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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.

Reinforcement steel rebar is produced by several ways but most importantly the tempcore process. Due to mass production in steel rolling plants, the rebars are gathered after tempcore process at a specific temperature in bundles stack in the warehouse. The bundling temperature varies from 200 to 300 o C. The rebars need relatively long time, up to one day, to reach the room temperature in the bundles stack. This work investigates the effect of prolonged ageing time on the rebars mechanical properties after the tempcore process of both ageing in bundle and designed artificial ageing. The results of mechanical properties of ageing in bundle compared to the artificial ageing were found to be in good agreement. The yield and tensile strengths were found to decrease by 6.3 and 2.1 %, respectively, due to artificial ageing. However, the elongation and the tensile to yield ratio increased by 17.6 and 4.8 % respectively.

FDM forming 3D printers may encounter problems such as rough printing surface and poor accuracy during operation. This study mainly utilizes the complementary advantages of piston extrusion mechanism, sliding vane pump extrusion mechanism, and plunger pump extrusion mechanism to design a parallel combination of three nozzle extrusion mechanism, and conducts simulation experiments to verify its effectiveness based on temperature distribution data comparison. It basically avoids the irregular voids and faults caused by the thermal phase change of materials passing through the nozzle during the printing process.

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.

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.

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.

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.

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.

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.

The usage of aluminium alloys has an increasing trend in the manufacturing industry in recent years. This fact is connected with their ability to combine their very good properties. Characteristics of aluminium are low specific weight, very good thermal and electrical conductivity, and ductility. However, the major disadvantages are low strength and hardness. Therefore the aluminium alloys are alloyed with the elements, which would significantly improve the properties of aluminium. The machining process of aluminium alloys is influenced by many factors that affect the machinability. These factors are for example process conditions, cutting tool material, cutting tool geometry, cutting environment or the chemical composition of the machined material itself and microstructure of the workpiece. Due to the different structures, the machinability of aluminium alloys and pure aluminium is significantly different. Factors such as chemical composition, precipitates, the number and position of soft particles or the strain hardening degree affect the behaviour between the cutting tool and the workpiece during machining. When machining the aluminium alloys, there are some problems such as the surface quality, micro-geometry, tool wear, the chip shape, built-up edge formation, etc. The article deals with the surface defect investigation after the machining process, when on the surface of the material stay the visible "snowflakes" after the turning operation. These "snowflakes" were documented and were performed analysis and observation to find the cause of these flakes.

This paper deals with the design of a multi-part mould for the production of a carbon fibre medium-large compo-nent. The design and forming of a medium-large component which is defined by a closed structure and has high demands on dimensional accuracy is a very complex process. The goal was to design a simple manufacturing pro-cess for a negative mould. There are many different ways to design and manufacture this type of mould. One pos-sible solution was designed and tested. This paper describes the case study of a carbon fibre monocoque of a small racing car. The first step was to define the requirements of the final product and the negative mould. The next step was to design a multi-part mould with one main parting plane and two minor parting planes and define the number of steps needed to build a negative mould. Another problem is how to define the position of the general anchor points that determine the final product. In this case the procedure of transferring the hole from a positive to a negative mould was defined.

Plastic materials are used in automobile, electrical and electronic applications, agricultural utilization, household and furniture products, and medical equipments. Among various plastic manufacturing process, injection molding is one of the most commonly used and common methods applied for forming plastic products in the industry. The process requires a molten polymer being injected into a cavity of a mold, which is cooled and the product ejected from the mold. During the Plastic Injection Molding (PIM) process, various defects, such as volumetric shrinkage, warpage, weld line and sink mark can occur. This paper presents a method to minimizing warpage defect on PolyPropylene AZ564 via PIM simulation using Moldflow software. The approach was based on Taguchi method.
Through the effectiveness of this proposed method, it is confirmed using simulation by Moldflow software. The effect of the process parameters on the warpage of a motorcycle number plate bracket, is studied using analysis of variance (ANOVA). From the ANOVA, the significant parameters affecting the process are holding time, holding pressure and injection pressure. The result of the Taguchi prediction shown that minimum warpage is 1.078 mm, which is 7.14% and 9.09% different from the simulation result and experiment, respectively.

During the last years, due to the dynamic development of the non-contact measurement methods, there has been observed still increasing number of their applications in various fields - not only in the engineering industry. E.g. from the dimensional quality point of view, knowledge of real 3D data of a given part is truly very important. There are several options for obtaining these data such as the usage of optical 3D digitization or computed tomography (CT). However, within the mutual comparability of such data, it is very important to know not only the accuracy of acquiring 3D data, but also e.g. possibilities of these systems in terms of own measurement. In the paper, a specially designed part containing various convex and concave shapes was measured by using two different systems (ATOS TripleScan optical 3D scanner and METROTOM 1500 G2 CT scanner). The resulting scanned models were then compared not only in terms of dimensional accuracy, but also in terms of quality and detail of the obtained data or the time required to prepare the measurement and its implementation.

This paper describes series of studies concerned with welding of Sc-modified AA2519 at the Military University of Technology. The modification of AA2519 alloy contains a higher concentration of scandium and zirconium and it has been developed in The Institute of Non Ferrous Metals, Light Metals Division in Skawina. The examination involves friction stir welding (FSW) and laser beam welding (LBW) of 5 mm thick AA2519-T62 extrusion. FSW process parameters were: 600 rpm tool rotation speed, 100 mm/min welding velocity, 4.8 mm depth plunge, and MX Triflute tool type. The used LBW parameters were as follows: 3.2 kW laser power, 1.1 m/min welding velocity, 0.2 mm laser beam width, 10° laser beam inclination angle, 10 L/min shielding gas (argon) flow with the laser beam focused on the workpiece surface (f=0). In this work selected results have been presented containing some problems and features typical for investigated joints. Butt joints produced by FSW and LBW have been compared in terms of microstructure (grains), microhardness distribution, joint efficiency, localization of failure, etc. The basic features of weld zones have been discussed together with the distributions of microhardness on the joint’s cross-sections. Both welding techniques cause a reduction of microhardness in the weld zone, but the drop from the base material’s value (135-140 HV0.1) is far higher in the case of LBW (85-90 HV0.1) than FSW (120 HV0.1). The established values of joint efficiency were 80% (376 MPa) and 66% (314 MPa) for FSW and LBW, respectively. The FSW joints tend to fail in the thermo-mechanically affected zone and LBW in the fusion zone.

This paper deals with different ways of injection molding. A plastic part can be generally filled many ways. Use of more than one gate is common in a plastic industry. Cascade molding can affect the final properties of the product, especially by the number of gates, timing of closing - opening and by the order of individual gates. A simple plastic box is used as a reference part in this paper. It is a longitudinal part with one side longer than the others. There are ribs on the bottom side of the box. The injection system is located on the bottom side of the box. The filling process is considering five individual gates. All possible filling variants are compared with respect to temperature, pressure and number of weld lines. Sequential filling from the central point of the box is the most suitable option.

Very dynamic development in the field of computerization and industry robotization, as well as an im-plementation of the Industry 4.0 assumptions are the main reason for the increased demand for magnetic materials. The limited rare earths availability and the sustainable development in the field of material engineering indicate that the methods of recycling magnetic materials from Waste of Electrical and Electronic Equipment are necessary. This paper presents the impovement stages of magnets recovery process - extrusion process of magnetic scraps/particles with polymer (magnetic scraps and particles obtained from WEEE). The process is developed based on the Process Failure Mode and Effects Analy-sis. The reserch pointed the irregularities, that pose the greatest risk of failure in the process. The paper presents changes in the process based on the values of the indicators: severity (S), probability of occur-rence (O), probability of detection (D) and the Risk Performance Number (RPN). Based on the PFMEA, 5 operations were added to the process. Due to changes in the process course, it is possible to minimize the effects of the irregularities occurrence.

The topic of the article is to compare the mechanical properties and define the differences in the degra-dation process for anticorrosive glass fibres type AR and for glass fibres type E after influence of the alkaline environment in the geopolymer composite. The ongoing reactions between glass fibres and al-kaline environment lead to the dissolution and slowly decomposition of the fibres and consequently to the loss of the mechanical properties of the composite. Corrosion of glass fibres is characterized by weight loss, change of fibre diameter, reduction of mechanical properties and formation of mineral in-crustations on the surface of the fibre, which gradually leads to the formation of a continuous corrosion coating so called corrosion shell. Scanning electron microscopy was used to monitor the morphology of the fiber surface, and image analysis methods were used to evaluate morphological changes. Tests of mechanical properties (fibers - tensile test, composite materials - three-point bending and Charpy test) were used to confirm ongoing degradation processes due to the long-term influence of the alkaline envi-ronment on both types of glass fibers.

In this work the influence of cyclic thermal tistory on the microstructure and mechanical properties of AlSi8Cu2Fe alloy was studied. The commercial aluminum alloy was subjected to a special heat treatment dur-ing which the alloy repeatedly changed from a liquid to a semi-solid state. During this process, samples were taken, and the castings were subjected to another study. Gradual changes in the microstructure, chemical com-position of the alloy, hardness and mechanical properties under pressure at normal temperatures have been documented. With the increasing number of cycles, the content of alloying elements, especially magnesium, decreased significantly, the proportion of casting defects increased, especially hydrogen bubbles, microshrinkage and oxide inclusions in the alloy. These changes also led to a decrease in the mechanical properties of the alloy. A series of samples without cyclic heat loading was also prepared for comparison.

Aluminum alloys are often contaminated with non-metallic inclusions. A large number of these phases accelerate the tendency of porosity in castings, significantly reduce corrosion resistance and above all affect mechanical properties. Melting is one of the conventional methods for removing inclusions from melt. The efficiency of this process is influenced by several parameters such as the chemical composition of the melt, the amount of refining substances (wire, salts, tablets), the melting point and the casting method. Therefore, an experiment was performed to evaluate the effect of PROBAT FLUSS MIKRO 100 on the structural integrity in AlSi10Mg alloy. Porosity evaluation was performed by light microscopy. To confirm the results and their reflexes into the practical production of castings, a static tensile test was performed on the cast samples directly in the foundry operation.

Measurement results on the Damping Loss Factor (DLF) and Coupling Loss Factor (CLF) between two steel plates is presented for 19 different junction types. The junctions involve joining technologies as line welding, point welding, bolting, riveting, gluing or their combinations, with parameters, such as spac-ing between the junction points or the angle between the plates varying. From the measurement results the DLF and CLF values were calculated by the Power Injection Method for the purposes of being ap-plied in Statistical Energy Analysis simulations. Four excitations were applied at each subsystem by impact hammer, while the response was recorded at sixteen response points at each subsystem. The measured CLF values were compared to each other from various aspects. Data were compared to the results obtained from SEA simulations by using the built-in analytical formulas. In general, good com-parison was observed, although the results appeared to be somewhat dependent on the frequency band. Finally, it was examined whether replacing the DLF values with data obtained for an uncoupled flat plate as well the CLF values with data from analytical formulas leads to acceptable accuracy of the re-sults.

This paper presents a new method of improving the material removal process in metal cutting. Chip formation plays an important factor in the metal cutting process and increasing its condition has a great impact on cutting machine details. Based on lubricating cooling conditions in the metal cutting process, a novel methodology is proposed to decrease the deformation that emerged in the material removal process while cutting cylindrical details in lathes. Application of stating magnetic field on flowing cutting fluids decreased the shrinkage of the chip in turning operation. Analytical and practical experiments show that the effect of cutting fluid under the influence of a static magnetic field decreased the shrinkage of the chip up to 20 % in comparison to the conventional use of cutting fluids in turning cylindrical pars with HSS tools.

SLS additive technology is an innovative method of metal components production, using a high material proportion. Currently, gearwheels are still one of the most used engineering parts, not only in the automotive, but also in other industries. For example, milling is used to reduce their weight, but the material can be distorted after this operation. The occurrence of cracks propagating in the transition region after induction hardening was the reason for conducting experiments with an alternative machining technology. The article deals with the identification of the influence of machining on residual stress change of a gearwheel made of sintered metal powder. The research focuses on the effect of boring on the residual stresses using a non-destructive measurement method using röntgene diffractometry.

Article presents a novel approach to addressing the challenge of forge-free filling of gas cylinder valve knobs in the context of the pneumatic shock absorber utilized within elevator systems. The shock absorber is a critical component responsible for ensuring accurate and efficient transportation of charge material to the electric inductor of automatic hot forging presses. Precise control of the shock absorber's operation is essential for maintaining proper system functionality and minimizing deficiencies. To investigate the system's response to changes in shock absorber operating parameters, the authors conducted a comprehensive simulation. The simulation results revealed that by identifying specific and optimal operational characteristics, the level of deficiencies can be significantly reduced. These findings offer valuable insights into system behavior, facilitating the optimization of shock absorber operation and overall improvement of the hot forging process. Implementation of the optimized shock absorber operation based on the simulation outcomes can enhance productivity, cost-efficiency, and quality in the hot forging industry.

The main objective of the work was to describe the laboratory methods suitable for hydrogenation of free-cutting steels and to study the hydrogen embrittlement of 11SMn30 free-cutting steel. Hydrogenation and subsequent mechanical testing of hydrogenated steel is not common laboratory method as it requires precise and expensive equipment, is time consuming and dangerous as hydrogen is highly reactive and explosive. Currently, there are several theories of hydrogen embrittlement mechanisms of steels that describe the causes of material degradation by hydrogen. However, those theories are not universally valid; individual accounts have been developed and describe hydrogen embrittlement only for specific conditions and may fail in their descriptions under others. In this work, the hydrogenation of free-cutting steel 11SMn30 steel by two different methods (immersion and ca-thodic) was investigated in order to induce embrittlement and to compare in particular the fracture surfaces after the Charpy impact test. The results reported in this paper indicate that manganese sulphide inclusions are not the main cause for hydrogen embrittlement in free-cutting steels. The effect of manganese sulphide inclusions was attributed only to hydrogen trapping, that generated a high stress causing their decohesion from the matrix.

Atomic Diffusion Additive Manufacturing (ADAM) is a recent metal sintering process based on known composite printing technology. ADAM can be classified as indirect additive production using fibre of metal powder bound in a plastic matrix. The plastic binder allows the metal powder to remain in place when is printing. Thus, a "green part" is printed and then the plastic binder is removed by the post-washing and sintering process. The aim of this work is providing a brief description of the ADAM process patented by Markforged. Furthermore, the main task was to compare the technology with other sintering technology, namely SLM technology. It works on the basis of selective bonding of metal powder using the thermal energy of the laser beam. Parameters, such as dimensional and shape accuracy, roughness of printed surfaces or tensile strength of printed samples were examined and compared. Dimensional accuracy of the ADAM process was evaluated using ISO IT grades - determined on the basis of the reference standard. The observed accuracy of the sintering process was comparable to traditional production processes.

An experimental study was carried out on the effect of oxidation temperature and the oxide film composition on the compressibility of porous materials. samples were annealed at different temperatures; the size change in the samples after annealing was measured. The phase composition of the oxide layer was investigated. Magnetite was generated at between 350 and 450°C, and two-phase oxide was formed at 550°C, after oxidation, weight gain was determined. The presence of pore overgrowth, which reduces porosity, was confirmed by metallographic tests. The maximum porosity is found in the oxidized samples produced by pressing at room temperature. The process of high-temperature oxidation of iron powder before pressing and in the state of free filling in a fluidized bed, as well as the effect of the content of oxides on magnetic characteristics, has been studied. The impact of oxidation on the compressibility of samples of iron powder was investigated. In this study, It was observed that the range of 350-450°C, which offers the best compressibility and the necessary composition of the oxide film, is also related to the presence of magnetite in the iron oxide coating. is the ideal temperature for oxidation and repressing. the deformation of porous materials exposed to iron powder oxidation was tested.

Aluminum alloys are one of the most used materials today, and therefore great emphasis is placed on their continuous development. Improving the ratio of strength and stiffness to weight, improving plasticity, casting properties or resistance to corrosion are examples of properties of aluminum alloys that are constantly being improved. This work focuses on the evaluation of the corrosion resistance of the Al-Si5Cu2Mg alloy with graded addition of zirconium (0.05; 0.10; 0.15; 0.20 wt.%). Corrosion re-sistance was evaluated based on immersion, exposure and potentiodynamic polarization tests. The addition of Zr to the AlSi5Cu2Mg alloy improved the thermodynamic stability in all evaluations. The application of heat treatment led to even more significant increases in corrosion resistance in almost all evaluations. Microscopic observation of the samples revealed mainly pitting corrosion along with intercrystalline corrosion.

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.

There is a lot of applications for manipulating industrial robots nowadays. Maximizing the tasks that can be assigned to robot manipulators is one of the criteria for deciding if their application is appropri-ate. The article discusses the topology optimization of the gripping jaws of an industrial robot to reduce the jaws' weight. The previously used gripping element made of C50E steel was optimized to reduce the weight of the jaws. Shape optimization was performed based on analysis from CAD programs Inventor Professional 2022, Autodesk Fusion 360, and Ansys Discovery. The new jaws were manufactured by the additive technology of selective laser sintering (SLS) from PA12 material. The optimization resulted in a significant reduction in weight compared to the original jaws. As a result of optimizing the weight of the designed jaws, it was possible to increase the weight of the object of manipulation.

The paper presents the possibilities of using the wavelet transform to filter the cutting force signal. Tests were carried out by dry turning on the Ti6Al4V alloy with variable cutting parameters. Four blades with different nose geometry and coatings were used. From the recorded waveforms, the mean values of the force component Fc and the load stability coefficient were calculated. The measured force waveforms were filtered with Daubechies 4 (db4) and Daubechies 6 (db6) wavelets. From the ratio of the load stabil-ity after filtration to the load stability before filtration, the noise and disturbance values generated during the turning of the tested alloy and the force measurement were estimated. The conducted research shows how the machining conditions affect the values of force, stability, and thus also the variability of the cutting edge load when turning a titanium alloy. They also show the effectiveness of the Discrete Wave-let Transform (DWT) in separating the noise from the force signal.