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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.

Molten salt reactors are one of the technologies developed under GEN IV nuclear research. The mol-ten mix of LiF and BeF2, LiF, NaF nad KF, or NaBF4 and NaF act both as a reactor coolant both in primary and secondary loop. The combination of molten fluorides and high temperature creates high-ly corrosive environment. The aim of this work was to test corrosion resistance of Inconel 800HT alloy in molten FLiNaK, FliBe and NaBF4-NaF mix. The testing tube was filled with salt mixture and heated to 600-725 °C for a total of 1800 hours. The material exposed to NaBF4-NaF mix shoved mild corrosion attack on grain boundaries. Samples exposed to FLiNaK salt were more damaged, largely the part above the salt surface. The intergranular corrosion was also observed, more severe than in the case of NaBF4-NaF environment. Corrosion in the FLiBe salt caused depletion of alloying metals from the material’s surface. In all cases was dissolving of Cr into the melt identified as the main mechanism. The corrosion was accelerated by impurities in the salt mix, mostly water forming hydrogen fluoride gas in combination with insufficient seal of the testing tube.

Wire electrical discharge machining (WEDM) was employed to process thin-walled, multidirectional carbon fiber-reinforced silicon carbide (Cf-SiC) composites. This study investigates the effects of key WEDM parameters, including gap voltage (Vg), pulse on-time (Ton), pulse off-time (Toff), and wire electrode type on material removal rate (MRR) and surface roughness (SR). All experimental planning, data analysis, optimization, and result visualization were conducted using MATLAB software. Results indicate that using CuZn50-coated wire electrodes increases MRR by 11% compared to CuZn37 bare brass wire. Scanning electron microscopy (SEM) confirmed the inverse thermal expansion-based material removal mechanism, revealing surface defects such as fiber fractures, interfacial detachment, craters, and micro-cracks. Surface roughness, as indicated by 3D topographic measurements was found acceptable with an average Ra between 2 and 3 μm. Overall, WEDM proves effective for machining Cf-SiC, especially for complex geometries such as holes, grooves, keyways, and splines when appropriate electrodes and parameters are applied.

The "baby hanging basket" five-axis precision machine tool (BHBFPMT) studied in this study is mainly used to process open impeller and closed impeller in aerospace field. However, the linkage accuracy (LA) measurement of five-axis machine tool is one of the important detection means to ensure the tolerance requirements of precision parts. The mathematical model of linkage accuracy (LA) of "baby hanging basket" five-axis precision machine tool (BHBFPMT) was established. The accuracy of X, Y, Z, B and C axes was measured, respectively. Combined with the measurement results, a pulse compensation method was proposed to compensate the accuracy. The linkage accuracy of the machine tool was analyzed by the machining and precision measurement method of "round-rhombic-square" trial cutting parts. The results show that: (1) In single-axis measurement, the positioning accuracy of X, Y, Z, B and C axes are 0.00096 mm, 0.00261 mm, 0.00173 mm, 0.0113 mm and 3.62 '', respectively. (2) When the pulse changes of B axis and C axis are 1048630 and 1048596, respectively, the positioning accuracy meets the accuracy requirements of "baby hanging basket" five-axis precision machine tool. (3) By measuring and analyzing the accuracy of "round-rhomb-square" test pieces, the linkage accuracy of "baby hanging basket" five-axis precision machine tool is less than 20 μm, which meets the factory standards and precision requirements of machine tool.

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).

Ball-section raceway groove and narrow groove ring (BGNGR) is a complex part of bearing rings. The mandrel for the forming of the narrow groove will push and press the metal and lead to instability of the rolling process. Therefore, the effect of the narrow groove on the metal flow is investigated. Two methods for BGNGR rolling are presented, and by deducing the dimensional relationship between rectangular blank and deformed ring, the finite element models for both methods are established and simulated in Forge3D software. Method I is proved to be a failure through the finite element analyses of the effect of the narrow groove on the metal flow. Based on the analysis result in Method I, the Method II with appropriate mandrel profile for the going up metal is proposed. The simulated result shows that the BGNGR whose geometry size meets the requirement can be rolled by Method II.

This paper explores the investigation of a natural alloy processed using the rapid solidification tech-nique. The study involves the reduction of manganese nodules through aluminothermy with a 20 wt. % excess of aluminum, followed by further processing of the resulting alloy using the melt-spinning process. The obtained melt-spun ribbons were subjected to a comprehensive analysis, including X-ray diffraction, scanning electron microscopy for microstructure observation, and EDS analysis for local chemical composition. The research unveiled that the rapidly solidified ribbons consist of several key phases, including β-Mn, the Heusler phase Mn2FeSi, and an intermetallic phase (Cu,Mn)3(Al,Si). Im-portantly, the phase composition exhibited notable differences from that of the as-reduced alloy, with a reduced number of phases in the rapidly solidified ribbons. Notably, the phase composition re-mained stable even after annealing, demonstrating the robustness of the rapidly solidified material. Impressively, the material exhibited a remarkable hardness of approximately 800 HV 0.1, even after 100 hours of annealing at temperatures of 500 and 750°C.

Grinding is one of the most important processes in machining precision rotating parts. GF & GT (grinding force and grinding temperature) of single particle in grinding wheel have great influence on surface roughness. This study established the GF & GT models of single particles. Abaqus was used to analyze the coupling between GF & GT of single particle. Combined with grinding parameters (grinding depth and grinding speed), the influence of GF & GT on the range of surface roughness of single particle abrasive was comprehensively studied. The machining and experimental analysis of precision aerospace bearings were carried out through theoretical analysis. The results show that with the increase of grinding depth, the GF & GT in X and Z directions increase gradually. However, the grinding temperature does not increase linearly with the increase of grinding depth. Compared with the grinding speed, the influence of grinding depth on the grinding force in Y and Z directions is much greater than that in X, which is 7.38 times and 5.81 times of the grinding speed, respectively. Grinding depth has the greatest influence on surface roughness, which is 3.6 times the grinding speed. When the test speed is constant at
60000 rev/min, the bearing temperature is between 30 °C and 65 °C and most of them are within 44 °C. The test data meet the requirements, and all indexes are controllable. The above conclusions provide a theoretical basis and selection of process optimization parameters for grinding precision rotating parts.

An application of external fixator is a surgical method for the treatment of large bones fractures. This method has been proposed already a century ago, but despite the extensive development of science and technology, the fixator is often used in the original state of the proposal. [1] Therefore the patient and surgeons are dissatisfied with high weight and poor mobility of fixator during surgery and healing process. [2] Due to this fact it is necessary to apply new 3D technologies into this field of orthopedics and thus improve the current state of this tool. [3] In an account of this information, the 3D model of a new composite external fixator was created. In the research, the composite fixator was analyzed by the finite element method (FEM). Based on the results of FEM and the surgeon's requirements, the composite fixator was further improved and the final results show that the composite fixator proposed by the FEM is able to transfer the applied load from a patient. Therefore the data indicates that the implementation of composite material will further improve patients comfort, the healing process and the precision of surgery. Based on this fact, the mold has already been manufactured and the process of completing the product has started.

The tempering procedure of quenched 54SiCr6 spring steel was analyzed using continuous heating dilatometry, isothermal dilatometry, metallography, and hardness measurement. The dilatometry was performed on four different steel modifications with graduated Si content and with two levels of Cu. Metallography and hardness measurement were analyzed only on samples with one Si level. Two types of tempering procedures were compared in this experimental program. The first one was sim-ple one-step tempering, the other was a special procedure of strain assisted tempering (SAT), which includes double tempering and strain applications between tempering. A dilatometry analysis with the support of metallography contributes to the material behaviour explanation, which is considerably different in both processing cases.

The work deals with the creation of 3D model of a disc brake of a personal vehicle, followed by a simula-tion of thermal and strengh analysis during car braking in the SolidWorks program. The disc brake is made of a gray cast iron, the most common material for this application. Cast iron discs offer excellent performance, making them suitable for various types of vehicles. The deformation of a brake disc was analyzed by using the program SolidWorks, where the first a simulation of the thermal load was per-formed, the aim of which was to determinate the temperature distribution on the brake disc and display the temperature rise during braking. In the next part, the simulation of strength deformation was carried out, and thus determination of the ther-mal load effect of the brake pads on the brake disc.