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X-ray diffraction has been used to study the phase composition and determine the lattice parameter of the β- and α-phases in foil of a Pd–Cu solid solution with a composition that ensures reversibility of the β $$ \rightleftarrows $$ α transformations: with the structure of the β- and α-phases and a two-phase structure. The thermal expansion coefficient of the Pd–Cu solid solution has been determined for the first time.

We have studied the phase composition and texture of a Pd–Cu solid solution with a nearly equiatomic composition in different steps of the preparation of membrane foil by rolling to 300, 175, 100, and 20 μm and 7-μm-thick foil produced by magnetron sputtering of a target having the same composition as the foil. We have identified orientation relationships between the β- and α-phases in the as-prepared two-phase structures and demonstrated that, after heating to 600°C and subsequent cooling, the ordered solid solutions (β-phase) prepared by the two processes, have identical textures, which can be understood in terms of the transformation mechanism.

The effectiveness of flash lamp processing and ion beam sputtering in surface cleaning of membrane foil from a Pd–Cu solid solution produced by rolling has been assessed using cyclic voltammetry and atomic force microscopy. It has been shown that it is reasonable to use cyclic voltammetry for assessing the degree of foil surface cleaning and that combined surface processing of membrane foil is effective in foil surface cleaning. Ion beam processing reproducing the surface elemental composition corresponding to the original composition of the solid solution and increasing surface roughness is a factor of 1.3 more effective than combined surface processing.

The β $$ \rightleftarrows $$ α phase transformations in foil of the Pd–52 at % Cu solid solution prepared by rolling have been studied using X-ray diffractometry and resistivity measurements during thermal heating–cooling cycles or lamp processing (LP) using light from high-power pulsed xenon lamps, followed by cooling. The results demonstrate that complete ordering of the two-phase (α + β) as-prepared (as-rolled) foil follows the sequence (α + β) → β → α → β in the first heating–cooling cycle and β → α → β in the second and subsequent cycles. When a radiative energy critical for a given thickness of foil with an ordered structure is delivered to the foil surface, an irreversible β → α phase transformation occurs, whose rate can be three orders of magnitude higher than the rate characteristic of the disordering process during Joule heating. After LP, the reversibility of the β $$ \rightleftarrows $$ α phase transformations, inherent in the initial, ordered structure, is observed in a second thermal cycle: heating to 700°C and cooling. The sequence of phase transitions is α → β → α → β in the first cycle and β → α → β in the second and subsequent cycles. The localization of light in the skin layer and finite thermal conductivity offer the possibility of producing a structure with a phase composition gradient at subcritical irradiation times. The fact that the LP-stabilized α-phase persists up to 300°C makes it possible to compare the mechanical properties of foil samples having identical elemental compositions but different (ordered and disordered) structures.

Hydrogen diffusion in palladium bicrystals containing a small-angle twist or tilt boundary or a large-angle boundary similar to a special boundary is investigated using molecular dynamics simulation. We assess the effect of grain boundaries on the hydrogen diffusion process. The types of grain boundaries considered here are shown to differ in their absorption activity for hydrogen. The temporal grain-boundary segregation of hydrogen atoms can be accounted for in terms of their coordination, which differs significantly from that in the grain bulk.

The present review details the results of studies that showcase the capacity of the molecular dynamics method to analyze the atomic structure of small-sized metallic objects: nanoparticles, thin films, and film heterostructures.