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Information × Registration Number 0218U001476, 0115U000472 , R & D reports Title Experimental and theoretical studies of the dynamics of ionic and electromagnetic irradiation surface of multicomponent physical objects popup.stage_title Head Bobkov Valentyn V., Registration Date 19-04-2018 Organization Kharkov National University named after V.N. Karazin popup.description2 Object of research: chemical compounds; complex oxides; binary alloys; multilayer functional structures with tungsten or tantalum coatings on stainless steel; hydride forming metal alloys based on lanthanum and zirconium; functional materials that are used in science and technology, and are dielectrics, metals, semiconductors and natural minerals. The aim of the work: ascertaining regularities of the formation of particles in the excited state according the physical and chemical parameters of a solid body under ion irradiation; studying the mechanisms of accumulation and annealing of various types of radiation defects formed as a result of samples irradiation by He+ and D+ ions; determination of their influence on the crystalline structure of the tungsten or tantalum coatings and their surface; determination of radiation stability of such coatings in perspective multilayer functional structures for CTS installations; determination of the processes of hydrogen interaction with the surface of hydrogen storage alloys on the basis of lanthanum and getter alloys on the basis of zirconium on a monolayer level by secondary ions mass spectrometry; investigations of the mechanisms of short- and long-term instability of light reflection by the surface of these materials in vacuum and under temperature changes. Methods of investigation: ion-photon spectrometry, thermodesorbtion mass spectrometry, electron microscopy, secondary ions mass spectrometry, optical microscopy. The complex investigation of the basic parameters of the ion-photon emission of a number of materials having a significant difference in the crystalline structure was carried out. It was established that depending on the physical and chemical properties of a solid, different mechanisms of the formation of excited particles were realized. The formation of an excited state of flying-off particles may be due to the various mechanisms: the electron exchange between the flying-off particle and the solid; separation of the common cloud of electrons of a pair of colliding particles; the breakdown of the chemical bonds between the particles in the chemical compounds of metals; breaking of the chemical bonds between particles in chemical compounds of metals; breakup of knocked out complex excited compounds. The radiation resistance of the tungsten coatings of the composite structure (SSt. + W (?m)) to the successive irradiation with D+ and He+ ions and the tantalum coatings of the composite structure (SSt. + Ta (?m)) to the single irradiation with He+ or D+ ions was investigated. The spectra of thermal desorption of deuterium and helium from W and Ta coatings in vacuum were studied, coefficients of trapping of these gases in samples were determined. The types of generated radiation defects were determined and mechanisms of their accumulation and annealing in W and Ta coatings are proposed. The study of the dynamics of elementary processes of hydrogen interaction with the surface of hydrogen storage alloys LaNi4.75Al0.25, LaNi4.5Mn0.5 and getter alloys Zr2Fe, Zr33.3Fe16.7V50, Zr65Ti5V30, Zr37.7Ti4.7Mn20.2Fe37.4 at increased hydrogen partial pressures in the target chamber in the temperatures range 300 - 1000 K under irradiation by Ar+ beam with energy 8 - 16 keV was done. Studies of the properties of the surface, in particular its chemical composition, changing this composition depending on the experimental conditions, as well as the determination of the role of the components of alloys can provide useful information on the initial stages of interaction with hydrogen gas. The results of the study can be used to improve the metal hydride technologies of compressing, storing and transporting hydrogen in a chemically bonded state, creating extremely efficient systems of pumping and regulating supply of low pressure hydrogen in vacuum-plasma devices. The research results can be used in creating new materials with given properties in structural material science. The data on the short-term dynamics of reflection and scattering of light for a metal, dielectric, semiconductor, natural mineral were obtained. The mechanisms of reflection and scattering of light were proposed. Experimental data on long-term changes in temperature dependences of reflection and scattering were obtained. The mechanisms of observed processes were proposed. Research results can be used in the development of optical instruments operating in vacuum and cyclic temperature changes, for example, in space conditions. Product Description popup.authors І. Афанасьєва І. Оксенюк В. Бобков В. Бобков В. Літвінов Д. Шевченко Л. Тищенко О. Цапенко Р. Старовойтов popup.nrat_date 2020-04-02 Close