (Grant Nos. 2014CB643702 and 2016YFB0700903), the National Natural Science Foundation of China (Grant No. 51590880), and the Knowledge Innovation Project of the Chinese Academy of Sciences (Grant No. KJZD-EW-M05).

摘要:

MM14Fe79.9B6.1/Nd13.5Fe80.5B6 magnets were fabricated by dual alloy method (MM, misch metal). Some magnets have two Curie temperatures. Curie temperatures Tc1 corresponds to the main phase which contains more LaCe, and Tc1 decreases from 276.5 ℃ to 256.6 ℃ with the content of MM increasing from 30.3 at.% to 50.6 at.%. The variation of Br with the increase of MM indicates the existence of inter-grain exchange coupling in the magnets. When MM/R ≤ 30.3 at.%, the magnetic properties can reach the level of the intrinsic coercivity Hcj ≥ 7.11 kOe and the maximum energy product (BH)max ≥ 41 MGOe. Compared with Nd, La and Ce are easier to diffuse to the grain boundaries in the sintering process, and this will cause the decrease of Hcj. Due to the diffusion between the grains, the atomic ratio of La, Ce, Pr, and Nd in each grain is different and the percentage of Nd in all grains is higher than that in misch metal.

关键词: misch metal, multiple-main-phase, grain, permanent magnet

Abstract:

MM14Fe79.9B6.1/Nd13.5Fe80.5B6 magnets were fabricated by dual alloy method (MM, misch metal). Some magnets have two Curie temperatures. Curie temperatures Tc1 corresponds to the main phase which contains more LaCe, and Tc1 decreases from 276.5 ℃ to 256.6 ℃ with the content of MM increasing from 30.3 at.% to 50.6 at.%. The variation of Br with the increase of MM indicates the existence of inter-grain exchange coupling in the magnets. When MM/R ≤ 30.3 at.%, the magnetic properties can reach the level of the intrinsic coercivity Hcj ≥ 7.11 kOe and the maximum energy product (BH)max ≥ 41 MGOe. Compared with Nd, La and Ce are easier to diffuse to the grain boundaries in the sintering process, and this will cause the decrease of Hcj. Due to the diffusion between the grains, the atomic ratio of La, Ce, Pr, and Nd in each grain is different and the percentage of Nd in all grains is higher than that in misch metal.

Key words: misch metal, multiple-main-phase, grain, permanent magnet

中图分类号:  (High coercivity materials)

  • 75.50.Vv
75.50.Ww (Permanent magnets)