Trend in Research and Development Related to Motors and Permanent Magnets for Solving Rare-earth Resources Problem

희토류 자원문제 해결을 위한 모터 및 영구자석 연구개발 동향

  • Lee, J.G. (Powder/Ceramics Division, Korea Institute of Materials Science) ;
  • Yu, J.H. (Powder/Ceramics Division, Korea Institute of Materials Science) ;
  • Kim, H.J. (Eco-Materials and Processing Department, Korea Institute of Industrial Technology) ;
  • Jang, T.S. (Department of Hybrid Engineering, Sunmoon University)
  • 이정구 (한국기계연구원 부설 재료연구소 분말/세라믹연구본부) ;
  • 유지훈 (한국기계연구원 부설 재료연구소 분말/세라믹연구본부) ;
  • 김휘준 (한국생산기술연구원 주조공정연구그룹) ;
  • 장태석 (선문대학교 하이브리드 공학과)
  • Received : 2012.03.05
  • Accepted : 2012.04.17
  • Published : 2012.04.30


Since Nd-Fe-B magnet was first synthesized in 1983, many new applications have emerged in the past two decades. With regard to motor market, it will expand because of strong energy saving requirements from the automobile and electric application markets. Especially, permanent magnet motors for hybrid and electric vehicles are drawing great attention and the usage of Nd-Fe-B magnets will increase all the more hereafter. There is, however, a serious problem as motors in such eco-friendly cars are said to operate in high temperatures of about $200^{\circ}C$. Nd-Fe-B magnet has a drawback of dramatically decreasing coercive force with the rise of temperature. In order to improve this aspect. the best way is to add dysprosium (Dy) into the magnet. So, Dy has become an essential element for Nd-Fe-B high-performance magnet as it helps to maintain coercive force even at high temperatures. On the other hand, the rare earth resources in the earth crust are eccentrically-located and its majority is produced in China. There is a need to reduce its usage as, especially compared to light rare earth elements as neodymium (Nd) and samarium (Sm), heavy rare earth elements including Dy are unevenly distributed to a dramatic degree, their output low, and their prices are about 10 times that of Nd. The present article includes a summary of the trend in research and development of motors and permanent magnets to solve rare-earth resources problem.


Supported by : 지식경제부


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