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Toward Low-Energy Spark-Plasma Sintering of Hot-Deformed Nd-Fe-B Magnets

Received: 24 August 2021     Accepted: 13 September 2021     Published: 29 September 2021
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Abstract

High-coercivity Nd-Fe-B permanent magnets are key materials for producing electrical components on the macro- and nanoscale. We present a newly developed, economically efficient method for processing Nd-Fe-B magnets based on spark-plasma sintering (SPS) that makes it possible to retain the technologically essential properties of the magnet, but by consuming about 30% less energy compared to the conventional SPS process. A magnet with an anisotropic microstructure was fabricated from MQU-F commercial ribbons with a low energy consumption (0.37 MJ) during the deformation process and compared to a conventionally prepared hot-deformed magnet that consumed three-times more energy (1.2 MJ). Both magnets were post-annealed at 650°C for 120 min in a vacuum. After the post-annealing process, the low-energy processing (LEP) hot-deformed magnet exhibited a coercivity of 1327 kAm-1, and a remanent magnetization of 1.27 T. In comparison, the high-energy processing (HEP) hot-deformed magnet had a coercivity of 1337 kAm-1 and a remanent magnetization of 1.31 T. A complete microstructural characterization and detailed statistical analyses revealed a better texture orientation for the HEP hot-deformed magnet processed with the larger energy consumption. This texture is the main reason for the difference in the remanent magnetization between the two hot-deformed magnets. The results show that although the LEP hot-deformed magnet was processed with three-times less energy than in a typical hot-deformation process, the maximum energy product is only 8% lower than that of a HEP hot-deformed magnet.

Published in International Journal of Materials Science and Applications (Volume 10, Issue 5)
DOI 10.11648/j.ijmsa.20211005.12
Page(s) 98-107
Creative Commons

This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited.

Copyright

Copyright © The Author(s), 2021. Published by Science Publishing Group

Keywords

Hot-Deformed Nd-Fe-B Magnets, Low-Energy Processing Hot-Deformation Process, Spark-Plasma Sintering, Statistical Analyses, Electron Microscopy

References
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    Matic Korent, Marko Soderznik, Urska Rocnik, Sandra Drev, Kristina Zuzek Rozman, et al. (2021). Toward Low-Energy Spark-Plasma Sintering of Hot-Deformed Nd-Fe-B Magnets. International Journal of Materials Science and Applications, 10(5), 98-107. https://doi.org/10.11648/j.ijmsa.20211005.12

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    ACS Style

    Matic Korent; Marko Soderznik; Urska Rocnik; Sandra Drev; Kristina Zuzek Rozman, et al. Toward Low-Energy Spark-Plasma Sintering of Hot-Deformed Nd-Fe-B Magnets. Int. J. Mater. Sci. Appl. 2021, 10(5), 98-107. doi: 10.11648/j.ijmsa.20211005.12

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    AMA Style

    Matic Korent, Marko Soderznik, Urska Rocnik, Sandra Drev, Kristina Zuzek Rozman, et al. Toward Low-Energy Spark-Plasma Sintering of Hot-Deformed Nd-Fe-B Magnets. Int J Mater Sci Appl. 2021;10(5):98-107. doi: 10.11648/j.ijmsa.20211005.12

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  • @article{10.11648/j.ijmsa.20211005.12,
      author = {Matic Korent and Marko Soderznik and Urska Rocnik and Sandra Drev and Kristina Zuzek Rozman and Saso Sturm and Spomenka Kobe and Kristina Zagar Soderznik},
      title = {Toward Low-Energy Spark-Plasma Sintering of Hot-Deformed Nd-Fe-B Magnets},
      journal = {International Journal of Materials Science and Applications},
      volume = {10},
      number = {5},
      pages = {98-107},
      doi = {10.11648/j.ijmsa.20211005.12},
      url = {https://doi.org/10.11648/j.ijmsa.20211005.12},
      eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ijmsa.20211005.12},
      abstract = {High-coercivity Nd-Fe-B permanent magnets are key materials for producing electrical components on the macro- and nanoscale. We present a newly developed, economically efficient method for processing Nd-Fe-B magnets based on spark-plasma sintering (SPS) that makes it possible to retain the technologically essential properties of the magnet, but by consuming about 30% less energy compared to the conventional SPS process. A magnet with an anisotropic microstructure was fabricated from MQU-F commercial ribbons with a low energy consumption (0.37 MJ) during the deformation process and compared to a conventionally prepared hot-deformed magnet that consumed three-times more energy (1.2 MJ). Both magnets were post-annealed at 650°C for 120 min in a vacuum. After the post-annealing process, the low-energy processing (LEP) hot-deformed magnet exhibited a coercivity of 1327 kAm-1, and a remanent magnetization of 1.27 T. In comparison, the high-energy processing (HEP) hot-deformed magnet had a coercivity of 1337 kAm-1 and a remanent magnetization of 1.31 T. A complete microstructural characterization and detailed statistical analyses revealed a better texture orientation for the HEP hot-deformed magnet processed with the larger energy consumption. This texture is the main reason for the difference in the remanent magnetization between the two hot-deformed magnets. The results show that although the LEP hot-deformed magnet was processed with three-times less energy than in a typical hot-deformation process, the maximum energy product is only 8% lower than that of a HEP hot-deformed magnet.},
     year = {2021}
    }
    

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  • TY  - JOUR
    T1  - Toward Low-Energy Spark-Plasma Sintering of Hot-Deformed Nd-Fe-B Magnets
    AU  - Matic Korent
    AU  - Marko Soderznik
    AU  - Urska Rocnik
    AU  - Sandra Drev
    AU  - Kristina Zuzek Rozman
    AU  - Saso Sturm
    AU  - Spomenka Kobe
    AU  - Kristina Zagar Soderznik
    Y1  - 2021/09/29
    PY  - 2021
    N1  - https://doi.org/10.11648/j.ijmsa.20211005.12
    DO  - 10.11648/j.ijmsa.20211005.12
    T2  - International Journal of Materials Science and Applications
    JF  - International Journal of Materials Science and Applications
    JO  - International Journal of Materials Science and Applications
    SP  - 98
    EP  - 107
    PB  - Science Publishing Group
    SN  - 2327-2643
    UR  - https://doi.org/10.11648/j.ijmsa.20211005.12
    AB  - High-coercivity Nd-Fe-B permanent magnets are key materials for producing electrical components on the macro- and nanoscale. We present a newly developed, economically efficient method for processing Nd-Fe-B magnets based on spark-plasma sintering (SPS) that makes it possible to retain the technologically essential properties of the magnet, but by consuming about 30% less energy compared to the conventional SPS process. A magnet with an anisotropic microstructure was fabricated from MQU-F commercial ribbons with a low energy consumption (0.37 MJ) during the deformation process and compared to a conventionally prepared hot-deformed magnet that consumed three-times more energy (1.2 MJ). Both magnets were post-annealed at 650°C for 120 min in a vacuum. After the post-annealing process, the low-energy processing (LEP) hot-deformed magnet exhibited a coercivity of 1327 kAm-1, and a remanent magnetization of 1.27 T. In comparison, the high-energy processing (HEP) hot-deformed magnet had a coercivity of 1337 kAm-1 and a remanent magnetization of 1.31 T. A complete microstructural characterization and detailed statistical analyses revealed a better texture orientation for the HEP hot-deformed magnet processed with the larger energy consumption. This texture is the main reason for the difference in the remanent magnetization between the two hot-deformed magnets. The results show that although the LEP hot-deformed magnet was processed with three-times less energy than in a typical hot-deformation process, the maximum energy product is only 8% lower than that of a HEP hot-deformed magnet.
    VL  - 10
    IS  - 5
    ER  - 

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Author Information
  • Department for Nanostructured Materials, Jozef Stefan Institute, Ljubljana, Slovenia

  • Department for Nanostructured Materials, Jozef Stefan Institute, Ljubljana, Slovenia

  • Department for Nanostructured Materials, Jozef Stefan Institute, Ljubljana, Slovenia

  • Center for Electron Microscopy and Microanalysis, Jozef Stefan Institute, Ljubljana, Slovenia

  • Department for Nanostructured Materials, Jozef Stefan Institute, Ljubljana, Slovenia

  • Department for Nanostructured Materials, Jozef Stefan Institute, Ljubljana, Slovenia

  • Department for Nanostructured Materials, Jozef Stefan Institute, Ljubljana, Slovenia

  • Department for Nanostructured Materials, Jozef Stefan Institute, Ljubljana, Slovenia

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