This study investigates the effect of mechanical synthesis duration on the morphological and structural characteristics of tungsten carbide (WC)-based composite powders alloyed with iron (Fe) and nickel (Ni). Four compositions were synthesized: WC88–Fe12, WC95–Fe5, WC88–Ni12, and WC95–Ni5. Mechanical activation was performed in an argon atmosphere at a rotation speed of 500 rpm for 1, 2, and 4 hours. Particle size distribution analysis was conducted, and the median particle diameter (D₅₀) was determined to assess the evolution of particle size with increasing milling time. It was found that prolonged mechanical treatment led to particle coarsening, especially in systems with high WC content (95 wt.%), where after 4 hours of milling, noticeable powder agglomeration and adhesion to the container walls and grinding balls occurred. The particle morphology was examined using scanning electron microscopy (SEM), and the results were consistent with the granulometric data. At the early stages of mechanical synthesis, efficient particle fragmentation was observed; however, with longer milling durations, particle agglomeration occurred. Fine particles began to stick together, forming loose agglomerates, leading to an increase in aggregate size due to mechanochemical interactions and interparticle adhesion. X-ray diffraction (XRD) analysis revealed a decrease in peak intensity and broadening of the diffraction lines corresponding to WC and metallic phases, indicating a reduction in crystallinity, crystallite size refinement, and an increase in lattice defects. The obtained results made it possible to determine the optimal conditions of mechanical synthesis for producing homogeneous powder mixtures suitable for subsequent sintering.

https://doi.org/10.48081/GMBM5273

2025

Issue 3

This article presents a study of the possibility of using additive technology methods in the manufacture of hydraulic machine parts, in particular gear pumps (GP). As a result of the analysis of repair production facilities of the subjects of the agro-industrial complex of the Republic of Kazakhstan (AIC RK), it was revealed that GP parts are most often sent for repair and restoration. It has been established that the main causes of pump failures are the opening of the contact of the gear teeth during pump operation, poor assembly, wear of bushing parts, thrust bearings, gear teeth, etc. It was also revealed that there is a major problem in the conditions of repair production of service entities of the agro-industrial complex of the Republic of Kazakhstan, associated with the lack of necessary technological equipment, technological tooling and tools when performing repair and restoration work. The maximum stress reaches 18.45 MPa, which is within the permissible limits for plastics used in 3D printing. The study was carried out within the framework of the grant topic funded by the Science Committee of the Ministry of Science and Higher Education of the Republic of Kazakhstan AP23489364 "Use of additive technologies in the repair of agricultural machinery with process optimization through modeling and experimental research."

https://doi.org/10.48081/VFQK8410

2025

Issue 3

In the conditions of modern manufacturing industry, there is an active use of difficult-to-machine materials with high strength, heat resistance and corrosion resistance. However, their mechanical processing is accompanied by increased tool wear, decreased productivity and difficulties in ensuring the required surface quality [1, pp. 71-73]. In this regard, modern processing methods, in particular high-speed milling, are of increasing interest. This article provides an overview of current methods of processing hard-to-process materials used in world practice, and identifies the features of processing hard-to-process materials. Experimental studies have been carried out, in which the main attention is paid to the effect of high-speed milling on the properties of the surface layer of processed materials. Three types of difficult-to-process materials were used as objects of research: titanium VT-1, heat-resistant steel 20X23H18 and austenitic corrosion-resistant steel 10X17H13M2T. The analysis of the hardness and roughness parameters of the treated surface showed the advantages of high-speed processing in providing more stable characteristics. The experimental results confirmed the effectiveness of high-speed processing. The presented data can be used to optimize processing modes in mechanical engineering and other high-tech industries. Thus, this research is relevant and in demand in the context of the development of modern machine-building industries focused on improving the processing efficiency and product quality when working with difficult-to-process materials.

https://doi.org/10.48081/SSHV6727

2025

Issue 3

The processing of gold-copper ores with high copper and gold content embedded in sul-fide minerals using cyanide solutions is associated with a number of difficulties. Copper, when reacting with cyanide, causes its increased consumption, and the embedding of gold in sulfide minerals causes gold losses with tailings. Therefore, selecting the optimal leaching conditions is necessary for the rational use of reagents, which leads to a reduction in the cost of hydrometallurgical processes for cyanide leaching of gold-copper ores and a reduction in environmental risks. The paper investigates the possibility of processing gold-copper ore with a high copper content and gold incorporated into sulfide minerals (pyrite, chalcopyrite). The aim of the work is to establish the optimal parameters for cyanide leaching by conducting tests in bottle agitators. As a result of the experiments, it was found that as the degree of ore grinding increases, gold extraction increases and cyanide consumption decreases slightly. The addition of coal during leaching significantly increases gold recovery, up to 7%. It was noted that high sodium cyanide consumption cannot be reduced without a significant decrease in gold recovery. Au ≈ 20% reduction in sodium cyanide consumption also reduces gold recovery by ≈ 20%. A laboratory-industrial experiment showed that after 16 hours of ore leaching, 85.8% of the gold is transferred into solution, and after 18 hours, 86.7%. Further prolongation of the process does not increase the gold recovery rate.

https://doi.org/10.48081/WDQW8381

2025

Issue 3

The article reports the outcomes of a practical study into the cold briquetting of powdered residue ShH15 steel cutting debris. Through the analysis of compaction behavior, three sequential stages were identified: an initial elastic compression phase, followed by fragmentation and densification, and concluding with plastic consolidation forming a solid briquette structure. The pressing procedure was conducted at ambient temperature using equipment equipped with an adjustable matrix configuration. Resultant compacts achieved relative densities in the range of 90–91% of theoretical values under forces up to 850 kN and corresponding pressures of 450–500 MPa. The specific energy input required for material deformation was estimated at 2.6–2.8 kJ/g. The results validate the feasibility of utilizing unprocessed steel waste through energy-efficient compaction, eliminating the need for thermal pretreatment.In addition to improving material utilization efficiency, the proposed method supports broader sustainability goals by enabling low-cost, low-energy recycling of industrial residues. These findings may serve as a foundation for scaling cold briquetting processes to industrial applications, especially in contexts where thermal methods are economically or environmentally impractical.

https://doi.org/10.48081/WMDV7314

2025

Issue 3

This article analyzed the principles of operation of semi-automatic blocking, automatic blocking and radio blocking systems used in order to ensure the safety and throughput of train traffic on the railway network. The structural and functional features of each system were described, the mechanisms of interval regulation of movement and the logic of train displacement were studied using mathematical modeling methods. In the course of the study, a quantitative analysis of the throughput of each system was carried out, taking into account such basic parameters as the length of the interval, the speed of smooth movement of trains, the braking path, the safe interval and the time of action of the duty. The results of the model simulation clearly demonstrated the technical capabilities and limitations of each system. According to calculations in typical conditions, the throughput indicators were determined in the semi – automatic blocking system at the level of about 9.6 trains/hour, in automatic blocking – 21.9 trains/hour, and in radio blocking-60 trains/hour. These results showed that the relevant systems directly depend on the accuracy of interval control, methods for measuring distances between trains, and the level of signaling devices. The relative efficiency of the systems has been determined using diagrams and other visual tools, which makes it possible to create an engineering justification in the process of making a technical decision. In addition, the results of the study prove the relevance of the introduction of digital control systems in the modern railway network, in particular radio blocking technologies, and its strategic advantages in transport logistics.

https://doi.org/10.48081/PVCX2453

2025

Issue 3

The article presents the results of a study on the processing of silicon production waste with the development of a composite lime binder for dry building plaster mixtures intended for restoration and finishing works. The article examines the potential of using metallurgical wastes, primarily microsilica, as an active mineral additive for dry building mixtures on a lime-cement basis. Microsilica, being a by-product in the production of metallic silicon, has a high pozzolanic activity and is of interest as a component that contributes to increasing the strength, water-repellent and adhesive properties of plaster compositions. In order to obtain an effective composition for restoration and finishing work, laboratory studies were carried out, including the selection of compositions, the assessment of physical and mechanical characteristics and the analysis of environmental aspects. Metakaolin and carbonate mineral powder were used as additional modifiers, which made it possible to achieve a comprehensive improvement in the properties of materials. The results obtained showed that the inclusion of microsilica in the amount of 10% of the binder weight provides a strength increase of up to 35% compared to the control composition. In addition, a decrease in water absorption and an increase in the resistance of solutions to the external environment were revealed. The work confirms the technical, economic and environmental feasibility of reusing microsilica in the production of dry building mixtures, which contributes to reducing waste and increasing the sustainability of the construction industry.

https://doi.org/10.48081/THTE8411

2025

Issue 3

This paper addresses the problem of speed control for an electromechanical drive with elastic coupling employed in a hybrid crank press possessing two degrees of freedom. Such presses integrate the kinematic structure of a seven-link mechanism with high-precision servo drives, enabling the implementation of adaptive slider motion laws that meet specific technological requirements and yield an optimal stroke profile. To describe the dynamics of the electromechanical subsystem, a split inertia model is adopted that captures the elastic properties of the shaft linking the drive to the mechanism’s actuating member. A stat feedback based controller-synthesis approach is proposed, ensuring stable and accurate trajectory tracking even under varying load conditions. Comprehensive numerical simulations and experimental studies on a laboratory test bench confirm the effectiveness of the developed control algorithm. Particular emphasis is placed on compensating elastic oscillations and maintaining robustness against parametric disturbances. The findings can be applied to the design of modern adaptive control systems for high precision servo presses with mechanical transmissions operating under variable technological loads.

https://doi.org/10.48081/WPKV1070

2025

Issue 3

The subject of this study was 30KhGS steel produced using briquettes fabricated from fine-dispersed dust (FDD) generated during ferroalloy production. Steel samples manufactured with FS50-7 briquettes served as the reference. The experimental briquettes were composed of fine-dispersed ferrosilicon dust combined with iron ore concentrate, with bentonite clay acting as a binder. The chemical composition, mechanical properties and microstructure of the 30KhGS steel produced using the experimental briquettes were thoroughly examined. Mechanical testing, hardness measurements, and microstructural analysis were conducted to assess the performance characteristics of the resulting steel. The results demonstrated that deoxidation using the experimental briquettes yielded steel whose chemical composition and mechanical properties conformed to the GOST standards for this grade. Additionally, the use of these briquettes enhanced resource efficiency, lowered production costs, and reduced the environmental impact of the process. Furthermore, the briquetted material developed through this method shows potential for implementation in large-scale industrial metallurgical applications. Overall, the findings highlight a promising approach for sustainable steel production through the recycling of ferroalloy industry waste.

https://doi.org/10.48081/DUYX2087

2025

Issue 3

In this article, research and quality control of contact butt welded joints of bars of various diameters and made of various materials are carried out. The analysis of scientific research carried out by foreign scientists has been carried out, the results of which have shown that the method of contact butt welding is widely used to connect homogeneous as well as heterogeneous metal materials. The results of the study showed that contact butt welding, in particular reflow welding, accounts for more than 40% of the total volume of contact welding applications. It is revealed that there is a need to increase the efficiency and technological feasibility of using contact butt welding in production, in particular in machine-building and construction enterprises. To this end, a series of experimental studies were conducted on the connection of various materials by contact butt welding in the laboratory of the Institute of International Welding at the Karaganda Technical University named after A. Saginov. The quality control of the contact butt welded joint was carried out using a mirror shadow method. The stages of joint formation during contact butt welding by reflow were also considered. As well as a typical cyclogram of the reflow butt welding process. The results of the mirror-shadow inspection of welded joints obtained by contact butt welding showed that more than 95% of the tested samples have no defects in the welds.

https://doi.org/10.48081/OCGR8081

2025

Issue 3