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Enhanced Proximity Effect Coupling Due to the Presence of a Nb Barrier in Fine NbTi Multifilamentary Composites

  • M. D. Sumption
  • H. Liu
  • E. Gregory
  • E. W. Collings
Part of the Advances in Cryogenic Engineering Materials book series (ACRE, volume 42)

Abstract

Recent measurements have shown that hydro-extruded fine-filament multifilamentary NbTi/Cu composite (MF) strands in which the NbTi filaments were not protected by Nb barriers exhibited extremely low proximity effect (PE) coupling. To examine this anomaly two series of MF strands were fabricated, one with and the other without the Nb barrier. Magnetization measurements performed on these strands confirmed that the presence of the Nb barrier was associated with an enhancement of the PE coupling. It is concluded that any additions to the matrix of a MF strand that would provide the needed protection against Cu/NbTi interface compound formation, without requiring the use of Nb as a barrier, can be expected to lower the tendency for PE coupling.

Keywords

Proximity Effect Filament Diameter Hydrostatic Extrusion Twist Pitch Strand Type 
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.

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Copyright information

© Springer Science+Business Media New York 1996

Authors and Affiliations

  • M. D. Sumption
    • 1
  • H. Liu
    • 2
  • E. Gregory
    • 2
  • E. W. Collings
    • 1
  1. 1.Department of Materials Science and EngineeringThe Ohio State UniversityColumbusUSA
  2. 2.IGC Advanced Superconductors Inc.WaterburyUSA

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