Utilization of the Magnetic Entropy in Active Magnetic Regenerator Materials

  • K. A. GschneidnerJr.
  • V. K. Pecharsky
  • M. J. Gailloux
  • H. Takeya
Part of the Advances in Cryogenic Engineering Materials book series (ACRE, volume 42)

Abstract

The magnetic entropy associated with magnetic ordering has been determined for ~20 lanthanide materials and it varies from ~60 to ~90% of the theoretical Rln (2J+l) value. The utilization of this entropy in the magnetocaloric effect (MCE) for a 0 to 7.5 T field change, however, is much less, ranging from ~10 to ~30% at the Curie temperature (TC) for the 23 materials studied. At TC+100K the MCE is found to saturate and the magnetic entropy utilization increases up to ~20 to ~50%. These data indicate that lattice contribution to the heat capacity plays an important role in the magnetocaloric effect.

Keywords

Heat Capacity Curie Temperature Magnetocaloric Effect Magnetic Entropy Change Magnetic Refrigerant 
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

  • K. A. GschneidnerJr.
    • 1
  • V. K. Pecharsky
    • 1
  • M. J. Gailloux
    • 1
  • H. Takeya
    • 1
  1. 1.Ames Laboratory and Department of Materials, Science and EngineeringIowa State UniversityAmesUSA

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