Phase stabilities of Pd-based alloys for membranes for hydrogen gas separation: A statistical thermodynamics approach

摘要

A statistical thermodynamics approach based on the cluster variation method (CVM) is put forward for designing new Pd-based membrane materials. The tetrahedron approximation of CVM coupled with effective pair potentials is used to describe the phase boundaries between alpha- and beta-phases in Pd-alloys-hydrogen systems. The model takes into account the volume changes during alpha-beta transitions, and the possible order-disorder transitions. In principle, the method allows to predict the phase boundaries of new, not yet synthesized, ternary alloys using effective pair potentials determined based on experimental data of known binary Pd-alloys.