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Information × Registration Number 0217U006819, 0115U002319 , R & D reports Title Formation of gradient states in nano layered metal film compositions via processes on the outer surface popup.stage_title Head Sydorenko Sergiy Ivanovich, Доктор фізико-математичних наук Registration Date 07-12-2017 Organization National Technscal University of Ukraine "Kiev Polytechnic Institute". popup.description2 Laws of energy induced diffusion phase-structural transformations in film functional-gradient materials with significantly different thermodynamic and crystal-chemical properties of the layers (V-Ag, Pd-Ho, Ni-Cu-Cr, etc.) were determined. "Diffusion pump" effect was determined for investigated nanothickness materials: physical and chemical processes on outer surface thermodynamically determine diffusion phase formation in the bulk during energy impact in argon-, nitrogen-, oxygen-, hydrogen- containing atmospheres and in vacuum of 10-3 Pa, 10-7 Pa. These laws have attributes of superposition of structural-concentration-phase distributions formation processes due to separation in time of different dominant diffusion mechanisms (boundary diffusion, bulk diffusion, surface diffusion) with "distortion" - because of nanothickness effect - of balance of that driving forces, which were historically accepted. As a sequence - in contrast with processes in bulk materials - during diffusion redistribution in such systems concentration gradients does not disappear, homogeneity of diffusion distributions does not achieve. Variations of atmosphere compound determine laws of phase-structural transformations and possibility to control lattice parameters, texture, grain size and surface morphology. At relatively low annealing temperatures, when dominant diffusion mechanisms is grain boundary one, formation of required phase could be achieved by grain boundaries migration. As a sequence behind the moving grain boundary reaction layer of required phase could be formed. Algorithm of materials "computer construction" was developed: on the bases of interpolation approach to big data massive related to materials structure and properties operation on the bases of interconnection of quantum-imitation modeling with the following experimental check of its results. Physical and chemical effects that were discovered in this work, determined laws of direct formation of gradients states via the processes on outer surface and developed theoretical approaches are scientific base of high technologies development of nanosized metallic compositions fabrication for micro- and nano- devices with new prospective properties (magnetic, electrical, corrosion, etc.). Product Description popup.authors Владимирсьий Ігор Анатолійович Сидоренко Сергій Іванович popup.nrat_date 2020-04-02 Close