R. M. Belyakova, E. D. Kurbanova, N. I. Sidorov, V. A. Polukhin.
ABSTRACT
Membrane evolution of ultrapure hydrogen is now considered one of the most effective technologies largely due to the alternative replacement of expensive Pd-Ag membrane alloys with cheaper ones based on bcc metals of the VB group (V, Nb, Ta, etc.) with an amorphous, nanocrystalline structure with a permeability exceeding that of palladium alloys with an fcc structure. However, hydrogen-selective membrane alloys of bcc metals Co, V, Cr, Ta, Nb, although they demonstrate very high hydrogen permeability, are subject to brittle destruction due to excessive absorption of hydrogen. A comparative analysis of the kinetics of hydrogen in titanium-doped membrane binary alloys Nb-Ni and V-Ni, according to such criteria as strength characteristics, thermal stability and resistance to hydrogen embrittlement. The dissolution of Ni and Ti in the niobium and vanadium phases increases the critical temperature of β-hydride formation from 200 to 400°C. In addition, Ni-Ti and NiTi2 compounds stabilize the matrix structure of membrane alloys and prevent hydride formation.
KEYWORDS
membrane alloys, alloying, niobium-titanium-nickel, vanadium-titanium-nickel, matrix microstructure, hydrogenation, absorption, diffusion, hydrogen permeability, phase formation, Me-H hydrides, embrittlement, duplex structure
DOI: 10.31857/S0235010622020025