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The modification of titanium surface under electrochemical polarization (EP) in the phosphate-alkaline solutions has been studied using the methods of X-ray diffraction, electron probe microanalysis, atomic force microscopy, X-ray photoelectron spectroscopy (XPS), cyclic voltammetry and spectroscopic ellipsometry. It is shown that the morphological parameters of the surface, e.g. roughness and stringiness, as well as its structural-chemical characteristics, e.g. preferred orientation, size and habit of crystallites, titanium chemical forms, thickness and phase composition of oxide film are generally dependent on the polarization potential. The characteristics of titanium surface modified at low anodic potentials 500, 750 and 1000 mV and 10-min polarization time have been measured. The processes of Ti surface dissolution and etching along grain boundaries are found to be most intensive at 750 mV. Under 500 mV, these processes are poorly developed yet, while at 1000 mV, the surface passivating film formation limits the previous processes. Despite relatively low polarization potentials (1 V), the surficial oxide films have sufficient thickness (up tõ 20 nm) and a specific multilayer structure of variable composition and oxidation state of titanium. The data obtained allow to assert that EP represents an effective tool for morphological and a structural chemical modification of a titanium surface.

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