Hydrogen Permeation Properties of Nb-Based Two-Phase Compounds

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Nb-NiTi and Nb-CoTi eutectic alloys were directionally solidified in an optical floating zone furnace. Rod-type eutectic structures with Nb rods aligned parallel to the growth direction are obtained for Nb-41Ni-40Ti grown at relatively slow growth rates below 1.0mm/h, while lamellar-type eutectic structures are obtained for Nb-35Co-34Ti grown at the same condition. The hydrogen permeability for the Nb-41Ni-40Ti DS alloy with Nb rods perpendicular to the membrane surface is 2.60×10-8mol H2 m-1 Pa-1/2 at 673K, which is about 2.5 times higher than that of as-cast sample. No hydrogen embrittlement is observed between 573 and 673K, indicating that the Nb-NiTi rod-type eutectic structure effectively suppresses the hydrogen embrittlement of Nb during hydrogen permeation.

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Periodical:

Materials Science Forum (Volumes 561-565)

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Edited by:

Young Won Chang, Nack J. Kim and Chong Soo Lee

Pages:

467-470

Citation:

Y. Yamaguchi et al., "Hydrogen Permeation Properties of Nb-Based Two-Phase Compounds", Materials Science Forum, Vols. 561-565, pp. 467-470, 2007

Online since:

October 2007

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$38.00

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