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The surface created by machining significantly affects the service life and functional reliability of the component. As part of this study, four different chip machining technologies were evaluated on the surface texture of the polymer material Ertacetal C. The samples were processed by turning, milling, grinding and polishing technologies, 5 samples for each technology. Within the given technology, different cutting conditions were chosen to compare the effect of cutting conditions on the resulting surface roughness. The machined surfaces were comprehensively evaluated on the basis of 16 profile and surface roughness parameters due to the practical use of the tested material. Surface texture measurements were performed on a Talysurf CCI Lite device. A non-contact method using a coher-ence correlation interferometer was used for the measurement. The obtained data were evaluated using TalyMap Platinum software. Graphical documentation of the machined surfaces was made using an Olympus DSX500 opto-digital metallographic microscope.

This article deals with the calculation of pressure vessels for beer maturation using analytical calcula-tion according to ČSN standards and with the help of commercial software PVESS. The article pre-sents commonly used procedures in the design of pressure vessels, resp. vessels for use in the brewing industry in the assembly of pressure vessels stacked on top of each other. The article describes the main parts of the brewery tanks, including the procedure for their design. The choice of materials used, the choice of basic dimensions of pressure vessels was determined in the work. The tank vessel is made of stainless steel 1.4301 or 1.4541. The advantages of this material in the brewing industry are also presented. From the given input parameters, a control calculation of the strength of pressure vessels was performed. The result of the work was the verification of the calculation, finding out the deviations of the measurements using mathematical software with a common calculation according to the valid standards for the calculation of pressure vessels.

The issue of accident analysis in relation to railway vehicles of urban mass transportation is highly accentuated at the moment. In terms of designing the frontal area of trams, adequate attention should be paid to the optimal front end design in order to reduce the risk of pedestrian injury. The properly used shape and materials can minimize the consequences of the pedestrian’s contact with the vehicle, or the eventual dragging of the pedestrian under the vehicle. For the front end to be tested and optimized, it is necessary to develop and validate a pedestrian model for performing calculations even in the design preparation stage. From a historical perspective, impact tests and pedestrian protection were not paid significant attention. There should also be a methodology for data collection and evaluation across the public transit company. The data collected within the Czech Republic is inconsistent and hard to analyze. At the beginning of our research, we addressed the question of which dummy configuration with respect to the tram is most appropriate for our crash tests.

Over the next few years, LEDs are likely to be responsible for all of the vehicle's exterior lighting func-tions. Everything is focused on maximum security. For this reason, there are more and more automatic color detection systems in the car. Proper color separation is the key to optimal operation and proper evaluation of these automatic systems. An example is the correct detection of traffic light colors. The automotive industry is dependent on consistency and predictability. Classification is an important func-tion for automated control and requires the correct color resolution of the signals captured by the camer-as. We propose to use glass containing various colored active substances such as Eu2O3, Tb2O3 and Sm2O3 as color filters for LED diodes. LED source from one visible light area to another visible light area. This study is devoted to the production of photoactive glass. Subsequently, the photosensitivity of molten photoactive glasses is tested. Both the absorption and excitation spectra of selected photosensi-tive glasses are measured.

The article is devoted to the influence of mold filling parameters by the HPDC - High Pressure Die Casting method on the mechanical and structural properties of castings intended for technology and mechanization means in forestry. Three groups of AlSi10MnMg alloy samples were formed for the experiment. Three different settings of mold cavity filling parameters were chosen. Two castings were made from each setting. Two samples were taken from two places on the casts. Thus, 12 pieces of samples were used for the experiment. An analysis of their mechanical properties was performed using a static tensile test. tensile strength, yield strength and ductility were evaluated. The microstructure was evaluated by light optical microscopy. The influence of process parameters on the quality of the casting was monitored from the point of view of the occurrence of errors, defects and the method and size of the exclusion of structural phases. The experimental results showed that the best results were obtained when the process parameters of the first group of samples were set. Their values are the closest to the customer's requirements.

The main aim of this article is study the cause of gear wheel failure. This component has worked in the motorcycle gearbox. During the operation of the transmission, the gear wheel tooth was broken, which made it impossible to continue running this device. The investigation of the damaged area was focused on determining the chemical composition of the gear wheel material as well as detecting chemical changes in microlocalities close to the defective areas. The method of energy-dispersive spectroscopy was chosen for this type of analysis. Furthermore, the micropurity and microstructure of the material were evaluated by methods of optical microscopy and scanning electron microscopy. Using a thermo-emission scanning electron microscope, the fracture surface was evaluated in the mode of secondary electrons and also in the mode of backscattered electrons. In this way, the fracture surface was examined in terms of its micromorphology as well as material contrast.

The publication focuses on the testing of the tensile strength of samples produced by Fused Filament Fabrication additive manufacturing technology. Three materials rPLA, rPETG and rPET were tested. These materials are recycled PLA (Polylactic Acid), PETG (Polyethylene Terephthalate Glucol) and PET (Polyethylene Terephthalate). These materials were used to create samples for tensile testing according to ASTM D638. In addition to testing the materials, the methodology was also tested using sets of specimens printed with no outer perimeters, one outer perimeter and two outer perimeters. Tensile diagrams were created from the measured data. Statistical processing and comparison of the measured data is performed in the publication. In the discussion, a comparison of the mechanical properties of recycled materials for 3D printing versus virgin materials for 3D printing by Fused Filament Fabrication technology is made.

This study focuses on surface treatment of aluminium alloys by High Speed Steel (HSS30) via Plas-ma Transferred Arc. The main motivation of this research has been an assignment of local company in order to prolong the lifetime of a tire press molds, especially the interface of its segments. These segmented molds are made from aluminium alloy and their interface is exposed to multiple percus-sions, which leads to cracks. Therefore, PTA surfacing is considered as a suitable surface treatment for hardening its interface, yet benefit from lightweight of aluminium matrix. For purposes of this research AlSi9CuNiMn alloy was used as a matrix metal. Permeation in the contact zone was exam-ined via confocal and scanning electron microscope. Hardness of affected matrix area was measured by using Vickers Hardness Tester.

This paper aims at the problems of poor motion continuity and abrupt acceleration of small diameter deep well rescue robot in the process of motion characteristics analysis. According to the movement characteristics and structural forms of the grasping mechanism and bracket mechanism of the deep well rescue robot, the finite element analysis of the key mechanism is carried out based on Hyperworks-Optistruct solver, according to the analysis results, the specific parameters to be optimized are obtained. And the topology optimization of the key mechanism is carried out, the optimal design scheme of clamping mechanism and bracket mechanism of deep well rescue robot are obtained. The optimization results show that on the premise of meeting the strength requirements, the grid density distribution law is obtained. According to the variation law of lightweight curve, the overall weight of grasping mechanism and bracket mechanism decreases obviously. The whole optimization process is completed and the final optimization result is obtained.

This article describes problems of porosity which are caused after welding of aluminium alloys. The main part of this article is dedicated of methods of correction of porosities. The best correction is by welding or by cementation. Described parts are used for welded aluminous vehicle parts in a cooperative company. Thanks to porosity are effected not only ductility and strength of welded structures but also weld quality thereby fall also resulting in surface treatment. Cooperative company is ranked among the world's leaders in development and production automatic, electro-pneumatic and electrically operated door systems for rail vehicles and traffic island as ramps, plateaux 'sand stairs. Staffs of this company have years' experience in the area of welding rail vehicle parts from aluminous alloys. A company has a certificate on welding rail vehicles and their compo-nents according to standards EN ISO 15085- 2. For public transport company produce sliding doors, driving and inner and among - wagon doors. The same types of doors offer for long-distance transportation and also for high-speed trains. Further, they produce traffic islands, for example, extensible ramp, extensible plat-eaux, foldaway climbs and bridging, everything is produced from aluminous alloys.

In this paper, the electric discharge perforation technology is used to preset surface texture, which effectively suppresses the generation of large cutting forces in the hard cutting process, avoids the aggravation of tool wear, and improves the service life of the tool. Use CBN tools to hard-cut GCr15 hardened steel, design three-factor non-textured orthogonal cutting simulation and experiment about cutting depth, cutting speed, and feed rate, and use range, variance and signal-to-noise ratio methods to simulate and experiment data is analyzed to determine the best combination of cutting parameters and the degree of influence of each parameter on the cutting force generated in the hard cutting process. Use the best combination of cutting parameters to hard-cut GCr15 hardened steel with a preset surface texture, observe the tool wear, measure the cutting force, compare and analyze the results under the same cutting conditions without texture to verify the preset surface texture can effectively reduce tool wear and increase tool life.

The presented article deals with the determination of selected mechanical properties of additive ma-terials used for 3D printing (PETG, PLA, ABS, ABS +, PLA ESD, ASA, PC / ABS). Due to the fact that 3D printing has exploded over recent years and additive manufacturing has become popular in some industries, the quality of input materials and their mechanical properties is extremely im-portant. We used 3D printer Original Prusa MK3 to prepare samples for testing. Individual samples printed from all above mentioned materials were analyzed using selected mechanical tests (static tensile test, hardness tests). In the static tensile test, selected parameters (tensile strength limit, ten-sile modulus, elongation) were determined for all additive samples, which were statistically pro-cessed. The parameters for two methods of measuring hardness were also statistically evaluated, namely Shore and ball indentation. All tested additive materials were compared with the aim of ob-taining the final ranking (point evaluation of tested materials with quantification of price costs). The best properties after the performed tests were achieved by the additive material PLA Filament Plasty Mladeč.

Technological progress in the 21st century has catalysed the industrial revolution (Industry 4.0) following the development of multiple new industrial automation technologies in the manufacturing sector. Regardless, past research indicated the unsuccessful attempts in adopting Industry 4.0 technologies among manufacturing organisations. Undoubtedly, the operationalisation of Industry 4.0 in manufacturing proved challenging as organisations were required to evaluate various aspects for effective implementation. Thus, a sound understanding of constructs concerning employees’ acceptance and readiness levels towards novel automation technologies was required. Hence, this study aims to explore, develop, and validate the suggested conceptual framework by integrating the Technology Acceptance Model (TAM) and Technology Readiness Index (TRI) with Exploratory Factor Analysis (EFA). The EFA process was the first crucial step in ensuring the internal consistency and stability of the instrument across the sampling population. Consequently, the research outcome potentially enabled the manufacturing sector to identify and comprehend the key determinants in designing industrial automation technologies. This study also contributed to knowledge on technology acceptance by synthesizing TAM 3 and TRI 2.0 theories, thus constructing a new TAM in manufacturing.

In the last years, the interest in micromachining has grown significantly due to the miniaturization of several components used in several fields such as automotive, aerospace and biomedical. In this scenar-io, the main protagonists are the microtechnologies and their capabilities. Micro EDM is a technology able to remove material from conductive workpieces through electrical sparks. Each spark makes a crater on the workpiece surface. Micro drilling is one of its common applications. In micro EDM drilling the geometrical characteristics of the hole are related to the electrode size. In this paper, the effects of the geometry of micro hole on the micro EDM drilling process performance have been investigated. In order to do this, experimental tests were conducted varying the electrode diameter and the aspect ratio of the hole. The influence of the electrode diameter and the aspect ratio on several indexes about process per-formance were established. This study contributes to improve the knowledge of the process and can support the users to establish the effects of the geometry of the hole on the machining performance.

This article deals with the influence of the mold material on the segregation process in selected Al-Si alloys. Three types of Al-Si alloys were chosen in order to compare the segregation process while congealing. AlSi7Mg0.3, AlSi7Cu4 and AlSi10.5Cu1.2Mn0.8Ni1.2Pb0.5 alloys were cast by gravity casting in a metal and sand molds. Macroscopic and microscopic analysis of the internal structure of each of the alloys was also studied. The chemical composition within the lower, middle and upper parts of the casts were observe by using scanning electron microscope. All samples were subjected to the Vickers microhardness measurement of a solid solution of α(Al). The distance between the secondary axes of the dendrites DAS (Dendrite Arm Spacing) was used to evaluate the level of segregation.

The laser welding method is one of the youngest but the most progressive welding methods. The advantages of laser welding include: simple automation combined with modern computer technolo-gy, very low heat input to the weld, high productivity, high welding accuracy and low noise during laser operation. In this work, the sample meltings were prepared in a protective atmosphere varying the welding parameters – laser power, welding speed, or focus position. A total of 12 samples were prepared this way. The aim was to evaluate the shape and depth of the melting of the material for selected values of parameters. Based on this metallographic evaluation, the optimal welding parame-ters were selected for a pair of austenitic stainless steel tubes (X2CrNi19-11 and X5CrNiMo17-12-2) for fiber laser welding. Macrostructure and microstructure evaluations, microhardness tests and tensile tests were performed on these welded samples.

A crane bridge is a dominant component of all bridge crane. It is imperative to pay attention on its strength features and go through a strength analysis. The introductory part of this paper points out characteristics of a bridge crane, mainly a crane bridge and materials used to produce the crane bridge, namely S235 structural steel. The paper set out the strength analysis of the main girder of a single girder bridge crane model in the means of comparing analytical and numerical solutions. The calculations take into account the load of the main beam in its centre according to the standard STN 27 0103. The bridge crane model is designed for a 500 kg load carrying capacity. The numerical solu-tions are represented by finite element method (FEM) analysis in Ansys software. The intention is to determine the deformation of the main girder depending on the weight of a load and a hoist, to de-termine the maximum deflection and resulted bending stress. Furthermore, one of the purposes is to create the precise 3D CAD model of the main girder. The 3D CAD software Catia V5 was used to design the bridge crane model. The strength analysis of the main girder of IPE 100 profile was performed by the FEM analysis using the Ansys software and by analytical calculations. The results ob-tained by the computing software Ansys were only slightly smaller in comparison with the analytical calculations. Results obtained by Ansys can be considered as more accurate. It can be concluded, such the designed and strength-checked main girder can be in the future put into a production.

Today, the emphasis is on the production of materials that are degradable in nature and on produc-tion with modern technologies. In order for these materials to find a suitable use, they need to be exposed to the conditions that may arise in the application. The effect of degradation was assessed for composite materials with a PLA matrix and a natural-based filler, which were processed by 3D printing technology. The progress of degradation in the climate chamber was monitored over a peri-od of 6 weeks. The results are determined by static tensile test and hardness test and the difference in weights of the test bodies. The test results confirmed. During the degradation process, the test spec-imens with natural fillers deformed less than the specimens made of pure PLA. The maximum ten-sile strength values for the material with natural fillers were approximately two thirds lower than for pure PLA. The maximum tensile strength during degradation showed an increasing or stagnant ten-dency. the maximum elongation decreased during degradation for the material with fillers showed a logarithmic behavior compared to pure PLA with a linear tendency.

The paper presents the results of experimental work on the assessment of 3D geometry of surface stereometry obtained as a result of Water Jet (AWJ) water-abrasive beam cutting using an Eckert Opal WaterJet COMBO hydro-abrasive cutter. Studies of geometric structures were conducted using the Alicona Infinite Focus microscope. The article analyses selected spatial roughness parameters of the multilayer structure surfaces combined as a result of the vulcanization process with an aluminium alloy surface. The results of the research work are summarized in the technological function of the WJ cutting conditions, such as the cutting speed and the mass flow of the abrasive material.

Friction stir spot welding (FSSW) is an alternative joining process mostly suitable for joining dissimilar sheets or when conventional spot welding is not applicable. In this paper, lap joint of 2 mm thickness AA1050 aluminum sheets and C10100 copper sheets using different process parameters and fixed tool geometry were investigated. Experimental plan is designed according to response surface methodology (RSM) where: tool rotation speed, plunge depth and dwell time vary between 500 and 2500 rpm, 2.1 and 3.7 mm and 0 and 8 s respectively. The main affecting and interaction process parameters are evaluated using analysis of variance (ANOVA) methodolgy. Mathematical models describing the relationship between welding parameters and shear failure load (SFL) are developed and the optimal FSSW parameters are specified. Design expert software is used for optimization of friction stir spot welding process parameters using response graphs and contour plots. With 95% confidence level, shear failure load of the dissimilar Al 1050—Cu 10100 joints are predicted using the developed empirical relations. It is found that the optimal results of the SFL is close to the optimal solution obtained from the mathematical model with less than 4% discrepancy.

In this research work, a heuristic method based on biologically motivated Particle Swarm Optimization (PSO) has been proposed for edge detection using multiresolution decomposition, to enhance the quality of the images for predicting surface roughness parameter Ra from Ti-6Al-4V turned surface images. First level Dual Tree Complex Wavelet Transform (DTCWT) is used to decompose the turned images to generate new sub band images. The performance of DTCWT with PSO method is examined for turned surface images and compared with conventional edge detectors like Canny, and Sobel methods along with Discrete Wavelet Transform (DWT) with PSO and DTCWT without edge detection. The obtained results showed that, DTCWT with PSO based edge detection provides better looking edges and also best results are obtained in terms of Root Mean Square Error (RMSE) and Peak Signal to Noise Ratio (PSNR). Further, statistical features have been extracted from the images subjected to proposed edge detection method. The extracted statistical features along with machining parameters and tool flank wear have been given as inputs to radial basis function neural network (RBFNN) to predict Ra of the turned surface images.

One of the key components in making Industry 4.0 a reality includes machines that are able to produce required products and components faster, more precisely and more flexibly than ever before based on so-called reverse engineering technology. Reverse engineering is a technology that enables rapid acquisition of data for CAD, CAM, CAE, thereby greatly shortening the development, design and fabrication of parts. In general, analogue data is converted to digital data, which is further processed. The paper deals with the analysis of prototype models of disc milling cutters with different blade profiles. The inspection of the shape of the disc-type prototypes is based on the reading of the digitized reference CAD model (workpiece with machined grooves), the subsequent positioning of the digitized protrusions of the disc mill cutters (milling cutter with edge profile 1, a milling cutter with edge profile 8) with respect to this reference CAD model, creating a colour map of the deviations at the selected points. The aim of the paper was to analyse the resulting wear (deviation of the dimensions at selected points) on the prototype of the disc milling cutters with the profiles of blades 1 and 8, which was simplified on the workpiece with the machined profiles of the grooves 1 to 4.

Aiming to study the influence of ultra-precision grinding parameters on the accuracy between the same clamping method and different workpiece sizes. This paper mainly analyzes the difference between the measurement precision of different parts by the same measurement method and the measurement precision of the same parts by different measurement methods. Therefore, the influence of grinding parameters on grinding precision is reflected. For the same part, it is concluded that the coaxiality error coincidence degree at end A and end B reaches 90.32% and 95.27%, respectively by using precision three-coordinate measuring instrument and Mahr roundness instrument. The coincidence degree of end A and end B verticality error reached 97.54% and 91.08%, respectively. For parts with different sizes, the Mahr roundness meter is used for measurement. The analysis shows that the coaxiality coincidence at end A and end B is the highest, reaching 98.36% and 92%, respectively. And from the analysis, the errors are mainly reflected in the factors such as jig and fixture and grinding process.

Deep-sea nodules are ores formed on the sea floor at depths of 3000 to 6000 m as a result of sedimen-tation. They range in size from 1 cm to 15 cm and contain mainly manganese and iron and other ele-ments that are collected from the nodules by complex pyrometallurgical and hydrometallurgical pro-cesses. These other elements of interest are bound in the nodules mainly in the form of manganese and iron oxides. In order to achieve a high yield of metals bound in nodules in the form of oxides, it is necessary to disintegrate this arrangement in the lattice. This can be achieved by exposing the deep-sea nodules to a reducing condition. This paper deals with the one-step recovery of metals of interest from nodules using silicothermic reduction with 10% excess silicon over stoichiometry. The phase composition, microstructure and mechanical properties of the obtained reduced material were determined.

The article presents new possibilities of simulation software and its application to improve the pro-duction structure. In many enterprises, the basic issues are related to the determination of planned tasks for individual positions, calculating the demand for employees, taking into account their skills and qualifications, calculating work costs, determining work efficiency and its dynamics. Therefore proper work organization consists in setting the course of work in such a way as to obtain maximum results with the least amount of work by man and machine. The article presents the problem of per-sonnel allocation to the production line. The basic stages of developing a simulation model of this process are discussed, including all necessary information and inputs. The results shows impact of the selected simulation scenarios to the workload level of the staff and the duration of the production process. In this concept, to solve the problem a simulation model of the production process was built. A new generation of 3D FlexSim simulation environment with an integrated OptQuest optimi-zation module was used.

When measuring roundness, accurately adjusting the measured part is very important. The axis of the measured part must be perpendicular to the section where the roundness is measured. If this fails, a systematic error will occur. It depends on the size of the inclination of the surface during the meas-urement. The paper presents mathematical relations to calculate the error when measuring roundness on a cylindrical and conical surface. It analyses the influence of the inclination and the parameters of the measured area on this error. The theoretically determined values are compared with the practical-ly measured roundness values. The error harms the accuracy of the roundness measurement. It af-fects the value of roundness, but also the roundness profile itself. It is explained that the mistake can not only increase but also decrease the measured value of roundness, in conclusion.

Production of primary aluminium is energetically enormously expensive. The use of secondary (recycled) aluminium, has therefore a high potential to save money and energy while reducing the negative environmental impact of aluminium production. Although the properties of secondary aluminium alloys are generally comparable to those of primary aluminium alloys, the increased Fe content can lead to a significant reduction in the corrosion resistance of these alloys. Secondary (recycled) AlSi7Mg0.3 cast alloy with different iron contents (0.123, 0.454, 0.679 and 1.209 wt. %) in the as-cast and after heat treatment (T6) condition was investigated. The quantitative analysis was focused on the evaluation of the Fe-phases, especially the needle-like Al5FeSi phase. The corrosion resistance was measured by a rapid corrosion test (AUDI test). The corrosion damage of the surface was observed macroscopically. The results show that Fe content higher than 0.454 % has no significant effect on the amount and size of needle-like phases of Al5FeSi. The corrosion resistance is mainly influenced by the size and length of the Al5FeSi phases. Increased Fe content decreases the corrosion resistance of AlSi7Mg0.3 alloy and accelerates the initiation of corrosion.

The Edge Localized Mode coil is the key component to prohibit the phenomena of disruptive instability occur-ring in the edge of Tokamak plasma. And the coil is made of Stainless Steel Jacketed Mineral Insulated Con-ductors. The different pieces of conductor are connected by joints. During the normal operation of Tokamak device, the joint will be shocked by electromagnetic and thermal loads. Thus, it is necessary to perform the mechanical analysis to verify whether or not the ELM joint has sufficient safety margin to resist the impact of coupling field. In order to obtain the load boundary condition for mechanical analysis, the electromagnetic and thermal analysis are launched first. Then the temperature and electromagnetic force density are inserted into the mechanical analysis model. And the equivalent stress is calculated. The analysis results indicate there is stress intensity at the component of supporting rail. To mitigate the stress intensity, the local structural optimi-zation design is employed. Finally, the stress evaluation is carried out based on analytical design. The assess-ment results demonstrate the optimized model has sufficient safety margin to withstand the combined action of multiple loads.

The application of different structural materials to manufacture basic parts of drying units of various types was analyzed. It has been established that surface erosion of materials resulting from solid par-ticles' impact is a serious problem for many industrial equipment types using multiphase flow. It is shown that the value of the erosion rate depends on the local particle impact velocity and the impact angle and can be calculated using the software Ansys Fluent 18. The basic principles and criteria for selecting materials for the manufacture of chemical equipment were substantiated. The behavior of steel and polymer material for shelf contact of the convective dryer in the conditions of erosion wear was modeled, the comparative characteristic was made, further research was planned.

Providing products with higher quality and lower prices is considered to be a competitive advantage for the industrial firms over competitors. This main challenge can be achieved by minimizing the overall production costs and operational time. Lean manufacturing provides many tools and techniques to iden-tify and eliminate wastes and to reduce costs in production systems. In this paper, single minute ex-change of die (SMED) technique is used as a lean manufacturing approach in a leading Palestinian aluminum profiles company. SMED was implemented through real experimental procedures applied to the extrusion line processes to investigate its effect on decreasing the setups time and improving the Overall Equipment Effectiveness (OEE) of the extrusion machine, in addition to introduce a guide for practitioners to improve the extrusion process dies exchange in similar industries. Overall, the successful implementation of SMED resulted in an increase of OEE by 3.26% as the consequence of the increase of machine availability by 4.86%.