Thermodynamic properties of hydrogen in palladium and its alloys under conditions of constant volume

Abstract

Thermodynamic properties for the solution of hydrogen in palladium and its alloys are experimentally determined under conditions of constant pressure (corresponding to a free surface solid). In this research these data are converted to conditions of constant alloy volume. For palladium/hydrogen it is predicted that the phase change, α→β, which is so characteristic of this system, no longer appears under conditions of constant volume. This is indicative of the fact that long range dipole-dipole elastic interactions predominate in this system.A different sequence of behaviour of ΔµxsH→0 values with atom fraction of substituted metal is predicted for alloys of the type palladium + group IB for constant volume conditions as compared with conditions of constant pressure.