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Copper powder spraying is under study: the PMS-1 feedstock copper, the copper that is mechanically milled in a high-energy planetary mill, and the copper that is also spheroidized in a plasma jet. High-density copper coatings are obtained using a CCDS2000 detonation facility. The Vickers microhardness of coatings $$H_{{\mathrm V}_{0.1}}$$ , obtained from feedstock and mechanically milled copper powders, increases from 110 to 160 and from 150 to 185, respectively, and the microhardness of coatings from the spheroidized powder is $$H_{{\mathrm V}_{0.1}}=165$$ . An X-ray phase analysis is carried out, and the resulting data indicate that, during the spraying, the copper oxide is partially reduced.

Results of studying the growth of diamond structures on steel specimens with the use of intermediate layers of molybdenum or tungsten carbide cemented by cobalt are reported. The interlayers are deposited by means of detonation spraying. Subsequent deposition of diamond films onto the clad steel specimens is formed by the gas jet method and a special thermocatalytic reactor with extended activating surfaces. The nucleation process on the interlayer surfaces is intensified by preliminary seeding of the specimens in a colloid solution containing nanodiamonds. Information about the phase and structural composition of the resultant specimens and about the film surface morphology is obtained by scanning electron microscopy, Raman spectroscopy, and X-ray diffraction analysis. The tribology of the specimens is studied with the use of hardness nansensors and by the Rockwell hardness indentation method.

Combustion and thermal decomposition of hydrocarbon fuels are used to produce different forms of carbon. Combustion in the detonation mode is of particular interest, as nanocarbon obtained under these conditions differs in properties from products synthesized by other techniques. A pulsed gas-detonation device designed on the basis of a CCDS2000 detonation spraying facility opens up new possibilities for manufacturing of nanocarbon. The device operates in a flow mode of gas supply into the reactor at the atmospheric pressure, which ensures high productivity and industrial safety of this method. Using detonation of acetylene-oxygen mixtures rich in acetylene, nanoscale carbon was obtained with particle morphology depending on the ratio of the components in the gaseous mixture.

In the present work, the microstructure of the cold sprayed coatings and the dependences of their main parameters (thickness, volume ceramic content and microhardness) on the used ceramic component in the powder mixture were studied. Ti and ceramic powders (B4C, SiC) mixtures were investigated. The presented results can be used to control the growth and properties of functional cold sprayed coatings in scientific and practical tasks.

A new pulsed-cyclic method of in-water gas combustion was developed with separate feed of fuel gas and oxygen with the focus on development of new technologies for heat generators and submerged propellers. The results of calorimetric and hydrodynamic measurements are presented. In-water combustion of acetylene, hydrogen, and propane was tested with the operation frequency of 2–2.5 Hz and with a linear injector. The combustion dynamics of combustion of stoichiometric mixture with propane (C3H8+5O2) was studied for a bubble near a solid wall; the produced gas bubble continues expansion and oscillations (for the case of linear and annular bubbles). It was demonstrated that gas combustion in annular bubbles produces two same-magnitude pulses of force acting on the wall. The first pulse is produced due to expansion of combustion products, and the second pulse is produced due to axial cumulative processes after bubble collapse. This process shapes an annular vortex which facilitates high-speed convective processes between combustion products and liquid; and this convection produces small-size bubbles.