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An experimental technique of obtaining hardened palladium β-hydride consisting in saturation of work-hardened palladium with hydrogen under the conditions characteristic of the development of an α → β phase transformation is developed. Processes of recrystallization and reversal of its mechanical properties are investigated. The temperature of primary recrystallization of work-hardened palladium β-hydride is established. A comparative analysis of the plasticity of palladium hydride and of palladium following recrystallization annealing is performed.

Coherently conjugate wave-like swellings moving across the surface of PdH0.1 alloy at additional saturation with hydrogen under significantly nonequilibrium conditions have been detected and video recorded for the first time. The shape and character of motion of these swellings are similar to those of solitary waves of translation—solitons. The detected moving soliton-like swelling has been phenomenologically analyzed based on the modern concepts of metal-hydrogen systems. It is emphasized that the formation of these soliton-like coherent moving swellings is a peculiar (unknown previously) mechanism of relaxation and equalization of internal stress in metal-hydrogen alloys.

Upon additional saturation of a PdH0.1 alloy with hydrogen under highly nonequilibrium conditions, moving coherently conjugate undulatory swells, (whose shape and character of motion resemble those of solitary translational waves—solitons) on the surface have been for the first time fixed and recorded on video tape. Based on modern concepts about the metal-hydrogen systems, the observed soliton-like moving swell and the mechanism of its formation and motion have been discussed. Emphasis has been placed on the fact that the incipient formation of soliton-like coherent moving swells is a special previously unknown mechanism of relaxation and leveling-off of internal stresses in metal-hydrogen alloys.

Changes in the grain and fine structures of palladium that occur after the occurrence of reverse β → α hydride phase transformation in the metal are studied. It is shown that hydrogen treatment does not change the microstructure of palladium but strongly affects its fine structure.

It has been established experimentally that the hydrogen effect on deformed palladium activates the recrystallization process and recovery of mechanical properties. The temperature range of the recovery of mechanical properties is shifted toward lower temperatures under the action of dissolved hydrogen. When the pressure of gaseous hydrogen is raised during isothermal recrystallization annealing and, correspondingly, the amount of hydrogen dissolved in the metal increases, the accelerating effect of hydrogen naturally enhances. All the experiments have been performed under the conditions where it is the physical component of the hydrogen effect that affects the recrystallization processes in the metal. This component is known to cause an increase in the concentration of equilibrium vacancies and growth of the diffusive mobility of atoms in the crystalline matrix, a change in the stability and mobility of dislocations, etc.

It has been established experimentally that the hydrogen effect on deformed palladium activates the recrystallization process and recovery of mechanical properties. The temperature range of the recovery of mechanical properties is shifted toward lower temperatures under the action of dissolved hydrogen. When the pressure of gaseous hydrogen is raised during isothermal recrystallization annealing and, correspondingly, the amount of hydrogen dissolved in the metal increases, the accelerating effect of hydrogen naturally enhances. All the experiments have been performed under the conditions where it is the physical component of the hydrogen effect that affects the recrystallization processes in the metal. This component is known to cause an increase in the concentration of equilibrium vacancies and growth of the diffusive mobility of atoms in the crystalline matrix, a change in the stability and mobility of dislocations, etc.

Strengthening of palladium using hydrogen-induced transformation hardening (“hydrogen phase naklep” (HPN)) in the course of the reverse β → α hydride phase transformation in palladium-hydrogen alloys has been studied. It has been shown that the degree of HPN is mainly determined by the difference of the specific volumes of the transforming phases. As the transformation temperature decreases and the difference of the specific volumes of the transforming phases increases, the degree of strengthening of palladium during HPN systematically increases and its plasticity decreases, which is accompanied by an increase in the dislocation density and magnitude of microdistortions and by a decrease in the dimensions of the mosaic blocks.

The density of electrons created by microwave preionization in CO2, N2, He, and their mixtures was determined in the pressure range 4–27 kPa. When the energy deposited in the active medium was low (from 0.04 to 0.4 J per pulse), the electron density ranged from 2×107 to 1010 cm−3 in a chamber of 0.2-liter volume.