№4 2022
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1
Examines the study of the effect of deformation and subsequent heat treatment on the structure of single-crystal samples from a heat-resistant intermetallic alloy based on the Ni3Al compound. It is shown that at a degree of deformation (upsetting in a closed container) ≤40 %, no cracks are formed in the structure of the material under study. Subsequent thermal annealing after deformation promotes the process of recrystallization and the formation of a grain structure in deformed samples of an intermetallic alloy based on the Ni3Al compound.
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2
Describes the results of the work performed on the development of technology for the manufacturing of forgings of disk made of heat-resistant nickel alloys by isothermal deformation on air using computer modeling in the QForm software package. The stress-strain state of die tooling was calculated and the technology for producing disk forgings for welded shafts of the TK32 compressor was developed. Information on the of introduction of the developed technology into serial production are presented.
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3
The production of polymer composite materials (PCM) in the twenties and in the future until 2030 will continue to grow, despite the pandemic and other obstacles of modern reality. And although the designs are becoming more integral, manufacturers are still faced with the task of choosing the type of machining. The use of machining with diamond wheels on water-cooled machines allows cutting various composites (fiberglass, carbon fiber, organoplastics and hybrid materials) with the required precision and quality.
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4
High-temperature influence on composite material based on molybdenum hardened with dispersed particles of Al2O3 oxide structure and phase composititon is considered. Temperature was change in the range from 1300 to 2050 °C. With scanning electron microscopy application microstructure analysis is carried out, by X-ray microanalysis means local element composition is defined, also by diffraction analysis means samples surface phase composition in an initial condition and after impact is investigated.
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5
Using the method of transmission optical microscopy in polarized light, changes in the internal structure of various oxide ceramic fibers under the influence of high-temperature heats were investigated. Complete restructuring of the structure of all examined fibers in the process of high-temperature exposure was revealed. Significant differences were established during recrystallization between fibers of different types. Mullite compositions showed stabilization of the recrystallization structure at the stage of formation of moderately large grains separated by stable large-angle (up to 90°) borders.
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6
In this work, we investigated the main physical and mechanical properties of VPZ-24 syntactic foam based on a cyanate ester polymer base with the addition of hollow glass microspheres as a filler. Syntactic foam VPZ-24 is intended for filling sections of multilayer honeycomb heat-loaded structures. The results of the study of the microstructure of syntactic foam are shown. The influence of the effect of elevated temperature on the values of the ultimate strength in compression of a syntactic foam is shown. It was found that the maximum service temperature of syntactic foam VPZ-24 is 320 °C.
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7
A method for increasing the adhesive interaction at the interface between a carbon fiber reinforcing filler and a polymer matrix in polymer composite materials by modifying the filler surface by electrochemical treatment is considered. The methods used to characterize the surface of the origin and modified fibers are listed. The features of the electrochemical oxidation process of carbon fibers are shown. The main advantages and disadvantages of this modification method are given. An overview of the results of studies of electrochemical oxidation of carbon reinforcing filler use to improve the mechanical characteristics of carbon plastics is given.
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8
The article is devoted to the creation of radio-absorbing polymer composite materials of a dielectric type of reduced density. The main characteristics of a number of developed domestic and foreign foamed radio-absorbing materials are given, the technologies for their production, the scope of application are described and the features of radio-absorbing materials for use in anechoic camera are considered. The characteristics of the reduced density radio-absorbing materials developed at the Kurchatov Institute Research Center – VIAM are given.
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9
Considers the question of the influence on the structure of the PEO coating of the time ratio of exposure to the polarizing voltage in the anodic and cathodic half-periods during the oxidation process in a silicate-phosphate electrolyte. A linear dependence of the time of cathodic polarization and the thickness of the coating formed on a cast magnesium alloy in a silicate-phosphate electrolyte has been revealed. When using anodic pulses of short duration, the coating has numerous defects in the form of pores, which negatively affects the protective properties.
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10
A method is proposed for the determination of scandium, yttrium, cerium, lanthanum, neodymium, and praseodymium by inductively coupled plasma atomic emission spectrometry in aluminum alloys. Analytical REM lines free from significant spectral overlaps are selected. The selection of the sample preparation method was carried out, namely, dissolution in a mixture of hydrochloric and nitric acids. The accuracy indicator of the developed technique is not more than 4% rel. for the content of rare-earth metals from 0.05 to 6 wt. %, which fully ensures the control of the content of rare-earth metals in products made of aluminum alloys.
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11
Was investigated by the effect of using yttrium on the properties of the sintered Magnets Nd–Dy–Y–Fe–Co–B. It is shown that the coercive force on the magnetization and induction is decreased with an increase in the content of yttrium. The magnitude of the rectangulation of the clarification curve slightly increases. The value of residual induction and the magnetization of saturation changes not significantly, but tend to increase with the content of yttria. Thus yttrium is not desirable impurity in thermostable magnets for navigation instruments.
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12Part 1. Investigation of corrosion-mechanical destruction of steels
Considers the main stages of the process of formation of protective passive films on steel in a hydrogen sulfide-containing environment and the destruction of metal materials under the simultaneous influence of a corrosive environment and mechanical loads. The main theories and practical results of determining changes in the mechanical characteristics of steel under the influence of a corrosive environment and mechanical loads are presented. The values of relative constriction, elongation, and tensile strength at slow stretching are accepted as the main criteria for the corrosion destruction of materials.
