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http://dx.doi.org/10.4283/JMAG.2016.21.1.051

Effect of Grain Boundary Modification on the Microstructure and Magnetic Properties of HDDR-treated Nd-Fe-B Powders  

Liu, Shu (Powder & Ceramics Division, Korea Institute of Materials Science)
Kang, Nam-Hyun (Department of Materials Science and Engineering, Pusan National University)
Yu, Ji-Hun (Powder & Ceramics Division, Korea Institute of Materials Science)
Kwon, Hae-Woong (Department of Materials Science and Engineering, Pukyong National University)
Lee, Jung-Goo (Powder & Ceramics Division, Korea Institute of Materials Science)
Publication Information
Abstract
The microstructure and magnetic properties of HDDR-treated powders after grain boundary diffusion process (GBDP) with Nd-Cu alloy at different temperatures have been studied. The variation of GBDP temperature had multifaceted influences on the HDDR-treated powders involving the microstructure, phase composition and magnetic performance. An enhanced coercivity of 16.9 kOe was obtained after GBDP at $700^{\circ}C$, due to the modified grain boundary with fine and continuous Nd-rich phase. However, GBDP at lower or higher temperature resulted in poor magnetic properties because of insufficient microstructural modification. Especially, the residual hydrogen induced phenomenon during GBDP strongly depended on the GBDP temperature.
Keywords
Nd-Fe-B magnets; HDDR; Nd-Cu alloy; residual hydrogen;
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1 J. F. Herbst, Rev. Mod. Phys. 63, 819 (1991).   DOI
2 S. Sugimoto, J. Phys. D: Appl. Phys. 44, 064001 (2011).   DOI
3 J. F. Herbst and W. B. Yelon. J. Appl. Phys. 57, 2343 (1985).   DOI
4 H. R. Cha, J. H. Yu, Y. K. Baek, 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).   DOI
5 H. R. Cha, J. H. Yu, Y. K. Baek, H. W. Kwon, Y. D. Kim, and J. G. Lee, J. Magn. 19, 49 (2014).   DOI
6 W. F. Li, T. Ohkubo, and K. Hono, Appl. Phys. Lett. 93, 052505 (2008).   DOI
7 R. Ramesh, G. Thomas, and B. M. Ma, J. Appl. Phys. 64, 6416 (1988).   DOI
8 K. Uestuener, M. Katter, and W. Rodewald, IEEE Trans. Magn. 42, 2897 (2006).   DOI
9 Y. Shinaba, T. J. Konno, K. Ishikawa, K. Hiraga, and M. Sagawa, J. Appl. Phys. 97, 053504 (2005).   DOI
10 J. D. Livingston, J. Appl. Phys. 57, 4137 (1985).   DOI
11 H. Sepehri-Amin, W. F. Li, T. Ohkubo, T. Nishiuchi, S. Hirosawa, and K. Hono, Acta Mater. 58, 1309 (2010).   DOI
12 J. Fidler, J. Magn. Magn. Mater. 80, 48 (1989).   DOI
13 H. Sepehri-Amin, T. Ohkubo, T. Nishiuchi, S. Hirosawa, and K. Hono, Scripta Mater. 63, 1124 (2010).   DOI
14 J. J. Ni, T. Y. Ma, and M. Yan, J. Magn. Magn. Mater. 323, 2549 (2011).   DOI
15 Z. Lin, J. Han, M. Xing, S. Liu, R. Wu, C. Wang, Y. Zhang, Y. Yang, and J. Yang, Appl. Phys. Lett. 100, 052409 (2012).   DOI
16 M. Takezawa, Y. Nagashima, Y. Kimura, Y. Morimoto, J. Yamasaki, N. Nozawa, T. Nishiuchi, and S. Hirosawa, J. Appl. Phys. 111, 07A714 (2012).   DOI
17 T. Nishiuchi, S. Hirosawa, M. Nakamura, M. Kakimoto, T. Kawabayashi, H. Araki, and Y. Shirai, IEEE Trans. Elec. Elec. Eng. 3, 390 (2008).   DOI
18 M. A. Matin, H. W. Kwon, J. G. Lee, and J. H. Yu, IEEE Trans. Magn. 50, 1 (2014).
19 W. F. Li, T. Ohkubo, K. Hono, T. Nishiuch, and S. Hirosawa, Appl. Phys. Lett. 93, 052505 (2008).   DOI
20 H. Sepehri-Amin, D. Prabhu, M. Hayashi, T. Ohkubo, K. Hioki, A. Hattori, and K. Hono, Scripta Mater. 68, 167 (2013).   DOI
21 M. Matin, H. W. Kwon, J. G. Lee, and J. H. Yu, J. Magn. 19, 106 (2014).   DOI
22 S. Nishio, S. Sugimoto, R. Goto, M. Matsuura, and N. Tezuka, Mater. Trans. 50, 723 (2009).   DOI
23 B. D. Cullity and C. D. Graham, Introduction to Magnetic Materials. Addison-Wesley, London (1972) pp. 360-362.