High Critical-Current Measurements in Liquid and Gaseous Helium

  • L. F. Goodrich
  • L. T. Medina
  • T. C. Stauffer
Part of the Advances in Cryogenic Engineering book series (ACRE, volume 44)


We compared variable-temperature critical-current, Ic(T), measurements up to 200 A on samples immersed in liquid helium to those on samples in flowing helium gas. Multifilamentary Nb-Ti and Nb3Sn samples were used in this study. Ic(T) measurements above 5 K are difficult because these measurements need to be done in helium gas and the heat generated during the measurement and conducted down high-current leads can raise the sample temperature significantly. This creates a large uncertainty and perhaps a sample dependent bias in the sample temperature that occurs even if the measurements are made meticulously. Ic(T) measurements at a constant magnetic field are needed to determine the temperature margin of magnet applications and performance data for cryogen-free applications. The comparison of Ic(T) data in liquid helium to data in gaseous helium, over the temperature range of 4 to 5 K, allows for the inference of sample temperature uncertainty and biases. Agreement to within 30 mK was obtained.


Critical Current Density Settling Time Pulse Method Liquid Data Current Contact 
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.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    L.F. Goodrich and S.L. Bray, High T, superconductors and critical current measurement, Cryogenics, Vol 30 (1990), p. 667–677ADSCrossRefGoogle Scholar
  2. 2.
    C.R. Spencer, P.A. Sanger, and M. Young, The temperature and magnetic field dependence of superconducting critical current densities of multifilamentary Nb3Sn and Nb-Ti composite wires, IEEE Trans. Magn, 15 (1979), p. 76–79ADSCrossRefGoogle Scholar
  3. 3.
    T. Ando, Y. Nunoya, N. Koizumi, M. Sugimoto, H. Tsuji, K. Sato, and Y. Yamada, Dependence of critical current density on temperature and magnetic field on in multifilamentary Nb3Al strands made by the Jerry Roll process, IEEE Trans. Appi. Supercond., (1997), p. 1568–1571Google Scholar
  4. 4.
    P.A. Hudson, F.C. Yin, and H. Jones, The critical current density of filamentary Nb3Sn as a function of temperature and magnetic field, IEEE Trans. Mag.,19 (1983), p. 903906Google Scholar
  5. 5.
    W. Schauer and F. Zimmermann, Temperature dependence of the critical current and pinning behavior for Nb3Sn filamentary superconductors, “Advances in Cryogenic Engineering Materials,” Vol. 26, Plenum Press, New York (1980), p. 432–441Google Scholar
  6. 6.
    L.F. Goodrich, D.F. Vecchia, E.S. Pittman, J.W. Ekin, and A.F. Clark, “Critical current measurements on a Nb-Ti superconducting wire standard reference material,” Nat. Bu. Stands. (U.S.) Spec. Publ. 260–91, (September 1984)Google Scholar

Copyright information

© Springer Science+Business Media New York 1998

Authors and Affiliations

  • L. F. Goodrich
    • 1
  • L. T. Medina
    • 1
  • T. C. Stauffer
    • 1
  1. 1.National Institute of Standards and TechnologyBoulderUSA

Personalised recommendations