Thermodynamics of open two-phase systems with coherent interfaces

Journal Article · Mon Mar 27 04:00:00 EST 1995 · Physical Review Letters

DOI:https://doi.org/10.1103/PhysRevLett.74.2523· OSTI ID:27865

Schwarz, R B; Khachaturyan, A G ^[1]

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1. Center for Materials Science, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

We develop the thermodynamic theory for the decomposition of a ``coherent`` two-phase open system consisting of an interstitial solid solution in equilibrium with a gas reservoir of solute atoms. It is shown that, contrary to what is expected for incoherent systems, the phase rule is inapplicable and the ``plateau`` on the pressure-composition isotherm does not correspond to two coexisting phases. The coherency strain introduces an unsurmountable macroscopic energy barrier between the transforming phases, which prevents the coexistence of the phases and results in a reversible hysteresis in the pressure-composition isotherm. The proposed theory is applicable to metal-hydrogen systems.

• OSTI ID: 27865
• Journal Information: Physical Review Letters, Journal Name: Physical Review Letters Journal Issue: 13 Vol. 74; ISSN 0031-9007; ISSN PRLTAO
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
CHEMICAL COMPOSITION
DECOMPOSITION
FREE ENERGY
INTERSTITIALS
ISOTHERMS
PHASE TRANSFORMATIONS
PRESSURE DEPENDENCE
SOLID SOLUTIONS
THERMODYNAMICS