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The CuZn10 alloy, a prominent brass variant known for its excellent cold formability, corrosion resistance, and suitability for various cold forming processes such as bending and stamping, finds widespread application across numerous industries. Optimizing its performance for specific industrial demands necessitates a thorough understanding of how different preparation technologies influence its intrinsic properties. This study provides a comprehensive examination into the impact of various processing routes on both the structural evolution and mechanical characteristics of deep-drawing CuZn10 brass. Utilizing advanced analytical techniques, including Electron Backscatter Diffraction (EBSD) analysis, the research systematically investigates microstructural changes, grain orientation, and texture development resulting from distinct manufacturing processes. The findings delineate clear correlations between specific preparation methodologies and the resulting mechanical properties, such as hardness, strength, and ductility. This work aims to establish a foundational understanding that can guide industrial practitioners in selecting optimal processing technologies to tailor CuZn10 alloy for enhanced performance and efficiency in its diverse applications. The insights gained are critical for refining manufacturing protocols and improving material quality in an industrial context.

The influence of the casting method on the microstructures of Al-Cu-Li-Mg-Zr-Sc was examined. The techniques include mold casting, twin-roll casting, and melt spinning. Estimated solidification rates up to 107 K·s−1 produce dendritic solidification with eutectic cells ranging from 500 nm to 50 μm, decorated by primary phase particles with thicknesses from 200 nm to 3 μm. Exceeding this solidification rate results in near-diffusionless solidification, which traps more solutes in the matrix. This type of solidification yields a more supersaturated material with nearly 90% of the total Cu content in the matrix and a fine dispersion of nanoscale spherical precipitates below 100 nm in diameter. The small addition of Sc during casting primarily affects the material at low cooling rates, where primary Sc-containing particles modify the grain boundary shape.

Precision mirror mould CNC machining is a technology of great importance in industrial manufacturing. Precision mirror moulds are usually used to produce high-precision, high-quality parts and products, which are widely used in automotive manufacturing, aerospace, electronic equipment and other industries. However, the traditional mould polishing process often fails to meet the manufacturing needs of precision moulds, so the application of CNC machining technology has become an effective way to solve this problem. Through the use of CNC machine tools and computer control systems, etc., the detailed formulation of the process plan, so that precision mirror mould CNC machining can achieve high efficiency, accuracy and stability of the machining process, to improve the quality and productivity of the mirror mould. Therefore, the applied research on CNC machining of precision mirror mould is of great significance and economic value.

Past efforts which focused on the essential monitoring of the chain tension of scraper conveyers employed in fully mechanized coal mining operations have developed innovative power solutions based on the incorporation of piezoelectric devices that generate the electrical power required for the wireless transmission of chain tension data based solely on the vibrations of the scraper conveyor itself. However, these past studies have failed to evaluate the effects of different environmental factors on the electricity generating capacity of the piezoelectric devices. The present work addresses this issue by evaluating the maximum peak-to-peak voltage generated by a variable excitation piezoelectric device experimentally under a wide range of mechanical excitations, including static applied loads of 1600 g, 3200 g, and 4800 g with added oscillatory loads of different frequencies of 1.0 Hz, 2.0 Hz, and 3.0 Hz, and displacement amplitudes of 1.0 mm, 2.0 mm, and 3.0 mm. Compared with excitation frequency and excitation load the impact of an oscillatory load amplitude increasing from 1.0 mm to 3.0 mm on the obtained peak-to-peak voltages is quite profound, where the peak-to-peak voltage of the device increases by nearly 270%. The kind of piezoelectric power generation device which can adjust many kinds of external excitation is innovatively designed. The efficient and stable power supply of the piezoelectric device to the tension detection system of the scraper conveyor is realized.

The paper presents the analysis of the gantry crane loading when driving along the crane track, using a Working model 3D, for which the analysis of the gantry crane frame loading was performed. The gantry crane is designed to remove dirt in front of the turbine under the water surface. For the gantry crane which moves along a track, the directional and vertical unevennesses were determined by experiment and are given in graphic and numerical form in (mm), relating to A track and B track with a total track length of 450 (m). Based on the knowledge of the unevenness of the rail track, the four random functional dependencies defining the irregularities of the individual rails as input variables were used for the kinematic excitation of the individual wheels of the gantry crane. The stress analysis was performed for a travel speed of 30 (m.min^-1) and a lift of 10 (t) under the given loading. The results of the stress analysis are presented in graphic form.

In previous studies, an asymmetric product is formed by shear spinning. The wall of the product couldn't be perpendicular to the bottom since the thickness of the wall would reduce to zero in shear spinning. In order to break through the limitation and form an oblique cylindrical shape, an asymmetric multipass spinning method combing conventional spinning with asymmetric spinning was developed in this research. The roller trajectory of asymmetric multipass spinning is deduced. The thickness variation is discussed by analyzing the movement of the roller. The thickness distribution and the surface quality with different experiment parameters are discussed. It indicates that a smaller roller feed rate f and a smaller incremental angle ∆α can improve the surface quality.

The objective of this work is to assess cutting speed during the wire electrical discharge machining (WEDM) depending on the machine parameters setting (gap voltage, pulse on time, pulse off time, wire speed and discharge current) and follow-up assessment of the surface quality achieved. In order to achieve efficient machining the maximum cutting speed is required, however maintaining of the required quality and functional characteristics of the machined surface must be considered. Surface morphology during the wire electrical discharge machining is formed by a high number of craters, of which depth has direct effect on area parameters and profile parameters of the surface quality. These parameters were evaluated using Contactless 3D profile-meter based on the principle of coherence correlation inter-ferometry IFM G4 from the Alicona producer.

This article presents the development and validation of SBRI (Small Business Digital Maturity Assessment and Road to Industry 4.0), an innovative methodology for assessing digital maturity and supporting digital transformation specifically designed for small manufacturing enterprises in the context of Industry 4.0. Unlike existing models, which are often too complex or unsuitable for smaller organizations, SBRI considers the unique characteristics and constraints of small businesses. The methodology includes five key dimensions: Strategy, Technology, Process, People, and Organization, elaborated into 25 subdimensions with specific maturity criteria and indicators. The SBRI includes a structured roadmap for digital transformation through a proposed digital maturity continuous improvement cycle. An empirical study involving 23 small manufacturing enterprises in the Czech Republic has demonstrated the validity and practical applicability of the methodology. The results showed an average level of enterprise digital maturity of 0.9 on a scale of 0 – 4. These findings suggest that small businesses are just at the beginning of their digital transformation journey. Therefore, the SBRI methodology represents a valuable tool for navigating small businesses through their digital transformation journey, contributing to academic discourse and practical application of Industry 4.0 principles in the small business segment.

The article provides an analytical solution for the dynamics of a vehicle chassis designed for both road and rail operation, featuring either single or multiple primary linear suspensions using coil springs. It derives the equations of motion for a simplified two-axle chassis model that includes both a basic primary suspension and a simplified chassis suspension. The study focuses on the simplest calculation model to analyze suspension behavior, taking into account the asymmetry in spring stiffness and geometric positioning. There is an unequal distribution of weight across the vehicle body. An analysis is conducted on a comprehensive vehicle model with nine degrees of freedom. The analytical solution is obtained using Lagrange equations of the second kind, alongside various calculation techniques such as Laplace transformation. Due to the scope of the article, calculations of all coefficients of the matrices are not presented, but a link to other works of the authors is given, where these procedures are presented. The proposed analytical solution makes it possible to derive an effective algorithm for the application of computer technology. The use of the proposed procedures allows determining the permissible asymmetry of vehicles for safe driving, taking into account structural asymmetry, kinematic excitation asymmetry (always occurs) and suspension asymmetry (almost always occurs).

Gears and toothed parts are significant components in power transmission systems. These parts usu-ally manufactured by traditional methods such as machining by milling or forming by rotary forging. In this study, the forming of solid gears or toothed parts using a forging process that combines rotary forging and ballizing technique. The specimens were placed inside the die with excessive volume to fill the toothed part in the die. The forming tool applies pressure to the specimen while rotating it together with the die by the lathe machine chuck, while the tool advances continuously in the direc-tion of the die. This reduces height of the specimen and increases its diameter, causing metal flow to fill die cavity teeth and form the gear or toothed part required for production. Two sets of experi-ments were performed. In the first set, optimization for the appropriate volume of four different sizes of dies and four forming tools was conducted. While in the second set, the effects of forming process variables on the forming load and tooth filling percentage was studied. The results showed that the best tooth filling ratio happened with specimens size of 1.2 to 1.4 times the volume size of the desired tooth for filling. The results also revealed that the forming speed, die size, and forming tool diameter affect the filling ratio and forming load.

An innovative way of using DCPD (Direct Current Potential Drop) method for off-line and online monitoring of critical parts of energy equipment in operation is presented. There are only a few NDT methods that allow detection and monitoring of defect growth in components at high temperatures and pressures. Monitoring of steam pipes and critical pipeline components in operation has been carried out for several years with different results. a relatively new way of using the DCPD method outside the laboratory is described. The carried-out tests were intended to resemble operational loads as much as possible. Therefore, the tests were performed at a temperature of 20 °C and at an increased temperature of 550 °C. By gradually deepening the groove (slot) simulating the crack type defect in predefined steps, the growth of the defect was simulated up to the full wall thickness of the test sample. The primary evaluation was carried out from the absolute and relative values of measured resistance. The disadvantage of these values is their dependence on the temperature of the monitored area of the test sample and on possibly interfering DC voltages.

Due to their availability and ease of use, additive techniques are experiencing dynamic development. This applies to both the industrial sector and individual recipients. The authors of numerous publications address in their research the subject of the influence of selected printing process parameters on the strength of models, usually made using selected MEX (Material Extrusion) methods. Among the MEX methods, the most frequently chosen are the FFF (Fused Filament Fabrication) and FDM (Fused Deposition Modeling) methods. This is due to the high availability and low cost of devices using the methods mentioned above and the high availability of polymer materials. In their research, the authors increasingly consider the influence of the internal structure of the samples and their density on selected strength parameters, often without considering whether they affect the geometric accuracy of sample mapping. For the above reasons, it was decided in the article to conduct research covering the indicated subject using the example of standardized samples made of six selected polymers used in the FFF method.

Atomic Diffusion Additive Manufacturing (ADAM) is a progressive layering process based on metallic materials with a plastic binder designed to extruse the material. The ADAM process can be classified as an indirect additive manufacturing process in which a solid fiber of metal powder enclosed in a plastic binder is applied. After creating a 3D object by the ADAM process, the excess plastic binder is removed in the cleaning chamber and vacuum sintering of the 3D object is performed. This work aims to provide a preliminary characterization of the ADAM process and compare the achieved results with the application most implemented so far in additive manufacturing for metal 3D objects using Selec-tive Laser Melting SLM. In particular, the density and microstructure of the applied process and mate-rial 17-4PH are studied, while optimal or recommended technological parameters of production facili-ties are applied. Furthermore, the dimensional accuracy of the ADAM process is observed, which is evaluated by means of IT accuracy levels according to the ISO reference artifact. Due to the applied AM process, the final character of a 3D object depends on technological parameters. The weight of a 3D object is low compared to the material processed by additive manufacturing processes in a powder bed. The dimensional accuracy and roughness of the surface depends on the geometry, orientation, and position of the individual shape specifications of the 3D object. Additive technologies generally achieve a degree of accuracy of approximately IT12 to IT13, which is comparable to traditional semi-finished metal manufacturing processes.

In this study, the ballistic resistance of multi-layered composite armour is experimentally investigated. The composition of this armour consisted of armour steel Armox 500T, para-aramid fabric Twaron CT 747 and ultra-high molecular weight polyethylene Endumax Shield XF33. To compare the ballistic resistance, the ballistic resistance of the armour with the perforated steel Armox 500T was tested. The rifle cartridges 7.62 x 51 mm FMJ NATO M80 were used to test this resistance. The aim of this experiment was to compare the ballistic resistance of unperforated and perforated steel Armox 500T. As part of the experimental part, the chemical composition and microhardness of the steel Armox 500T was verified. The hardness of the composite materials was also measured for optimal armor configuration. After the projectile impact, the damage mechanism of the steel Armox 500T and the composite materials were investigated by using optical and electron microscopy. It was proved that the ballistic resistance of the perforated steel depends on the used pattern. Based on the performed experiments, the steel Armox with pattern A effectively reduced the weight of the testing configuration and absorbed all the kinetic energy of the projectile 7.62 mm FMJ M80.

The article is focused on the analysis of the additive technology (3D printing) applicability by using DMLS in the production of the reducing valve part, i.e. atmospheric resistor. Currently, the men-tioned part is produced by EDM in combination with soldering from the Inconel 718 steel. The use of additive technologies brings the assumption of greater flexibility and economy of production, which is verified by a set of analyzes focused on the accuracy of production and the utility properties of the mentioned part. In addition to technological aspects, such as individual production processes, economic aspects are also compared. Individual comparisons are the basis for assessing whether replacing the conventional production approach with 3D printing is advantageous in this case. The results of this assessment can subsequently be used for future applications of the considered additive manufacturing approaches in the case of similar components.

The thesis deals with the surface treatments of bearing steel processed for wind turbines, on which the quality parameters of the surface treatments performed were compared. This is blackening, which is a method of surface treatment that allows the protection of the base material from the negative effects of external influences, in particular from moisture and associated corrosion. The application of surface treatment by blackening contributes to a better and more efficient start-up of the bearing in service. In the experimental part, the individual results of the structural analysis carried out for all types of materials investigated are evaluated, with the analysis focusing on the structural properties, the quality of the adhesion properties and the influence on the service life of the machine components. Electron microscopy was used to investigate the structural properties of the layer as well as the base material, which allowed to obtain the necessary data to meet the objectives of this work.

The thermal stability of nanocrystalline Cu nanoparticles was investigated using a combination of in situ TEM annealing experiments and molecular dynamics (MD) simulations. Nanoparticles prepared by a gas aggregation source exhibit an average size of ~100 nm and are predominantly polycrystalline, with grains of ~25 nm. Upon annealing up to 600 °C, the particles preserve their external morphology without signs of sintering, while their internal structure evolves through progressive grain growth. Orientation mapping revealed an increase in Σ3 and other special boundaries, consistent with the tendency of grain boundary networks to evolve toward low-energy configurations. MD simulations partially reproduce the general coarsening process and the formation of nearly monocrystalline particles, but predominantly produce {111} stacking faults rather than Σ3 twins. This discrepancy is attributed to the limited timescale and idealized initial conditions of the simulations compared with the defect-rich experimental particles.

The paper deals with methodology of prediction of adhesive bonded joints strength. Problematics of adhesive bonded joints is a very complex task. There are several different (different precision and different complexity) mathematical models of adhesive bonded joints, which attempts to describe the real behavior of adhesive and adhesive bonded joints during load as accurately as possible. This article presents a comprehensive overview of what to take into account and how to proceed with designing/controlling the strength of adhesive bonded joints. Mathematical models are supplemented by material data from experimental tests. The proposed methodology takes into account both adhesive and cohesive properties (material of bonded parts, surface treatment of bonded material, type of adhesive, thickness of adhesive, bonding technology, loading modes etc.). Methodology "how to proceed" is described in detail and is complemented with a flowchart.

When analyzing the natural frequencies of a gear mechanism, it's crucial to consider the mesh stiffness, which is influenced by the number of teeth in the mesh. Mesh stiffness behaves as an internal excitation source for the dynamic system, affecting the resulting frequency spectrum. This paper presents an experimental determination of gear mesh stiffness supported by analytical-simulation models of mesh stiffness, outlining common modeling methods and detailing the experimental setup and test specimens. The obtained data are then compared with simulation models of mesh stiffness, discussing the significance of this comparison and emphasizing the role of experimental data in validating and refining existing models of mesh stiffness. The experimental measurement of mesh stiffness described here emerges as a valuable tool for accurately representing mesh stiffness during engagement.

The article presents the possibilities of using wavelet transform and fast Fourier analysis (FFT) to evaluate the signal collected during roughness measurement. During the tests, high-density polyeth-ylene was turned using variable cutting parameters. During cutting, the tool feed was changed to ob-tain roughness structures of different types and with varying degrees of anisotropy. The measured roughness profiles were filtered with Daubechies 6 (db6), Morlet and "Mexican Hat" wavelets and examined using Fourier analysis. The research carried out shows how the machining conditions affect the surface condition and the stability of the cutting process under variable machining conditions for high molecular weight polymers. The effectiveness of the continuous wavelet transform (CWT), sup-plemented with data obtained from Fourier analysis, in identifying places and detecting the nature of disturbances in the generated roughness signal is also shown.

Nowadays, increasing emphasis is placed on the production of parts using additive technologies, particularly for alloys that are difficult to process. In addition to standard additive technologies, such as Selective Laser Melting (SLM), other additive technologies are increasingly being used, including Directed Energy Deposition (DED). DED offers several advantages and is utilized both for producing entire components and for repairing damaged parts through weld cladding. In this study, the possibility of weld cladding of nickel-based hard alloys using DED was tested using a laser as the energy source to melt the additive material. The tests performed showed that selected nickel alloys, suitable for mould repair, are difficult to weld. Therefore, the experiments sought optimal process parameters and defined the accompanying technological operations in order to produce a crack-free weld cladding.

Tree-like branched Al-Al₂Cu heterogeneous nanostructures with a high surface area ratio were successfully fabricated using magnetron sputtering of Al matrix and Cu nanoparticles, followed by in situ annealing. The method enables precise control over the composition and morphology of the nanosized columnar Al₂Cu phase grown on the substrate and embedded in the Al matrix. The formation of Al₂Cu begins at the initial locations of sputtered Cu nanoparticles. Further annealing promotes their coalescence and coarsening. Orientation relationships examined in several Al₂Cu particles revealed a semi-coherency with the Al matrix. The high surface area and tunable composition highlight the potential of these nanostructures for advanced battery anodes, with tailored geometry achieved through controlled processing conditions.

The paper presents work aimed at building practical applications of virtual reality (VR) in manufacturing environments. It contains studies of the optical properties of cameras and lenses aimed at the selection of an optimal set (camera, adapter, lens) for the realization of recordings and video transmissions in stereoscopic format for VR. In response to the increasing trend in the number of applications of VR systems in the industry, works have been initiated with the purpose of building a system levelling image noise identified thus far as an obstacle to the effective utilization of VR in production systems. It was considered that picture error correction can significantly increase an already big data stream from the recordings. Based on it, a set of parameter values was defined which determined the selection of study equipment. Three research areas were set: the verification of the optical correctness, the study of image defects and their correction and the determination of the maximum optical resolution and the achievable image parameters in various lighting and environmental conditions. An example was presented for the application of a projected system for the monitoring of undesirable events/movement at work stands and key areas of production halls as well as training in the high-risk production zones.

The article highlights the promising potential of automating the forging process to enhance the durability of multi-cavity forging tools. Entrepreneurs aim to boost production efficiency by increasing output per unit of time and reducing the degradation of forging dies and punches. The high costs associated with specialized materials and complex manufacturing processes for these tools elevate the final product price. Automation offers a viable alternative, ensuring consistent process parameters and reducing the physical strain on workers. This consistency leads to extended tool durability, even without the use of special manufacturing techniques for their production. The study simulates the durability of multi-cavity dies in automated operations, demonstrating substantial advantages compared to manual forging. Simulation programs for forging processes and tool durability offer significant cost savings by providing insights into potential fatigue cracks, aiding in decision-making, and verifying operational parameters and tool designs. These simulations reduce the need for extensive: real-world tests and modifications of the forging tools.

Five-axis machine tools are key equipment to process impellers, blades, and other precision mechanical parts. However, the accuracy of the machine tools is significantly influenced by assembly errors, and over time, these errors may change, further impacting the machining accuracy. Traditional laser interferometry technology can identify such assembly errors. The development of on-machine measurement technology has enabled methods that utilize on-machine measurement for assembly error calibration, improving calibration efficiency. The study introduces an efficient method to calibrate the assembly errors of machine tool rotary axes. First, the kinematic model for a machine tool is develop. Subsequently, utilizing on-machine measurement technology, the assembly errors of the rotary axes are calibrated, and the calibration uncertainty is analyzed. The results of the experiment confirm the validity of the calibration method. This method can be applied for periodic calibration of machine tool assembly errors, continuous monitoring variations in machine tool accuracy and ensuring the stability of machining quality.

Conventional spinning is one of the oldest processes used widely in manufacturing to obtain cup shape products. Conventional spinning is the technique that produce axisymmetric part or component over rotating mandrel with the help of rigid tool known as rollers. The shape of roller is very important parameter for the success of the spinning process. This paper datils about using ball shaped rollers as forming tool in conventional spinning process experimentally. The experimental work was carried out on the center lathe machine as forming machine, the spinning tool or spinning rollers was installed on a dynamometer replaced the tool post while the mandrel was mounted on the lathe chuck. The spinning tool in this work consists of three rollers performing the conventional spinning. The set of rollers is mounted on jaws of lathe chuck which working as a holder for the spinning tool parts. The experimental work was conducted in order to test the proposed tool and investigate the influence of the main conventional spinning parameters (mandrel rotational speed, axial feed and blank diameter or spinning ratio) on the process forming load and the product quality. The response of the product quality and required load to process parameters such as rotational speed (76,150, 230 and 305 rpm), axial feed (0.08, 0.15,0.3, and 0.6 mm/rev) also examined new rollers in different mandrel diameters 45, 60 and 80 mm. The experimental results showed that, the suggested tool acquired a spinning ratio of 2.17 which is about 35% greater than the announced conventional spinning ratio of 1.6 without any addition to the tool just using the suggested Ball shaped roller arrangement. the mandrel rotational speed, and axial feed rate are the most pronounced parameters, which have great effects on the forming loads during the spinning process.

Titanium is the polymorphic metal whose recrystallization temperature significantly affects its final properties. The area between 850 °C and 995 °C is a very important area from the point of view of heat treatment of titanium alloys. It is a transition area just below the β transition limit. This article deals with the analysis of the influence of thermal loading on the change in tensile strength and fracture behavior of titanium alloys in comparison with thermally unloaded samples. Monitoring of fracture surfaces and description of the internal structure of the material.

The objective of this paper is the evaluation of dimensional and geometric accuracy and surface to-pography of milled parts from plastic. This evaluation was done on 10 samples from various thermo-plastics made by extrusion and FDM 3D printing. The samples were then milled. One side was milled dry while the other was milled with cutting fluid, which has improved the texture of the result-ing machined surfaces in most cases, for example with printed PLA, where Ra was reduced by 1.8 µm. For determining the dimensional and geometric accuracy, two parameters were chosen, those being distance and parallelism. For evaluating the surface topography, 4 parameters were measured using 2D profile roughness and 3D surface texture. The surface of the prints was greatly improved by machining. The paper ends with practical recommendations for choosing different plastic materials for applications, requiring high dimensional accuracy and low surface roughness.

The aim of this article is to evaluate the material removal rate (MRR) after wire electrical discharge machining (WEDM) and subsequent characteristics of the machined surface. For efficient processing, the aim is to achieve the highest MRR values but with regard to the preserving of required quality and functional characteristics of the surface. During the electrical discharge of material removal craters occur on the workpiece surface and due to diffusion process here premixed and melted material of fodder and wire electrodes cling. As a result of melting and fast cooling down of the workpiece material microcracks may occur on its surface.

In this study, the process parameters of a vertical shaft impact (VSI) crusher are optimized. Different feed size distributions, material physical properties, and product size distribution requirements are considered to determine the optimal material particle bond cleavage ratio. First, a numerical model is developed to simulate the crushing effect by adopting a CFD-DEM method. Then, the relationship between the crushing effect and the rotor speed, feed size distribution, and feed rate is revealed by analyzing the bond cleavage ratio of smaller-size distribution feed crushing to the specified particle size. The optimized working parameters of the crusher are determined under different feed size distributions. The results show that the feed size distribution of 8 mm, 20 mm, and 40 mm account for 20%, 30%, and 50% of the feed, respectively. Based on the results, it is implied that a feed rate of 120 t/h and a rotor rotational speed of 1800 r/min can be selected for crushing production. When the feed size distribution varies, this method can also be used to select a suitable feed rate and the rotor speed for crushing production. Overall, this study guides for optimizing the working parameters and improving the crushing efficiency.