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The results of accelerated tests on the influence of climatic factors on the operational and technical parameters and characteristics of carbon fiber reinforced plastics are presented, among which the main attention is paid to thermal and moisture aging, thermal aging, joint periodic changes in temperature and humidity, as well as immersion in water on the state of polymer composite materials in order to check physical and mechanical properties and improving their quality. The results of the experimental studies made it possible to establish how much and in what direction the strength characteristics of the materials under study changed as a percentage of the initial value. Ref. 24. Tab. 6.

The paper presents the results of studying thermal stability of materials operating in a plasma jet under high temperature and rapid thermal load variation conditions. It has been shown that the use of plasma generators along with the introduction of various powder materials make it possible to simulate the operating conditions of the parts exposed to high-temperature gas flows containing heated particles. The effect of the introduced powder materials on the thermal stability of samples prepared by plasma spraying from molybdenum, as well as tungsten and tungsten-based compositions was studied. An experimental setup was proposed for evaluating the thermal stability of the composites and protective hardening coatings operating under high-temperature gas flows, which also allows determining erosion resistance.

The possibility of applying the method of ultrajet diagnostics for estimation of the stress–strain state (SSS) of carbon-fiber samples is considered. It was shown as a result of a series of experiments and numeric computations that informative parameters of the cavern do not contain objective information about the state of material in the current load state. This may be useful for the construction of a general method for diagnosing samples made of carbon fiber for estimation of their operational life, including the conditions of the effect of a set of external factors: static loading, temperature, various types of electromagnetic radiation, et al. Experiments showed there to be high indicators of correlation between computed values of stresses and depths of caverns formed as a result of ultrajet impact on the surface of carbon-fiber samples.

The problem of increasing of the strength of concretes by means of using suspension based on nanomodified additives with boehmite, graphene and carbon nanotubes is considered. Suspensions were primarily subjected to ultrajet processing. Nano-containing suspensions were studied before and after processing by the indicated method using a Microtrac Bluewave laser analyzer of particle sizes. The analysis provided average particle sizes by quantitative and volume distribution, as well as minimal registered size of particles in the samples. The results of compression strength tests of a batch of concrete samples are presented. It was shown that the use of nanomodified additives leads to an increase in the strength of concrete. It was concluded that investigations must be continued in order to obtain a larger amount of experimental data for statistical processing.

The application of a filler wire in the traditional process of arc surfacing with a flux cored wire in the environment of protective gases is proposed. A flux cored wire of the electrode wire composition is shown to be used as a filler wire. The optimum surfacing parameters, which ensure stable formation of a deposited coating, are determined. The use of a filler wire is found to redistribute the energy balance, to decrease the melting depth of the base metal, and to increase the surfacing speed.

A new technique for examining composites by means if ultrajet diagnostics is considered. The scientific approach is based on imitating material fatigue tests in accelerated mode and evaluating composites for adhesive strength at alternate loads. Ultrajet diagnostics will allow ensuring the performance adequacy of resource strength calculations while designing items from composites by rapidly determining the necessary parameters of physical mechanical properties in the course of their design and process development. A Ti6Al4V titanium alloy powder sample made by selective laser melting is used as an example to show that the geometric parameters of hydroerosion are associated with the surface defects of the sample, its stress–strain state and the in-growth path and direction followed by the scanning laser beam.

The effect of chromium carbide introduced into the charge of a flux cored wire on the structure and properties of the hardfacing deposit is considered. Hardfacing is performed in a shielding gas atmosphere using a flux cored wire. The composition of the flux cored wire is selected so that the iron-based hardfacing deposit alloyed with the Cr–B–Nb–C system is achieved. In hardfacing, chromium carbide decomposes and alloys the hardfacing deposit with chromium and carbon; this leads to the formation of chromium carbides in the hardfacing deposit and to an increase in its hardness. On average, the presence of chromium carbide in the charge of a flux cored wire leads to an increase in the wear resistance of the hardfacing deposit.

A method for the ultrajet diagnostics of products made of composite materials is presented. It makes it possible to simulate, in an accelerated regime, the fatigue tests of materials and to estimate the adhesion strength of the fiber-filler bond under alternating loads. A hydroerosion model of the diagnosed surface under the operation of sequentially conjugate ultrajet actions by various working hydraulic pressures of the ultrajet water applied is considered. The concentration of the functionally significant defects formed at a certain stage in the life cycle of the object of analysis, for example, in the surface layer of the diagnosed product, is taken as a general characteristic of the hydroerosion of the material. Relations that determine the kinetics of formation of an ultrajet hydrocavity on the surface of the object of analysis are obtained. The time spent by the ultrasound on the erosion destruction of the softened layer is determined, which is a new information-diagnostics criterion, since this time characterizes the correlation between the level of action on the surface layer of material and its physical and technological reaction to the ultrajet effect. Results of this research will help one not only to clarify the fracture laws of composites under unsteady loadings, but will also ensure the creation of composite materials with predetermined physical, mechanical, and chemical properties for specific application conditions.

Ultrajet diagnostics is used to analyze bimetallic knives for rotary crushers, and a polymer powder is introduced in a jet to imitate the operating conditions of the equipment. The correlation between the cavern depth formed during ultrajet action on a knife and the geometric parameters of the wear of its cutting edge is shown to be high.

The paper shows that parts of aerospace technology can be subject to abrasive wear and tear. Such exposure results in the failure of critical aerospace parts. The issue of assessing abrasion resistance in the aerospace industry is therefore important. Questions of a choice of a technique of testing of details and knots in the conditions of hydroabrasive influence are considered. It is shown that there is a large number of methods used to assess the abrasion resistance of materials and coatings. Advantages and disadvantages of applied methods are noted. The technique of testing at which the sample is stationary and the water-abrasive jet influences it is offered. Test modes and composition of abrasive and liquid are chosen from real working conditions of the tested parts and assemblies. Setting parameters are liquid composition, abrasive composition and size, liquid pressure on the product, fluid temperature, abrasive flow, distance to the specimen, the angle of attack of the water jet. The design of the plant for implementation of the proposed technique on the basis of sandblasting equipment is proposed. Probation of the developed technique is carried out at testing of samples on which surface there is applied a melted coating. For approbation were chosen coatings resistant to abrasive wear, used for parts working in water-abrasive medium. The tests performed correlate well with known test data for similar products.

The influence of the parameters of feeding and heating of an additional flux-cored electrode during machine hidden arc welding with an additional hot additive on the process is considered. Beads are deposited onto a 10-mm-thick steel (St3sp steel, GOST 380) plate, and the addition conditions, namely, the distance between the flux-cored electrode and the filler wire and the filler wire feed rate, are varied. The filler wire feed rate is found to depend on the electric current used for heating and to be independent of the distance between the point of introduction of the additional hot additive and the main arc. The limiting amount of the filler wire additive at which the transition from a deposited metal to the base metal is not sharp is determined.

The influence of modification by ultradispersed materials on the structure and physicomechanical properties of alloys is considered. Nanostructured boron nitride and aluminum hydroxide monohydrate (boehmite) are chosen as modifying additions to study their influence on the structure formation in a zinc–aluminum–copper antifriction alloy. Scanning electron microscopy and electron-probe microanalysis are used to identify high-hardness phases in the alloy structure. Modifying particles are found to affect the hardness of the alloy, which increases significantly with the number of particles. The strength of the alloy depends on both the number and the size of introduced particles, and powders with small grain sizes are more effective to increase the strength of the alloy. Moreover, silicon carbide is shown to exert a stronger effect on the strength of silumins than alumina does.

We substantiate the recommendations for improving the efficiency of hydro- and hydroabrasive cutting of the honeycomb structures that are widely used in aircraft and rockets, obtained by numerical solving of the spatial dynamic problem with allowance for the physico-mechanical and kinematic parameters of a high-speed jet, the physico-mechanical and structural parameters of the treated honeycomb structure, and the parameters of the technological treatment (feeding and the impact angle of the jet with the face surface of the blanks). A physico-mathematical model and a method of numerical analysis of the process have been developed. The influence of the above parameters on the quality of the surfaces of the treated blanks is illustrated. The results of the calculations are compared with the experimental data.

X-ray diffraction analysis methods and their application in studying materials, including nanomaterials, are reviewed. The physical phenomena served as the basis for these methods, the designs of the experimental apparatuses to be used to record X-ray diffraction patterns, and the algorithms of their analysis are considered. The advantages and disadvantages of each method are described, and advanced methods for investigating nanomaterials are proposed.

An ultra-jet diagnosis method for studying the effect of heat treatment regimes on material structure is suggested. Results of experimental studies of hardness, depth of hydraulic cavities, and microstructure of alloy steel specimens after various heat treatment regimes are provided.

The SiO2–TiO2 aerogel composites used in the heat insulation of a hydrothermal reactor and the method of their fabrication using a liquid glass technology are analyzed. The process of fabrication of the composite material includes the following stages: the ion exchange of sodium liquid glass with the formation of silica hydrosol; the concentration of hydrosol; the formation of hydrogel and its maturing; the formation of alcogel of an SiO2–TiO2 composite material; surface modification; subcritical drying of alcogel with the formation of SiO2–TiO2 composite ambigel; and its heat treatment, granulation, and classification. The influence of infrared absorber (titanium dioxide) and the temperature of heat treatment of an SiO2–TiO2 aerogel composite material on its structural and thermal characteristics is studied.

Changes in the dielectric constant and dielectric loss tangent of water that was first subjected to impact loads under the action of an alternating magnetic field were determined quantitatively using a micro-wave system, which allows solution of the inverse problem. The results of measurements of the optical spectrum of water in the “transmission” mode, which was subjected to a shock load, in comparison with the optical spectrum of distilled water, are described.