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Information × Registration Number 0213U006863, 0113U007173 , R & D reports Title Influence of processes in outer surface thin metal layers on phase formation in the volume popup.stage_title Head Voloshko Svitlana Mykhaylivna, Registration Date 09-01-2014 Organization National Technscal University of Ukraine "Kiev Polytechnic Institute". popup.description2 The scientific hypothesis of the project was experimentally justified: The idea of the hypothesis is that processes that develop on the surface of layered compositions of metals and alloys are thermodynamically cause diffusion - controlling processes of mass transfer in volume. Unlike processes in bulk materials, concentration gradients for diffusion redistribution in such systems do not disappear, and the chemical and structural heterogeneity can not be achieved. The effect of surface structural and phase changes on diffusion in the bulk of polycrystalline thin film systems Cu Sn and Sn / Cu with layers thickness of 4 to 180 nm at thermal treatment in the temperature range of 373 - 523 K in a 10-3 Pa vacuum has been studied. It has been demonstrated that in the Cu/Sn system, an additional driving force for the diffusion towards the external surface occurs due to the effect of the outer surface oxygen activation. A condition for this effect implementation is higher affinity to oxygen of an element from the "bottom" layer, therefore at layers materials inversion in Sn/Cu system no surface oxygen activation occurs. It has been proved that annealing in vacuum and hydrogen as a result of thermally induced reaction diffusion in the bulk of the thin film systems based on Cu and Sn phase lead to formation of intermetallic compounds Su6Sn5, Su4Sn, Su3Sn - typical for a massive state, the sequence of their formation is not changed, but the temperature of their formation is lower comparing to the equilibrium phase diagram . Product Description popup.authors Волошко Світлана Михайлівна Довгопол Євгенія Олександрівна Замулко Сергій Олександрович Олешкевич Анна Ігорівна Потєшкін Сергій Олексійович Сидоренко Сергій Іванович popup.nrat_date 2020-04-02 Close