Skip to main content
Log in

HDDR Process and Hydrogen-Absorption Properties of Didymium–Aluminum–Iron–Boron (Dd12.3Al1.2Fe79.4B6) Alloy

  • Published:
Materials Science Aims and scope

Abstract

We investigate the interaction of hydrogen with the alloy of the Dd–Al–Fe–B system containing (in wt. %) 28.6% Dd, up to 0.5% Al, 1.1% B, and the rest Fe. At an initial hydrogen pressure of 1.0 MPa, hydride with a hydrogen content of 0.5 wt. % is formed. Hydrogen adsorption is accompanied by an increase in the lattice constants (a grows by 1.4% and c does by 1.1%) under a total volume increase of 4.1%. According to the kinetics of hydrogen adsorption, the duration of a full saturation by hydrogen is 3–5 h at an initial gas pressure of 0.1–0.2 MPa. Under heating in the hydrogen medium, the alloy disproportionates at a temperature of 1003 K. X-ray diffraction data indicate that the ferromagnetic phase disproportionates into didymium hydride DdH x [a = 0.5443(2) nm, α-Fe (a = 0.2865(1) nm) and a = 0.5112(8) nm, c = 0.423(2) nm] and iron boride Fe2B. Heating of the products of disproportionation in vacuum to a temperature of 1123 K results in the recombination of the initial ferromagnetic phase.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

References

  1. I. R. Harris, “The potential of hydrogen in permanent magnet production,” J. Less-Common Met., 131, 245–262 (1987).

    Google Scholar 

  2. I. R. Harris, “The use of hydrogen in the production of Nd - Fe - Btype magnets and in the assessment of Nd - Fe - Btype alloys and permanent magnets,” in: Proc. 12th Int. Workshop on Rare Earth Magnets and Their Applications, Canberra, Australia (1992), p. 347.

  3. T. Takeshita and R. Nakayama, “Magnetic properties and microstructures of the Nd - Fe - B magnet powder produced by hydrogen treatment,” in: Proc. 12th Int. Workshop on Rare Earth Magnets and Their Applications, Canberra, Australia (1992), p. 67.

  4. H. P. Brekharya, E. A. Vasil'eva, V. V. Nemoshkalenko, et al., “Influence of the conditions of manufacture of permanent magnets of the didymium-iron-boron system on their structure and properties,” Metallofizika Noveishie Tekhnologii, 19, No. 10, 63–68 (1997).

    Google Scholar 

  5. H. P. Brekharya, E. A. Vasyl'eva, and S. V. Ustynova, Formation of the structure and properties of permanent magnets Fe-Dd-B depending on the temperature of their sintering,” Visn. Zap. Derzh. Univ. Fiz.Mat. Nauki, No. 2, 156–161 (1998).

    Google Scholar 

  6. H. P. Brekharya, E. A. Vasil'eva, V. V. Nemoshkalenko, et al., “Influence of the heating of permanent magnets of the didymium- iron-boron system on their structure and properties,” Metallofizika Noveishie Tekhnologii, 20, No. 7, 38–44 (1998).

    Google Scholar 

  7. Yu. Putilov, M. Morozova, Yu. Shestak, S. Ustinova, and N. Yanchik, “Improvement of manufacturing of highenergy permanent magnets didymiumironboron,” in: Proc. 16th Int. Workshop on Rare Earth Magnets and Their Applications (Sendai, Japan, September 2000), Sendai, Japan (2000), p. 215.

  8. I. I. Bulyk, V. A. Yartys, R. V. Denys, Ya. M. Kalychak, and I. R. Harris, “Hydrides of the RNiIn (R = La, Ce, Nd) intermetallic compounds: Crystallographic characterisation and thermal stability,” in: Int. J. Hydrogen Energy, 284 (1999), pp. 256–261.

    Google Scholar 

  9. D. Book and I. R. Harris, “HDDR studies on Nd16 Fe76 B8 and Nd11.8 Fe82.3 B5.9,” in: Proc. 13th Int. Workshop on Rare Earth Magnets and Their Applications (Birmingham, UK, September 11-14, 1994), Birmingham, UK (1994), p. 205.

  10. M. M. Antonova, Properties of Metal Hydrides. Handbook [in Russian], Naukova Dumka, Kiev (1975).

    Google Scholar 

  11. F. D. Saccone, F. H. Sanchez, C. Rodriguez Torres, B. Gebel, and O. Gutfleisch, “Observation by Mössbauer effect spectroscopy of the formation of tFe3 B in solid and conventional hydrogen disproportionated Nd - Fe - B alloy,” in: Proc. 16th Int. Workshop on Rare Earth Magnets and Their Applications (Sendai, Japan, September 2000), Sendai, Japan (2000), p. 821.

Download references

Author information

Authors and Affiliations

Authors

Rights and permissions

Reprints and permissions

About this article

Cite this article

Bulyk, I.I., Denys, R.V., Panasyuk, V.V. et al. HDDR Process and Hydrogen-Absorption Properties of Didymium–Aluminum–Iron–Boron (Dd12.3Al1.2Fe79.4B6) Alloy. Materials Science 37, 544–550 (2001). https://doi.org/10.1023/A:1013230718369

Download citation

  • Issue Date:

  • DOI: https://doi.org/10.1023/A:1013230718369

Keywords

Navigation