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The Characterization of Nb3Sn Superconductors for Use in Magnets of 19 T and Greater

  • L. T. Summers
  • M. J. Strum
  • J. R. Miller
Part of the An International Cryogenic Materials Conference Publication book series (ACRE, volume 36)

Abstract

Increased resolution of NMR spectrometry will require the use of very high field Nb3Sn superconducting magnets. Here we report the results of our investigation into mechanical and temperature effects on internal-Sn superconductors similar to those proposed for use in a 900 MHz, 21 T NMR magnet system. Thermal precompression was found to be about 0.225%, and the irreversible strain was about 0.8%. Fatigue degradation was not observed at cyclic intrinsic strains below 0.575%. Additions of reinforcing steel in cable conductors was found to reduce the critical current by as much as 50% compared to similar, unreinforced cables. Reduction of the testing temperature to 2.3 K did not increase the critical current in steel-reinforced cables to a level significantly above that of unreinforced samples.

Keywords

Nuclear Magnetic Resonance Critical Current Applied Strain Steel Reinforcement Lawrence Livermore National Laboratory 
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References

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    R. W. Hoard, S.C. Manee, R.L. Leber, E.N.C. Dalder, M.R. Chaplin, K. Blair, D.H. Nelson and D.A. Van Dyke, “Field Enhancement of a 12.5 T Magnet Using Holmium Poles,” IEEE Trans. Mag., Vol. MAG-21, 448, 1985.CrossRefGoogle Scholar
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    M.J. Strum, L.T. Summers, and J.R. Miller, “Ductility Enhancement in Unreacted Internal-Sn Nb3Sn Through Low-Temperature Anneals,” IEEE Trans. Mag., Vol. 25, 2208, 1989.CrossRefGoogle Scholar
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Copyright information

© Plenum Press, New York 1990

Authors and Affiliations

  • L. T. Summers
    • 1
  • M. J. Strum
    • 1
  • J. R. Miller
    • 1
  1. 1.Lawrence Livermore National LaboratoryLivermoreUSA

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