465 research outputs found

    Structural-Strained State and Mechanical Characteristics of Single-Phase Vacuum-Arc Coatings of Multicomponent High Entropy System Ti-V-Zr-Nb-Hf and Nitrides Based On It

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    In this work was shown the high stability of the single-phase structural state of high entropy alloy of Ti-V-Zr-Nb-Hf system in a vacuum-arc method of obtaining of coatings based on it. In the process of deposition single-phase high entropy coatings with bcc-lattice which characterizes the cast state are formed in vacuum, and upon obtaining in a nitrogen atmosphere single-phase nitride superhard coatings based on fcc-metal lattice are formed. Such a stability of structure of multi-element alloy to high temperature evaporation and deposition from high-energy plasma flows allows to use the techniques developed for simple substitution phases in the analysis of their structural-stress state. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3480

    Structural-Strained State and Mechanical Characteristics of Single-Phase Vacuum-Arc Coatings of Multicomponent High Entropy System Ti-V-Zr-Nb-Hf and Nitrides Based On It

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    In this work was shown the high stability of the single-phase structural state of high entropy alloy of Ti-V-Zr-Nb-Hf system in a vacuum-arc method of obtaining of coatings based on it. In the process of deposition single-phase high entropy coatings with bcc-lattice which characterizes the cast state are formed in vacuum, and upon obtaining in a nitrogen atmosphere single-phase nitride superhard coatings based on fcc-metal lattice are formed. Such a stability of structure of multi-element alloy to high temperature evaporation and deposition from high-energy plasma flows allows to use the techniques developed for simple substitution phases in the analysis of their structural-stress state. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3480

    Multylayer vacuum-arc coatins Ti-Mo-N production and study

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    Structural-phase and Strained State of Vacuum-ARC Mo-N Coatings

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    The effect of substrate bias on the structural-phase and elastic stress-strained state during the formation of vacuum-arc deposited nanostructural coatings of the Mo–N system has been studied. An increase in the bias potential leads to (i) predominant [111] orientation of the growing molybdenum nitride crystals with a NaCl-type cubic lattice (Ξ³-Mo2N phase) and (ii) the appearance of a second phase with a body-centered cubic crystal lattice that is characteristic of pure molybdenum. The elastically strained (stressed) state of the coating is determined not only by the conditions of deposition, but also by the mechanical properties of a substrate. In order to provide for formation of coatings in a high-elastic-strained (stressed) state, it is necessary to deposit coatings onto substrates with high elastic modulus, which prevent metal flow at the interface. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3480

    Effect of Preparation Conditions in the Pressure Range of Atmospheric Nitrogen (2 ... 50) 10-4 Torr on the Structural and Phase State of the Vacuum-Arc Coatings of Mo-N

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    Nanocrystalline vacuum-arc nitride coatings possess the totality of unique structural states and properties (high hardness, wear resistance, oxidation stability, etc.). The coatings of the Mo-N system show a high hardness and low solubility of nonferromagnetic materials, thereby attracting great interest in their industrial use. Unfortunately, at present there is an apparent lack of information on the regularities of phase-structural state formation in the Mo-N system. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3535

    Structure, Substructure, Hardness and Adhesion Strength of Multiperiod Composite Coatings MoN / CrN

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    A comprehensive study of the influence of the thickness of the layers, Us and PN on the structural engineering to obtain high mechanical properties in multilayer composite MoN / CrN vacuum-arc coatings has been conducted by means of scanning electron microscopy with energy analysis, X-ray diffraction studies microindentation and scratch testing methods. It has been determined that in the studied PN (2- 30) 10 – 4 Torr, the content of nitrogen in the coatings varies from 6.3 to 33 at. %, which leads even at the greatest nitrogen content to the formation of lower phase by nitrogen, -Mo2N and isostructural CrN with the vacant sites in the nitrogen sublattice. The increase of thickness of the layers applied on the substrate in a stationary state promotes the increase of nitrogen content. Along with this, the lowest microdeformation and the average size of crystallites are formed at Ub – 300 V, which defines the achievement of greater hardness of 35 GPa and high adhesion strength, which resists the destruction, Lc5 187.6 N

    Influence of the High-Temperature Annealing on the Structure and Mechanical Properties of Vacuum–Arc Coatings from Mo/(Ti + 6 wt % Si)N

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    Scanning electron microscopy with energy dispersive element microanalysis, X-ray structural analysis, and microindentation were used to study the effect of the deposition conditions in a reactive nitrogen atmosphere on the growth morphology, phase composition, structure, and microhardness of vacuum–arc multilayer coatings produced by the evaporation of cathodes from Mo and (Ti + 6 wt % Si) both after their deposition and after high?temperature annealing. It has been established that the use of the composite cathode of Ti and Si allows the formation of the structure state inclined to ordering to form a two-phase compound from TiN and Ti5Si3 at high-temperature annealing. In this case the coating hard? ness increases to a value higher than 45 GPa

    Effect of Ion Irradiation on the Structural State of the Vacuum-Arc Nitride Coatings

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    The effect of irradiation with ions Ar+ (energy of 1 MeV and 1.8 MeV) and He (energy of 0.6 MeV) on the structure and mechanical properties of the vacuum-arc nitride coatings. It is shown that the level of exposure to radiation materials can be divided into 3 classes: a) β€œthe most persistent” - significant changes occur only on the substructure level (as an example - multi-element system Ti-Zr-V-Hf-Nb-Ta-N), b) β€œthe medium resistance β€œ- significant changes occur in the macro stress-strained state (as an example - the system Ti-N), c) β€œstructural variable” – significant changes in the macro-level and phase composition (as an example, the system Mo-N). When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3513

    Formation of Biphasic State in Vacuum-Arc Coatings Obtained by Evaporation of Ti-Al-Zr-Nb-Y Alloy in the Atmosphere of Nitrogen

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    By means of X-ray diffraction, transmission and scanning electron microscopy, energy dispersive spectroscopy and indentation methods, the effect of nitrogen atmosphere pressure on composition, structure and hardness of vacuum-arc (Ti-Al-Zr-Nb-Y)N coatings during the deposition process has been studied. The two-phase state of the coating with solid-solution metal component (bcc lattice) and nitride phase (fcc lattice) have been formed. Increasing the pressure of nitrogen atmosphere leads to the increase of nitrogen component in the coating as well as to increase of the ordering regions size, allowing to achieve the hardness of H 49 GPa at a pressure of P 0.5 Pa. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3446
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