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Enhancement of coercivity in sintered Nd-Fe-B magnets by grain-boundary diffusion of electrodeposited Cu-Nd Alloys

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Abstract

We report an enhancement in the coercivity of sintered Dy free Nd-Fe-B magnets from 11.84 to 14.26 kOe by the grain-boundary diffusion of electrochemically deposited Cu-Nd. In the optimized electrochemical deposition and heat treatment conditions, a distinct Nd-rich grain-boundary phase was observed after the diffusion process; distributions of each element was carefully mapped by scanning electron microscopy equipped with backscattered electron detector. X-ray diffraction patterns indicated that Nd2Fe14B was oxidized by the inward diffusion of oxygen, which might be formed during the electrodeposition of Cu-Nd, forming antiferromagnetic Fe2O3 that might degrade the overall coercivity. A mechanism underlying the enhancement of coercivity is basically the same as the well-known proposed mechanism, distribution of a thin Nd-rich phase by grain-boundary diffusion process. In this study, electrochemical deposition process has been extensively investigated, and then the process was demonstrated to be successful and economically useful method to improve coercivity of the magnet.

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References

  1. K. Hirota, H. Nakamura, T. Minowa, and M. Honshima, IEEE T. Magn. 42, 2909 (2006).

    Article  Google Scholar 

  2. S. H. Kim, H. S. Kim, Y. J. Lee, D. G. Kim, and Y. D. Kim, Met. Mater. Int. 16, 959 (2010).

    Article  Google Scholar 

  3. H. R. Cha, J. G. Lee, Y. K. Back, J. H. Yu, H. W. Kwon, and Y. D. Kim, Korean J. Met. Mater. 51, 371 (2013).

    Google Scholar 

  4. J. Y. Kong, T. H. Kim, S. R. Lee, H. J. Kim, M. W. Lee, T. S. Jang, Met. Mater. Int. 21, 600 (2015).

    Article  Google Scholar 

  5. H. R. Cha, J. H. Yu, Y. K. Back. H. W. Kwon, T. H. Kim, C. W. Yang, T. S. Lim, Y. D. Kim, and J. G. Lee, Met. Mater. Int. 20, 909 (2014)

    Article  Google Scholar 

  6. F. Wan, J. Han, Y. Zhang, X. Zhang, J. Yang, and Y. Yang, J. Appl. Phys. 113, 193902 (2013).

    Article  Google Scholar 

  7. H. Sepehri-Amin, T. Ohkubo, T. Nishiuchi, S. Hirosawa, and K. Hono, Scripta. Mater. 63, 1124 (2010).

    Article  Google Scholar 

  8. W. B Cui, Y. K. Takahashi, and K. Hono, Acta Mater. 59, 7768 (2011).

    Article  Google Scholar 

  9. H. Sepehri-Amin, D. Prabhu, M. Hayashi, T. Ohkubo, K. Hioki, and A. Hattori, Scripta. Mater. 68, 167 (2013).

    Article  Google Scholar 

  10. T. Akiya, J. Liu, H. Sepehri-Amin, T. Ohkubo, K. Hioki, and A. Hattori, Scripta. Mater. 81, 48 (2014).

    Article  Google Scholar 

  11. H. Sepehri-Amin, T. Ohkubo, S. Nagashima, M. Yano, T. Shoji, and A. Kato, Acta Mater. 61, 6622 (2013).

    Article  Google Scholar 

  12. E. Isotahdon, E. Huttunen-Saarivirta, V. Kuokkala, M. Paju, and L. Frisk, J. Alloy. Compd. 585, 203 (2014).

    Article  Google Scholar 

  13. P. S. Monk and R. Partridge, J. Chem. Soc. Faraday. T. 93, 3991 (1997).

    Article  Google Scholar 

  14. P. S. Monk and R. Partridge, J. Chem. Soc. Faraday. T. 93, 3985(1997).

    Article  Google Scholar 

  15. R. Gopalan, H. Sepehri-Amin, K. Suresh, T. Ohkubo, K. Hono, T. Nishiuchi, N. Nozawa, and S. Hirosawa, Scripta. Mater. 61, 978 (2009).

    Article  Google Scholar 

  16. A. S. Kim and F. E. Camp, IEEE T. Magn. 31, 3620 (1995).

    Article  Google Scholar 

  17. T. Woodcock and O. Gutfleisch, Acta Mater. 59, 1026 (2011).

    Article  Google Scholar 

  18. T. Sasaki, T. Ohkubo, K. Hono, Y. Une, and M. Sagawa, Ultramicroscopy. 132, 222 (2013).

    Article  Google Scholar 

  19. J. Holc, S. Besenicar, and D. Kolar, J. Mater. Sci. 25, 219 (1990).

    Article  Google Scholar 

  20. B. B Straumal, Y. O. Kucheev, and I. L. Yatskovskaya, J. Mater. Sci. 24, 8359 (2012).

    Google Scholar 

  21. H. Sepehri-Amin, T. Ohkubo, T. Shima, and K. Hono, Acta Mater. 60, 819 (2012).

    Article  Google Scholar 

  22. X. Liu and Z. Altounian, IEEE T. Magn. 48, 3144 (2012).

    Article  Google Scholar 

  23. Y. Li, H. Evans, I. Harris, and I. Jones, Oxid. Met. 59, 167 (2003).

    Article  Google Scholar 

  24. K. S. Nam, S. K. Cho, and J. B. Kim, J. Kor. Soc. Magn. 22, 221 (2012).

    Article  Google Scholar 

  25. J. Y. Kong, T. H. Kim, S. R. Lee, H. J. Kim, M. W. Lee, and T. S. Jang, Met. Mater. Int. 21, 600 (2015).

    Article  Google Scholar 

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Authors and Affiliations

  1. Department of Advanced Circuit Interconnection, Pusan National University, Busan, 609-735, Republic of Korea

    Sangjun Lee, Jeehye Kwon & Dongyun Lee

  2. Powder & Ceramics Department, Korea Institute of Machinery & Materials, 66, Sangnam-dong, Changwon-city, Kyeongnam, 641-831, Republic of Korea

    Hee-Ryoung Cha & Junggoo Lee

  3. Department of Materials Science and Engineering, Pukyong National University, Busan, 608-739, Republic of Korea

    Kyung Min Kim & Hae-Woong Kwon

  4. Department of Nanoenergy Engineering, Pusan National University, Busan, 609-735, Republic of Korea

    Dongyun Lee

Authors
  1. Sangjun Lee
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  2. Jeehye Kwon
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  3. Hee-Ryoung Cha
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  4. Kyung Min Kim
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  5. Hae-Woong Kwon
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  6. Junggoo Lee
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  7. Dongyun Lee
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Correspondence to Dongyun Lee.

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Lee, S., Kwon, J., Cha, HR. et al. Enhancement of coercivity in sintered Nd-Fe-B magnets by grain-boundary diffusion of electrodeposited Cu-Nd Alloys. Met. Mater. Int. 22, 340–344 (2016). https://doi.org/10.1007/s12540-016-5460-8

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  • DOI: https://doi.org/10.1007/s12540-016-5460-8

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