Cutting & Tools in Technological System

MODERN MATERIALS AND PROCESSING TECHNOLOGIES AS A FACTOR IN THE DEVELOPMENT OF THE AEROSPACE AND ROCKET INDUSTRIES

Lyudmila Kalafatova — 2025-12-15

The article examines the impact of modern structural materials' characteristics on the advancement of the aerospace and rocket industries. The growing role of ceramic materials with unique properties is emphasized: heat resistance, high hardness and strength; resistance to oxidation and corrosion; radio transparency; lower density compared to metals. It is often the case that they are indispensable in the manufacture of elements of rocket systems and defense industry products. However, technical ceramics belong to the category of difficult-to-machine materials, which complicates the processes of manufacturing critical products from them. Possible ways to improve the efficiency of manufacturing rocket antenna fairing - thin-walled shells of complex geometric shapes made of sitalls (a type of glass ceramics) are considered. Options for improving traditional technological processes for the manufacture of fairings using CNC machines for their mechanical processing are proposed. The use of additive SLS technology in the production of antenna fairings is substantiated. A variant of an improved technological process for manufacturing antenna fairings was presented.

EFFECT OF CHANGING THE MILLING HEAD DIAMETER ON THE INHOMOGENEITY OF THE MACHINED SURFACE TOPOGRAPHY

Antal Nagy — 2025-12-15

The geometry of the tool and the workpiece plays a decisive role in the formation of the topography of a machined surface. Depending on the kinematic conditions of the machining process, they influence both the magnitude of surface roughness and the irregularity of the topography. This paper presents an investigation of the variation in topographical inhomogeneity resulting from changes in the tool diameter used in face milling. The results showed that increasing the diameter – while keeping all other parameters constant – significantly increased the values of amplitude and functional roughness parameters measured on the surface at the same measurement position. The decreasing trend of the values with increasing distance from the path of the tool axis was consistent, and its magnitude gradually diminished at measurement locations taken at greater distances. However, when the distance was expressed as a proportion of the tool diameter, the values exhibited similar degrees of variation.

MODELING THE IMPACT OF NONLINEAR OSCILLATIONS ON THE QUALITY OF THE WORKING SURFACE OF PARTS IN FINISHING OPERATIONS

Anatoliy Usov — 2025-12-15

To establish analytical conditions for detecting hereditary defects in ferroceramic and ferromagnetic parts and to define machining parameters that prevent crack formation. Magnetic induction scattering is modelled to estimate defect geometry and depth; thermomechanical processes during grinding are analysed using the “weakest link” hypothesis and criteria based on temperature, heat flux, forces, and stress intensity. Obtained expressions describe magnetic field perturbation and allow evaluating defect size, while derived conditions prevent their growth into main cracks. A unified analytical framework combines magnetic defect detection with crack-resistance modelling. The results support selecting grinding modes and tool characteristics for defect-free finishing of materials prone to cracking.

IMPROVING THE EFFICIENCY OF TOOLS FOR TURNING HIGH-STRENGTH MATERIALS

Viktor Kovalov — 2025-12-15

The article presents the results of a comprehensive study of heavy turning of high-strength steels used in structural components of defense and energy engineering, particularly in the tyres and rims of railway wheelsets. The aim of the work is to improve the efficiency of cutting tools by optimizing their geometry and cutting parameters based on the analysis of thermomechanical loading, the stress–strain state of the cutting wedge, and the regularities of tool wear development. The study includes modeling of temperature fields and contact stresses, analysis of the action of elementary force components on the rake and flank surfaces of the tool, as well as experimental determination of cutting forces, wear, and surface roughness during turning of steels with hardness of 2850–3600 MPa. The obtained results show that the geometry of the cutting part is a critical factor in ensuring tool stability: the use of a shortened rake face, strengthening chamfers, and a rational nose radius reduces contact stresses and local overheating in the tool-nose zone. Optimal cutting conditions (V = 45–55 m/min, s = 1.4–2.0 mm/rev, t = 6–8 mm) were established, ensuring minimal wear intensity and a stable chip-formation process. The practical significance of the work lies in the possibility of increasing tool life, machining accuracy, and technological reliability in the production of high-responsibility components from high-strength steels.

INVESTIGATION OF FUNCTIONAL SURFACE ROUGHNESS PARAMETERS ON STEEL SURFACES MACHINED BY ELECTRO-DISCHARGE MACHINING

Zsolt Maros — 2025-12-15

The surface quality produced by electrical discharge machining (EDM) nowadays allows these surfaces to be used directly as functional surfaces—often without the need for post machining—such as in the production of plastic moulding tools. This highlights the importance of surface quality assessment not only through traditional amplitude parameters but also through so-called functional roughness parameters. This paper presents the results of studies in which EDM machined tool steels were investigated using functional surface roughness parameters. Such parameters effectively characterize the operational behaviour and applicability of machined surfaces.

FORM ACCURACY AND CUTTING FORCES IN TURNING OF X5CRNI18-10 SHAFTS: ASSESSMENT OF FEED FORCE VARIATION AND ITS RELATION TO FORM DEVIATIONS

Wafae El Majdoub — 2025-12-15

The study presented in this paper aims to provide insight into how cutting parameters, including cutting speed, feed, and depth of cut, influence feed force and form deviations during the X5CRNI18-10 shafts machining. Many experiments were carried out at two depths of cut levels (0.5mm and 1mm) to investigate the effects of cutting speed and feed on feed force, roundness, and waviness. The findings showed that increasing the depth of cut has the strongest influence on cutting force and form deviation. In parallel, higher feed affected the roundness and waviness, leading to a reduction in the surface quality due to the tool deflection and vibrations. Cutting speed had a small impact; however, it is still crucial to select cutting parameters carefully to secure a proper balance between dimensional accuracy, surface quality, and machining efficiency.

RESEARCH OF THE PROCESS OF DRILLING HOLES IN PARTS MADE OF POLYMER CARBON PLASTIC

Victor Antonyuk — 2025-12-15

The article presents analytical models for evaluating the process of drilling holes in parts made of fibrous composite materials by drilling, which is accompanied by unusual defects that are not typical for metal cutting, such as delamination, chips, hairiness, composite chipping, thermal destruction and uncut fibers around the drilled hole, as they affect the service life of composite details. The influence of processing conditions and modes (feed, spindle speed and drill tip angle) of carbon fiber on the drilling quality parameters (delamination coefficient and roughness of the machined surface) and axial cutting force is established. The delamination coefficient (Ksr) in composite materials was taken into account, for which the critical axial force was determined, the excess of which leads to delamination of the hole surface, by an indirect method - by measuring the axial force. Measurement of the axial force and determination of its parameters were performed using an experimental setup. The machining modes during experimental studies varied within the following limits: the number of revolutions n - from 1250 to 4000 rpm and the feed S - from 50 to 800 mm/min. Drilling was performed on a vertical milling machine with a CNC SMG-300 with a maximum spindle speed of 5000 rpm. carbide drills with a diameter of 5 mm SANDVIK class ISO K20. Analytical dependencies were constructed using modern methods of multivariate statistical analysis - by the method of group consideration of arguments for calculating the quality parameters of holes in composite materials from cutting modes: the number of revolutions of the drill n, the feed S and the angle φ at the tip of the drill. An optimization problem of nonlinear programming was solved where the material removal rate was chosen as the optimality criterion. The value of the optimal mode for drilling holes in carbon fiber with a carbide drill VK8 with a diameter of 5 mm with an angle at the edge 2φ = 100° (V = 2.83 m/min, S = 406.26 mm/min) was established, which ensures maximum hole processing performance. The results of the study are the practical importance for mechanical engineering and the aviation industry, as they allow to increase the stability and productivity of technological processes for manufacturing products from composite materials.

DIAMOND ABRASIVE TREATMENT: TRIBOLOGICAL ASPECT (REVIEW OF MODERN RESEARCH)

Valerii Lavrinenko — 2025-12-15

The importance of developments to overcome friction and wear is largely due to the fact that the energy consumed by the manufacturing industry is almost a third of the total energy consumed. That is, the tribological aspect in the processes of diamond-abrasive processing is quite significant and must be taken into account. Recently, new modern developments have appeared in the literature that somewhat clarify this direction, both from the point of view of the diamond abrasive tool and the tribological behavior of various diamonds, including those with coatings. It is these developments that are covered further in our review of modern publications. Additive manufacturing (AM) methods have significant advantages for obtaining individual products and prototypes, allow to reduce costs, and also speed up the release of products to the market. Nowadays, this direction has begun to be used for diamond-abrasive tools. Of course, new binders for the working layer of the diamond tool have been developed for such energy-efficient AM technology. It is shown that the cutting forces and friction coefficients of microtextured diamond tools are significantly reduced. The tribological behavior of diamonds against various materials is fundamental for their use in the abrasive and bearing industries. It has been proven that, in comparison with ordinary diamond grains, porous diamond grains with an increased number of microedges effectively reduce the cutting force and heat generation. It is shown that the application of the effect of further mechanochemical influence during the coating of diamond abrasives, both on the diamond-bond boundary and on the contact of the surface of the diamond grain with the processed material, allows to increase the efficiency of the use of the diamond-abrasive tool. Attention is drawn to what kind of impurities are introduced into the contact zone during diamond-abrasive processing to change the tribological parameters. At the same time, the most widely used is h–BN, which with a layered crystal structure is one of the types of effective solid lubricants, especially at elevated temperatures. Attention has been paid to emerging materials such as graphene oxide and carbon dots (CD), a kind of carbon-based nanomaterials, which have been widely used as highly effective lubricant additives.

INFLUENCE OF MACHINING-BASED POST-PROCESSING ON THE SURFACE TOPOGRAPHY OF DMLS 316L STAINLESS STEEL FOR FUSION-RELEVANT APPLICATIONS

István Sztankovics — 2025-12-15

This study investigates the effect of machining-based post-processing on the surface topography of Direct Metal Laser Sintered (DMLS) 316L stainless steel intended for fusion-relevant applications. Cubic samples (30 × 30 × 30 mm) were produced by additive manufacturing and subsequently finished by face milling and surface grinding under two parameter settings each. The surface topography was characterized using an AltiSurf 520 optical system in accordance with ISO 25178. The as-printed surface exhibited high roughness (Sa = 8.899 µm, Sz = 79.427 µm), while all post-processed surfaces showed significant improvements. The lowest roughness (Sa = 1.346 µm) was obtained after grinding at 7 m/min feed rate. Skewness and kurtosis analysis indicated that machining transformed the peak-dominated surface into a more uniform, near-Gaussian texture. The results confirm that controlled milling and grinding operations can effectively enhance the surface integrity of DMLS 316L components. These findings demonstrate the potential of hybrid additive–subtractive manufacturing to produce surfaces suitable for the vacuum and functional requirements of fusion technology applications.

PROJECT MANAGEMENT BASICS FOR 3D CONCRETE PRINTING: TIME CALCULATION STANDARDS FOR DESIGN AND TECHNOLOGICAL PREPARATION AND QUALITY ASSURANCE

Yaroslav Garashchenko — 2025-12-15

This research establishes the first comprehensive project management framework for 3DCP through quantitative standards for design preparation, technological setup, and quality management. Based on systematic analysis of construction projects completed during 2023-2025 by "Geopolimer" LTD (Kharkiv, Ukraine), we developed mathematical models for time estimation incorporating perimeter length, geometric complexity, and feature count parameters. Regression analysis of project data enabled formulation of predictive equations: design preparation time accounts for base setup, perimeter-dependent modeling, and complexity coefficients (complex curved surfaces with architectural details). Technological preparation time integrates G-code generation, trajectory verification per meter, and build step validation. A systematic complexity classification system evaluates four geometric factors: curved surfaces percentage, architectural detail count, protruding elements, and internal cavity complexity, enabling quantitative risk assessment and resource allocation decisions. The framework incorporates a three-level quality management system with standardized defect classification (aesthetic, attention-required, critical) defining acceptance criteria for crack dimensions, surface porosity, and structural integrity. Trajectory verification methodology enables proactive defect identification, detecting 85-90% of potential issues before production begins. Economic analysis demonstrates 8-12% rework cost avoidance, 15‒20% preparation time savings, and 5‒10% schedule compression, with return on investment achieved within 0.5‒1.5 months. Case study validation on a 174 m² residential structure demonstrates framework effectiveness: calculated preparation time of 45.1 hours versus actual 47.2 hours. The framework facilitates 3DCP transition from experimental technology to predictable industrial process, enabling evidence-based project planning, systematic risk management, and competitive market positioning. Future research directions include expansion to additional printer types, integration with Building Information Modeling workflows, real-time computer vision quality monitoring, and long-term performance tracking for continuous standard refinement.

PERFORMANCE ANALYSIS OF ROTATING LATENT HEAT STORAGE SYSTEM

A G GUNA — 2025-12-15

In recent years, shell and tube latent heat thermal energy storage system (LHTESS) with phase changing materials (PCM) are used to store energy. The major drawback of latent heat storage system is due to low thermal conductivity of PCM the heat transfer is low. In this study, a 2-dimensional horizontal shell and tube latent heat storage system is considered, the rotation is implemented to accelerate charging process of the system. ANSYS FLUENT 2022 R2 software is used for the simulation and calculation. Paraffin wax (n-octadecane) and water are used as PCM and hot fluid (HTF) respectively. The simulation and calculation are carried out for 0.5 rpm, 1 rpm and 1.5 rpm and these results are compared with stationary counterpart. The result show that rotation accelerate melting process. The percentage thermal enhancement between rotation and stand stand still for 0.5 rpm, 1 rpm and 1.5 rpm are 8%, 18.61% and 25.38% respectively.