TY - JOUR
T1 - Hydrogen permeation in rapidly quenched amorphous and crystallized Nb 20Ti40Ni40 alloy ribbons
AU - Ishikawa, Kazuhiro
AU - Seki, Yuta
AU - Kita, Koichi
AU - Matsuda, Mitsuhiro
AU - Nishida, Minoru
AU - Aoki, Kiyoshi
N1 - Funding Information:
This work was financially supported in part by a ‘‘Grant-in-Aid’’ for Scientific Research from the Ministry of Education, Culture, Sports, Science and Technology (MEXT) of Japan . The authors thank Mr. Morita of Mitsubishi Materials Corporation for preparation of the rapidly quenched alloy membrane, and Mr. Tokunaga, undergraduate student of the Kitami Institute of Technology for performing the PCT measurements.
PY - 2011/1
Y1 - 2011/1
N2 - Formation of an amorphous (a-) Nb20Ti40Ni 40 alloy by rapid quenching and its crystallization behavior were investigated by X-ray diffraction, differential scanning calorimetry and scanning electron microscopy. The B2-TiNi phase was firstly crystallized and the remaining amorphous (a-) phase subsequently decomposed into the bcc-(Nb, Ti) + B2-TiNi phases. The crystallized (c-) Nb20Ti40Ni 40 samples obtained by annealing above 1173 K were ductile and insusceptible to hydrogen embrittlement between 598 and 673 K. Hydrogen permeability at 673 K (Φ673K) for the a- and c-Nb20Ti 40Ni40 alloys were 8.1 × 10-9 and (3.0-4.8) × 10-9 mol H2/m/s/Pa0.5, respectively. Φ673K increased with the increase in the diameter of the bcc-(Nb, Ti) phase, although this led to poor resistance to hydrogen embrittlement. The lower hydrogen permeability of the c-Nb20Ti 40Ni40 alloy was due to its lower hydrogen diffusivity. The present work demonstrated that rapid quenching and subsequent annealing are useful to prepare thermally stable Nb-TiNi hydrogen permeation alloy membranes.
AB - Formation of an amorphous (a-) Nb20Ti40Ni 40 alloy by rapid quenching and its crystallization behavior were investigated by X-ray diffraction, differential scanning calorimetry and scanning electron microscopy. The B2-TiNi phase was firstly crystallized and the remaining amorphous (a-) phase subsequently decomposed into the bcc-(Nb, Ti) + B2-TiNi phases. The crystallized (c-) Nb20Ti40Ni 40 samples obtained by annealing above 1173 K were ductile and insusceptible to hydrogen embrittlement between 598 and 673 K. Hydrogen permeability at 673 K (Φ673K) for the a- and c-Nb20Ti 40Ni40 alloys were 8.1 × 10-9 and (3.0-4.8) × 10-9 mol H2/m/s/Pa0.5, respectively. Φ673K increased with the increase in the diameter of the bcc-(Nb, Ti) phase, although this led to poor resistance to hydrogen embrittlement. The lower hydrogen permeability of the c-Nb20Ti 40Ni40 alloy was due to its lower hydrogen diffusivity. The present work demonstrated that rapid quenching and subsequent annealing are useful to prepare thermally stable Nb-TiNi hydrogen permeation alloy membranes.
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U2 - 10.1016/j.ijhydene.2010.10.095
DO - 10.1016/j.ijhydene.2010.10.095
M3 - Article
AN - SCOPUS:79551491328
SN - 0360-3199
VL - 36
SP - 1784
EP - 1792
JO - International Journal of Hydrogen Energy
JF - International Journal of Hydrogen Energy
IS - 2
ER -
