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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

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