Journal of Powder Materials (한국분말재료학회지)

The Korean Powder Metallurgy & Materials Institute (한국분말재료학회 (*구 분말야금학회))
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Improvement of the Magnetic Properties of (Nd, Dy)-Fe-B Sintered Magnets by Modification of HD and Annealing Processes

HD 처리 및 열처리공정 개선에 의한 (Nd, Dy)-Fe-B 소결자석의 자기특성 향상

  • NamKung, S. (Department of Materials and Metallurgical Engineering, Graduate School, Sunmoon University) ;
  • Lee, Y.H. (Department of Materials and Metallurgical Engineering, Graduate School, Sunmoon University) ;
  • Kim, M.K. (Department of Materials and Metallurgical Engineering, Graduate School, Sunmoon University) ;
  • Jang, T.S. (Department of Materials and Metallurgical Engineering, Graduate School, Sunmoon University)
  • 남궁석 (선문대학교 대학원 재료금속공학과) ;
  • 이연호 (선문대학교 대학원 재료금속공학과) ;
  • 김문갑 (선문대학교 대학원 재료금속공학과) ;
  • 장태석 (선문대학교 대학원 재료금속공학과)
  • Received : 2010.06.17
  • Accepted : 2010.08.19
  • Published : 2010.10.28
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Abstract

In an attempt to optimize the magnetic properties of (Nd, Dy)-Fe-B sintered magnets, hydrogenation and post-sintering heat treatment processes were investigated at various hydrogenation temperatures and heat treatment temperatures. The coercivity of (Nd, Dy)-Fe-B sintered magnets hydrogenated at $400^{\circ}C$ increased to about 1.2 kOe without any detrimental effect on the remanence. Moreover, the coercivity of the magnets was enhanced further by a consecutive $2^{nd}$ and $3^{rd}$ step heat treatment. These results eventually leaded to the reduction of the Dy content in a high coercive (> 30 kOe) (Nd, Dy)-Fe-B sintered magnets, as much as 10%.

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References

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