In modern industry, the demand for efficient, rapid, and cost-effective production of complex-shaped and large-sized metal parts is steadily increasing. To meet this need, additive manufacturing technologies - particularly WAAM (Wire Arc Additive Manufacturing) - are being widely adopted. However, one of the major drawbacks of WAAM is the frequent occurrence of structural defects such as interlayer boundaries, anisotropy, microcracks, and porosity. In this context, the present study explores the potential for improving the structural quality of WAAM-fabricated parts by integrating MIG welding with interlayer rolling applied immediately after each deposited layer. The aim was to refine grain size and increase the density and homogeneity of the structure by subjecting the freshly deposited layer to plastic deformation. Samples made from ER70S-6 steel were analyzed using a Leica DMI8 optical microscope, and the structural effects of rolling were evaluated at both the macro and microstructural levels. The results revealed that in rolled samples, interlayer boundaries were eliminated, porosity and anisotropic features were significantly reduced, and a fine and homogeneous grain structure was formed. These findings confirm that interlayer rolling can be an effective tool to minimize structural imperfections in WAAM and enhance the final product quality. Future improvements may include the application of multidirectional pressure and numerical modeling of the deformation process for further optimization.

https://doi.org/10.48081/BEQG7389

2025

Issue 4

This article presents the studies of the physicochemical properties of granules obtained by granulation of aluminum slags. During the studies, the granules were subjected to hardening firing at high temperatures to understand the chemistry of the process. To study the physicochemical properties, samples of granules obtained from aluminum slags were prepared, which were subjected to microanalysis by scanning electron microscopy, X-ray phase analysis and derivatographic studies. The studies showed that the main phases in the granules are Al2MgO4, Al5,65Mg2,39O10Si1,45, MgO3Si, Al2,4O4,8Si0,6, Al2O3. The main part of the studied granules is represented by spinel, mullite, aluminum oxide, sapphirine. Moreover, spinels in the phase composition of sample №. 1 amounted to 25.4%, sapphirine 26.0%, aluminum oxides 25% and mullite accounts for 11.7 5, the rest is MgO3Si (11.9%). The theoretical temperature of the reduction of the main element of silicon by carbon is 1669 °C, and the complete destruction of mullite is achieved above 1500 °C. Therefore, granules obtained from aluminum slags are quite suitable for use as a batch in the production of ferrosilicon with aluminum. Keywords: Aluminum slag, granules, aluminum oxide, high-temperature firing, derivatogram.

10.48081/MMQL5744

2025

Issue 4

The problem of secondary processing of fine industrial waste remains a pressing issue for many metallurgical enterprises due to its impact on production efficiency and the environmental situation in the surrounding area. This is especially relevant for foundries, where coarse scrap—such as defective castings and sprues—is reused directly, while fine-grained waste from mechanical processing is typically discarded. A significant proportion of such waste is formed during the machining of high-carbon chromium steel ShH15, widely used in the manufacture of bearing parts. The operations of grinding, turning, and polishing result in the formation of fine powder-like particles that are difficult to recycle due to oxidation and contamination with lubricants and cooling fluids. An effective way to utilize this material is through the cold briquetting method, which consists of mixing the steel dust with binders and compacting it under pressure into briquettes suitable for melting in induction or arc furnaces. This approach not only reduces the volume of waste sent to landfills but also returns valuable alloying components to the production cycle, improving resource efficiency. Additionally, briquetting helps reduce the environmental burden and contributes to the development of closed-loop metallurgical technologies. When properly formulated, the resulting briquettes exhibit sufficient strength, low porosity, and compatibility with melting processes. Optimized compositions allow the use of briquettes as cost-effective charge material, promoting sustainable steel production practices [1;2;3].

10.48081/NFBN7376

2025

Issue 4

Optimization of parameters of dry high-gradient magnetic separation of technogenic manganese tailings of Zhezda concentrating plant (Mn - 10.6%, Fe - 2.7%, SiO ₂ - 59.8%) was investigated. Mineralogical analysis showed that manganese is concentrated mainly in weakly magnetic oxide phases (brownite, psilomelane), which justifies the use of powerful magnetic fields. Laboratory tests were carried out on the PC-V 12/10-12.018-2012 unit at inductions of 0.5-1.1 T according to the three-stage scheme. As a result of the main separation (1.1 T) and two purges (0.7 and 0.5 T), the manganese content in the final magnetic concentrate reached 29.07%, having increased by about three times compared to the initial one; total recovery of Mn was 66.82% and concentrate yield was 24.34%. The share of silicon oxide decreased from 59.8% to 33%, which significantly increased the metallurgical quality of the concentrate. Proposed technology of dry high-intensity magnetic separation ensures efficient processing of technogenic manganese wastes and production of commercial concentrate suitable for metallurgical processing.

10.48081/GDOV2218

2025

Issue 4

Amid the growing importance of the Trans-Caspian International Transport Route (TITR), the modernization of train interval control systems (TICS) on Kazakhstan's railway network has become particularly relevant. This article presents a comprehensive analysis of existing TICS types, including semi-automatic blocking, various forms of automatic blocking (coded, impulse-wire, and automatic locomotive signaling as an independent system), as well as promising radio-based interval control systems. Based on official statistics and data visualizations, the study highlights the predominance of outdated technologies on key transit routes, including segments of the TITR. Several critical issues have been identified, such as the high proportion of single-track sections and the continued use of semi-automatic blocking, both of which limit line capacity. The study emphasizes the strategic importance of transitioning to digital traffic control and radio-based TICS. Special attention is given to national railway modernization policy, including initiatives to expand and construct new railway lines. The findings presented in the article provide justification for prioritizing the technical upgrade of segments critical to transit flows and may serve as a foundation for the development of digital transformation roadmaps for the railway sector.

10.48081/COBQ8854

2025

Issue 4

This paper presents a study of how the cooling rate affects the microstructure and performance of high-chromium cast iron of grade ChKh16, alloyed with carbide-forming elements. The experimental alloy was modified with 1.5 wt.% of niobium and 0.7 wt.% of vanadium and titanium each. The melt was cast into three types of molds: metal, shell, and sand-clay, which provided different cooling rates during solidification. Microstructural analysis showed that a lower cooling rate leads to the formation of complex Me₁₋ₓC-type carbides with a higher volume fraction and more uniform distribution. Samples cast into sand-clay molds showed the most developed carbide phase, resulting in better mechanical properties. In particular, hardness increased by 17 %, and wear resistance improved by almost 30 %. This effect is associated with the presence of a relatively soft austenitic matrix and evenly distributed hard carbide inclusions. In contrast, rapid cooling in metal molds limited carbide formation, which reduced hardness and wear resistance. The study shows that for carbide-forming elements to work effectively, a cooling rate close to equilibrium is required. This ensures the stable formation of carbide phases and improves the durability of the alloy. These results are useful for the development of wear-resistant cast irons and for improving industrial casting technologies.

10.48081/NPXB8484

2025

Issue 4

This article presents the results of numerical simulation of the stress-strain state (VAT) of structural elements of an airfield baggage trolley (BAT), conducted using the finite element method (FEM). Two typical loading scenarios are considered: the vertical load that occurs when the load is placed on the platform, and the horizontal load typical for towing operations. To carry out the analysis, a finite element (CE) model of a trolley was built using the SolidWorks Simulation software package, which has a wide range of capabilities for modeling complex mechanical systems. As part of the simulation, stress and displacement fields were determined in various sections of the structure, which allowed for a comprehensive assessment of the strength and stiffness characteristics of the BAT. Analysis of the simulation results showed that the maximum values of stresses and displacements do not exceed the maximum permissible values for structural steel used in the manufacture of trolleys. This indicates the high reliability and operational suitability of the BAT design, which is confirmed by the results of the strength calculation. In addition, the article discusses in detail an improved braking device designed to ensure reliable fixation of the trolley in both the raised and lowered position of the drawbar. This solution is an important element in improving the safety of BAT operation and minimizing the risks of emergency situations. Thus, the numerical modeling and VAT analysis of the structural elements of the baggage airfield trolley allowed us to confirm its compliance with modern requirements for reliability and operational safety, as well as to identify potential ways to improve the efficiency and safety of operation of this equipment.

https://doi.org/10.48081/QQDN4359

2025

Issue 4

This paper presents the results of a comprehensive study of multilayer (TiAlSiY)N/CrN coatings subjected to gold (Au⁻) ion implantation at an energy of 60 keV and a fluence of 1×10¹⁷ ions/cm². The aim of the study was to investigate the microstructural changes and elemental redistribution induced by ion implantation in the structure and composition of the coatings. Analytical techniques included grazing incidence X-ray diffraction (GIXRD), high-resolution transmission electron microscopy (HRTEM), scanning transmission electron microscopy (STEM), secondary ion mass spectrometry (SIMS), and ion range modeling using the SRIM code. The results showed that ion implantation led to the formation of an amorphous surface layer up to 20 nm thick, a reduction in crystallite size from ~8 nm to ~4–5 nm, and interlayer mixing accompanied by distortion of layer boundaries. SIMS and RBS analysis revealed selective nitrogen sputtering, redistribution of alloying elements (Si, Y), and gold ion penetration to a depth of approximately 20 nm. These findings demonstrate significant changes in the phase and elemental state of the coatings and may be used in the development of functional nanostructured coatings designed for operation under radiation exposure and aggressive environments.

10.48081/SFBX2679

2025

Issue 4

The aim of this study is to investigate the effectiveness of the Deep Deterministic Policy Gradient (DDPG) reinforcement learning algorithm for generating and optimizing agent trajectories in tasks with continuous control spaces. The research focuses on demonstrating the capabilities of DDPG under a limited number of episodes and in complex environments with obstacles and multiple target points. Particular attention is given to the design of the reward function, which accounts for the distance to the target, obstacle avoidance, and successful goal achievement, as well as the visualization of the generated trajectories. It is shown that the application of the DDPG algorithm enables the agent to adaptively learn and successfully reach both single and multiple targets while forming efficient trajectories. The agent exhibits stable behavior in response to changes in task conditions and demonstrates a high ability to avoid obstacles. Despite the limited number of episodes, the agent is able to consistently reach goals along near-optimal paths in most cases. The results confirm the potential of using DDPG in trajectory planning and control tasks, including applications in robotics. Further research may focus on expanding the environment, increasing the number of targets, and introducing more complex reward functions.

https://doi.org/10.48081/SMDB4537

2025

Issue 4

This article presents a structural diagram of a closed-loop electric drive system frequency converter - brushless motor of an electric vehicle. A mathematical description of the dynamics of the closed-loop system "FC-BLDC" is presented. A program for synthesizing the parameters of a nonlinear correcting device of the system is given. Solving problems related to determining the parameters of a closed nonlinear system of the electric drive "FC-BLDC" requires the use of various mathematical methods. In the program of parameters synthesis, nonlinear correcting device the gradient-free scanning method, numerical Runge-Kutta method for solving differential equations of dynamics of closed system "FC-BLDC" and algorithm of calculation of partial derivatives of function R. Bellman are applied. The graph of transient processes of speed and torque of brushless motor is given. The graph of transient processes of the speed and torque of a valve motor is given. A special functional program for calculating differential equations is written. The algorithm for estimating the parameters of the model, which describes the process of changing the speed and torque in measurements, is considered in detail. It is shown how, knowing the logic of constructing an algorithm, it can be modified to suit changing conditions and obtain the required result (an estimate of the model parameters). The synthesis of parameters of a system of a given structure and the synthesis of corrective devices of the system according to given quality indicators are considered as an engineering task, which is reduced to such a construction of automatic control systems, which ensures the full-fillment of technical requirements, and also in the engineering synthesis of automatic control systems the following are ensured: the necessary precision and positive nature of the transition processes, in which the best of many possible solutions is finally selected from the point of view of existing specific conditions.

10.48081/DGVE7126

2025

Issue 4