The Preparation of Bi-2223 Superconducting Powder and Tape by Emulsion Drying Method

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J. Korean Ceram. Soc. > Volume 34(2); 1997 > Article

Journal of the Korean Ceramic Society 1997;34(2): 115.

에멀젼 건조법에 의한 Bi-2223 초전도 분말과 테이프 제조

장중철, 이응상, 이희균¹, 홍계원¹

한양대학교 무기재료공학과
¹한국 원자력 연구소 초전도 연구실

The Preparation of Bi-2223 Superconducting Powder and Tape by Emulsion Drying Method

ABSTRACT

The powder preparation by using emulsion drying method, one of the chemical powder fabrication methods has the advantages; easy to control the chemical stoichiometry and to fabricate homogeneously fine particles. In the present study, the initial morphology and size distribution of the powder fabricated by using emulsion dry-ing method were controlled and were improved the homogeneity. By carefully controlling the mixing ratio of oil phase and aqueous solution and surfactant of preventing emulsion separation, the Bi(Pb)-Sr-Ca-Cu-O su-perconducting powders were prepared. The properties of the superconducting powder fabricated by this method and the microstructures and superconducting properties of the pelletized samples were investigated. The microstructures and electric properties of the tapes prepared by oxide powder-in-tube method were in-vestigated. The fabricated powder was spherical with less than 1$mu$m but most of them was agglomerated with 2~5$mu$m in size. The critical temperature of the pelletized sample annealed at 84$0^{circ}C$ for 72 hours in oxygen par-tial pressure of 1/13atm in Ar atmosphere was 108K. And the critical current of the first and second annealed tapes in air prepared by oxide powder-in-tube process were 0.4A and 1.5A, respectively.

Key words: Emulsion drying method, Bi(Pb)-Sr-Ca-Cu-O superconducting powder, Critical temperature, Critical current