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)

Abstract

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.

Keywords

Rare Earth Metal Fine Wire Oxygen Contamination Centrifugal Atomization Wire Size 
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

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

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