Journal of Magnetics

The Korean Magnetics Society (한국자기학회)
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Coercivity Enhancement in Nd2Fe14B Permanent Magnetic Powders through Rotating Diffusion Process with DyHx Powders

  • Choi, Moon-Hee (Energy Materials Lab., School of Materials Science and Engineering, Pusan National University) ;
  • Yu, Ji-Hun (Functional Materials Powder Technology Group, Korea Institute of Material Science) ;
  • Kim, Dong-Hwan (Functional Materials Powder Technology Group, Korea Institute of Material Science) ;
  • Kim, In-Bae (Energy Materials Lab., School of Materials Science and Engineering, Pusan National University) ;
  • Kim, Yang-Do (Energy Materials Lab., School of Materials Science and Engineering, Pusan National University)
  • Received : 2011.09.05
  • Accepted : 2011.10.10
  • Published : 2011.12.31
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Abstract

[ $Nd_2Fe_{14}B$ ]permanent magnetic powders ($_iH_c$ = 9.2 kOe, $B_r$ = 12.2 kG) were produced by HDDR process. Their coercivity was enhanced to 12.6 kOe through the grain boundary diffusion process with dysprosium hydride ($DyH_x$). $DyH_x$ diffusion process was optimized through rotating diffusion process, resulting in distinct phases rich in Nd and Dy observable by field emission scanning microscopy and transmission electron microscopy. The mechanism of coercivity enhancement that resulted in restrain the coupling effect between $Nd_2Fe_{14}B$ grains is also discussed.

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