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Beresnev V.M.,Ukrainian Academy of Sciences | Sobol' O.V.,University of Kharkiv | Pogrebnjak A.D.,Sumy Institute For Surface Modification | Turbin P.V.,Sumy National Agrarian University | Litovchenko S.V.,University of Kharkiv
Technical Physics | Year: 2010

The results of studying the effect of high-tempera ture annealing in vacuum and in air on the phase composition, structure, and stressed state of ion-plasma condensates in the Zr-Ti-Si-N system are reported. In going from air annealing to vacuum annealing, the amount of active oxygen atoms decreases and the phase composition of the condensate remains stable to 1000°C or higher. A change in the crystal phase composition shows up, for the first place, in the crystallization of silicon nitride with the intense formation of hexagonal β-Si3N4 crystallites and also in the feeble formation of ZrO2 dioxide. The latter process does not lead to the decomposition of the (Zr, Ti)N solid solution: it merely increases the partial concentration of the titanium component. © 2010 Pleiades Publishing, Ltd. Source

Pogrebnjak A.D.,Sumy State University | Pogrebnjak A.D.,Sumy Institute For Surface Modification | Ponomarev A.G.,Sumy State University | Shpak A.P.,NASU G.V. Kurdyumov Institute For Metal Physics | Kunitskii Yu.A.,NASU G.V. Kurdyumov Institute For Metal Physics
Physics-Uspekhi | Year: 2012

The basic physics behind the interaction of ions with solid-state matter is discussed, with an emphasis on the forma- tion of interaction products between the ions and target atoms. Processes covering modification of high-resistance materials for use in small-sized 3D structure technology are described. Current trends in and problems facing the development of the scanning nuclear microprobe (SNMP) are reviewed. The appli- cation of slow positrons to diagnosing materials is examined and the techniques of positron microscopy and microprobing are presented. The potential of near-field microwave microscopy for diagnosing superconducting ceramics and of microwave microscopy for nanotechnology applications are assessed. The examples given include the use of micro- and nanoprobes to analyze nanoobjects (such as green algae cells with 3D-distrib- uted microelements, etc.), to develop the topological aspects of integrated microcircuits in nanoelectronics, and some other applications. The role of iron in pathogenesis of Parkinson's disease is highlighted, the latter being the subject of research in neurochemistry. © 2012 Uspekhi Fizicheskikh Nauk, Russian Academy of Sciences. Source

Pogrebnjak A.,Sumy State University | Bratushka S.,Sumy Institute For Surface Modification | Levintant N.,Polish Institute of Fundamental Technological Research
Ceramic Engineering and Science Proceedings | Year: 2011

The surface layer of an equiatomic TiNi alloy, which exhibits the shape memory effect in the martensitic slate, is modified with high-dose implantation of 65-keV N+ ions (the implantation dose is varied from 10 17 to 1018 ions/cm2). TiNi samples are implanted by N+, Ni+-N+, and Mo +-W+ ions at a dose of 1017-10 18cm-2 and studied by Rutherford back scattering, scanning electron microscopy, energy dispersive spectroscopy, X-ray diffraction (glancing geometry), and by measuring the nanohardness and the elastic modulus. A Ni+ concentration peak is detected between two maxima in the depth profile of the N+ ion concentration. X-ray diffraction (glancing geometry) of TiNi samples implanted by Ni+ and N+ ions shows the formation of the TiNi (B2), TiN, and Ni3N phases. In the initial state, the elastic modulus of the samples is E = 56GPa at a hardness of H = 2.13 ± 0.3 CPa (at a depth of 150 nm). After double implantation by Ni+-N+ and Mo+-W+ ions, the hardness of the TiNi samples is 2.78 ± 0.95 GPa at a depth of 150 nm and 4.95 ± 2.25 CPa at a depth of 50 nm; the elastic modulus is 59 GPa. Annealing of the samples at 550°C leads to an increase in the hardness to 4.44 + 1.45 GPa and a sharp increase in the elastic modulus to 236 ± 39 GPa. A correlation between the elemental composition, microstructure, shape memory effect, and mechanical properties of the near-surface layer in TiNi is found. Source

Pogrebnjak A.D.,NASU G.V. Kurdyumov Institute For Metal Physics | Pogrebnjak A.D.,Sumy Institute For Surface Modification | Pogrebnjak A.D.,Sumy State University | Shpak A.P.,NASU G.V. Kurdyumov Institute For Metal Physics | And 12 more authors.
Acta Physica Polonica A | Year: 2011

Using the two technologies: plasma-detonation and vacuum-arc deposition, we fabricated two types of coatings: Ti-Si-N/WC-Co-Cr/steel and Ti-Si-N/steel. We found that the top coating of Ti-Si-N was nanostructured one with 12 to 15 nm grain sizes and H = 40 to 38 GPa hardness. A thick coating which was deposited using the pulsed plasma jet, demonstrated 11 to 15.3 GPa hardness, an elastic modulus (E) changing within 176 to 240 GPa, and tungsten carbide grain dimensions varying from 150 to 350 nm to several microns. An X-ray diffraction analysis shows that the coating has the following phase composition: TiN, (Ti,Si)N solid solution, WC, W2C tungsten carbides. An element analysis was performed using energy dispersive spectroscopy (microanalysis) and scanning electron microscopy, as well as the Rutherford backscattering of 4He+ ion and the Auger electron spectroscopy. Surface morphology and structure were analyzed using scanning electron microscopy and scanning tunnel microscopy. Tests friction and resistance (cylinder-plane) demonstrated essential resistance to abrasive wear and corrosion in the solution. The decrease of grain dimensions ≤10 nm occurring in the top Ti-Si-N coating layer increased the sample hardness to 42±2:7 GPa under Ti72-Si8-N20 at.% concentration. Source

Sobol O.V.,Kharkiv Polytechnic Institute | Pogrebnyak A.D.,Sumy Institute For Surface Modification | Beresnev V.M.,Research Physicotechnological Center
Physics of Metals and Metallography | Year: 2011

Regularities of the formation of the phase and structural state and mechanical characteristics of vacuum-arc coatings produced by the evaporation of Zr-Ti-Si-N targets in a reactive nitrogen atmosphere have been studied. For the targets of compositions Zr 92.0 wt %, Ti 3.9 wt %, Si 4.1 wt %, and Zr 64.2 wt %, Ti 32.1 wt %, Si 3.7 % at a working pressure of the nitrogen atmosphere of 0.1-0.8 Pa and a potential at the sub-strate of -100 and -200 V, the formation of a single-phase crystalline state of the coatings (nitride of the solid solution of the components of the target) has been established. The size of crystallites is in the nanometer range (25-85 nm). An increase in the size of crystallites in the direction of the incidence of the film-forming particles (perpendicular to the growth plane) is favored by an increase in the bias potential from -100 to -200 V. The low heat conductivity of the metallic (Ti and Zr) components of the target leads to a significant content of a droplet phase when using the direct-flow regime of the vacuum-arc deposition and requires the employment of a technological scheme with a separation of the film-forming beams to increase the homogeneity of the high mechanical properties of the coatings. The use of film-forming beams separated from the droplet phase makes it possible to increase the homogeneity of the surface morphology of the coatings with the retention of a large index of plasticity (H/E = 0.8-0.9) and high hardness (33-37 GPa) of the material of the coating. © Pleiades Publishing, Ltd., 2011. Source

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