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Structures and magnetic properties of Nd–Fe–B bulk nanocomposite magnets produced by the spark plasma sintering method

Published online by Cambridge University Press:  03 March 2011

Tetsuji Saito*
Affiliation:
Department of Mechanical Science and Engineering, Chiba Institute of Technology, Narashino, Chiba 275-0016, Japan
Tomonari Takeuchi
Affiliation:
National Institute of Advanced Industrial Science and Technology (AIST),Ikeda, Osaka 563-8577, Japan
Hiroyuki Kageyama
Affiliation:
National Institute of Advanced Industrial Science and Technology (AIST),Ikeda, Osaka 563-8577, Japan
*
a) Address all correspondence to this author. e-mail: [email protected]
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Abstract

We studied the effects of the sintering temperature and applied pressure on Nd–Fe–B bulk nanocomposite magnets produced by the spark plasma sintering (SPS) method. Amorphous Nd4Fe77.5B18.5 melt-spun ribbons were successfully consolidated into bulk form by the SPS method. When sintered at 873 K under applied pressures between 30 and 70 MPa, the bulk materials consisted of nanocomposite materials with a soft magnetic Fe3B phase and hard magnetic Nd2Fe14B phase. The density and magnetic properties of the bulk materials sintered at 873 K were strongly dependent on the applied pressure during sintering. Bulk Nd4Fe77.5B18.5 nanocomposite magnets sintered at 873 K under an applied pressure of 70 MPa showed a high remanence of 9.3 kG with a high coercivity of 2.5 kOe.

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Articles
Copyright
Copyright © Materials Research Society 2004

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References

REFERENCES

1.Coehoorn, R., de Mooij, D.B., Duchateau, J.P. andBuschow, K.H.J.: Novel permanent magnetic materials made by rapid quenching. J. Phys. 49 C8–669 (1988).Google Scholar
2.Skomski, R. andCoey, J.M.D.: Giant energy product in nanostructured two-phase magnets. Phys. Rev. B 48, 15812 (1993).CrossRefGoogle ScholarPubMed
3.Jakubowicz, J., Szlaferek, A. andJurczyk, M.: Magnetic properties of nanostructured Nd2(Fe,Co, Cr)14B/α-Fe. J. Alloys Compd 283, 307 (1999).CrossRefGoogle Scholar
4.Cline, C.F. andHopper, R.W.: Explosive fabrication of rapidly quenched materials. Scripta Metall. 11, 1137 (1977).CrossRefGoogle Scholar
5.Harada, T., Kuji, T., Fukuoka, K. andSyono, Y.: Dynamic compaction of amorphous Nd15Fe77B8 alloy powders. J. Mater. Sci. Lett. 11, 1072 (1990).CrossRefGoogle Scholar
6.Shingu, P.H.: Metastablility of amorphous phases and its application to consolidation of rapidly quenched powders. Mater. Sci. Eng. 97, 137 (1988).CrossRefGoogle Scholar
7.Saito, T.: Production of bulk materials of an Nd4Fe77.5B18.5 alloy and their magnetic properties. IEEE Trans. Mag. 37, 2561 (2001).CrossRefGoogle Scholar
8.Tokita, M.: Trends in advanced SPS spark plasma sintering system and technology. J. Soc. Powder Technol. Jpn. 30, 790 (1993).CrossRefGoogle Scholar
9.Liu, Z.G., Umemoto, M., Hirosawa, S. andKanekiyo, H.: Spark plasma sintering of Nd–Fe–B magnetic alloy. J. Mater. Res. 14, 2540 (1999).CrossRefGoogle Scholar
10.Ono, H., Waki, N., Shimada, M., Sugiyama, T., Fujiki, A., Yamamoto, H. andTani, M.: Isotropic bulk exchange-spring magnets with 134 kJ/m3 prepared by spark plasma sintering method. IEEE Trans. Mag. 37, 2552 (2001).CrossRefGoogle Scholar
11.Saito, T., Takeuchi, T. andKageyama, H.: Production of bulk amorphous and nanocomposite materials of an Nd4Fe77.5B18.5 alloys by spark plasma sintering method. IEEE Trans. Mag. (in press)Google Scholar
12.Saito, T., Fujita, M., Kuji, T., Fukuoka, K. andSyono, Y.: The development of high performance Nd–Fe–Co–Ga–B die upset magnets. J. Appl. Phys. 83, 6390 (1998).CrossRefGoogle Scholar
13.Takeuchi, T., Kondoh, I., Tamari, N., Balakrishnan, N., Nomura, K., Kageyama, H. andTakeda, Y.: Improvement of mechanical strength of 8 mol% yttria-stabilized zirconia ceramics by spark-plasma sintering. J. Electrochem. Soc. 149 A455 (2002).CrossRefGoogle Scholar
14.Hinomura, T., Nasu, S., Kanekiyo, H., Uehara, M. andHirosawa, S.: Magnetic properties of Nd–Fe–B–Cr nanocomposite magnets. Mater. Trans. JIM 38, 1106 (1997).CrossRefGoogle Scholar
15.Bao-gen, S., Lin-yuan, Y., Jun-xain, Z., Feng, W., Tai-shan, N., Jian-gao, Z., Hui-qun, G. andWen-shan, Z.: Magnetic properties of amorphous (Fe1-xCox)77.5Nd4B18.5 alloys and the effects of heat treatment on its hard magnetic properties. J. Magn. Magn. Mater. 96, 335 (1991).CrossRefGoogle Scholar
16.Schneider, G., Henig, E.T., Petzow, G. andStadelmaier, H.H.: Phase relations in the system Fe–Nd–B. Z. Metallkunde 77, 775 (1986).Google Scholar
17.Sagawa, M., Fujimura, S., Togawa, N., Yamamoto, H. andMatsuura, Y.: New materials for permanent magnets on a base of Nd and Fe. J. Appl. Phys. 55, 2083 (1984).CrossRefGoogle Scholar
18.Coehoorn, R., de Mooij, D.B. andde Waard, C.: Melt-spun permanent magnet materials containing Fe3B as the main phase. J. Magn. Magn. Mater. 80, 101 (1989).CrossRefGoogle Scholar
19.Hirose, Y., Hasegawa, H. andSasaki, S. Microstructure of strip cast alloys for high performance NdFeB magnets, in Proceedings of the Fifteenth International Workshop on Rare-Earth Magnets and their Applications, edited by Schults, L. and Müller, K. H. (Werkstoff-Informationsgesellschaft mbH, Frankfurt, Germany, 1998), p. 77Google Scholar
20.Lee, R.W., Brewer, E.G. andSchaffel, N.A.Processing of neodymium-iron-boron melt-spun ribbons to fully dense magnets. IEEE Trans. Magn. MAG–21, 1958 (1985).Google Scholar