Modern methods of recycling scrap tungsten pseudo-alloys are considered. The improvement of the method of electroerosive dispersion of conductive granules by strengthening its electrohydraulic action for effective disintegration of tungsten pseudo-alloys into micro-components is discussed.

In the present work for the first time, it is investigated the structure and chemical composition of the modified with oxygen groups, chlorine, and bromine carbon nanospheres (CNS) synthesized by the high-voltage high-frequency electrical discharge treatment of the propane–butane gas mixture. The composition and structure of CNS were studied by X-ray diffraction and Raman spectroscopy (RS). An increase in the intensities of X-ray reflexes (002) and wide-angle background in functionalized CNS-X (X = O, Cl, Br) was established. This is due to the electron density transfer from the X atoms to the CNS. The existence of regions of higher and lower ordering in the CNS is shown. A decrease in graphite interplanar distances with an increase in the number of electrons in functionalizing atoms was established. For the first time, the presence of a diamond-like structure (DLS) in electric-discharge CNS and its change during functionalization was confirmed by studying the structure of vibrational bands and observing spectral components in the regions of 1150–1260–1305 cm−1. A universal concept of the disordering of graphite and diamond-like structures by multiplying the unit cell sizes is proposed, which serves as a reliable basis for interpreting the structure of the observed vibrational bands.

The article presents a study of the structure and properties of carbon-containing nanostructured coatings obtained by electric discharge methods. X-ray structural analysis of coatings was carried out using a DRON-4-07 diffractometer with a copper tube. Images of the surface morphology were obtained using a JSM-6700F scanning electron microscope. The coating surfaces were examined using a Solver P47H atomic force microscope. The surface hardness of the obtained samples was determined using a ball with a diameter of 1.588 mm at a load of 588.4 N. The method of electric discharge treatment of carbon-containing gases allows to obtain a nanostructured coating of almost the same size particles that form micrometer globules. Nanocarbon coating has no impurities. Particle sizes are no more 40 nm. This coating is X-ray amorphous and attenuates X-rays at wavelength λ_k_α = 0,154,178 nm on average by 51

Oxides in the form of micro- and nanosized powder, containing agglomerates of particles with a high specific surface, were obtained by means of electric Ti and W wire explosion in the air. An X-ray phase analysis showed that the only product of Ti destruction is TiO2, while the electric explosion of W conductors results in the formation of WO3 + W2O7 mixture, in which tungsten anhydride WO3 dominates, and traces of a residual metallic W come across. The photocatalytic properties of electroexplosive powder were studied using a model oxidation reaction of methylene blue. It was revealed that both TiO2 and the WO3 + W2O7 mixture demonstrate catalytic activity within a wide spectrum of radiation, including the visible one. The catalytic activity of the WO3 + W2O7 mixture under ultraviolet and incandescent lamp radiation was inferior to that of TiO2; however, in the solar radiation, the rate of dye degradation with the participation of tungsten oxides is higher. In this case, the average rate of decreasing concentration of the dye in water containing a mixture of WO3 + W2O7 depends little upon the type of the radiation source.

— A series of electric explosions were carried out on single and twisted conductors of various diameters made of titanium (Ti) and tungsten (W) in propane-butane. Analysis of the electro-physical characteristics of the explosion showed that the process of resistive heating of the conductors is characterized by two monotonically increasing sections on the voltage and current curves, separated by a flat segment (plateau), which corresponds to a relatively stable specific electrical resistance of refractory metals in a liquid state. The energy introduced into the conductor during the resistive heating stage, which can be higher or lower than the energy of sublimation of the conductor and can be regulated by changing the external parameters of the discharge circuit, is a key indicator that determines the structural-phase state of the destruction products and the chemical interaction of the conductor. Conditions were realized under which micro- and nanosized powder products of the electric explosion do not contain residual metals and consist entirely of carbide phases (TiC with an average microhardness of 29 580 MPa in the explosion of titanium conductors, and a mixture of W 2 C + WC 1 – x dominated by stabilized high-temperature nonstoichiometric cubic carbide WC 1 – x with an average microhardness of 16 770 MPa in the explosion of tungsten conductors).

A series of electrical explosions in propane-butane of single and strand-connected Ti and W conductors with various diameters was carried out. Electrophysical characteristics of the explosion revealed that resistive heating of conductors is characterized by two monotonically ascending sections on the voltage – current curves separated by a flat segment (plateau), which corresponds to relatively stable electrical resistivity of refractory metals in the liquid state. The energy deposited by changing the power input into the conductor during its resistive heating, which can be higher or lower than its sublimation energy and can be regulated by changing the external adjustable parameters of the discharge circuit, is a key indicator determining the structural-phase state of destructed and chemically synthesized products after the explosion. The conditions are achieved under which micro- and nano-sized powder products do not contain residual metals and consist of carbide phases completely (TiC with an average microhardness of 29580 MPa as a result of the titanium explosion and a mixture of W2C+WC1-х, in which stabilized high-temperature non-stoichiometric cubic carbide WC1-x dominates, with an average microhardness of 16770 MPa as a result of tungsten explosion).

An analytical review of recent studies in the field of electrical explosion of conductors (EEC) has been performed to select modes and conditions of high-resistivity EEC, which is used to produce functional wear-resistant hard-alloy carbide coatings containing refractory metals, their carbides, and nanocarbon particles. The influence of the environment in which the EEC is carried out on the composition of the products obtained is analyzed. The influence of the conductor’s electric explosion modes in gaseous carbon-containing media on the synthesis of refractory metal carbides is considered. The problems of producing the functional composite coatings of metal surfaces are also discussed.

A system for controlling the process of the high-voltage high-frequency electric discharge synthesis of nanocarbon on metal surfaces in a carbon gas medium has been developed. The criteria that determine the production mode of the synthesis of nanocarbon are defined. The synthesis control is performed according to the minimax optimality criterion. It allows the current value in the range of the production mode of the synthesis of carbon nanomaterials with an onion-like structure to be maintained. The control of the movement of the metal surface sample with respect to the electrode in the course of synthesis ensures the uniformity of coating the surface with a layer of a synthesized nanocarbon material.

An experimental setup for depositing nanostructured carbon coatings on structural materials is described; it exploits the principle of the electric-discharge destruction of gaseous hydrocarbons to deposit the carbon nanoparticles onto a metal surface. The results of optical metallography, atomic force microscopy, and X-ray diffraction analysis suggest that a nanostructured amorphous carbon layer with a grain size of 50–80 nm and an arithmetic average roughness of 35–40 nm and that is capable of absorbing X-rays is present on the sample surface. The coating thickness can achieve 20–40 μm. The characteristics and growth mechanisms of the coatings depend on the ability of the substrate material to interact with carbon.

A system for controlling the process of high-voltage high-frequency electric-discharge synthesis of nanocarbon on metallic surfaces in a carbon-containing gas environ-ment has been developed. The criteria that determine the productive mode of the synthesis of nanocarbon are defined. The control is carried out by the minimax opti-mality criterion, which allows maintaining the current value in the range of the productive mode of the synthesis of carbon nanomaterials with an onion-like structure. The control of the movement of a sample of the structural surface relative to the electrode during the synthesis ensures the uniformity of the coating of the structural surface with a layer of a synthesized nanocarbon material.

Using X-ray diffraction, reverse Monte-Carlo methods and Voronoi-Delaunay analysis, the quantitative characteristics were established for a local structure in disordered carbon materials produced by the ball-milling of pristine graphite and high-frequency electric discharge treatment of hydrocarbon gases. Voronoi polyhedra of the synthesized carbon nano-materials are characterized by a wide distribution of topological and metric characteristics with a predominance of pentagonal faces typical for amorphous structures.

The properties of carbon nanomaterials, produced with the help of the method for the high-frequency electrodischarge processing of hydrocarbon gases, based on the creation of non-equilibrium plasma under variation of frequency and treated gas, have been studied. It is shown that the synthesis of onion-like structures and globular carbon nanoparticles with turbostratic structure is possible, depending on the type of gas.

The physical principles of synthesis of carbon nanomaterials by the electrical explosion of wires and electrical breakdown of organic liquids are described. A comparative analysis of these methods is performed. The phase composition and structural state of the obtained materials are studied in dependence on the energy parameters of electrical discharge and the chemical nature of the working medium.

It is experimentally set that realization of crown digit is possible in water solutions of weak electrolytes, such as polybasic organic acids. It is explored, as different factors on the amount of the synthesized nanocarbon at electro-bit treatment of solutions of oxalic and lemon acids is influenced.

The conditions necessary for performing a pulse corona discharge with a continuous plasma mass in a liquid containing carbon are determined. The organic compositions used as electrolytes have been chosen. There is proposed an approach to calculate the external controlled parameters of the pulse generator.

Terms, necessary for realization of impulsive crown digit with continuous plasma education in a liquid containing a carbon, are certain. The organic compositions used as electrolytes are chosen. Approach for the calculation of the external managed parameters of impulsive generator was offered.

A new method of the electro-discharge method to synthesize nanocarbon is designed, which provides high gradients of temperatures and pressure at the expense of a high speed of the input of energy in plasma channels. The morphological structure of the obtained nanocarbon is uniform; characteristic sizes of fragments are 9 up to 50 nm, the contents of chemically pure Carboneum reaches 97% (remaining О 2), that allows to eliminate labour-consuming operation of clearing nanocarbon at obtaining by electro discharge method.