E. Z. Valiev, V. I. Bobrovskii

SPONTANEOUS VOLUME MAGNETOSTRICTION IN ANTIFERROMAGNETS AND ITS MANIFESTATION IN AN Fe–Rh ALLOY

A formula for spontaneous volume magnetostriction of a two-sublattice antiferromagnet is obtained and discussed in detail in terms of an exchange striction model. The main feature of the formula is taking into account the dependence of volumetric strains on the directions of sublattice magnetization vectors. The calculation shows that this way it is possible to explain giant forced
volume magnetostriction previously observed in the antiferromagnetic state of the Fe50Rh50 alloy. Besides, the temperature dependences of the specific volume and critical magnetic field of this alloy are calculated, and they are in a satisfactory agreement with the experiment.

Acknowledgment: The research was performed at the IMP Neutron Material Science Complex under the state assignment from the Ministry of Science and Higher Education of the Russian Federation (theme Flux, No. 122021000031-8).

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    Article reference

    Valiev E. Z., Bobrovskii V. I. Spontaneous Volume Magnetostriction in Antiferromagnets and Its Manifestation in An Fe–rh Alloy // Diagnostics, Resource and Mechanics of materials and structures. - 2024. - Iss. 5. - P. 170-180. -
    DOI: 10.17804/2410-9908.2024.5.170-180. -
    URL: http://eng.dream-journal.org/issues/2024-5/2024-5_472.html
    (accessed: 12/22/2024).