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Microstructure Regulation and Coercivity Improvement in the Dy2O3/WS2 Co-doped Nd-Fe-B–Sintered Magnets

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Abstract

In this study, the effects of Dy2O3/WS2 co-doping on magnetic properties and microstructure of Nd-Fe-B–sintered magnets were investigated. With WS2 addition, microstructure regulation and coercivity improvement were achieved in the Dy-containing magnets. The optimal magnetic performance was obtained in the 2 wt% Dy2O3/0.4 wt% WS2 co-doped magnets. The coercivity, remanence, and maximum energy product were 1727.1 kA/m, 1.211 T, and 286.5 kJ/m3, respectively. The coercivity was 10.5% higher than the WS2-free magnets, while there was no obvious change in the remanence and the maximum energy product. Relatively clear grain boundary phases were observed with smaller grain size. The average grain size of the co-doped magnets was 6.4 μm, which was about 1.6 μm smaller than the WS2-free magnets. More uniform Dy distribution was also obtained with the Nd2O2S phase formation. Besides, the W element likely precipitated at the grain boundaries.

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Funding

This study was supported by the China Postdoctoral Science Foundation (No. 2018 M641188). and the Fundamental Research Funds for the Central Universities (No. FRF-TP-18-025A1).

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Authors and Affiliations

  1. Institute for Advanced Materials and Technology, University of Science and Technology Beijing, Beijing, 100083, China

    Fang Yang, Qian Qin, Shengzeng Lin, Haixia Sun & Zhimeng Guo

  2. State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, Beijing, 100083, China

    Yanli Sui

  3. Department of Mechanical Engineering, University of South Florida, Tampa, FL, 33620, USA

    Alex A. Volinsky

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  1. Fang Yang
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  2. Qian Qin
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  3. Shengzeng Lin
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Correspondence to Fang Yang.

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Yang, F., Qin, Q., Lin, S. et al. Microstructure Regulation and Coercivity Improvement in the Dy2O3/WS2 Co-doped Nd-Fe-B–Sintered Magnets. J Supercond Nov Magn 33, 775–781 (2020). https://doi.org/10.1007/s10948-019-05258-7

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  • DOI: https://doi.org/10.1007/s10948-019-05258-7

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