Cryocoolers 8 pp 637-646 | Cite as

Development of a Magnetic Refrigerator Operating between 2 K and 10 K

  • A. Kashani
  • B. P. M. Helvensteijn
  • F. J. McCormack
  • A. L. Spivak
  • P. Kittel


A prototype adiabatic demagnetization refrigerator (ADR) operating between 2 K and 10 K has been built and tested. The refrigerant for the ADR is Gadolinium Gallium Garnet (GGG). In the design thick slices of single-crystal GGG are sandwiched together with strips of high-purity copper. The copper strips are used to transfer heat between the GGG and the 2 K and the 10 K heat switches. The heat switches employed in the ADR have no moving parts. The 10 K heat switch is a helium gas-gap heat switch; while, the 2 K heat switch is a He II-gap heat switch. Preliminary tests indicate that the prototype ADR can provide 27 mW of cooling at 2 K for 165 s; where, the cycle period is 12.6 minutes. The efficiency of the ADR relative to Carnot is 25%. Methods for improving the efficiency of the system are discussed.


Heat Sink Heat Load Heat Transfer Area Magnetic Refrigeration Heat Leak 
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Copyright information

© Springer Science+Business Media New York 1995

Authors and Affiliations

  • A. Kashani
    • 1
  • B. P. M. Helvensteijn
    • 2
  • F. J. McCormack
    • 3
  • A. L. Spivak
    • 3
  • P. Kittel
    • 4
  1. 1.Atlas ScientificSunnyvaleUSA
  2. 2.Sterling Federal SystemsPalo AltoUSA
  3. 3.Trans-Bay ElectronicsRichmondUSA
  4. 4.NASA-Ames Research CenterMoffett FieldUSA

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