Search academic texts

Information × Registration Number 0213U004842, 0113U006013 , R & D reports Title Hydrogen phase transitions in thin films and bulk specimens of metals. popup.stage_title Head Kosogor A., Registration Date 30-12-2013 Organization Institute of magnetism of NASU popup.description2 In the framework of the project the theoretical model based on the Landau theory of phase transitions has been developed, the theory accounts interrelation between crystal lattice symmetry and spatial hydrogen configuration. To this end the multicomponent order parameter has been compose: its isotropic part is proportional to the total hydrogen concentration, while its anisotropic part appears due to the hydrogen ordering along certain crystallographic axis and it is proportional to the probability of hydrogen occupation along singled crystal axis. Account of interrelation of this order parameter and symmetry of metal crystal lattice allows theoretical modeling of hydrogen solubility in thin films and bulk specimens of metals. The expression for Gibbs potential of hydrogen-metal system was derived, capturing interaction between hydrogen and metal crystal lattice. It has been shown that hydrogen pressure is not related directly to the order parameter of phase transition, but influence on phase transition characteristics due to energy coefficients renormalization. The phase diagram of hydrogen phase transitions in metals has been built and theoretical dependencies of hydrogen concentration in metal versus hydrogen gas pressure were derived for the calculation of solubility isotherms of hydrogen in metals. Product Description popup.authors Косогор А. popup.nrat_date 2020-04-02 Close