We examined the hydrogen permeation of melt-spun Ni-Nb-Zr amorphous alloys. The interatomic spacing in the (Ni0.6Nb0.4) 100-xZrx (x = 0-50) amorphous structure increased with increasing Zr content. The permeability of the alloys is strongly dependent on alloy compositions. The maximum hydrogen permeability was 1.59 x 10-8 (mol/m sPa1/2) at 673 K for the (Ni0.6Nb 50Zr50 amorphous alloy. It is noticed that the permeability is as high as that of pure Pd metal at 673 K. The hydrogen permeability of the amorphous alloy is larger than that of pure Pd metal at the temperature below 673 K. Moreover, it is important to study the relationship between hydrogen permeation and atomic structure of amorphous alloys to understand the hydrogen permeation mechanism through amorphous alloys. We investigated the amorphous structures of these alloys by the radial distribution function (RDF) analysis. As a result, it was found that the number of the Zr-Zr pair which has larger interatomic distance than any other pairs such as Ni-Ni, Nb-Nb, Ni-Nb, Ni-Zr and Nb-Zr increased with increasing Zr content. Therefore, hydrogen atoms can permeate more easily through the Ni-Nb-Zr amorphous membrane with higher Zr content in the composition range of Ni-Nb-Zr amorphous alloys prepared in this work. These permeation characteristics and structural features indicate the possibility of future practical use of the melt-spun amorphous alloys as a hydrogen permeable membrane.
|ジャーナル||Journal of Metastable and Nanocrystalline Materials|
|出版ステータス||Published - 2005|
ASJC Scopus subject areas
- Materials Science (miscellaneous)
- Materials Science(all)
- Condensed Matter Physics
- Physical and Theoretical Chemistry