International Scientific Journals
of Scientific Technical Union of Mechanical Engineering "Industry 4.0"

This study evaluates the applicability of Powder Forging for producing hypercompositional structures from heat-resistant powders based on Inconel 625, ZhS6U, and CoCrAlY alloys. One-step forging and triple forging at 1150 °C were examined to determine their influence on densification, prior particle boundary elimination, microstructural evolution, and high-temperature mechanical behaviour. Triple forging markedly improved interparticle bonding, reduced structural defects, and enabled the formation of dense composite architectures with statistically distributed constituents. The Inconel 625-ZhS6U and Inconel 625-CoCrAlY systems demonstrated high yield strength over a broad temperature range and exhibited anomalous strengthening at elevated temperatures, attributed to dynamic strain aging and phase redistribution. The results confirm that Powder Forging is a promising thermomechanical route for designing advanced heat-resistant powder composites for aerospace hot-section applications.

Current construction practice often implies the need to carry out specific actions related to the specification of current operating characteristics of existing and operated in different periods in different ways fibre-reinforced industrial concrete internal floorings and external pavements. Such problems are most often related to a planned change in the operating load, or to estimate their service life in the future. In this regard, specific parameters of a system approach proposed by the author are specified below, including the necessary preliminary field, laboratory and analytical activities related to establishing the current strength-deformation and other essential characteristics of existing industrial concrete floorings and pavements, as follows: concrete cross-section thickness, concrete strengthdeformation characteristics, type and amount of reinforcement used (including fibres), deformation characteristics of the crushed-stone base – according to the dynamic penetration in number of test points, static calculations for the new load conditions, restoring their integrity after sampling, etc. Given the lack of any normative documents on the subject, the proposed systematic approach to the assessment of the residual operational resource of existing fibre-reinforced industrial concrete floorings/pavements is of important methodological importance and fully corresponds to the needs of real construction practice. Its practical use has been approved by the author through a number of successfully conducted systematic expert procedures at a number of sites in the country and abroad.

Mechanical tests of 5- and 6-component high-entropy alloys, which were obtained for the first time by the method of hot forging, were carried out. The test results showed a fairly high hardness and strength of the obtained alloys. The TiCrFeNiC alloy (without annealing) has the highest mechanical properties. Its high strength is due to solid-solution hardening, as well as the formation of carbides in situ. Fractographic studies showed mostly quasi-brittle destruction of alloy samples.

The article presents the results of studies on the study of the physical and mechanical characteristics of polymeric materials modified with mechanically activated particles. It is shown that the use of mechanically activated nanosized particles makes it possible to achieve a significant effect of increasing operational characteristics at relatively low degrees of modification of 0.05% wt. – 3% wt. The use of modifiers at such concentrations in polymer matrices makes it possible to preserve the basic technology for the processing of polymeric materials and equipment in the manufacture of composite materials on a polymer matrix.

The research of the technology of obtaining new copper-ferrochrome composite material has been done. The results of its structure and properties analysis are presented. The material structure consists of the copper base, non-dissolved coarse inclusions of ferrochrome, diffused zones, forming around these inclusions and phases, having formed in the place of completely dissolved inclusions of ferrochrome fine particles. The material has good mechanical properties and a high wear resistance due to the formed solid solutions of the carbides in the copper.

In this work, the method of backscattered electron diffraction (EBSD) and transmission electron microscopy (TEM) was used for microstructural analysis of the improved VT8M-1 alloy (Ti-5.7 Al-3.8 Mo-1.2 Zr-1.3 Sn) subjected to equal-channel angular pressing (ECAP) and rotary forging (RF). It was found that the process of globularization induced during deformation processing is regulated by the conventional boundary-splitting mechanism. It was shown that an orientation relation is established between the spheroidized a – and bphases. This result is achieved due to the high activity of dislocation sliding at the boundary of the a-and b-phases. The thermal stability of the VT8M-1 alloy with an ultrafine-grained (UFG) structure is s -term (up to 500 hours) annealing the UFG structure is thermally stable. The mechanical properties and the effect of annealing on the microstructure are discussed. It is shown that particles of the Ti-Zr-Si system are isolated at the interphase boundaries.

The UFG structure in the VT8M-1 alloy was formed by rotary swaging (RS). Experimental forged billets of ultrafine-grained structure (UFG) were obtained by isothermal die forging (IDF). The structural parameters and the homogeneity of the UFG structure were analyzed. Microstructure and mechanical properties of experimental workpieces of the ultrafine-grained VT8M-1 alloy produced by isothermal die forging was analyzed. The relationship between the microstructure and mechanical properties of the forged workpieces of the UFG VT8M-1 alloy is discussed.

The work is devoted to the development of a solid-phase technology for obtaining high-temperature layered composites from Nballoys. The following are presented: one of the options for the formation of the initial multilayer package and its diffusion welding (1), the microstructure of the obtained composites (2) and the results of testing composites (3) for strength at room temperature and temperatures up to 1350°C, taking into account the structure anisotropy, crack resistance and tests for creep with two options for processing the obtained experimental data.

The microstructure and characteristics of the heat resistance of layered composites of Nb–V alloys and intermetallic compounds with aluminum are presented. The composites obtained by diffusion welding under pressure of packages of aluminum foils and foils of niobium alloys with 5, 10, and 15 at. % vanadium had structures representing an alternation of viscous-plastic layers and reinforcing layers of aluminides. The composites were characterized by a viscous-plastic nature of fracture and higher values of strength at room temperature and temperatures up to 1300°C, in comparison with composites without vanadium.

The article presents the results of a study of the influence of technological parameters of FDM-printing of samples based on aliphatic polyamide on the deformation and strength characteristics of products based on it. The anomalous nature of the increase in the tensile strength during the destruction of samples obtained by increasing the print speed is shown. A decrease in the strength of the samples was noted with an increase in the number of simultaneously printed products. The main factor determining the strength characteristics of FDM products is interlayer autohesion. The need for the use of materials science solutions that contribute to an increase in interlayer interaction in products obtained by layer-by-layer deposition is indicated.

In this paper, we consider the theoretical foundations of the synthesis of ceramic materials from natural aluminosilicates with the addition of technogenic materials (lead and copper slag) using powder metallurgy methods. The characteristics of the feedstock, properties are presented, the geographical deposits of natural components are shown. The possibility of obtaining pelletized, granular, and block ceramic materials based on natural and technogenic sorbents of Kazakhstan is shown by powder metallurgy methods.

The paper considers the impact of functionalized nanosized carbon particles on the physicomechanical characteristics of composite materials based on polyamides. The concentration of the modifier varied both in the field of “doping” concentrations and in the field of concentrations used in the industrial production of nanocomposite materials based on polymer matrices. It was found that the use of cryogenic treatment of the initial polyamide leads to an increase in physical and mechanical characteristics. The introduction of nanodispersed particles in the field of “doping” concentrations increases the strength and hardness of the developed compositions based on a polyamide matrix.