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Formula for intrinsic stress calculation in coatings deposited from ion flux in the pulse potential mode is derived. The case of deposition of ions with different charges is taken into account. The criterion of applicability of derived formula is proposed which permits determining critical parameters of the pulse potential mode. Calculation of stress in TiN coatings at deposition of low-energy ions Ti+ from filtered vacuum arc plasma is brought. The qualitative agreement of calculated stresses with experimental data is stated. The important role of deposition temperature for intrinsic stress control in deposited coating is noted.

Dependence of thermal conductivity of nanocrystalline diamond coating on grain size and form is theoretically investigated. Nanodiamond is considered as two-phase material composed of dielectric diamond grains characterizing by three main dimensions and segregated by thin graphite layers with electron or phonon thermal conductivity. Influence of thermal conductance type and thickness of boundary layer on nanodiamond thermal conductivity is analysed. Derived dependences of thermal conductivity on grain dimensions are compared with experimental data. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/35196

The experimental results of the effect of the gas phase composition on nitrogen-doped nanostructured diamond coatings synthesized in the glow discharge plasma on their structure and resistance have been presented. It was shown that changes in the electrical conductivity of the nitrogen doped nanostructured diamond coatings are primarily related to changes in the electrical conductivity of the grain boundaries and did not to changes in the grain size of the diamond phase. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/35189

The structure, mechanical and tribological properties TiN coatings рroduced with PIII&D by using rectilinear filtered vacuum arc plasma system are present. The results of scratch testing and wear reciprocating testing clearly revealed the positive effect of pulse bias (0.5÷2.5 kV) application on tribological behavior of the TiN coatings in comparison the coatings deposited with DC bias (150 V). Application of pulsed bias potential leads to a significant reduction in the friction coefficient and increasing of coatings wear resistance due to a change in their structure. The orientation of crystal planes parallel to the surface changes from (111) to (220) with the application of pulse bias, which is accompanied by a transition from fibrous grains structure to denser columnar grains. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/35187

A mode of pulse biasing of DLC coating deposition is theoretically investigated. In this mode a deposited ion flow of plasma with energy of E0 (20 200) eV is modified by superimposing of pulse potential ~ 1000 V. It was shown that intrinsic stress in a DLC coating can be decreased in several times without of essential decrease of sp3-bonded carbon concentration compared with DLC made in stationary mode deposition at E0 ion energy. A method of optimization of pulse mode parameters is proposed which is based on analysis of location of thermoelastic peaks of ions on phase P, T-diagram of carbon. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/35398

The plasma flow in a curvilinear duct is modelled using particle-in-cell method in the cylindrical geometry. The curvature of magnetic field lines in the duct is simulated introducing centrifugal force acting on ions. The electrons are assumed magnetized while the action of the steady magnetic field on the ions is neglected. The electric potential is calculated self-consistently. First the case when drift of the electrons is negligibly small is studied. There, starting from the certain plasma density, equilibrium can exist. It could be reached after some number of ions leaves the plasma column forming the potential well for the ions in the plasma core. An important point is that, at the equilibrium state, the distribution of electric potential is essentially asymmetrical. To avoid the high voltage plasma oscillations the found equilibrium is used as the initial condition for further calculations with finite steady magnetic field. The calculations show that the distribution of the electric field in the plasma duct remains asymmetrical. This causes the electrons to drift to the wall of the duct mainly in vertical direction.