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

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

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

Structure, Adhesion Strength and Corrosion Resistance of Vacuum Arc Multi-Period NbN/Cu Coatings

The influence of deposition modes on the phase-structural state, corrosion resistance, and adhesive strength of vacuum-arc multi-period NbN/Cu coatings is studied. It was found that in thin layers (about 8 nm, in a constant rotation mode), regardless of the change in the pressure of the nitrogen atmosphere, a metastable δ - NbN phase forms (cubic crystal lattice of the NaCl type). At a layer thickness of ~ 40 nm or more, a phase composition changes from the metastable δ - NbN to the equilibrium ε - NbN phase with a hexagonal crystal lattice. In the presence of the ε - NbN phase in the niobium nitride layers, the highest adhesive strength is achieved with a value of LС5 = 96.5 N. Corrosion resistance tests have shown that for all the studied samples the corrosion process has mainly an anodic reaction. The highest corrosion resistance was shown by coatings obtained at a pressure of 7·10-4 Torr, with the smallest bias potential of -50 V and the smallest layer thickness; with a thickness of such a coating of about 10 microns, its service life in the environment of the formation of chloride ions is about a year

Influence of Thermal Factor and Radiation Processing on the Structure and Stress State of TiC-WC System Ion-plasma Coatings

The deposition temperature and proton radiation influence on the structure and stress-strain state of Ti‑W‑C system ion-plasma coatings was studied by the methods of wide-angle X-ray diffractometry combined with tensometry. It is found out that during sputtering MeC targets (where Me is a solid solution in the lattice of Ti and W atoms) when the ratio Ti / W reduces the transition from the one-phase state from (Ti, W)C carbide to the two-phase state takes place where the second one is represented by the lower in carbon a‑W2C‑phase. Formation of lower phases correlates with depleting the composition by the interstitial element (C) while the content of W in the coating increases that has a relatively small heat of the carbide formation value. Essential changes under irradiation with protons of 200 keV to dose of 6.5×1017 cm-2 occur only in a stress-strain state

Regularities in Forming the Phase Composition, Structure, Substructure and Growth Morphology of Nanostructured Ion-plasma Coatings of Quasi-binary Section Ti-W-B System

Using the method of X-ray analysis with the diffraction vectors in the plane and perpendicularly to the plane of growth of nanocrystalline W-Ti-B system condensates, regularities of forming the phase composition, structure and substructural characteristics were revealed. The designer’s software package «ScecDec» was employed to process the diffraction profiles. The deposition temperature and the ratio of Ti/W atoms in the coatings were used as influential parameters. The models to describe the obtained regularities are suggested. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3533

Influence of Thermal Factor and Radiation Processing on the Structure and Stress State of TiC-WC System Ion-plasma Coatings

The deposition temperature and proton radiation influence on the structure and stress-strain state of Ti‑W‑C system ion-plasma coatings was studied by the methods of wide-angle X-ray diffractometry combined with tensometry. It is found out that during sputtering MeC targets (where Me is a solid solution in the lattice of Ti and W atoms) when the ratio Ti / W reduces the transition from the one-phase state from (Ti, W)C carbide to the two-phase state takes place where the second one is represented by the lower in carbon a‑W2C‑phase. Formation of lower phases correlates with depleting the composition by the interstitial element (C) while the content of W in the coating increases that has a relatively small heat of the carbide formation value. Essential changes under irradiation with protons of 200 keV to dose of 6.5×1017 cm-2 occur only in a stress-strain state

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

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 (γ-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

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 and Properties NbN and Nb-Si-N Deposited by Magnetron Sputtering

NbN and Nb-Si-N films were deposited by magnetron sputtering the Nb and Si targets on silicon wafers at various bias voltage, Us. The films were investigated by an atomic force microscope (AFM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and nanoindentation. The deposited films were annealed to establish their thermal stability. The NbN films were nanostructured, and the Nb-Si-N films had a nanocomposite structure, and represented an aggregation of δ-NbNx nanocrystallites embedded into the amorphous Si3N4 tissue (nc-δ-NbNx/a-Si3N4)

Effect of Composition on Structure and Mechanical Properties of Ion-plasma Coatings of Quasi-binary System TiB2-WB2

For ion-plasma coatings of quasi-binary system TiB2‑WB2 the influence of composition on structure and adhesion strength has been analyzed. It has been determined, that the content of boron atoms in the coating increases with the increase of concentration of Ti, and the phase of (Ti, W)B2 is formed. Meanwhile, the strong bond Ti‑B, which is formed, leads to an increase of brittleness of the coatings. The greatest resistance to brittle cracks formation was inherent to the coatings with high W content in which the main phase is b-(W, Ti)B