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В статье рассматриваются проблемы квалификации мошенничества с использованием электронных средств платежа.

В статье рассматривается проблема квалификации посредничества во взяточничестве.

The paper presents the adhesive strength measurements of the Ni–Cu surface alloy formed on a copper substrate at a different thickness of the transition layer. The formation of the surface alloy is provided by the low-energy high-current electron beam of a microsecond duration; the different thickness of the transition layer is varied by the thickness of the nickel film sputtered. The multiple deposition-irradiation process is performed during one vacuum cycle. It is found that the cross-section of the film (Ni)-substrate (Cu) interface is rather developed and curved. The transition layer thickness reduces with increasing thickness of the deposited nickel film. Scratch testing shows that the adhesive strength of the Ni–Cu surface alloy obtained by using the low-energy high-current electron beam, is higher than that of the sputter-deposited surface alloy. The highest adhesion is observed for the Ni–Cu surface alloy obtained by the nickel film deposition 0.125 μm thick. In this case, the crack formation and localized film delamination occur under the critical loads of 15 and 17 N, respectively. Nevertheless, a complete delamination of the surface alloy is not observed.

A complex model for supercomputing the parameters of radiation-induced thermomechanical fields in heterogeneous media of a complex dispersed structure is developed. A technique for calculating the parameters of the photon-electron cascade generated in the object by the interaction of radiation with matter is constructed. A geometric model of the medium with a direct resolution of its microstructure is worked out. The model of the detecting system for the statistical evaluation of the energy deposit of radiation is part of the geometric description of the medium. The continuum mechanics equations taken in the Euler form of the conservation laws are the base for calculating thermomechanical processes. The results of trial simulations in the form of the calculated thermomechanical fields are presented.

Results of investigations of acoustic signals induced in a copper plate irradiated with a microsecond lowenergy high-current electron beam (LEHCEB) are presented. The characteristic acoustic signal waveforms, their amplitudes, phases, and frequencies are experimentally measured. It has been established that the acoustic signals induced by LEHCEB irradiation have groups of characteristic spectral components with fundamental frequencies of 6, 11, 22–24, 80, and 100–120 kHz whose amplitudes increased with charging voltage. It has been established that from the change of the 80 kHz harmonic with the charging voltage, the beginning of LEHCEB generation, its stable or unstable phase, and the beginning of target melting can be traced. It has been found that for a fixed charging voltage of each pulse in a series, the amplitude and phase-frequency structure of acoustic signals are almost the same.

The paper presents research results of the synthesis of Ni–Al surface alloy performed in a single vacuum cycle via magnetron sputtering of Ni (0.5 μm)–Al (1.5 μm)–Ni (0.5 μm) composite coating onto a steel substrate and its successive single pulse irradiation with low-energy, high-current electron beam (LEHCEB) of a microsecond duration. The numerical solution of the heat equation is used to determine the optimum LEHCEB modes which provide melting of all the films deposited. It is shown that the single pulse irradiation of thin films leads to the formation of the surface alloy consisting mainly of high-melting-point NiAl intermetallic phase. The structure of the surface alloy is a 2 μm thick homogeneous coating with 2×4 μm globules beneath separated by a thin layer of the substrate material. It is found that the wear resistance of the obtained Ni–Al surface layer is 2.7 times higher than that of the untreated steel substrate.

The formation of nanowhiskers in tungsten-containing syntactic foam under nanosecond relativistic electron beam has been experimentally studied. It has been demonstrated that a single impact of relativistic electron beam with a flux density of 230–240 J/cm2 and a total pulse duration of 150 ns on syntactic foam leads to the collapse of microspheres of more than 40 μm in diameter with the formation of filamentous structures up to 10 μm in length and about 100 nm in diameter on their surface. There is complex kinetics of substance ablation from the irradiated surface at a gas-plasma formation expansion rate of ~13 km/s. It has been found that nanowhiskers do not form near the emission “crater” from syntactic foam where the duration of the mechanical pressure pulse is minimal and close to the relativistic electron beam impact.

Recently, the emergence of accelerators of high-current electron beams and powerful electron ion beams has contributed to the creation of unique effects of concentrated energy flows on materials. Upgrading of production processes and development of new technological processes of both domestic aircraft propulsion engineering and aviation arms remain topical and needed. Engine operational reliability depends on that of turbine blades. They are the most loaded details because they are experienced to action of static, dynamic and cyclic loadings as well as are subjected to cyclic thermal stresses. Therefore the main objective of our paper is to analyze the effect of high-current electron beam irradiation on-resistance of sulfide-oxide corrosion (SOC)of Ni-Cr-Al-Yion-plasma coatings. To achieve this purpose, beam irradiation was performed using the RITM-SP complex automated electron-beam setup. Modification of surface layer of SDP 2+VSDP16 ion-plasma coating by microsecond high-current electron beams of selected mode made it possible to increase considerably the SOC resistance. An analysis of the surface and microstructure of samples after SOC testing enabled to determine different effects of medium on sample coating depending on the state of the sample surface. When investigated samples microstructure, we found that after modification certain cracks on sample surface did not develop in the course of testing. It was found that some craters were not necessarily centers of corrosion damage origin, i.e., the existence of given types of craters and their impact on SOC resistance stability are ambiguous.

In this work, a set of coupled equations is presented that describes the spot size and pulse length evolution of a Kerr focused ultra-short laser pulse in a turbulent and group velocity dispersive atmosphere. Solutions to the equations are compared against Monte Carlo simulations for focused and collimated beams in weak, moderate, and strong turbulence. The results indicate good agreement except when the beam accumulates excessive wings in the transverse profile and/or undergoes pulse splitting, such that the self-similar evolution assumption in the coupled equation derivation breaks down.

The study of the influence of electron-beam treatment on the structural features of a TiNi powder alloy obtained by calcium-hydride reduction is carried out. It is found that electron-beam treatment leads to homogenization of the phase and chemical composition of the surface layer of the TiNi powder alloy, smoothing of the surface relief of TiNi powder particles, and the healing of the defects on their surface. It is shown by energy dispersive X-ray spectral microanalysis that the concentration of Ti in the surface layer increases. This is due to recrystallization of this layer containing Ti2Ni particles during its remelting under the influence of the high energy density of the electron beam during treatment.

The results of numerical and experimental studies on the synthesis of a Ni-Al surface alloy on a steel substrate are presented. The alloy was formed by the preliminary magnetron sputtering of the multilayer Ni-Al coatings of two types, consisting of thin (type I) ∼ 0.1 and thick (type II) $\sim 1\ \mu\mathrm{m}$ films, followed by their irradiation and mixing with a pulsed electron beam transported to the samples in a plasma-filled diode. In the work, the optimal irradiation mode was determined by the numerical method of forming the Ni-Al surface alloy, in which intense melting of all deposited films occurs, and there is no evaporation of the surface material. It is experimentally shown that the Ni-Al surface alloy, which is represented by NiAl high-temperature intermetallic phase, is formed by pulsed electron-beam melting. For the Ni-Al multilayer system consisting of thin films, the surface alloy formed is homogeneous, but a network of cracks appears on the surface. For the Ni-Al multilayer system consisting of thick films, the surface alloy formed is heterogeneous, both along the surface and along the depth of the target. Its structure is a composite that combines the alternation of hard (but brittle) and soft (but ductile) components corresponding to NiAl high-temperature intermetallic phase and (Al, Ni, Fe) solid solution, respectively. Such a structure of the Ni-Al surface alloy makes it possible to obtain a crack-free surface with high tribological and high-temperature corrosion properties.

The synthesis of the surface Ni-Al alloy on a steel substrate is numerically studied. Surface alloys have a significant advantage over coatings since they provide the highest level of adhesion. Heat resistant alloys based on nickel-aluminum are widely used in engineering due to their low density, combination of high thermal conductivity and fracture strength at high temperatures. The application of the Ni and Al multilayer structure for the formation of the surface Ni-Al alloy by the method of liquid-phase mixing is studied. The effect of geometry parameters such as thicknesses of layers is considered. At a certain ratio of effective layer thicknesses the melting threshold of the multilayer structure is minimal.

Recently, Ti–Ta-based metallic glass surface alloys (MGSAs) with attractive surface properties were successfully synthesized on TiNi substrates by additive pulsed melting of film/substrate systems. However, undesirable nanobubbles are often formed in the amorphous matrix. In this work, to reveal bubble characteristics and clarify the origin of its formation, the ∼1.5-μm thick Ti–Ta–Si–Ni MGSA was synthesized by 10-fold alternating of magnetron co-deposition of Ti60Ta30Si10 thin (100 nm) film and its pulsed e-beam (∼2.5 μs, ∼15 keV, 1.7 J/cm2) melting with a TiNi substrate. Transmission electron microscopy was utilized for quantitative analysis of bubbles. It has been shown that the Ar trapped during film deposition is the majority gas inside the bubbles. The Ar pressure inside the bubbles with mean diameter in range of ∼9 ÷ 16 nm predicted from the equation of state for Ar at 300 K varies in depth from ∼100 to 50 MPa. Experimental results and estimates of diffusion of Ar atoms in the surface melt indicate that nucleation and growth of bubbles occur in the Ar supersaturated liquid phase at the solidification/glass transition front. A high bubble-forming ability of Ti–Ta–Si–Ni system is consistent with the facts that Si addition decreases the melt surface tension and increases the Ar diffusivity due to eutectic reactions.

The paper investigates the regularities of the formation of Cr-Zr surface alloy using a low-energy high-current electron beam (LEHCEB). The influence of the electron-beam processing parameters and the magnetron deposition parameters on the elemental composition of the formed Cr-Zr surface alloy is estimated. It is shown that, for all considered modes, there is a general tendency to a decrease in the chromium content in the surface alloy with an increase in the energy density or the LEHCEB processing pulse number. The thickness increasement of the chromium film applied in one cycle or the surface alloy total thickness increasement leads to an increase in the chromium content in the surface alloy. The LEHCEB processing parameters, namely the energy density and the number of pulses, have a greater effect on the chromium content during the formation of the Cr-Zr surface alloy in comparison to the magnetron sputtering parameters, namely the deposited film thickness and the formed surface alloy thickness. A linear regression model that describes the chromium content in the surface alloy depending on the film thickness, the surface alloy total thickness, the number of pulses and the pulse energy density is proposed.

The paper presents the results of numerical simulation of the distribution of thermal fields during the formation of Cr-Zr surface alloy using a pulsed low-energy high-current electron beam (LEHCEB). The melting thresholds of the Cr-Zr system for different thicknesses of Cr films were calculated. The melting threshold of the Cr-Zr system increases linearly with increasing Cr film thickness. A linear regression dependency model of the melting threshold on the film thickness is proposed. Evaporation thresholds of the Cr-Zr system for different thicknesses of Cr films were calculated. The evaporation threshold of the Cr-Zr system increases linearly with increasing Cr film thickness. A linear regression dependency model of the evaporation threshold on the film thickness is proposed. The value of the LEHCEB energy density at which the lifetime of the film and substrate are equal is calculated. This value is a maximum value for the effective formation of Cr-Zr. A model of the LEHCEB energy density, at which the lifetime of the film and the substrate are equal, in the form of a third-degree polynomial is proposed.

The paper deals with the formation of the stainless steel-copper surface alloy which occurs during the single vacuum cycle. Deposition of the stainless steel film onto a copper substrate is performed via successive magnetron sputtering followed by its liquid-phase mixing with copper using the low-energy, high-current electron beam of microsecond length. Numerical calculations are used to identify the optimum irradiation modes for the surface alloying. It is found that the optimum irradiation modes provide the homogeneous surface alloying, and the copper concentration in the obtained layer increases with the increase in energy density of the low-energy, high-current electron beam. The formation of the stainless steel-copper surface alloy increases the wear resistance of copper specimens by 7.5 times as compared to the original specimens. In addition, it is ascertained that the wear resistance of the surface alloy exceeds that of the common film coating (1 μm) more than 5 times.

A technique for the numerical simulation of electromagnetic wave propagation in materials with permittivity depending on the frequency is presented. The technique is based on numerical solutions of Maxwell equations with additional integral components in the bias current density. The technique to calculate the bias current density in dispersive media is represented and the corresponding modification of finite-difference scheme for Maxwell equations developed earlier is carried out. The electromagnetic pulse propagation in solid-fuel power systems is calculated.

The description and the main performance specifications are presented for a device in which a high-current electron gun and a magnetron sputtering system are integrated in a common casing. This device is efficient for surface alloying on metallic materials. It is shown that the magnetic system of the magnetron does not degrade the characteristics of an electron beam that is formed in the gun and passed through a hole in the magnetron sputtering system.

Using the methods of numerical integration, a temperature field has been calculated that arose in the surface layer of titanium nickelide target with NiTi2 intermetallic inclusions during irradiation by a lowenergy high-current electron beam with a duration of the order of a microsecond. The calculated temperature field has been compared with that obtained previously for a target of stainless steel 316L containing MnS inclusions. It has been found that, as in the case of stainless steel, the regions of inclusions are overheated. However, the temperature increase for NiTi2 (12 K) is significantly lower than in the case of stainless steel 316L (283 K). The dynamics of melting of these systems are also considerably different.

In this paper, we consider the conduction current excited in a silicon obstacle by the action of an external flux of penetrating radiation. We use quantum kinetic equations for distribution functions of conduction band electrons and holes of the valence band in the phase space of coordinates and quasi-momentums. Effective masses, densities of states, and group velocities of particles are determined on the base of band theory of a crystal. The approximation of the continuous momentum losses due to scattering on lattice defects is performed. The applicability of the model is validated by the comparison with the experimental data for the electron average-velocity dependence on the electric-field strength and on the velocity of the electron-energy transmission to the lattice. The silicon radiation conductivity excited by a free-electron current is calculated and the compliance of the results with the theoretical estimates is demonstrated.

Irradiation of TiNi shape memory alloys with a microsecond low-energy (10–30 keV), high-current (10–25 kA) electron beam in surface melting modes induces microcrater formation, which limits the practical use of this method of surface modification. Potential centers of crater formation are inclusions, which are inherent to TiNi alloys. However, there is limited information about their role in crater formation and the nature of this phenomenon as applied to TiNi alloys. In this paper, the microstructural identification of inclusions was carried out in commercial (VIM) and precision TiNi alloys using TEM/SAED/EDS methods. The topographical features of microcraters formed by a single-pulse irradiation of TiNi samples near the surface melting threshold of the B2 matrix phase were identified. It was found by SEM/EDS-analysis, that microcraters are mainly nucleated on titanium oxycarbide TiC(O) (commercial alloy) and oxide Ti 4 Ni 2 O (precision alloy) inclusions; in both cases, the central region of microcraters is enriched with oxygen. The role of gradient capillary forces in the melt mass transfer (Marangoni effect), which determine the formation of microcraters, was analyzed. It was shown that thermocapillary forces play an insignificant role, while chemicapillary forces induced by decreasing a surface tension of the melt due to its oxygen enrichment can be sufficiently large to produce microcraters.

An important factor limiting the wide application of thin-film metallic glass (TFMG) coatings for improving the surface-sensitive properties of structural alloys is the poor adhesion of TFMG to substrates. This problem can be overcome through the synthesis of MG surface alloys (MGSAs) by additive pulsed electron-beam melting of film/substrate systems of high glass-forming ability. In this work, this approach is applied to the [film (Ti60Ta30Si10, at.%, 100 nm)/substrate (TiNi alloy)] system using a low-energy, high-current electron beam (~2.5 μs, ~15 keV, 1.7 J/cm2) at 10 synthesis cycles and 10 pulses per cycle. Using SEM/WDS, XRD and cross-sectional HRTEM/EDS/SAED analyses it has been found that ~1.5 μm thick SA has completely MG structure, in which the near-surface ~500 nm thick Ni-depleted layer has composition ~Ti56Ta23Ni11Si10. Beneath the MGSA, the ~200 nm thick nanocomposite Ti50Ni30÷40(Ta + Si)20÷10 sublayer, consisting of Ti2Ni nanograins embedded in the amorphous phase is formed. The nanocomposite sublayer is followed by the intermediate sublayer with the eutectic columnar nano-grain B2-structure, which provides the diffusion bonding of MGSA with unmelted TiNi substrate. The monotonic depth dependences of hardness, elastic modulus, depth recovery ratio and plasticity, obtained by indentation, indicate the mechanical compatibility of the MGSA and underlying sublayers with the TiNi substrate. The adhesion-related failure of the MGSA during scratch testing proceeds in the ductile mode mainly through the plastic flow of intermediate sublayer. Evaluation of shape memory effect and superelasticity by torsional deformation technique has shown that synthesis of the MGSA results in an almost 2-fold increase in the martensitic shear stress and significant decrease in the stress hysteresis width compared with the untreated TiNi samples. The irreversible residual strain is ~0.8% at a maximum strain of 6%. Potentiodynamic polarization measurements have shown that synthesis of the MGSA results in the significant enhancement in corrosion resistance of test samples in the Lock-Ringer salt solution.

An important factor limiting the wide application of magnetron-sputtered amorphous or nanocomposite thin-film coatings for improving surface-sensitive properties of structural alloys is the poor adhesion of coating to substrate. This problem can be overcome through the synthesis of surface alloys (SAs) by additive pulsed electron-beam melting of film/substrate systems of high glass-forming ability (GFA). In this work, this approach is applied to the “film (Ti85/70Nb15/30, at.%), 100 nm/substrate (TiNi SMA)” system using low-energy, high-current electron beam (~2.5 μs, ~15 keV, 1.7 J/cm2) at 10 synthesis cycles and 10 pulses per cycle. The melting/solidification conditions were evaluated using numerical modeling of pulsed heating, taking into account the formation of eutectic in the Ti-Ni-Nb system and initial temperature risen up to 473 K to the end of the synthesis. Using surface SEM/EDS, AES, XRD and cross-sectional HRTEM/EDS/SAED analyses it has been found that both SAs of thickness ~1.5–2 μm have depth-graded structure, in which outer Ni-depleted layer is the multiphase nanocomposite with quasicrystals followed by predominantly Ti-Ni-based amorphous sublayer. Beneath, the ~1 μm thick intermediate sublayer with eutectic columnar structures (B2 + Ti2Ni and B2 + Ti3Ni4 for first and second SA, correspondently), monotonic Nb substitution for Ni and diffusion transition to TiNi substrate is formed. Depth-graded structure of modified surface layers provides monotonic changes with depth in nanohardness, elastic modulus, depth recovery ratio and plasticity to the values of the TiNi substrate. For both SAs the evolution of structure in depth is in a reasonable agreement with glass forming composition range evaluated for Ti-Ni-Nb system using Miedema's model.

Effective performance of laser systems intended for power delivery on a distant object requires an adaptive optics system to correct the laser beam distortions caused by atmospheric perturbations along the propagation path. The turbulence-induced effects are responsible for beam wobbling, wandering, and intensity scintillation, resulting in degradation of the beam quality and decline of the power density on the target. Adaptive optics methods are used to compensate these negative effects. In its turn, operation of the Adaptive Optics System (AOS) requires a reference wave that can be generated by the beacon on the target. This report discusses the requirements to the beacon that can support optimal correction of the wavefront. Post-processing of the beacon-generated light field enables retrieval and detailed characterization of the turbulence-perturbed wavefront — data essential to control the adaptive optics module of a high-power laser system.

In this work a silver-brass surface alloy was produced directly on brass microelectronics parts in vacuum by alternating processes of Ag thin film deposition followed by a pulsed electron-beam mixing of deposited film and a top layer of the substrate without breaking vacuum. Thickness of produced surface alloy was ranging from 7 to $17\ \boldsymbol{\mu} \mathbf{m}$ . Investigation of cross-section of samples with formed silver-brass surface alloy revealed that the surface layer is divided by two zones of pure Ag followed by transition layer where the concentration of Ag drops from 100 to 0%. The investigation of adhesion properties of three types of coatings (1) silver-brass surface alloy, (2) Ag coating deposited by electroplating, and (3) Ag coating deposited by magnetron sputtering have been fulfilled. This investigation revealed the best adhesion properties for silver-brass surface alloy. Amplitude-frequency characteristics for different types of silver coatings have been measured.

Chromium-copper surface alloy was produced directly on the Cu electrodes in vacuum by alternating processes of Cr-Cu thin film deposition followed by a pulsed electron-beam mixing in melted phase of deposited films and a top layer of the substrate. Composition of produced surface alloy was ranging from 30 to 50 wt.% of Cr and from 70 to 50 wt.% of Cu, respectively. The thickness of produced Cr-Cu surface alloys was in the range $5-10\ \boldsymbol{\mu}\mathbf{m}$ . It was established that produced Cr-Cu surface alloy consists of the very small-size particles of Cr of ∼ 10 nm in diameter embedded into Cu matrix. High-voltage hold-off measurements showed an increased value of breakdown electric fields for the synthesized Cr-Cu surface alloy compared to a Cr-Cu alloy produced by conventional powder metallurgy method. Tribological tests demonstrated 5-times increase in wear resistance of synthesized Cr-Cu surface alloy compared to a Cr-Cu alloy produced by conventional method.

The regularities of surface cratering in commercial and precision TiNi alloys irradiated with a low-energy, high-current electron beam (LEHCEB) in dependence on non-metallic (TiC(O)) or intermetallic (Ti2Ni) inclusions presented in TiNi matrix are studied. The melting threshold of TiNi alloy was found to be achieved in the range of LEHCEBs energy density E s corresponding to 1.3-1.5 J/cm 2 . The dominant role of non-metallic inclusions [mainly, TiC(O)] in the nucleation of microcraters was found. The processes initiated by pulsed heating/melting near the inclusion/matrix interface were analyzed. It is proposed that the most important factor enabling the liquid-phase dissolution of inclusions and delivery of impurities of C and O [from TiC(O)] and O (from Ti 4 Ni 2 O x ) into TiNi melt are eutectic reactions taking place in the Ti-Ni-C and Ti-Ni-O systems near Ti 50 Ni 50 composition.

The Cauchy problem for the kinetic and electrodynamic equations describing the propagation of an electron flow in a scattering medium and generation of self-consistent electromagnetic field is considered. The electron distribution function is defined in the space of finitely supported generalized functions. Algorithms for the simulation of scattering in the approximation of single and multiple collisions in a time step are presented. Specificities of application of this algorithm in a dense scattering medium and ionized region of large volume are considered.

In the present work, the adhesive strength of the surface alloy with different transition layer thickness was measured. A Ni-Cu surface alloy is formed using successive operations of Ni film deposition followed by mixing in a melted phase with the Cu substrate by a low-energy, high-current electron beam (LEHCEB). A different thickness of the transition layer was obtained by varying the thickness of Ni film deposited during the formation of the surface alloy. The study includes characterization of formed Ni-Cu surface alloys by scanning electron microscopy, in-depth elements distribution and scratch test. The results obtained showed correlation with thickness of the transition layer and adhesive strength of the surface alloy.

In the present work, the calculations of heat regimes for a Ni-Al surface alloy formed on a carbon steel substrate using a low-energy high-current electron beam (LEHCEB) were carried out for two types of multilayered systems with different numbers and thicknesses of the layers. The multilayered system of type 1 was three layered system Ni (0.5 µm)-Al (1.52 µm)-Ni (0.5 µm). The multilayered system of type 2 consists of 10 layers of Ni (0.1 µm each) alternating with 9 layers of Al (0.167 µm each). The total thickness of coating deposited in both cases was 2.5 µm. The melting thresholds for Ni, Al and carbon steel during LEHCEB irradiation were determined by the calculation. The phase diagrams obtained in calculation showed that process of melting occurs similarly for both types of multilayered systems. The calculation demonstrated that the melt thickness on the surface after irradiation by LEHCEB with optimal parameters is about 3 µm, and the average lifetime of the melt is ~ 1 µs (Ni-layers), and ~ 10 µs (Al-layers).

Ni-Al surface alloy electron beam synthesis results are presented. Surface alloy was formed on a carbon steel substrate by multilayer Ni-Al system deposition and subsequent one pulse low-energy high-current electron beam (LEHCEB) treatment in single vacuum cycle. It is shown that surface alloy containing mainly intermetallic phase NiAl is formed as a result of one pulse LEHCEB treatment. It is established that NiAl surface alloy microhardness and wear resistance are higher in comparison to steel substrate parameters.