Progress in Superconductivity
- 제5권2호
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- Pages.124-127
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- 2004
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- 1229-4764(pISSN)
초전도 선재의 전 열처리에 따른 기계적 및 초전도 특성에 미치는 효과
Effect of pre-annealing conditions on mechanical and superconducting properties of Bi-2223/Ag tapes
초록
Many of research efforts have been focused on the improvement of critical current density (Jc) of silver-sheathed Bi-2223 tapes far practical applications. In this study, the transformation of Bi-2212 phase was investigated, which was transformed to orthorhombic from tetragonal through pre-annealing during powder packing and drawing process. The relationship between hardness of Bi-2212 orthorhombic phase and workability of Bi-2223/Ag tape was investigated. Bi-2223 superconducting wires with 55 filaments were fabricated by stacking and drawing process with different heat-treatment histories. Before rolling process, round wires were pre-annealing at 76