한국분말재료학회지 (Journal of Powder Materials)

  • 제17권1호
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  • Pages.1-6
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  • 2010
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  • 2799-8525(pISSN)
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  • 2799-8681(eISSN)
한국분말재료학회 (*구 분말야금학회) (The Korean Powder Metallurgy & Materials Institute)
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Convergent 열처리를 통한Nd23Dy10Fe64TM2B1 소결자석의 보자력 향상

Coercivity Enhancement of Nd23Dy10Fe64TM2B1 Sintered Magnet by Convergent Heat Treatment

  • 김훈섭 (한양대학교 신소재공학과) ;
  • 김세훈 (한양대학교 신소재공학과) ;
  • 김진우 (한양대학교 신소재공학과) ;
  • 김영도 (한양대학교 신소재공학과)
  • Kim, Hoon-Sup (Department of Materials Science and Engineering, Hanyang University) ;
  • Kim, Se-Hoon (Department of Materials Science and Engineering, Hanyang University) ;
  • Kim, Jin-Woo (Department of Materials Science and Engineering, Hanyang University) ;
  • Kim, Young-Do (Department of Materials Science and Engineering, Hanyang University)
  • 발행 : 2010.02.28
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초록

In this study, a convergent heat treatment was performed in certain temperature regions in order to control the microstructures of Nd-rich phases and to reduce thermal stress on grain boundaries which could be caused during expansion and shrinkage of Nd-rich and $Nd_2Fe_{14}B$ phases. The difference of thermal expansion coefficient between $Nd_2Fe_{14}B$ and Nd-rich phases is the mechanism for convergent heat treatment. The Nd-rich phases which were located in junctions could penetrate into the grain boundaries between $Nd_2Fe_{14}B$ phases due to the difference of thermal expansion coefficient. Through the convergent heat treatment, the microcracks that were observed in cyclic heat treatment were not observed and coercivity was increased to 34.05 kOe at 8 cycles.

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