TY - JOUR
T1 - Lattice defects in V-Ti BCC alloys before and after hydrogenation
AU - Matsuda, Junko
AU - Akiba, Etsuo
N1 - Funding Information:
The author(s) gratefully acknowledge the support of the International Institute for Carbon Neutral Energy Research ( WPI-I2CNER ), sponsored by the Japanese Ministry of Education, Culture, Sports, Science and Technology (MEXT) . This work was partly supported by The New Energy and Industrial Technology Development Organization (NEDO) under Advanced Research on Hydrogen Storage Materials (HYDRO-STAR) .
PY - 2013
Y1 - 2013
N2 - Microstructures of V-Ti BCC alloys before and after hydrogenation/ dehydrogenation are investigated using transmission electron microscopy. Strain contrast with spacing smaller than 20 nm is observed both in the as-cast alloys and hydrogenated alloys. Twin boundaries and stacking faults with spacing of 5-20 nm are introduced into the V-Ti BCC alloys after hydrogenation. These are parallel to {1-1 1} planes of FCC hydrides. The twin boundaries and stacking faults are formed due to the accommodation of shear stress during hydrogenation accompanied by large anisotropic expansion along the c-axis direction in V-Ti BCC alloys. Density of twin boundaries is high in the alloys with small contents of V, which have a small effective hydrogen capacity at ambient condition. Dependence of microstructure evolution in the V-Ti alloys during hydrogenation on the V/Ti ratio is also discussed with the thermodynamic stabilities from measurements of Pressure-Composition isotherms and mechanical properties.
AB - Microstructures of V-Ti BCC alloys before and after hydrogenation/ dehydrogenation are investigated using transmission electron microscopy. Strain contrast with spacing smaller than 20 nm is observed both in the as-cast alloys and hydrogenated alloys. Twin boundaries and stacking faults with spacing of 5-20 nm are introduced into the V-Ti BCC alloys after hydrogenation. These are parallel to {1-1 1} planes of FCC hydrides. The twin boundaries and stacking faults are formed due to the accommodation of shear stress during hydrogenation accompanied by large anisotropic expansion along the c-axis direction in V-Ti BCC alloys. Density of twin boundaries is high in the alloys with small contents of V, which have a small effective hydrogen capacity at ambient condition. Dependence of microstructure evolution in the V-Ti alloys during hydrogenation on the V/Ti ratio is also discussed with the thermodynamic stabilities from measurements of Pressure-Composition isotherms and mechanical properties.
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U2 - 10.1016/j.jallcom.2013.07.073
DO - 10.1016/j.jallcom.2013.07.073
M3 - Article
AN - SCOPUS:84881180517
VL - 581
SP - 369
EP - 372
JO - Journal of Alloys and Compounds
JF - Journal of Alloys and Compounds
SN - 0925-8388
ER -