Development of Rare Earth Regenerator Materials in Fine Wire Form

  • T. Wong
  • J. M. Seuntjens
Part of the Advances in Cryogenic Engineering Materials book series (ACRE, volume 42)


The use of rare earth metals, both in the pure and alloyed state, have been examined for use as regenerators in cryocooler applications and as the working material in active magnetic refrigerators. In both applications there is a requirement for the rare earth material to have a constant and uniform cross section, an average size on the order of 50–200 microns in diameter, and low levels of impurities. Existing powder production methods have drawbacks such as oxygen contamination, non-uniform size, inconsistent cross sections, and low production yields. A novel approach for the production of rare earth metals and alloys in fine wire form has been developed. This is accomplished by assembling a copper jacket and niobium barrier around a RE ingot, extruding the assembly, and reducing it with standard wire drawing practices. Strand anneals are utilized between drawing passes when necessary in order to recrystallize the RE core and restore ductility. The copper jacket is removed by chemical means at final size, leaving the Nb barrier in place as a protective coating. This process has been applied to gadolinium, dysprosium and a GdDy alloy.


Rare Earth Metal Fine Wire Oxygen Contamination Centrifugal Atomization Wire Size 
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  1. 1.
    Liquid-free cryocoolers rearrange market equation for new applications, Superconductor Week, vol. 8(36), November 14, (1994).Google Scholar
  2. 2.
    W. A. Steyert, Stirling-cycle rotating magnetic refrigerators and heat engines for use near room temperature., J. Appl. Phys., 49(3), March (1978).Google Scholar
  3. 3.
    T. Kuriyama, R. Hakamada, H. Nakagome, Y. Tokai, M. Sahasi, R. Li, O. Yoshida, K. Matsumoto, and T. Hashimoto, High efficient two-stage GM refrigerator with magnetic material in the liquid helium temperature region, in: “Adv. in Cryo. Eng. vol. 35, ”Plenum Press, New York, (1990), p. 1261.Google Scholar
  4. 4.
    E. M. Ludeman and C. B. Zimm, Production of spherical powders of rare earth intermetallic compounds for use in cryocooler regenerators, in: “Adv. in Cryo. Eng. Vol. 37, Part B, ”Plenum Press, New York, (1992), p. 989.CrossRefGoogle Scholar
  5. 5.
    M. G. Osborne, I.E. Anderson, K.A. Gschneidner, M. J. Gailloux, and T. W. Ellis, Centrifugal atomization of neodymium and Er3Ni regenerator particulate, in: “Adv. in Cryo. Eng. Vol. 40, ”Plenum Press, New York, (1994), p. 631.Google Scholar
  6. 6.
    C. E. Reid, J. A. Barclay, J. L. Hall, and S. Sarangi, presented at the Twentieth Rare Earth Research Conference, Monterey, CA, Sept. 12–17 (1993).Google Scholar
  7. 7.
    Transition temperature from Dy-Gd magnetic phase diagram, Landolt-Bornstein, Numerical data and functional relationships in science and technology, New series III, Crystal and solid state physics, vol. 19, Magnetic properties of metals, H. P. J. Wign, ed. (1990).Google Scholar
  8. 8.
    C. B. Zimm, E. M. Ludeman, M. C. Stevenson, and T. A. Henning, Materials for regenerative magnetic cooling spanning 20K to 80K, in: “Adv. in Cryo. Eng. Vol. 37B, ”Plenum Press, New York, (1992), p. 883.CrossRefGoogle Scholar
  9. 9.
    K. A. Gschneidner, H. Takeya, J. O. Moorman, and V. K. Pecharsky, Appl. Phys Lett., 64(2), (1994)Google Scholar

Copyright information

© Springer Science+Business Media New York 1996

Authors and Affiliations

  • T. Wong
    • 1
  • J. M. Seuntjens
    • 1
  1. 1.Supercon, Inc.ShrewsburyUSA

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