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The presence of reinforcing particles SiCp seriously affects the cutting surface quality of SiCp/Al materials.In this study, different machining parameters were tested to obtain good surface quality, and the surface quality of SiCp/Al alloy material under different milling parameters was studied by using the surface profilometer and scanning electron microscope to explore the effect of cutting pa-rameters on surface quality. The results showed that the Surface roughness value increased with the increase of feed rate and milling speed, and milling speed was the dominant factor in the microstruc-ture evolution of the machined surface. In addition, an exponential model related to feed rate and milling speed was constructed.

Parting-off stands as a fundamental method of turning, involving the cutting of the workpiece. The tool is most frequently a replaceable insert secured in a clamping bed. A pivotal set of observable metrics that ascertain the efficacy of a tool and its appropriateness for machining a specific material under defined cutting conditions is its durability. These durability parameters need to be determined for all new tools to ensure optimal performance and application in various machining scenarios. The primary objective of this research was analysis of the wear experienced by replaceable cutting inserts within the realm of parting technology. There were three distinct variants of replaceable cutting in-serts, all produced by esteemed manufacturer Dormer Pramet s.r.o. These cutting inserts were ap-plied in the parting process, consecutively machining two materials: bearing steel 100Cr6 and stainless steel 316L. The study not only encompasses the description of the cutting test procedure but also involves the meticulous execution of measurements and the subsequent analysis of the data procured from experimental activities. In the final phase of study, additional analyses are outlined to uncover the factors contributing to variations in certain obtained results. Those analyses, such as material or tool coatings analysis, provides more information about interplay between replaceable cutting inserts and the specific materials subjected to parting processes.

Binderjetting technology works on the principle of line injection moulding, using metal powder and liquid binder as input material, which is uniformly applied by print heads to the previous layer using a nozzle. By successively applying each layer, the desired shape of the designed component is obtained. The technology offers a large number of advantages which include the possibility of using any printing powder that may contain functional graded materials. Furthermore, it is a green manufacturing technology where we can reuse unused metal powder in the next printing cycle after following the prescribed process. As a result, we characterize this technology as a near-waste-free production of metal parts. The research aims to analyse the impact of different orientations of printed parts within the workspace on the mechanical properties of the resultant components. Additionally, the study aims to compare these mechanical properties with the specifications recommended by the metal powder manufacturer and findings from previous research studies. Based on the experimental measurements carried out, we can conclude that the influence of the orientation of the parts in the workspace has only a minimal effect on the mechanical properties of the manufactured parts.

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.

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.

Hydrogen embrittlement involves the interaction between hydrogen and the microstructure of metals, which can lead to an alarming loss of mechanical properties. For advanced high-strength (AHS) steel S960MC grade, which finds application in fields ranging from heavy machinery to construction, understanding this phenomenon is important. The material's complex crystalline lattice, carefully engineered to maximize strength, becomes vulnerable in the presence of hydrogen. The sources of hydrogen that can lead to embrittlement of steel are various. From the exposure of steel to hydrogen during production processes to the absorption of hydrogen from the environment. After the absorption of hydrogen into the material, hydrogen atoms diffuse in the microstructure and look for places with high stress concentration (cracks, inclusions, grain boundaries, etc.). In these regions, atomic hydrogen disrupts interatomic bonds, weakening the material and making it susceptible to embrittlement and subsequent complete failure of the component. This research is focused on how the change in current density affects the hydrogen embrittlement of AHS steel S960MC during hydrogenation. It was found that the mechanical properties of steel decrease at a lower current density, but not to the same extent as at a higher current density. Thus, it can be said that the change in current density influences the hydrogen embrittlement of S960MC steel.

The propagation and velocity of the deformation wave in the thin isotropic plate is investigated. The deformation is induced by the stroke of impact body onto the facial surface of the plate. The plate is supported perpendicularly. The excitation of the plate oscillation is initialized by a unit force (Heavi-side’s jump). The impact body has a rounded facet by radius c = 2.5 mm. Hook's material model and Kirchhoff’s and Flüegge’s geometric model have been investigated. The analytical solutions for both models are presented. The MATLAB script has been assembled to solve material and geometrical mod-els. The results were compared for two selected points on the surface of the plate. Plate deformation was recorded at two points T1 (at a distance of 20 mm from the impact location on the x axis) and T2 (at a distance of 20 mm from the impact location on the y axis).

Additive technologies are becoming a common part of not only prototype production, but also piece or small series production. However, the choice of technology and material plays a key role in the applicability of the manufactured parts. The most widespread type of additive technology is FFF technology, which consists of applying a fused plastic string in single layers. The resulting mechanical properties of parts produced using this technology depend not only on the material and structure selected, but also on the process parameters used in the printing process itself. This study deals with the production of filament from PLA, which is the primary material. The advantage is its environmental degradability after the end of the life cycle of PLA products. However, the resulting properties of the printed parts may depend on the way the filament is prepared and in particular on the melt temperature during filament extrusion. This study investigates the effect of the produced filaments on the quality of printed parts. It has been shown that the filament production technology has a significant effect on the quality of printed parts.

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.

Hydro-viscous drive (HVD) clutch is a type of power transmission device by using shear stress of oil film. Whether the oil film between friction pair are uniformly distributed is the key factor that affecting the perfor-mance of HVD clutch. However, it is hard to make sure that the uniformity of oil film between friction pair are the same, which can lead to uneven wear problem for the frictional plates of HVD clutch. In order to study the uniformity of oil film of HVD clutch, the distribution regularity of oil films between friction pair of HVD clutch is researched by establishing the mathematics model. and a new HVD clutch with double-piston structure is pro-posed, which can greatly improve the uniformity of oil film of HVD clutch.

This research focuses on comparing the working accuracy of two additive manufacturing processes, Atomic Diffusion Additive Manufacturing (ADAM) and Binder Jetting (BJ). Through the analysis of key characteristics of these processes, we aim to evaluate which one yields better results in terms of working accuracy. ADAM is a process that involves the gradual deposition of metallic materials using a plastic binder, whereas BJ is a process where the binder is applied to powder material, followed by the removal of excess binder. This work conducts a detailed examination of the properties of the ADAM and BJ processes, with a focus on surface texture and microstructure of the resulting objects, the use of optimal technological parameters, and the assessment of dimensional and shape accuracy. It is also important to note that the final nature of 3D objects depends on technological parameters such as geometry, orientation, and placement of individual shape specifications. The results of this study are crucial for assessing the accuracy of these additive processes and can serve as a significant basis for selecting an optimal approach in the field of additive manufacturing.

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.

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.

The article deals with the experimental measurement of the load on the cervical vertebrae when driving a passenger car over bumps. The measurement was done experimentally. The load on the human spine was measured in the area of the C7 cervical vertebra and also in the area of the top of the head. Vehicle crossings over speed bumps. The measurement was carried out at different crossing speeds and at different heights of speed bumps. Three-axis acceleration sensors were placed on selected parts of the vehicle and on the human body. The proposed measurement methodology was verified by the conducted pilot experiment for the possibility of conducting further experiments. The results of the work showed that the crew of vehicles in road transport is more stressed than previous scientific findings indicate.

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.

This article explores the significance of microtexturing on cutting tools for improved tribological performance and reduced friction in machining operations. Drawing inspiration from biomimetic structures, the study focuses on laser surface microtexturing and evaluates its impact on cutting forces and tool wear. Experiments involve microtextures of dots with a specific emphasis on a fiber laser-processed pattern. While long-term tests reveal the formation of negative protrusions on the textured tools, reduced variability in cutting forces suggests potential benefits for stable machining processes and increased tool longevity. The findings underscore the intricate relationship between microtexturing patterns and tool performance, offering insights into the broader implications for energy-efficient machining.

The polyamide PA6 composites reinforced with carbon fibres (CF) are widely studied due to their properties and their high strength to weight ratio. Good adhesion between a filler and a matrix is es-sential for enhancing properties of a resulting composite. This study investigates the effect of the short CF content and the used CF treatment on mechanical properties of the PA6-CF composites. The composites were subjected to tensile, flexural, compression, hardness and Charpy tests as well as dynamical mechanical analysis. An atomic force microscopy was employed to investigate topography of the CF and the composites. Initially, the properties of the composites were improved through the oxidation of the CF in HNO₃. Subsequently, to further enhance these properties, the oxidized CF were grafted with nano-SiO₂. The CF content in the tested composites varied from 10 wt% to 60 wt%. The most significant improvement of the tested properties was observed at the CF content of 40 wt%.

The present paper discusses important aspects of residual stress measurements in forged shafts with defects using the X-ray method. A random population of shafts was selected for the study, for which, depending on the type of rolling process, turning was performed, measuring stress changes after successive machining passes. In the forged shafts studied, the existence and location of internal defects were identified using computed tomography. The impact of internal defects on the stress distribution on the surface of the machined workpiece was observed. It was observed that the use of the X-ray method to measure residual stresses makes it possible to determine the state of stresses and their distribution, which is crucial for the safety and durability of shaft-type parts, and allows the impact of a defect on the distribution of residual stresses to be identified. On the basis of the results obtained, it was observed that there is a correlation between the occurrence of internal defects in forged shafts and the distribution of residual stresses in characteristic sections along the length of the shaft after machining

Nickel-based superalloy is a kind of metal material that is widely used to manufacture high-temperature parts in the fields of aviation and aerospace, but it is also a typical difficult-to-machining material. The precision cutting of nickel-based superalloy has always been an important manufacturing problem. Based on the tests of conventional drilling with three kinds of twist drills, the machinability of Inconel 718 was evaluated comprehensively by drilling force, tool wear and machining quality, and the cutting tools suitable for drilling nickel-based superalloy were chosen. Then the experiments of peck-drilling for Inconel 718 were carried out, and the process effect under different peck depth Q was deeply researched. The results showed that the HSS-Co (high speed steel with cobalt) twist drill can meet the needs of low-speed drilling of nickel-based superalloy, while the coated carbide twist drill has better service performance. The drill tip structure of dual clearance angle is beneficial to decrease the cutting friction and improve the machining accuracy. Compared with conventional drilling, the peck-drilling can reduce the cutting force and improve the dimensional accuracy and surface quality. However, it is very important to choose a suitable peck depth Q for fully exploiting the advantages of peck-drilling.

With the development of welding technology and the improvement of automation level, welding robots are playing an increasingly important role in industrial production. However, during the welding process, due to factors such as material characteristics, welding parameters, or improper processes, defects may appear on the surface of the workpiece, which may reduce the quality and service life of the workpiece. In order to solve this problem, this article used frequency domain feature extraction and nearest neighbor classifier in workpiece detection algorithms under machine vision technology to extract and classify surface defect images of workpiece, and studied the detection method of welding robot workpiece surface defects. The research results indicated that, under the same other conditions, the accuracy of machine vision technology was over 90% for all five different defect types, while the accuracy of traditional technology was between 75.5% and 84%. The performance of machine vision technology was far superior to traditional technology, indicating that machine vision technology could improve the accuracy of welding robot workpiece surface defect detection methods.

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.

The submitted paper deals with biotribological contact in total knee arthroplasty. The goal was to evaluate the influence of the metal component production technology on tribological parameters in defined environments. The reference sample was a standard available test ball made of the subject material, used in testing tribological properties by the "Ball on Pin" method. The preparation of the experiment consisted in the production of test disks from UHMWPE material and the production of a metal test component with a spherical surface. The condition of the experiment and the basis of this contribution is to compare the properties of conventionally produced metal material against 3D printing. Using the SLM method, a sample with a semi-spherical surface on a cylindrical shank was produced, which was subsequently ground and polished to reflect the characteristics of the standard supplied test ball. The last step was the production of a suitable fixture in order to fit the sample into the tribometer. The so-called dry friction of the heterogeneous Ti6Al4V–UHMWPE pair and the friction in a biological lubricating environment represented by bovine serum were evaluated. The evaluation of the contact surfaces took place using a profilometer and an electron microscope. The coefficient of friction was determined directly from the test device - tribometer.

Even today, there is an ever-increasing demand for the production of aerosol cans made of aluminium, as the cosmetics and other propellant-enriched products stored in them reach more and more people with the development of humanity. The production of these packaging materials is primarily carried out by plastic forming operations. However, during the production process of aluminium aerosol cans, tools with a defined edge geometry also perform cutting operations. The processes taking place here affect the quality of the final product. In this paper, the procedure and results of finite element modelling of the flange turning of aluminium aerosol cans is presented. The structure of the finite element model is introduced, as well as the possibilities of considering the peculiarities of the process. Since the used pure aluminium (Al99.5) is considered a difficult-to-cut material, the machinability of aluminium and its alloys is also discussed.

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.

The paper focuses on proposing a method for implementing key performance indicators (KPIs) to assess the effectiveness of manufacturing processes. For the evaluated processes of precision parts machining, the share of non-conforming products was proposed as a KPI, evaluated as both an exter-nal and an internal indicator. The external indicator EXTppm expressed the quantity of faulty prod-ucts to the volume of production. Its monthly development during 2022 was evaluated. The internal KPI represented the internal share of non-conforming products INTppm during 2022 which was re-lated to the order of part A. Towards the conclusion causes for not attaining the targeted KPI values are pinpointed, and recommendations are put forth to enhance the productivity of manufacturing processes.

There are currently many control methods for linear motors, and the focus of controlling the motor should be different for different application needs. In general applications, simple PID control can meet the application requirements, but in precision motion situations with high requirements for motion accuracy, response speed, and stability, PID control is often difficult to achieve satisfactory control results, which requires the application of more advanced control strategies to complete. At present, combining multiple control algorithms and concentrating the advantages of each algorithm while trying to overcome each other's disadvantages has become a major trend in the development of motor control theory. High speed, high efficiency, high precision become the development direction of the current numerical control equipment, linear motor because of its unique performance, now widely used in a variety of precision positioning occasions. Aiming at the requirements of high speed response and high precision of linear motor, the linear motor system is designed based on LabVIEW software and NI acquisition card, including hardware composition and software algorithm. In the LabVIEW simulation environment and the actual control system, the conventional PID algorithm and fuzzy PID algorithm are used to control, and the control results are compared. The experimental results show that compared with the PID control, the fuzzy PID algorithm has obvious advantages in improving the control accuracy, anti-interference ability, reducing the overshoot and improving the system response speed.

To meet the need of high-speed steel roll grinding, a hydrostatic lubrication system for high-speed precision roller grinding head is designed and the dynamic performance of the system is simulated and analyzed in this study. The hydrostatic lubrication system was designed according to the lubrication characteristics of the eccentric sleeve and thrust bearing of the high-speed precision roller. Then the mathematical models of the main components of the system were established. And according to the schematic diagram of hydrostatic lubrication system, the dynamic performance of the lubrication system at high speed was simulated and tested. The simulation and experiment results show that the lubrication effect of the eccentric sleeve static chambers and thrust bearings is good, and the designed hydrostatic lubrication system is feasible.

The automotive industry is one of the most dynamically developing segments of the industrial production worldwide. The introduction of still increasingly stringent emission limits for newly developed cars forces car producers to still reduce the fuel consumption of cars. One option is to use hybrid drive units in combination with a redesign of the automobile body while maintaining the highest possible level of vehicle safety. For these reasons, the automotive industry has been increasingly demanding to apply and process low density (lightweight) alloys, including aluminium-based alloys. These materials are subject to high demands both in terms of mechanical properties and technological workability in the mass production process. The utilization of mathematical modelling (numerical simulations) of production processes is now one of the standards in all phases of design and production the car-body and allows the implementation of variable designs in a relatively short time scale and the detection of potential production problems as well. In this paper, the influence of the kinematic hardening model on the accuracy of spring-back prediction is shown in comparison with the commonly used isotropic hardening model. For deformation analysis, a simple workpiece having ?U-shape? of EN AW 6111 material was used. Such aluminium alloys is used for production car-body panels in the automotive industry. Achieved accuracy of numerical simulation results is evaluated by the comparison shape obtained by numerical simulations and shape of experimentally bended workpiece.

This paper describes a search for an optimal organization of the drying agent motion in the convection dryers. An overview of the main methods on how to reduce the energy consumption for the convection drying of the disperse materials is presented. The use of the multistage shelf apparatuses with a differential thermal regime for the con-vection drying of the disperse materials is justified. The work contains the results of a computer modeling on de-termining the drying temperature and moisture characteristics with the use of various methods of the organization of the drying agent motion. The model is realized implementing the author?s software product Multistage Fluidiz-er?. The software product enables to automatize calculation simultaneously by several optimization criteria and to visualize calculation results in the form of 3D images. The engineering computation of sectioning devices meth-odology with fluidized bed of particles is based on the calculation results. The automated calculations results give a base to design industrial drying device with a differential thermal regime.

Trusses are commonly used structure in industrial buildings, warehouses, bridges, transmission tower etc. The analysis of the truss structure design is necessary in order to ensure stable and economical system. This paper presents application for computing planar truss structures that was programmed in environment of MATLAB App Designer using finite element method (FEM). App Designer is programming environment used for creating computing applications with graphical user interface (GUI). The created application for trusses allows users to create geometrical model of the truss structure and input material data, perform static analysis, modal analysis and to optimize truss structure in order to minimize its weight. To ensure accuracy of results, test calculations was performed using commercial software and compared with results from the created application.