Journal of Powder Materials (한국분말재료학회지)

The Korean Powder Metallurgy & Materials Institute (한국분말재료학회 (*구 분말야금학회))
권호 표지
DOI QR코드

DOI QR Code

Effect of Magnetic properties and Microstructure of Hydrogenation stage in HDDR process

HDDR 반응시 수소화 반응이 Nd-Fe-B계 분말의 미세조직과 자기적 특성에 미치는 영향

  • 이상협 (부산대학교 재료공학과) ;
  • 유지훈 (한국기계연구원 부설 재료연구소) ;
  • 김양도 (부산대학교 재료공학과)
  • Received : 2011.07.20
  • Accepted : 2011.09.18
  • Published : 2011.10.28
Download PDF
⟨ Previous Next ⟩

Abstract

The HDDR(hydrogenation-disproportionation-desorption-recombination) process can be used as an effective way of converting no coercivity Nd-Fe-B material, with a coarse $Nd_2Fe_{14}B$ grain structure to a highly coercive one with a fine grain. Careful control of the HDDR process can lead to an anisotropic $Nd_2Fe_{14}B$ without any post aligning process. In this study, the effect of hydrogen gas input at various temperature in range of $200{\sim}500^{\circ}C$ of hydrogenation stage (named Modified-solid HDDR, MS-HDDR) on the magnetic properties has been investigated. The powder from the modified-solid HDDR process exhibits Br of 11.7 kG and iHc of 10.7 kOe, which are superior to those of the powder prepared using the normal HDDR process.

Keywords

References

  1. L. Yang: Proceeding of the 19th International Workshop on HPMA and their Application, (2006) 1.
  2. Y. Honkura: Proceeding of the 18th International Workshop on HPMA and their Application, (2004) 559.
  3. Y. Honkura: Proceeding of the 19th International Workshop on HPMA and their Application, (2006) 231.
  4. Y. Kawashita, N. Waki, T. Tayu, T. Sugiyama, H. Ono, H. Koyama, H. Kanno and T. Uchida: J. of Magnetism and Magnetic Materials, 269 (2004) 293. https://doi.org/10.1016/S0304-8853(03)00595-X
  5. P. L'Hereter, P. Chadouet, R. Madar, A. Rouault, J. Senateur and R. Fruchatr: C. R. Acad. Sci., 29911 (13) (1984) 849.
  6. I. R. Harris, C. Noble and T. Bailey: J. Less-Common Met., 106 (1985) L1. https://doi.org/10.1016/0022-5088(85)90380-7
  7. J. M. Cadogan and J. M. D. Coey: Appl. Phys. Lett., 48(6) (1986) 442. https://doi.org/10.1063/1.96525
  8. H. Oesterreicher: Proc. 4th Int. Symp. on Magnetic Anisotropy and Coercivity in Rare-Earth Transition Metal Alloys, Dayton, (1985) 705.
  9. A. J. Williams, O. Gutfleisch and I. R. Harris: J. Alloys and Compounds, 232 (1996) L22. https://doi.org/10.1016/0925-8388(95)02101-9
  10. J. H. Yu, S. H. Lee and D. H. Kim: J. of Korean Powder Metallurgy Institute Vol. 16, No. 4, (2009) 286.
  11. I. R. Harris and P. J. McGuiness: J. of the Less-Common Metals, 172 (1991) 1273. https://doi.org/10.1016/S0022-5088(06)80037-8
  12. O. Gutfleisch, M. Verdier and I. R. Harris: J. of Alloys and Compounds, 196(1993) L19 https://doi.org/10.1016/0925-8388(93)90560-A
  13. A. Bollero, O. Gutfleisch and M. Kubis: J. of the Acta mater., 48 (2000) 4929. https://doi.org/10.1016/S1359-6454(00)00270-6
  14. S. Sugimoto, H. Nakamura, K. Kato, D. Book, T. Kagotani, M. Okada and M. Homma: J. Alloys and Compounds 293-295 (1999) 862-867. https://doi.org/10.1016/S0925-8388(99)00376-X

Cited by

  1. The Influence of Dehydrogenation Speed on the Microstructure and Magnetic Properties of Nd-Fe-B Magnets Prepared by HDDR Process vol.19, pp.1, 2014, https://doi.org/10.4283/JMAG.2014.19.1.049