中国物理B ›› 2019, Vol. 28 ›› Issue (7): 77503-077503.doi: 10.1088/1674-1056/28/7/077503

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

Regulating element distribution to improve magnetic properties of sintered Nd-Fe-B/Tb-Fe-B composite magnets

Zhu-Bai Li(李柱柏), Jing-Yan Zuo(左敬燕), Dong-Shan Wang(王东山), Fei Liu(刘飞), Xue-Feng Zhang(张雪峰)   

  1. 1 Key Laboratory of Integrated Exploitation of Bayan Obo Multi-Metal Resources, Inner Mongolia University of Science and Technology, Baotou 014010, China;
    2 School of Science, Inner Mongolia University of Science and Technology, Baotou 014010, China
  • 收稿日期:2019-01-13 修回日期:2019-05-06 出版日期:2019-07-05 发布日期:2019-07-05
  • 通讯作者: Zhu-Bai Li E-mail:lzbgj@163.com
  • 基金资助:

    Project supported by the National Natural Science Foundation of China (Grant Nos. 51861030 and 51571126) and the National Key Research and Development Program of China (Grant No. 2016YFB0700900).

Regulating element distribution to improve magnetic properties of sintered Nd-Fe-B/Tb-Fe-B composite magnets

Zhu-Bai Li(李柱柏)1,2, Jing-Yan Zuo(左敬燕)1, Dong-Shan Wang(王东山)2, Fei Liu(刘飞)1,2, Xue-Feng Zhang(张雪峰)1,2   

  1. 1 Key Laboratory of Integrated Exploitation of Bayan Obo Multi-Metal Resources, Inner Mongolia University of Science and Technology, Baotou 014010, China;
    2 School of Science, Inner Mongolia University of Science and Technology, Baotou 014010, China
  • Received:2019-01-13 Revised:2019-05-06 Online:2019-07-05 Published:2019-07-05
  • Contact: Zhu-Bai Li E-mail:lzbgj@163.com
  • Supported by:

    Project supported by the National Natural Science Foundation of China (Grant Nos. 51861030 and 51571126) and the National Key Research and Development Program of China (Grant No. 2016YFB0700900).

摘要:

Nd content was varied in Nd13.2-xFe80.8+xB6 (x=0, 0.5, 1, and 1.5) to optimize the magnetic properties of sintered Nd-Fe-B/Tb-Fe-B composite magnets, which were prepared by mixing 9 g of Nd-Fe-B with 1 g of Tb17Fe75B8 powder. In conventional magnets, by reducing Nd content, the coercivity of 10.4 kOe in Nd13.2Fe80.8B6 decreases to 7.2 kOe in Nd12.2Fe81.8B6; meanwhile, in Nd-Fe-B/Tb-Fe-B magnets the coercivity does not decrease when reducing Nd content. In the intergranular phase, the Tb content increases owing to the reducing Nd content of the Nd-Fe-B alloy in the sintered composite magnets. Therefore, the excess Tb in Tb17Fe75B8 enters the intergranular phase, and more Tb atoms can substitute for Nd at the grain boundary of the Nd-Fe-B phase, leading to a more significant increase in coercivity. The remanence increases with reducing Nd content, and the energy product of 39.1 MGOe with a high coercivity of 21.0 kOe is obtained in Nd12.2Fe81.8B6/Tb17Fe75B8 magnets. These investigations show that magnetic properties can be further improved by regulating the element distribution in sintered composite magnets.

关键词: composite magnets, coercivity, intergranular phase, element distribution

Abstract:

Nd content was varied in Nd13.2-xFe80.8+xB6 (x=0, 0.5, 1, and 1.5) to optimize the magnetic properties of sintered Nd-Fe-B/Tb-Fe-B composite magnets, which were prepared by mixing 9 g of Nd-Fe-B with 1 g of Tb17Fe75B8 powder. In conventional magnets, by reducing Nd content, the coercivity of 10.4 kOe in Nd13.2Fe80.8B6 decreases to 7.2 kOe in Nd12.2Fe81.8B6; meanwhile, in Nd-Fe-B/Tb-Fe-B magnets the coercivity does not decrease when reducing Nd content. In the intergranular phase, the Tb content increases owing to the reducing Nd content of the Nd-Fe-B alloy in the sintered composite magnets. Therefore, the excess Tb in Tb17Fe75B8 enters the intergranular phase, and more Tb atoms can substitute for Nd at the grain boundary of the Nd-Fe-B phase, leading to a more significant increase in coercivity. The remanence increases with reducing Nd content, and the energy product of 39.1 MGOe with a high coercivity of 21.0 kOe is obtained in Nd12.2Fe81.8B6/Tb17Fe75B8 magnets. These investigations show that magnetic properties can be further improved by regulating the element distribution in sintered composite magnets.

Key words: composite magnets, coercivity, intergranular phase, element distribution

中图分类号:  (High coercivity materials)

  • 75.50.Vv
75.50.Ww (Permanent magnets) 75.60.Ej (Magnetization curves, hysteresis, Barkhausen and related effects)