Abstract
Pressure-composition isotherms (PCTs) for amorphous and icosahedral (i) quasicrystal powders produced by mechanical alloying of Ti45Zr38Ni17 powder mixtures were measured at temperatures of 473 K and 523K at low-hydrogen pressures, lower than 0.1 MPa. Sloping plateau-like features on PCTs were observed at equilibrium hydrogen pressures lower than 1 kPa, below an H/M (hydrogen to metal atom ratio) ≈ 1.2 and ≈ 1 for the amorphous and i-phase powders respectively. The plateau-like region for the i-phase powder was steeper and narrower than that for the amorphous powder, implying some small differences between the local structures of the i-phase and the amorphous phase. After the PCT measurements, an increase in the nearest-neighbor atom spacing and an expansion of the quasilattice were observed for the amorphous and i-phase powders respectively. Impurities from some unsynthesized elemental material and a Ti2Ni type phase were also present. These also absorbed hydrogen, shown by an expansion of their crystal lattices. However, no crystal hydride formation was observed in any of the powders.
Original language | English |
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Pages (from-to) | 2165-2168 |
Number of pages | 4 |
Journal | Materials Transactions |
Volume | 43 |
Issue number | 8 |
DOIs | |
Publication status | Published - 2002 Aug |
Externally published | Yes |
Keywords
- Amorphous
- Hydrogen absorption
- Mechanical alloying
- Pressure-composition isotherm
- Quasicrystal
- TiNi phase
- Titanium-zirconium-nickel alloy
ASJC Scopus subject areas
- Materials Science(all)
- Condensed Matter Physics
- Mechanics of Materials
- Mechanical Engineering