The disappearance of hysteresis for the hydride phase transition in palladium-nickel alloys

Journal Article · Sun Sep 01 04:00:00 EDT 1991 · Scripta Metallurgica; (United States)

DOI:https://doi.org/10.1016/0956-716X(91)90295-C· OSTI ID:5502561

Noh, H; Flanagan, T B; Gavra, Z ^[1]; Johnson, J R; Reilly, J J ^[2]

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1. Vermont Univ., Burlington, VT (United States). Dept. of Chemistry
2. Brookhaven National Lab., Upton, NY (United States). Applied Science Dept.

Hysteresis generally accompanies first order phase transitions which occur in the solid state and for this reason it is important. Its study has, however, been somewhat neglected. It is almost always present in the formation and decomposition of metal hydrides. The vanishing of hysteresis for such a system is noteworthy and this research is concerned with the disappearance. This paper reports that Pd-Ni alloys are reported to form a continuous series of fcc solid solutions over their entire concentration range. The present research concerns hydrogen absorption by several of these, initially homogeneous, Pd-rich alloys before and after they are subjected to a series of hydride formation and decomposition (cycling) phase transitions without intermediate annealing treatments. Pd-Ni alloys are unusual with regard to their hydrogen solubility behavior because the plateau pressures for hybrid formation/decomposition are greater than for pure Pd and the extents of these plateau regions do not markedly decrease with increase of % substituted metal, i.e. Ni. (The latter aspect of their behavior is more unusual than for former.) The increase in plateau pressure seems to be a characteristic of Pd substitutional alloys which have contracted volumes as compared to Pd itself.

• OSTI ID: 5502561
• Journal Information: Scripta Metallurgica; (United States), Journal Name: Scripta Metallurgica; (United States) Vol. 25:9; ISSN 0036-9748; ISSN SCRMB
• Country of Publication: United States
• Language: English

Related Subjects

08 HYDROGEN
080201 -- Hydrogen-- Chemisorption Storage
080800 -- Hydrogen-- Properties & Composition
36 MATERIALS SCIENCE
360102* -- Metals & Alloys-- Structure & Phase Studies
ABSORPTION SPECTRA
ALLOYS
CHEMICAL REACTIONS
CHEMISORPTION
CRYSTAL LATTICES
CRYSTAL STRUCTURE
CUBIC LATTICES
DISPERSIONS
ELEMENTS
FCC LATTICES
HYDRIDES
HYDROGEN
HYDROGEN COMPOUNDS
HYDROGEN STORAGE
HYSTERESIS
MIXTURES
NICKEL ALLOYS
NONMETALS
PALLADIUM ALLOYS
PHASE TRANSFORMATIONS
PLATINUM METAL ALLOYS
RESEARCH PROGRAMS
SEPARATION PROCESSES
SOLID SOLUTIONS
SOLUBILITY
SOLUTIONS
SORPTION
SPECTRA
STORAGE