Journal of Materials Science

, Volume 51, Issue 7, pp 3390–3397 | Cite as

Effects of Hf on phase structure and magnetic performance of nanocrystalline SmCo7-type alloy

  • Gang Hua
  • Xiaoyan SongEmail author
  • Dong Liu
  • Dongxin Wang
  • Haibin Wang
  • Xuemei Liu
Original Paper


The effects of Hf doping on the phase constitution and its evolution of the SmCo7−x Hf x (0 ≤ x ≤ 0.5) nanocrystalline alloys were investigated. It was found that a single TbCu7-type metastable phase can be stabilized in the nanocrystalline SmCo7−x Hf x alloys with x ≤ 0.25, and the phase decomposition occurs at higher Hf doping contents. The Hf doping plays a significant role in inhibiting grain growth at high temperatures, which is favorable for the high-temperature magnetic properties. The metastable phase is stabilized by the combined effects of nanostructuring and Hf doping. Moreover, the magnetic performance is increased due to the pinning effect and the high magnetocrystalline anisotropy of the stabilized TbCu7-type phase.


Spark Plasma Sinter Nanocrystalline Alloy Magnetic Performance Spark Plasma Sinter Technique High Magnetocrystalline Anisotropy 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



This work was supported by the National Science Fund for Distinguished Young Scholars (51425101) and the National Natural Science Foundation of China (51371012).


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Copyright information

© Springer Science+Business Media New York 2015

Authors and Affiliations

  • Gang Hua
    • 1
  • Xiaoyan Song
    • 1
    Email author
  • Dong Liu
    • 1
  • Dongxin Wang
    • 1
  • Haibin Wang
    • 1
  • Xuemei Liu
    • 1
  1. 1.College of Materials Science and Engineering, Key Laboratory of Advanced Functional Materials, Ministry of Education of ChinaBeijing University of TechnologyBeijingChina

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