Thesis - Oztek_Muzaffer_T_200508_MA

LIST OF FIGURES
Figure 1. Pressure-composition diagram for LaNi 5 [17]..................................................... 7
Figure 2. Energy diagram for metastable phase formation by mechanical alloying. ....... 15
Figure 3. Cubic space lattice of an ideal crystalline (left) solid and the unit cell (right)
[50]............................................................................................................................ 18
Figure 4. CaCu5-type P6/mmm structure of LaNi 5 [51]. Gray spheres indicate La atoms.
................................................................................................................................... 19
Figure 5. The high energy Spex 8000M Mixer/Mill (left) and the Fritsch Planetary Mill
(right). ....................................................................................................................... 25
Figure 6. Schematic representation of the DSC setup. P denotes pressure transducer..... 26
Figure 7. The U-tube reactor............................................................................................. 30
Figure 8. Coating thickness dependence on coating duration........................................... 33
Figure 9: Thermogram for initial hydriding of Mg 2 Ni. .................................................... 37
Figure 10: Composition and pressure plots for initial hydriding of Mg 2 Ni...................... 38
Figure 11: Thermogram for dehydriding of Mg 2 Ni.......................................................... 39
Figure 12: Percent hydrogen desorbed for dehydriding of Mg 2 Ni. .................................. 40
Figure 13: Thermogram for initial hydriding of VTiNi.................................................... 41
Figure 14: Composition and pressure curves for the initial hydriding of VTiNi.............. 42
Figure 15: Thermogram for dehydriding of VTiNi. ......................................................... 43
Figure 16: Percent hydrogen desorbed for dehydriding of VTiNi.................................... 44
Figure 17: Thermogram of ball milled and thermally activated LaNi 5 . ........................... 47
Figure 18: Composition curve of ball milled and thermally activated LaNi 5 ................... 47
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