Advertisement

The Effect of Fabrication Variables on Filament Quality of Mono and Multifilamentary BSCCO-2212 Round Wires

  • M. Karuna
  • W. Zhang
  • E. E. Hellstrom
  • D. C. Larbalestier
Part of the Advances in Cryogenic Engineering Materials book series (ACRE, volume 42)

Abstract

Round silver-sheathed Bi2Sr2CaCu2Ox Mono and Multifilamentary Wires (19, 31 and 361 filaments) were made with and without extrusion and by drawing. Hexing the monofilaments at a smaller size led to better filament quality in the multifilamentary composites compared to hexing them at a larger size. Wires with a small Ag:BSCCO ratio (< 1:1) could not be drawn reliably with 20% reduction in area per pass but could be drawn at 10% per pass. However, using 10% reduction per pass in the multifilament stage created incipient center-burst defect problems and the final filament quality was degraded. Wires made from finer BSCCO powder had higher critical current density (Jc). The Jc of the better quality composites increased with decreasing filament diameter. Extrusion of multifilament stacks at room temperature and small reduction ratios (3:1) produced much better filament quality than extrusion at 250° C and larger ratios (10:1).

Keywords

Reduction Ratio Filament Size Filament Wire Filament Composite Filament Diameter 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    Pradeep Haldar and Leszek Motowidlo, Processing high critical current density Bi-2223 wires and tapes, J. Metals 10:54 (1992).Google Scholar
  2. 2.
    U. Balachandran, A.N. Iyer, P. Haldar, and L.R. Motowidlo, The powder-in-tube processing and properties of Bi-2223, J. Metals 9:54 (1993).Google Scholar
  3. 3.
    M. Karuna, J.A. Parrell, and D.C. Larbalestier, Study of powder density, Ag:superconductor ratio, and microhardness of BSCCO-2212 Ag-sheathed wires and tapes during wire drawing and rolling, IEEE Transactions on Applied Superconductivity 2:1279 (1995).CrossRefGoogle Scholar
  4. 4.
    The powder was obtained from Seattle Specialty CeramicsGoogle Scholar
  5. 5.
    L.R. Motowidlo, G. Galinski, G. Ozeryansky, W. Zhang and E.E. Hellstrom, Dependence of critical current density on filament diameter in round multifilament Ag-sheathed Bi2Sr2CaCu2Ox wires processed in 02, Appl. Phys. Lett. 21:2731 (1994).CrossRefGoogle Scholar
  6. 6.
    R. Wesche, A.M. Fuchs, B. Jakob and G. Pasztor, Diameter dependent critical current densities for superconducting Bi-2212/Ag wires, Cryogenics 10:803 (1994)Google Scholar
  7. 7.
    H.S. Edelman and D.C. Larbalestier, A test for gaussian critical current distributions in Bi2Sr2Ca2Cu3O10 and Nb-Ti superconducting wires, Advances in Cryogenic Engineering 40:749 (1993).Google Scholar

Copyright information

© Springer Science+Business Media New York 1996

Authors and Affiliations

  • M. Karuna
    • 1
    • 2
  • W. Zhang
    • 2
  • E. E. Hellstrom
    • 1
    • 2
  • D. C. Larbalestier
    • 1
    • 2
  1. 1.Materials Science ProgramUniversity of WisconsinMadisonUSA
  2. 2.Applied Superconductivity CenterUniversity of WisconsinMadisonUSA

Personalised recommendations