中国物理B ›› 2013, Vol. 22 ›› Issue (1): 17502-017502.doi: 10.1088/1674-1056/22/1/017502

所属专题: TOPICAL REVIEW — Magnetism, magnetic materials, and interdisciplinary research

• SPECIAL TOPIC --- Non-equilibrium phenomena in soft matters • 上一篇    下一篇

Magnetic properties and magnetocaloric effects in NaZn13-type La(Fe, Al)13-based compounds

沈保根, 胡凤霞, 董巧燕, 孙继荣   

  1. State Key Laboratory for Magnetism, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
  • 收稿日期:2012-11-28 出版日期:2012-12-01 发布日期:2012-12-01
  • 基金资助:
    Project supported by the National Natural Science Foundation of China, the Key Research Program of the Chinese Academy of Sciences, the National Basic Research Program of China, and the National High Technology Research and Development Program of China.

Magnetic properties and magnetocaloric effects in NaZn13-type La(Fe, Al)13-based compounds

Shen Bao-Gen (沈保根), Hu Feng-Xia (胡凤霞), Dong Qiao-Yan (董巧燕), Sun Ji-Rong (孙继荣)   

  1. State Key Laboratory for Magnetism, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
  • Received:2012-11-28 Online:2012-12-01 Published:2012-12-01
  • Contact: Shen Bao-Gen E-mail:shenbg@aphy.iphy.ac.cn
  • Supported by:
    Project supported by the National Natural Science Foundation of China, the Key Research Program of the Chinese Academy of Sciences, the National Basic Research Program of China, and the National High Technology Research and Development Program of China.

摘要: In this article, our recent progress concerning the effects of atomic substitution, magnetic field, and temperature on the magnetic and magnetocaloric properties of the LaFe13-xAlx compounds are reviewed. With an increase of the aluminum content, the compounds exhibit successively an antiferromagnetic (AFM) state, a ferromagnetic (FM) state, and a mictomagnetic state. Furthermore, the AFM coupling of LaFe13-xAlx can be converted to an FM one by substituting Si for Al, Co for Fe, and magnetic rare-earth R for La, or introducing interstitial C or H atoms. However, low doping levels lead to FM clusters embedded in an AFM matrix, and the resultant compounds can undergo, under appropriate applied fields, first an AFM-FM and then an FM-AFM phase transition while heated, with significant magnetic relaxation in the vicinity of the transition temperature. The Curie temperature of LaFe13-xAlx can be shifted to room temperature by choosing appropriate contents of Co, C, or H, and a strong magnetocaloric effect can be obtained around the transition temperature. For example, for the LaFe11.5Al1.5C0.2H1.0 compound, the maximal entropy change reaches 13.8 J·kg-1·K-1 for a field change of 0-5 T, occurring around room temperature. It is 42% higher than that of Gd, and therefore, this compound is a promising room-temperature magnetic refrigerant.

关键词: La(Fe,Al)13 compounds, magnetocaloric effect, magnetic entropy change, magnetic phase transition

Abstract: In this article, our recent progress concerning the effects of atomic substitution, magnetic field, and temperature on the magnetic and magnetocaloric properties of the LaFe13-xAlx compounds are reviewed. With an increase of the aluminum content, the compounds exhibit successively an antiferromagnetic (AFM) state, a ferromagnetic (FM) state, and a mictomagnetic state. Furthermore, the AFM coupling of LaFe13-xAlx can be converted to an FM one by substituting Si for Al, Co for Fe, and magnetic rare-earth R for La, or introducing interstitial C or H atoms. However, low doping levels lead to FM clusters embedded in an AFM matrix, and the resultant compounds can undergo, under appropriate applied fields, first an AFM-FM and then an FM-AFM phase transition while heated, with significant magnetic relaxation in the vicinity of the transition temperature. The Curie temperature of LaFe13-xAlx can be shifted to room temperature by choosing appropriate contents of Co, C, or H, and a strong magnetocaloric effect can be obtained around the transition temperature. For example, for the LaFe11.5Al1.5C0.2H1.0 compound, the maximal entropy change reaches 13.8 J·kg-1·K-1 for a field change of 0-5 T, occurring around room temperature. It is 42% higher than that of Gd, and therefore, this compound is a promising room-temperature magnetic refrigerant.

Key words: La(Fe,Al)13 compounds, magnetocaloric effect, magnetic entropy change, magnetic phase transition

中图分类号:  (Magnetocaloric effect, magnetic cooling)

  • 75.30.Sg
75.50.Bb (Fe and its alloys)