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Magnetic Hysteresis Properties and Microstructure of High-Coercivity (Nd,Dy)–Fe–B Magnets with Dy less than 10 wt % and Low Oxygen

  • ELECTRICAL AND MAGNETIC PROPERTIES
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Abstract

Magnetic properties and microstructure of (Nd,Dy)–Fe–B magnets with Dy in the range from 0 to 10.3 wt % and oxygen less than 0.26 wt % are studied. High-coercivity magnets with Dy 8 wt % have maximum energy density product (BH)max ≥ 35 MG Oe and coercivity МНс ≥ 30 kOe; their operating temperature can be as high as 180°С. Phase composition and structure of (Nd,Dy)–Fe–B magnets were studied by X-ray diffraction and scanning electron microscopy. In addition to the main (Nd,Dy)2Fe14B phase and (Nd,Dy)2O3 oxide, in triple junctions, there are two (Nd, Dy, Fe, М)Ox phases with fcc structure (symmetry group 225, Fm\(\bar {3}\)m) but with different content of O, Fe, and additional elements M (M = Co, Cu, Ga). It was shown that the total content of (Nd,Dy,Fe,М)Ox oxides grew with the total concentrations of oxygen and dysprosium in magnets.

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ACKNOWLEDGMENTS

Magnetic and structural properties were measured using equipment of Collaborative Access Center “Testing Center of Nanotechnology and Advanced Materials” IMP UB RAS.

Funding

Study of magnetic properties was performed in the framework of state assignment of the Ministry of Education and Science of Russia (theme “Magnet,” no. АААА-А18-118020290129-5). O.A. Golovnia is grateful to RSF project no. 21-72-10104 for support of study of microstructure and phase composition of samples.

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Authors and Affiliations

  1. Urals Electromechanical Plant, Joint-Stock Company, 620137, Ekaterinburg, Russia

    D. Yu. Vasilenko, A. V. Shitov, D. Yu. Bratushev & K. I. Podkorytov

  2. Mikheev Institute of Metal Physics, Ural Branch, Russian Academy of Sciences, 620108, Ekaterinburg, Russia

    A. V. Shitov, A. G. Popov, V. S. Gaviko & O. A. Golovnya

  3. Ural Federal University, 620002, Ekaterinburg, Russia

    A. G. Popov, V. S. Gaviko & O. A. Golovnya

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  1. D. Yu. Vasilenko
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  2. A. V. Shitov
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  3. A. G. Popov
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  4. V. S. Gaviko
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  5. D. Yu. Bratushev
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  7. O. A. Golovnya
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Correspondence to A. V. Shitov or O. A. Golovnya.

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Translated by O. Golovnya

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Vasilenko, D.Y., Shitov, A.V., Popov, A.G. et al. Magnetic Hysteresis Properties and Microstructure of High-Coercivity (Nd,Dy)–Fe–B Magnets with Dy less than 10 wt % and Low Oxygen. Phys. Metals Metallogr. 123, 145–154 (2022). https://doi.org/10.1134/S0031918X22020107

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