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Evaluation of Mechanical Properties for Spherical Magnetic Regenerator Materials Fabricated by Rapid Solidification Process

  • M. Okamura
  • N. Sori
  • T. Kuriyama
  • A. Saito
  • M. Sahashi
Part of the Advances in Cryogenic Engineering Materials book series (ACRE, volume 42)

Abstract

Various magnetic regenerator materials, such as Er3Ni, Er3Co and ErNi, are fabricated in the form of a spherical particle by a rapid solidification process. 4 K level refrigeration has been obtained by a GM refrigerator using these materials. However, the magnetic regenerator materials are considered brittle, as they are intermetallic compounds.

It is important to evaluate the mechanical properties of these materials to confirm reliability as a regenerator material. In this paper, experimental results of compression and vibration tests for magnetic regenerator materials are described. The technical point of this study is to use spherical particles as test samples.

The compressive stress of 20 MPa was applied to these spherical particles and no fractured spheres were observed. Similarly, no fractured spheres were found after the vibration test, in which the maximum acceleration was 30 × 9.8 m/s2 and the number of vibration times was 1 × 106, insofar as there was no room to stir spherical particles in a regenerator.

In practice, the reliability of magnetic regenerator materials has been confirmed by a long-run test of 7, 000 h in a usual GM refrigerator.

Keywords

Compressive Stress Intermetallic Compound Spherical Particle Maximum Acceleration Vibration Test 
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

  • M. Okamura
    • 1
  • N. Sori
    • 2
  • T. Kuriyama
    • 3
  • A. Saito
    • 3
  • M. Sahashi
    • 3
  1. 1.Materials and Devices Development CenterToshiba Co.Isogo-ku, YokohamaJapan
  2. 2.Material and Components Div.Toshiba Co.Isogo-ku, YokohamaJapan
  3. 3.Research and Development CenterToshiba Co.Saiwai-ku, KawasakiJapan

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