SPECIFIC STRUCTURE OF EFFECTIVE MEMBRANE ALLOYS BASED ON NIOBIUM, VANADIUM AND ZIRCONIUM

Abstract

With unique mechanical and functional properties, amorphous, nanocrystalline and matrix duplex microstructure membrane alloys based on group V elements actively contribute to the development of hydrogen energy. There are still not completely resolved problems for these new alloys - their low thermal stability, insufficient mechanical strength (plasticity, hardness), and intermetallic and hydride embrittlement. For effective use, alloys with a triple composition are being developed – which, in addition to the elements of group V, also include nickel and titanium as alloying metals. Not only amorphous and nanocrystalline alloys are obtained that are applicable in electronics and power engineering, as well as membrane alloys with a duplex matrix structure that combines amorphous, nano- and quasicrystalline dendritic-hardening phases strengthening the amorphous matrix. In specialized membrane ternary alloys, NiTi and NiTi2 compounds are formed, which stabilize and protect nano- and crystalline membranes from brittle destruction. It has been found that the intense formation of hydrides in these alternative membrane alloys is as undesirable as for palladium-based compounds. The alloys under consideration actually make it possible to obtain high-purity gaseous hydrogen using new compositions instead of expensive membranes based on Pd-Au/Ag/Cu alloys.

Keywords

• amorphous and nanocrystalline alloys
• nickel
• titanium
• zirconium
• niobium
• structurization
• membrane gas separation
• hydrogen purification
• solubility
• hydrogen permeability
• accumulation
• thermal stability
• fragility
• crystallization
• modeling
• diffusion
• nanophases
• me-h hydrides
• embrittlement
• duplex matrix microstructure