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

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

Pyrometallurgical processing of copper produces large amounts of industrial waste, namely slag and tailings. Due to the significant amount of valuable components such as zinc and iron in copper slag, slag processing is a pressing issue. Traditionally, pyrometallurgical reprocessing is used, for example, roasting, which produces slag containing copper, zinc, and other metals. Traditionally, pyrometallurgical processing is used, such as roasting, which produces slag containing copper, zinc, and other metals, which is then stored. Copper slag has a complex mineralogy due to formations resulting from thermal processing, therefore the use of hydrometallurgical processing is the most optimal option. The stage of determining the material composition and characteristics of man-made raw materials – dump slag – is of great importance, as it determines the further selection of the optimal hydrometallurgical processing mode, namely the choice of reagent, process duration, and leaching temperature for more efficient copper extraction. The above factors influence the process, since the degree of copper-containing slag exposure directly depends on the physical characteristics of the slag, thereby determining the further processing. As a result of the conducted studies it was established that the total copper content in the slag of the Irtysh Copper Smelter is 0.52%, zinc 2.9%, and iron 33.90%. The average chemical composition of the slag samples (%): FeO≈43%; SiO2≈34%; Al2O3≈6%; CaO≈6%; MgO≈1.5%.

10.48081/UEXW3240

2025

Issue 4

The engine is one of the most important and complex parts of a car. Most of the breakdowns occur in the piston group of the internal combustion engine, especially in the compression rings. This article will present a new design of an innovative repair kit for vehicle units. The paper examines new principles and effects for reducing friction. The main difference between the proposed solution is the use of spring rings instead of a simple installation of compression piston rings. The main goal of functional improvement is to increase the strength and technical indicators of friction between the piston rings and the cylinder sleeve. The new technology reduces the natural wear of the piston rings, as well as the integrity of the grooves in which the rings are installed. In addition, the new kit improves sealing and increases the shock absorption capacity when the combustible mixture is ignited. The presented spring assembly was tested in a virtual environment, taking into account all external factors and processes that can affect its operation. According to the results of experiments and mathematical calculations, this kit can work in real working conditions without deformation and loss of functions. Based on the results of the test carried out in the SolidWorks simulator and the mathematical model of the model compliance, it can be said that the proposed solution is a working solution designed to improve the performance of the CPG

10.48081/PUZF2504

2025

Issue 4

When developing technology for producing high-quality safflower oil, it is crucial to enhance the efficiency of refining processes. Among other things, primary refining processes are essential for separating safflower oil from mechanical impurities. In safflower production, one of the first refining processes is the separation of safflower from the husk. Separation of safflower from the husk not only increases the oil yield, but also improves the quality of the oil, contributing to the technology of obtaining all safflower oil. This is because separating the husk from the grain prevents the formation of fine suspended or "reticulated" wax crystals that separate the wax from foreign matter, such as beeswax, which degrades the quality of the oil. Therefore, processing safflower without peeling reduces the efficiency of safflower oil technology development work. This article presents a method for separating the husk from the kernel in a screw pneumatic classifier, utilizing airflow to optimize the safflower seed hulling process. For oilseeds, this approach will be a fundamentally new solution. In this case, there is an opportunity to double the airflow with centrifugal force in the screw channel of the pneumatic classifier compared to the straight-line inertia force during the husking process. Thus, based on the proposed husking equipment, from the social, economic, and industrial efficiency perspectives, husking efficiency is increased, equipment design is simplified, and equipment dimensions are reduced. However, judging by comparison with the force of inertia in a rectilinear flow, the path of aerodynamic air flow is not reduced, but, on the contrary, gives the possibility of its increase. Reduce the length of pneumatic conveying and air consumption by half, resulting in energy savings for husking of up to 50%.

https://doi.org/10.48081/AIDZ8183

2025

Issue 4

The study investigates the process of pelletizing secondary products of ferrochrome production with the aim of recycling and reintroducing them into the metallurgical cycle. The physico-chemical characteristics of sludges and dust emissions, their particle size distribution, moisture content, and concentrations of chromium, iron, and silicon oxides were analyzed. Laboratory experiments were conducted to form pellets using various binders, including bentonite, lime, sodium silicate, and organic additives, as well as their combinations. X-ray diffraction, microscopy, and chemical analysis methods were applied to characterize the materials. Pelletizing parameters—component ratios, mixture moisture, drying, and heat treatment conditions—were optimized considering their influence on crystalline phase formation and strength properties. Mechanical strength, thermal stability, and resistance of the granules to mechanical stress and agglomeration during transportation and furnace loading were evaluated. Pilot tests of the technology were carried out on industrial samples, and an economic and environmental assessment of its implementation was performed. The results demonstrated that the use of combined binders and rational technological regimes ensures the production of strong, heat-resistant, recyclable pellets, reducing waste volume and improving the resource efficiency of ferrochrome production.

10.48081/YSPV5983

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

The article analyzes the development of research in the field of global supply chain management for semiconductors and strategically important minerals using bibliometric and content analysis. Special attention is given to the resilience and sustainability of production and logistics systems under conditions of digital transformation and geopolitical instability. The methodological basis consists of a bibliometric analysis of publications from leading databases for the period 1994–2025, which made it possible to identify key trends, research clusters, and the dynamics of the scientific agenda. The content analysis revealed the directions of implementing digital tools—such as the Internet of Things, machine learning, big data, and predictive analytics—into supply chain management. The results indicate the emergence of a new research paradigm in which the integration of digital technologies serves as a strategic tool for enhancing transparency, flexibility, and resilience in global supply chains of semiconductors and critical resources.. Keywords: global supply chains, semiconductors, strategic minerals, data-centric approach, bibliometric analysis, big data, Internet of Things, machine learning Funding information. This research was funded by the Science Committee of the Ministry of Science and Higher Education of the Republic of Kazakhstan (Grant No. AP27508139).

10.48081/CRTP7219

2025

Issue 4

The article systematizes methodological approaches to modeling logistics systems, considering them as complex hierarchical, multilevel and stochastic objects operating in conditions of limited resources, uncertainty of demand and variability of transport infrastructure. It is shown that the integration of system, mathematical, hierarchical, and digital approaches ensures reproducibility, verifiability, and scalability of solutions. As a case study, the tourism logistics of the southern region of Kazakhstan is considered, where the hierarchical method serves as a universal mechanism for decomposing the global problem of flow distribution with subsequent coordination of local solutions. Formal formulations for optimizing the distribution of flows have been developed, algorithmic procedures (Lagrangian relaxation, coordination iterations) have been formulated, and comparisons with alternative methods (linear/integer programming, simulation modeling, dynamic programming, Monte Carlo methods, and multi-criteria optimization) have been performed. Special attention is paid to the role of digital platforms in data integration, the use of IoT/Big Data for monitoring tourist flows, as well as taking into account the environmental capacity of territories. Additionally, the issues of transport accessibility of key tourist routes, the interaction of road and rail transportation, as well as the influence of seasonality on fluctuations in tourist demand are analyzed. The prospects of introducing intelligent transport systems that allow real-time adaptation of logistics solutions to changing conditions are being considered. The proposed solutions can serve as a basis for strategic planning, increasing the sustainability of the transport and logistics system and developing tourism in the face of global challenges. It is emphasized that an integrated approach to modeling not only improves the efficiency of flow management, but also ensures a balance between economic interests, tourist comfort and the preservation of the natural potential of the region.

10.48081/IGCI5887

2025

Issue 4