Effect of Pre-Sintering on the Diffusion Treatment of HRE for Coercivity Enhancement of a NdFeB Sintered Magnet

• Autorzy: Lee M. W. , Lee J. K. , Jang T. S.

Identyfikatory

DOI

10.24425/amm.2019.127584

• Języki publikacji: EN

Abstrakty

EN

We investigated the effect of pre-sintering process on the penetration behavior of Dy in a NdFeB sintered magnet which was grain boundary diffusion treated with Cu/Al mixed Dy source. The pre-sintering of a magnet was performed at 900°C in vacuum and then the pre-sintered body was dipped in the solutions of DyH₂, DyH₂ + Cu, and DyH₂ + Al, respectively. The dipped pre-sintered body were then fully sintered 4 hours at 1060°C followed by a subsequent annealing. The pre-sintering apparently improved the diffusivity of Dy atoms. The penetration of Dy into the magnet extended almost to 2,000 μm from the surface, about four times deeper than that of the normally sintered and diffusion treated one, when the DyH₂ + Al solution was used as a Dy source. However, the resulting increase of coercivity was about 4 kOe, somewhat lower than that of the normally treated one, mostly due to excessive oxide formation that hindered to make a continuous Nd-rich grain boundary phase and a core-shell type structure.

Słowa kluczowe

EN

grain boundary diffusion process; GBDP; NdFeB magnet; coercivity; pre-sintering

• Wydawca: Institute of Metallurgy and Materials Science of Polish Academy of Sciences ; Committee of Materials Engineering and Metallurgy of Polish Academy of Sciences
• Czasopismo: Archives of Metallurgy and Materials
• Rocznik: 2019
• Tom: Vol. 64, iss. 2
• Strony: 597--601
• Opis fizyczny: Bibliogr. 17 poz., fot., rys., tab.

Twórcy

autor

Lee M. W.

• Sunmoon University, Dept. of Advanced Materials Engineering, Asan, Chungnam 336-708, Korea

autor

Lee J. K.

• Sunmoon University, Dept. of Advanced Materials Engineering, Asan, Chungnam 336-708, Korea

autor

Jang T. S.

• Sunmoon University, Dept. of Advanced Materials Engineering, Asan, Chungnam 336-708, Korea

Bibliografia

• [1] K.H.J. Buschow, J. Mater. Sci. Res. 1, 1 (1986).
• [2] J. F. Herst, Rev. Mod. Phys. 63, 819 (1991).
• [3] J. Fidler, J. Bernardi, J. Appl. Phys. 70, 6456 (1991).
• [4] W. F. Li, T. Ohkubo, K. Hono, M. Sagawa, J. Magn. Magn. Mater. 321, 1100 (2009).
• [5] T. S. Jang, Trends in Metals & Mat. Eng. (Korean) 23 (2), 24 (2010).
• [6] K. Hirota, H. Nakamura, T. Minowa, M. Honshima, IEEE Trans. Magn. 41, 2909 (2006).
• [7] D. S. Li, M. Nishimoto, S. Suzuki, K. Nishiyama, M. Itoh, K. Machida, 2009 IOP Conf. Ser.: Mater. Sci. Eng. 1, 012020 (2009).
• [8] M. Komuro, Y. Satsu, H. Suzuki, IEEE Trans. Magn. 46, 3831 (2010).
• [9] Y. Takata, K. Fukumoto, Y. Kaneko, A. Manabe, N. Miyamoto, S. Imada, S. Suga, J. Jpn. Soc. Powder Metallurgy 57 (12), 789 (2010).
• [10] M. W. Lee, T. S. Jang, J. Koran Powder Metall. Inst. (Korean) 23 (6), 432 (2016).
• [11] K.H.J. Buschow, Handbook of Magnetic Materials 10, 512 (1997).
• [12] M. W. Lee, K. H. Bae, S. R. Lee, H. J. Kim, T. S. Jang, Arch. Metall. Mater. 62 2B, 1263 (2017).
• [13] Junjie Ni, Tianyu Ma, Mi Yan, J. Magn. Magn. Mater. 323, 2549 (2011).
• [14] K. H. Bae, S. R. Lee, H. J. Kim, M. W. Lee, T. S. Jang, J. Appl. Phys. 118, 203902 (2015).
• [15] W. F. Li, T. Ohkubo, K. Hono, Acta Materialia 57, 1337 (2009).
• [16] W. F. Li, H. Seperi-Amin, T. Ohkubo, N. Hase, K. Hono, Acta Materialia 59, 3061 (2011).
• [17] M. Sagawa, Proc. 21st Workshop on Rare-Earth Permanent Magnets and their Applications, 183 (2010).

Uwagi

EN

1. This work is supported by the Sun Moon University Research Grant in 2018.

PL

2. Opracowanie rekordu w ramach umowy 509/P-DUN/2018 ze środków MNiSW przeznaczonych na działalność upowszechniającą naukę (2019).