Journal of Magnetics

The Korean Magnetics Society (한국자기학회)
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Effect of Die-upset Process on Magnetic Properties and Deformation Behavior of Nanostructured Nd-Fe-B Magnets

  • Zhao, R. (Division of Functional Materials, Central Iron & Steel Research Institute) ;
  • Zhang, W.C. (Division of Functional Materials, Central Iron & Steel Research Institute) ;
  • Li, J.J. (Division of Functional Materials, Central Iron & Steel Research Institute) ;
  • Wang, H.J. (Division of Functional Materials, Central Iron & Steel Research Institute) ;
  • Zhu, M.G. (Division of Functional Materials, Central Iron & Steel Research Institute) ;
  • Li, W. (Division of Functional Materials, Central Iron & Steel Research Institute)
  • Received : 2011.06.24
  • Accepted : 2011.07.27
  • Published : 2011.09.30
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Abstract

Nd-Fe-B high performance magnets were prepared by die-upset forging. The effects of the deformation parameters on magnetic properties and flow stress were studied. Deformation temperatures in the range of $600{\sim}900^{\circ}C$ enable to achieve an effective anisotropy and temperature $800^{\circ}C$ proves to be suitable for deformation of Nd-Fe-B magnets. The amount of c-axis alignment along the press direction seems to depend on the amount of deformation and a saturation behavior is shown at deformation ratio of 75%. Magnetic properties are also related to strain rate, and maximum energy product is attained at an optimum strain rate of ${\varphi}=1{\times}10^{-2}s^{-1}$. By analyzing the relationship of stress and strain at different deformation temperature during die-upset forging process, deformation behavior of Nd-Fe-B magnets was studied and parameters for describing plastic deformation were obtained. Nd-rich boundary liquid phase, which is additionally decreasing the flow stress during deformation, is supposed to play the role of diffusion path and enhance the diffusion rate.

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References

  1. T. Saito, M. Fujita, T. Kuji, K. Fukuoka, and Y. Syono, J. Appl. Phys. 83, 6390 (1998). https://doi.org/10.1063/1.367522
  2. P. P. Yi, D. Lee, and A. R. Yan, J. Magn. Magn. Mater. 322, 3019 (2010). https://doi.org/10.1016/j.jmmm.2010.05.022
  3. L. Wojciech and H. A. Davies, J. Alloys Compd. 491, 694 (2010). https://doi.org/10.1016/j.jallcom.2009.11.047
  4. L. Li and C. D. Graham, IEEE Trans. Magn. 28, 2130 (1992). https://doi.org/10.1109/20.179419
  5. A. Kirchner, J. Thomas, O. Gutfleisch, D. Hinz, K.-H. Müller, and L. Schultz, J. Alloys Compd. 365, 286 (2004). https://doi.org/10.1016/S0925-8388(03)00661-3
  6. A. H. Li, W. Li, B. Lai, H. J. Wang, M. G. Zhu, and W. Pan, J. Appl. Phys. 107, 09A725 (2010). https://doi.org/10.1063/1.3339817
  7. D. N. Brown, B. Smith, B. M. Ma, and P. Campbell, IEEE Trans. Magn. 40, 2895 (2004). https://doi.org/10.1109/TMAG.2004.832240
  8. W. Grünberger, D. Hinz, A. Kirchner, K.-H. Müller, and L. Schultz, J. Alloys Compd. 257, 293 (1997). https://doi.org/10.1016/S0925-8388(97)00026-1
  9. H. T. Kim, Y. B. Kim, G. A. Kapustin, W. Y. Jeon, and H. S. Kim, J. Magnetics 7, 138 (2002). https://doi.org/10.4283/JMAG.2002.7.4.138
  10. C. D. Fuerst and E. G. Brewer, J. Appl. Phys. 73, 5751 (1993). https://doi.org/10.1063/1.353563
  11. H. W. Kwon and J. H. Yu, IEEE Trans. Magn. 45, 4435 (2009). https://doi.org/10.1109/TMAG.2009.2023871
  12. Y. Yoshida, Y. Kasai, T. Watanabe, and S. Shibata, J. Appl. Phys. 69, 5841 (1991). https://doi.org/10.1063/1.347844

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