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

Matic Korent; Marko Soderznik; Urska Rocnik; Sandra Drev; Kristina Zuzek Rozman; Saso Sturm; Spomenka Kobe; Kristina Zagar Soderznik

doi:doi:10.11648/j.ijmsa.20211005.12

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

Matic Korent, Marko Soderznik, Urska Rocnik, Sandra Drev, Kristina Zuzek Rozman, Saso Sturm, Spomenka Kobe, Kristina Zagar Soderznik

Published in International Journal of Materials Science and Applications (Volume 10, Issue 5)

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

Matic Korent

Department for Nanostructured Materials, Jozef Stefan Institute, Ljubljana, Slovenia
Marko Soderznik

Department for Nanostructured Materials, Jozef Stefan Institute, Ljubljana, Slovenia
Urska Rocnik

Department for Nanostructured Materials, Jozef Stefan Institute, Ljubljana, Slovenia
Sandra Drev

Center for Electron Microscopy and Microanalysis, Jozef Stefan Institute, Ljubljana, Slovenia
Kristina Zuzek Rozman

Department for Nanostructured Materials, Jozef Stefan Institute, Ljubljana, Slovenia
Saso Sturm

Department for Nanostructured Materials, Jozef Stefan Institute, Ljubljana, Slovenia
Spomenka Kobe

Department for Nanostructured Materials, Jozef Stefan Institute, Ljubljana, Slovenia
Kristina Zagar Soderznik

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

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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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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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