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Direct production of the Ti-Zr-Ni-Cu icosahedral phase for hydrogen-storage applications by rapid quenching from the melt
Published online by Cambridge University Press: 01 February 2011
Abstract
Our study focused on the formation of Ti40Zr40Ni20 and Ti45Zr35Ni17Cu3 icosahedral (i-phase) quasicrystals directly from the melt and their subsequent characterization and high-pressure hydrogenation. The samples were produced in an inert-gas melt-spinning device from a series of arc-melted precursors. By varying the wheel speeds we were able to produce a range of crystallographic structures, from amorphous, through quasicrystalline, to crystalline. The ribbon thickness showed the expected reduction with wheel speed, from 120 microns to 30 microns, while the Ms exhibited a surprisingly modest change with wheel speed. The XRD analysis showed that depending on the cooling rate it was possible to freeze the icosahedral phase directly from the melt, without any subsequent heat-treatment. Using the same procedure to test the range of formation wheel speeds for a comparable system we also produced samples containing up to 3 atomic % copper. Using transmission electron microscopy we have confirmed that the ribbons contain nanosized particles of Ti40Zr40Ni20 icosahedral phase imbedded in an amorphous matrix with the same composition. The average particle size of the i-phase was approximately 20 nm. The 5-fold symmetry was confirmed by selected-area electron diffraction and high-resolution TEM having the crystallite oriented close to the symmetry axis. Both our X-ray diffraction measurements and the TEM observations have provided direct evidence for the quasicrystalline ordering of Ti40Zr40Ni20 by rapid quenching from the melt. To test the hydrogen-absorption properties of the icosahedral phase we crushed ribbons into finer particles to provide fresh, new surfaces to aid hydrogen dissociation at the metal surface. The uptake of hydrogen was found to be critically dependent on the surface state of the Ni–Ti–Zr ribbons; even modest exposure to the atmosphere produced a protective layer of oxide on the surface that practically prevented any hydrogen being taken up by the icosahedral phase. The concentration of hydrogen in the i-phase was determined from the shift in the XRD peaks. The calculated expansion of aq was 6% and the corresponding [H]/[M] value was 1.5.
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- Copyright © Materials Research Society 2008
References
1.
Viano, A.M., Majzoub, E.H., Stroud, R.M., Kramer, M.J., Misture, S.T., Gibbons, P.C., Kelton, K.F., Phil. Mag. A 78 (1998) 131–141
Google Scholar
3.
Hydrogenation of titanium-based quasicrystals, Viano, A. M., Stroud, R. M., Gibbons, P. C., McDowell, A. F., Conradi, M. S., and Kelton, K. F., Phys. Rev. B
51 (1995) 12026–12029
Google Scholar
4.Icosahedral and amorphous phases in melt-spun Ti-Zr-Ni-Cu alloys, Wang, L., Inoue, A., Materials Transactions
42 (12) (2001) 2637–2640
Google Scholar
5.
Formation and mechanical properties of Ti-Zr-Ni-Cu amorphous alloy containing icosahedral nanoscale quasicrystalline phase, Wang, L., Ma, L., Innoue, A., Materials Transactions
43 (9) (2002) 2346–2349
Google Scholar
6.Formations of amorphous and quasicrystal phases in Ti-Zr-Ni-Cu alloys, Wang, L., Ma, L., Ma, C., Inoue, A., Journal of Alloys and Compounds
361 (1-2) (2006) 234–240
Google Scholar
7.
Hydrogen absorption in Ti–Zr–Ni–Cu amorphous alloy, Guo, X.Q., Louzguine, D.V., Yamaura, S., Ma, L.Q., Sun, W., Hasegawa, M., Inoue, A., Mat. Sci. and Eng.
A338 (2002) 97–100
10.1016/S0921-5093(02)00091-6Google Scholar
8.
Indexing of icosahedral quasiperiodic crystals, Cahn, J.W., Shechman, D., Gratias, D., Journal of Materials Research (1986), Vol. 1, 13–26
10.1557/JMR.1986.0013Google Scholar