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Mechanical Properties of High-Current Multifilamentary Nb3Sn Conductors

  • R. M. Scanlan
  • R. W. Hoard
  • D. N. Cornish
  • J. P. Zbasnik
Part of the Cryogenic Materials Series book series (CRYMS)

Abstract

Nb3Sn is a strain-sensitive superconductor which exhibits large changes in properties for strains of less than 1 percent. The critical current density at 12 T undergoes a reversible degradation of a factor of two for compressive strains of about 1 percent and undergoes an irreversible degradation for tensile strains on the Nb3Sn greater than 0.2 percent. Consequently, the successful application of Nb3Sn in large high-field magnets requires a complete understanding of the mechanical properties of the conductor. One conductor which is being used for many applications1–3 consists of filaments of Nb3Sn in a bronze matrix, and much progress has been made in understanding the mechanical behavior of this composite.4 The Nb3Sn filaments are placed in compression due to the differential thermal contraction between Nb3Sn and bronze which occurs when the composite is cooled from the Nb3Sn formation temperature (typically 700°C) to the 4.2 K operating temperature. The general behavior of the critical current when this conductor is subjected to a tensile stress is an increase to a maximum when the compressive strain on the Nb3Sn is relieved, followed by a decrease as the Nb3Sn filaments are placed in tension. The degree of precompression is controlled largely by the ratio of bronze to Nb3Sn in the conductor.5

Keywords

Compressive Strain Critical Current Effective Strain Nb3Sn Layer Bronze Matrix 
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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References

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Copyright information

© Plenum Press, New York 1980

Authors and Affiliations

  • R. M. Scanlan
    • 1
  • R. W. Hoard
    • 1
  • D. N. Cornish
    • 1
  • J. P. Zbasnik
    • 1
  1. 1.Lawrence Livermore National LaboratoryUniversity of CaliforniaLivermoreUSA

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