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The paper deals with the solubility and influence of the melting method of alloying elements (Zr, Mo and Sr) on selected properties and structure of the hypoeutectic aluminum alloy AlSi5Cu2Mg. Alloy-ing elements in the form of master alloys (AlZr20, AlMo10, and AlSr10) were melted in two different methods. The first method consisted in melting the master alloy together with the batch material in an electric resistance furnace, the second method consisted in separately melting the master alloy in an induction electric furnace and then introducing the master alloy into the molten batch. The presence of alloying elements led to an increase in the porosity in all experimental alloys, which negatively affected the resulting physical and mechanical properties.

Robotics plays a key role in industry and its use continues to grow. Robots are used in many industries to increase efficiency, productivity, and safety of work processes. This manuscript focuses on the spatial calibration of collaborative robot arms using appropriate statistical tools. Nowadays, there are many special programming languages, simulations or virtual realities (VR), which in most cases perform calibration using matrix relations. The mathematical-statistical solution is not solved very often, and the use of linear relationships is valid only in certain parts of the workspace of the collaborative robot. The purpose of this article is to demonstrate how to find a suitable statistical method that would respect the wear of the arm mechanism in predefined positions based on the requirements of ISO 230-2:2015. Based on these measurements, it is possible to assume that optimal solutions can be obtained using a polynomial regression function. This optimization method will be searched using the Newton and Markwartel methods.

PolyJet technology, based on the printing and photopolymerization of model material, is currently, along with stereolithography or 3SP (Scan, Spin and Selectively Photocure), the most commonly used rapid prototyping method based on optically active resin. The article presents the results of torsional strength tests of samples made of optically active resins VeroDentPlus-MED690, VeroClear-RGD810, and Rigur-RGD450 by Stratasys in PolyJet technology. The samples were prepared in HQ (High Quality) mode with a layer height 0.016 [mm]. The tests included a static torsion test using a specialized research stand by the Department of Mechanical Engineering of the Rzeszów University of Technology. The scope of research significantly expanded the standard procedure, which complements the material data available with significant functional parameters due to the use of models. The results of the torsional strength analysis determined in the research process can be used to define the potential application area of the materials in question - optically active resins and their processing techniques for the production of parts subject to complex loads, i.e. machine shafts, clutches, and gear hubs.

This article deals with the modification of surface properties of austenitic steels using laser shock peening (LSP) technology. This technology introduces residual compressive stresses into the surface layer. These stresses improve the technical properties of the material not only by affecting the re-sistance of corrosion cracking under stress. The aim of the work was to influence the austenitic steel 08CHN10T by LSP technology, to perform a corrosion test in a boiling MgCl2 solution and the sub-sequent evaluation of these tests. Furthermore, the hardness was measured of the peened part of the material by LSP technology and unpeened part.

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.

The geometric accuracy of a machine is primarily determined by the accuracy of assembly, manufactur-ing, and overall setup. Standardized procedures for assessing geometric accuracy are established and detailed in delivery protocols for various types of machining machines. To effectively monitor and ana-lyze machining machine errors, the most suitable approach is to construct a comprehensive error balance that accounts for the overall performance of the machine. This error balance methodology, a tool within the realm of system analysis, is utilized for predicting and managing systemic errors. The errors ob-served in machined components are intimately connected to the errors present in the machining ma-chines themselves. These errors are further intertwined with the design and physical properties of indi-vidual machine components, as well as their interactions. In the case of multi-axis machines, they col-lectively determine the overall accuracy of the produced components. The objective of this study is to analyze machining machine errors using the Renishaw XL-80 laser interferometric system. The findings of this study reveal that errors in machining machines can also be the result of the dynamics of the cut-ting process, which may have a significant impact on accuracy.

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.

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.

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.

Today's machining requirements cannot be met without the right tool materials. An ideal universal tool material should combine the highest abrasive wear resistance and hardness with high strength and good toughness, while being chemically inert to the workpiece material. Despite the intensive development of materials sciences the fundamental contradiction between hardness, which guaran-tees resistance to abrasive wear, and toughness, which determines impact and fatigue strength, has not been satisfactorily resolved on a global scale. This paper presents the results of tribological wear testing of commercial cutting inserts of S20S, U10S and CC6090 grades. Chemical composition, den-sity, hardness and tribological wear were determined using the ball on disk method. The analysis of the laboratory tests showed that the S20S, U10S and CC6090 cutting inserts have high resistance to abrasive wear, the loss of total volumetric mass did not exceed 1%.

A constant tension cable reel based on planetary gear transmission is introduced. The parameters of the mechanism are determined to analyze the speed and torque of the transfer mechanism. The relationship between the thread pitch and cable type show that different cable models require different parameters for the constant tension cable reel. The mechanism is designed to automatically adjust the force required for cable pulling and maintain a constant maximum tension. Then the relationship between the moment and speed of each output shaft is analyzed, and the operation mode of the cable reel was explained. The experimental results show that the proposed cable reel can pull the cable flexibly while providing the required constant tension, without damaging the cable and extending its service life. The pitch of the screw-thread pair is directly related to the required tension of the cable and the cable diameter. If the power supply cable model is different, the parameters of constant tension cable reel are also different.

Today, 3D printed wrist-hand orthoses can be used to immobilize the arms instead of plaster or fi-berglass casts. Typically, 3D arm models for modelling wrist-hand orthoses can be created using a 3D scanning system. Our previous study shows that smartphone cameras and photogrammetry tech-niques can be used instead of professional 3D scanning systems, but the accuracy of the photogram-metric models has not yet been fully investigated. This paper presents the results of accuracy verifica-tion of arm models reconstructed from 2D images captured with a smartphone camera. The forearm and wrist-hand parts of a photogrammetric model were subjected to a virtual inspection by compar-ing them with the corresponding parts of an arm model created with a 3D scanner. In addition, a physical verification was carried out by assessing the contact between the arm of interest and an ac-tual 3D printed wrist-hand orthosis that was created with reference to the photogrammetric model. The test results show that the photogrammetric models achieve the necessary accuracy to serve as reference models for the construction of 3D printed wrist-hand orthoses.

The high-entropy alloy with the composition Al0.8FeCoNiCrCu0.5Si0.2 was produced through a pro-cess in-volving a vacuum arc melting method. Comprehensive characterization was performed through techniques such as XRD, SEM, and TEM. The findings revealed that the alloy primarily con-sists of Fe-Cr and Al-Ni phases, displaying predominantly two body-centered cubic structures. The alloy exhibited a characteristic dendritic cast structure. The alloy predominantly has high-angle grain boundaries accounting for 96.1%. Its grains demonstrate minimal internal strain and reduced lattice anomalies. The alloy showcased resistance with a corrosion current density of 1.4×10-7 A/cm2 and a corrosion potential of 0.28047 V. Post-corrosion examinations emphasized regions abundant in Al and Cu as the primary degradation sites. The addition of Si has further improved the alloy's resistance to corrosion. In terms of abrasion durability, the alloy exhibit-ed a wear scar length of only 1.42 mm, substantially less than the 1.88 mm found in 45# steel, highlighting its enhanced resistance to wear. This wear resistance is attributed to its inherent BCC1 and BCC2 phase structures and the hardness it derives from its unique composition. Owing to its superior traits, this high-entropy alloy presents promising potential for applications, including coatings, and advanced automotive components.

The present work was aimed at studying the effect of a “Slab/Sheet” thickness ratio (SSTR) on the microstructure and mechanical properties of API 5L X70 steel sheets intended for heavy-wall oil/gas pipelines. The 25 mm-thick and 40 mm-thick steel sheets were rolled from the cast slabs of different thicknesses (250 mm and 300 mm) and their mechanical properties were compared. The sheets were subjected to thermo-mechanical controlled processing followed by accelerating cooling, resulting in the structure of quasi-polygonal/acicular ferrite with minor amounts of granular pearlite and martensite-austenite constituents. Increasing the cast slab thickness significantly improved the ductility and low-temperature impact toughness of steel sheets regardless of their thickness. Specifically, a total elongation increased by 3-6 points (up to 26-28 %); an absorbed impact energy (tested at –20 °C) – in 1.5-1.8 times (up to 300-370 J); the DWTT shear area (at –20 °C) – in 1.6-2.1 times (up to 81-91.7 %). The properties advancement under SSTR increase was associated with an additional refinement of ferrite grains and better homogenization of cast structure under deeper hot deformation.

With the rising demand for efficient, lightweight support structures in high-energy physics experiments, advanced manufacturing techniques and material optimization are key to achieving high-performance designs. This study focuses on the application of generative design and topological optimization in the development of support structures for the FCC muon spectrometer. By leveraging these methods, we maximized material efficiency and minimized weight while ensuring structural integrity and meeting strict design constraints, including non-magnetic properties, minimal deformation, and high precision. A detailed evaluation was conducted with respect to manufacturing techniques that balance perfor-mance with cost-effectiveness, resulting in multiple design iterations of optimized truss configurations. This approach demonstrates the potential of modern manufacturing technologies in enhancing the structural and economic viability of components for large-scale scientific equipment.

In the realm of engineering the quest for optimization is ceaseless. This article explores the intricate relation-ship between cubic equations and the practical world of production technologies, unearthing the profound connections that underpin mathematical symmetry and its role in engineering. Cubic equations, often arising in the analysis of mechanical systems, electric circuits, and robotics, serve as indispensable tools for under-standing and enhancing real-world applications. This study delves into the methods for finding the roots of cubic equations, shedding light on the vital role of mathematics in engineering and manufacturing technology.

Silicide – aluminide composites could be considered as potential tool materials, because of high wear resistance and thermal stability. Recently, the alloys based on iron aluminide and silicide were tested, but they found to be very brittle due to the occurrence of brittle Fe-Al-Si ternary phases. On the other hand, in TiAl-Ti5Si3 composite, no ternary phase was formed during sintering, even though it can be expected based on thermodynamics. Therefore, this paper aims on finding the way how to test poten-tial interaction between silicide and aluminide phase during preparation of these composites.

In order to improve the processing efficiency and surface quality of the piston avoidance pit, reduce labor costs, and make the processing of the piston avoidance pit meet the modern production re-quirements, it is realistic and feasible to combine Pro/E and Mastercam software to complete the processing of the piston avoidance pit. Two different kinds of piston pits are selected for machining, and the 3D model of the piston pits is established by Pro/E software, and the process preparation and parameter setting are realized by Mastercam software, and the NC machining simulation is con-verted into NC code to realize the machining of the piston pits; two different surface finishing meth-ods are used in Mastercam software to complete the machining of the piston pits. The two different surface finishing methods are analyzed for their effects on the programming of the piston avoidance pit, and a method to improve the efficiency and surface quality of the piston avoidance pit is derived to further improve the machining method of the piston avoidance pit and provide reference for the subsequent machining of the piston avoidance pit.

This article explores the effect of cryogenic temperatures on the properties of cobalt alloys, specifically Stellite 6 and Stellite 12. These alloys are commonly used in applications that require resistance to me-chanical, thermal, and chemical wear. In this study, the focus is on the valve seats for internal combus-tion engines, which are made from cobalt alloys and undergo a freezing process before assembly into the cylinder head. The purpose of freezing is to reduce the diameter of valve seats, making them easier to fit into the cylinder head. However, the length of time spent in freezing can significantly affect the hardness and tribological characteristics of the material.

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.

Recently, engineering polymers like PMMA have increasingly replaced traditional materials in industry where feasible, with CO2 laser cutting gaining attention for its high quality and speed in processing these materials. Achieving precise cuts is crucial for product accuracy, with kerf width serving as a key quality attribute to ensure quality and functionality of the final product. This study focuses on the im-pact of three critical process variables: stand-off distance, laser power, and cutting speed, on the kerf width in CO2 laser cutting of PMMA. Through a full-factorial experiment, the process parameters are systematically varied to understand their individual and interaction effects on the cutting process. The kerf width is measured as an indicator of precision using an optical microscope to evaluate the quality of the laser cuts. To address the non-linear relationships between these process parameters and kerf width, several machine learning models were utilized. Performance comparisons indicated that the Artificial Neural Network (ANN) model provided the highest accuracy, with R² values of 0.98 for the validation dataset and 0.95 for the testing dataset. The optimized ANN model offers a robust tool for parameter optimization, facilitating the determination of optimal settings to achieve the desired kerf width while ensuring productivity.

The aim of the article was to present the results of cutting temperature measurements during trochoidal milling. The investigated material was 145Cr6 (50 HRC). Three trochoidal paths were used: A– described by movement circle, B– described by arcs and straight lines, C– described by short lines between a lot of points. The main conclusions include: similar values of cutting tem-peratures when using paths A and C (differences between the values of about 5%), the use of a trochoidal path type B enables a significant reduction of the cutting temperature. During tro-choidal milling, the maximum temperature values were about 420ºC.

Industry 4.0 needs to have a digital representation of the real manufacturing and assembly processes to foresee the effects of modifications on equipment, tools and processes. Assembly processes often use adhesive to keep together the components because it has many advantages. The simplest example of adhesive assembly is a single lap joint. In the literature, the attention is focused on nominal adhesive assemblies, that do not represent the real products and that are tested to evaluate the product’s strength. Therefore, the obtained mechanical performances are far from those connected with the real products. The present work takes into account the geometric deviations of a single lap joint, as the adherends’ misalignment, due to the manufacturing process and used equipment on its strength. A numerical tool of the literature was modified to deal with adherends’ misalignment to estimate both the tensile and the bending strength. The numerical results were validated through experimental tests. The developed numerical model shows a very low deviation from experimental results. The original contribution of this work is that the developed numerical model simulates the adhesive process of a real joint with adherends’ misalignment and not of its nominal geometry; thus, providing a tool more useful in optics Industry 4.0 to represent a process closer to the real.

The application of cellulose (CEL) as a filler in elastomeric composites (ECs) was studied, with cellulose examined in its untreated form (RAW), after DCSBD plasma modification, and ozone pre-treatment. Changes in surface fluorescence demonstrated that DCSBD plasma-modified cellulose achieved better dispersion in the elastomeric composite mixture, which also showed improved strength and elongation in static tensile tests. DMA analysis confirmed changes in visco-elastic properties, with DCSBD plasma-modified cellulose altering the glass transition temperatures of the Elastic and Loss modulus, as well as Tan Delta. SEM microscopy did not conclusively demonstrate the reinforcing effect of plasma-modified cellulose. Small property changes were observed with ozone pre-treated cellulose, similar to the unmodified cellulose composite mixture (NR).

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.

This paper describes β-Sn to α-Sn transformation in its initial phase. This process is also known as a tin pest and currently it causes problems mainly in the field of soldering materials. To avoid misrepresenta-tion of the results of artificial ageing of the samples; we have decided to use historical materials for our study. A sample from historical organ pipes was indented by naturally formed α-Sn polycrystalline parti-cles by the load of 1 kg. The sample in the initial state was observed by SEM and analysed by EBSD mapping. The position of inoculator particles was documented again by SEM observation. Subseqently, the sample was freezed at -50 °C. The evolution of cracks started after 2.5h in the vicinity of indented α-Sn particle. After 5 h of freezing, new cracks were observed also in the untouched parts of the sample. The crystallografical interconnectedness was not proven for polycrystalline samples.

By achieving the accuracy and roughness requirements imposed on the connecting surfaces of machine components –the topography created during machining – it is guaranteed to meet the operational requirements. We cannot ignore the fact that if connected milled plane surfaces move in different directions relative to each other during operation, there may be different contact conditions caused by the unevenness of the topography. The direction-dependent roughness irregularities and functional characteristics of the topography are not sufficiently explored, thus in this work we examine the roughness and its deviations by assuming displacements in different directions compared to the feed motion during operation. The inhomogeneity of the topography is analyzed with a symmetrical milling setup on a face-milled surface, with profiles measured in plane sections parallel to and in 8 other different directions from the feed. The degree and distribution of deviations of the recorded roughness profiles, the selected amplitude and functional roughness values are examined at several points of the measurement planes.

Based on the high hardness, poor thermal conductivity, and easy detachment of graphite in cast iron materials. Traditional rough machining inserts cannot achieve good machining surface quality, while the use of precision machining inserts results in rapid tool wear due to excessively sharp rake angles, limiting feed rates and reducing machining efficiency. In order to solve these problems, this paper proposes a method of cutting cast iron with coarse and wiper insert mixed cutting tools, aiming to improve the surface quality of machining and enhance machining efficiency. By studying the mecha-nism and cutting experiments of the wiper inserts, it was found that it improved the surface quality of cast iron and analyzed the reasons for tool wear. By controlling the integrity of the precision ma-chined surface of cast iron, the aim is to establish the basic theory and key technologies for the pre-cise and efficient manufacturing of high hardness materials. Improve the surface quality of cast iron processing, extend tool life, and improve processing efficiency.

Laser cladding technology, a novel surface modification technique, is widely employed in tasks such as metal surface strengthening and repair. However, the quality post-cladding often falls short of usage requirements, harbouring defects like cracks and pores. In pursuit of a crack-free cladding method, surface texture technology is integrated with laser cladding technology to establish a multi-field coupled numerical simulation model. This model investigates the temperature, stress, and fluid fields during laser cladding with and without texture, aiming to identify the optimal cladding parameters. The results indicate that the optimal cladding parameters are a laser power of 1200 W, a scanning speed of 7 mm.s^-1, and a spot radius of 2 mm. In comparison with cladding without texture, the minimum temperature has increased by approximately 50 %, while the peak temperature has remained almost unchanged. The maximum residual stress of the cladding layer without texture is 369.46 MPa, whereas that of the cladding layer with pre-set texture is 338.46 MPa, representing a reduction of approximately 8.39 %. The bottom of the cladding layer has decreased by about 29.1 %, effectively enhancing the mechanical properties at the metallurgical bond of the cladding layer. The pre-set texture induces a decreasing trend in the flow velocity inside the molten pool, eliminating the double-vortex effect, and resulting in a more uniform temperature distribution within the molten pool, consequently reducing the residual stress of the cladding layer. This paper employs multi-field coupled numerical simulation technology to monitor the internal state of the molten pool, offering insights for enhancing the quality of the cladding layer in subsequent endeavours.

This paper presents the results of nanoscratch tests conducted on adhesive bond thickness, analyzed in terms of material property heterogeneity within adhesive bonds. Nanoscratch tests were performed on adhesive layers made from rigid and elastic adhesives with thicknesses of 0.05 mm and 0.1 mm, under constant load conditions. Penetration depth and residual depth results were analyzed for potential varia-tions in hardness along the adhesive layer thickness. The findings clearly indicate some differences in the material properties of adhesive layers within bonded joints. These results can also be correlated with the phenomenon of apparent Young's modulus, which involves changes in modulus values across the adhesive bond thickness. These findings are crucial for understanding phenomena affecting the consti-tution of adhesive joints, enabling enhancements in their reliability and durability.