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JOM

, Volume 67, Issue 6, pp 1350–1356 | Cite as

Thermal Activation in Permanent Magnets

  • S. Bance
  • J. Fischbacher
  • A. Kovacs
  • H. Oezelt
  • F. Reichel
  • T. Schrefl
Article

Abstract

The coercive field of permanent magnets decays with temperature. At non-zero temperatures, the system can overcome a finite energy barrier through thermal fluctuations. Using finite element micromagnetic simulations, we quantify this effect, which reduces coercivity in addition to the decrease of the coercive field associated with the temperature dependence of the anisotropy field, and validate the method through comparison with existing experimental data.

Keywords

Domain Wall Energy Barrier Permanent Magnet Coercive Field Magnetization Reversal 
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.

Notes

Acknowledgements

This paper is based on results obtained from the future pioneering program “Development of magnetic material technology for high-efficiency motors” commissioned by the New Energy and Industrial Technology Development Organization (NEDO). The authors would like to acknowledge funding support from the Replacement and Original Magnet Engineering Options (ROMEO) Seventh Framework Program (FP7).

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Copyright information

© The Minerals, Metals & Materials Society 2015

Authors and Affiliations

  • S. Bance
    • 1
  • J. Fischbacher
    • 1
  • A. Kovacs
    • 1
  • H. Oezelt
    • 1
  • F. Reichel
    • 1
  • T. Schrefl
    • 1
    • 2
  1. 1.Department of TechnologySt. Pölten University of Applied SciencesSt PöltenAustria
  2. 2.Center for Integrated Sensor SystemsDanube University KremsWiener NeustadtAustria

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