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용융주조법으로 제조한 BSCCO-2212 초전도체의 공정변수 연구

Study on the Processing Variables of BSCCO-2212 Superconductor made by Melt Casting Process

  • 김규태 (성균관대학교 신소재공학부) ;
  • 장석헌 (성균관대학교 신소재공학부) ;
  • 임준형 (성균관대학교 신소재공학부) ;
  • 주진호 (성균관대학교 신소재공학부) ;
  • 김찬중 (한국원자력 연구소 원자력재료 기술개발팀) ;
  • 홍계원 (한국산업기술대학교 전기공학과) ;
  • 김혜림 (한국전력공사 전력 연구원) ;
  • 현옥배 (한국전력공사 전력 연구원)
  • Kim, Kyu-Tne (School of Advanced Materials Science and Engineering, Sungkyunkwan University) ;
  • Jang, Seok-Hern (School of Advanced Materials Science and Engineering, Sungkyunkwan University) ;
  • Lim, Jun-Hyung (School of Advanced Materials Science and Engineering, Sungkyunkwan University) ;
  • Joo, Jinho (School of Advanced Materials Science and Engineering, Sungkyunkwan University) ;
  • Kim, Chan-Joong (Nuclear Material Development Team, Korea Atomic Energy Research Institute) ;
  • Bong, Gye-Won (The Department of Electronic Engineering, Korea Polytechnic University) ;
  • Kim, Rye-Lim (Power System Laboratory, Korea Electric Power Research Institute) ;
  • Hyun, Ok-Bae (Power System Laboratory, Korea Electric Power Research Institute)
  • 발행 : 2005.06.01

초록

We fabricated BSCCO-2212 (2212) bulk superconductor by melt casting process, and evaluated the dependence of the critical properties on the temperature and cooling .ate of mold and the pouring methods of melt. It was observed that the critical current (Ic) of 2212 was significantly dependent on the pre-heating temperature of the mold. At the pre-heating temperature of $500^{\circ}C$ followed by air cooling condition, Ic of 48 A at 77 K was obtained which was higher than others processed at different temperatures. In addition, the Ic improved to 132 A when tilt casting method was applied. The improved Ic is probably due to the fact that the tilt casting reduced a turbulent flow of the melt during casting causing less porosity and more homogeneous microsructure. Critical temperature was measured to be 87-89 K after the first heat treatment and it improved to 90-91 K when subsequently heat treated at $650^{\circ}C$ in a nitrogen atmosphere. This improvement was considered to be due to an optimization of the oxygen content in the range of 8.16-8.2.

키워드

참고문헌

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