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Various structure states before quenching significantly influence final mechanical properties as well as the dispersion of chemical composition at the same steel grade. Therefore heat treatment with mechanical properties is specified in the technical delivery conditions. Even if the heat treatment is determined, different mechanical properties can be achieved. These differences are increasing in im-portance in high-strength applications like springs, cutting tools, safety, and load-bearing parts of automotive design et al. Because it has a direct impact on their lifetime. The structure consists of ferrite and cementite after spheroidization annealing prior quenching process. The cementite could be observed in various shapes, e.g. fine and large globular particles or the rest of the disintegrated lamellar shape. This article shows how these cementite morphologies affect the quenching behavior and final mechanical properties in high-strength spring steel 54SiCr6.

The presented study focuses on measuring volume changes in elastomeric materials using digital image correlation (DIC), specifically the 2D DIC universal system and the 2D DIC video-extensometer directly implemented to the universal testing machine. Optical measurement methods were applied in two-dimensional (2D) configurations during the mechanical testing of dumbbell-shaped test specimens under uniaxial tension. The measured data were used to determine the dependencies of the bulk modulus and Poisson's ratio on the strain. The dependencies obtained by both methods correspond to the model behavior of rubber-like materials. Compared to the 2D DIC implemented video-extensometer, the 2D DIC universal system provides a tool for measuring transverse and longitudinal strain, and a wide range of post-processing options, including change of the input parameters, settings, or calculation relations.

In the actual factory production, there are often cases of liquid flow accumulation, and most of the controllers used in the project are PLC. Usually, the flow meter is used to measure the instantaneous flow, and then the analog (4-20mA) signal is transmitted to the PLC, and the PLC accumulates the cumulative flow within a certain period of time according to the instantaneous flow transmitted by the flow meter. Due to the floating point type of PLC, the direct accumulation will not reach the accuracy standard, and the cumulative error will occur. In order to eliminate the cumulative error, this paper proposes an improved algorithm based on Kahan 's algorithm. The improved algorithm greatly reduces the error of the cumulative flow than the original Kahan algorithm. The reduction of error is of great significance to the data analysis and production calculation of liquid or solid flow in the field of process industry control.

In order to accumulate experience in the design and manufacturing of the toroidal field coils for the China Fusion Engineering Test Reactor, a model coil of mixed Nb3Sn-NbTi superconducting magnet with a maximum magnetic field variation rate of 1.5 T/s has been developed at the Institute of Plasma Physics, Chinese Academy of Sciences. The preload system, as one of the key components of the model coil, plays a crucial role in maintaining the overall integrity and stability of the model coil. First the magnetic field and electromagnetic forces of the model coil under extreme conditions are calculated based on Maxwell's equations. Then, the mechanical performance of the model coil at room and cryogenic temperatures is analyzed. To addressing the issue of excessive stress in the preload components of the model coil under preload, several optimization design schemes are proposed and iteratively analyzed. Finally, stress linearization is performed, and stress evaluation is conducted based on the analytical design. The assessment results indicate that certain optimization schemes enable the preload components to fully meet the operational requirements at both room and cryogenic temperatures. The outcomes presented in the paper will provide reference for the subsequent design and manufacturing of the central solenoid coil.

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.

The article deals with the quality of the driving characteristics of a passenger car with passive shock absorbers depending on the tire pressure. The work was solved using experimental methods using the AHS test bench. The main goal of the work was to assess the vehicle suspension system using acceleration sensors and pressures between the wheel and the road using shock absorber test benches using the EUSAMA and CAP methodology. The results of the work demonstrated the possibilities of using the measurement of acceleration values in selected places in the vehicle. The obtained results were also verified for the possibilities of further development in the area of reducing the dynamic load when driving a passenger car on the road.

Laser cladding technology is used to clad the surface layer of H13 mold steel with Ni60A metal powder coating to solve the failure problem. The study used JMatPro software to extract and fit the thermophysical property parameters of the substrate and the clad material, and then used ANSYS APDL software to qualitatively analyze the distribution of melt pool morphology, nodal temperature versus time course curve and residual stress magnitude during the laser cladding process. Based on the results of the minimum residual stress in the cladding, reasonable scan paths were derived for the preparation of metal coatings on the surface layer of the die steel. The results show that the maximum peak temperature of the cladding process is 2515°C using short path scanning. The cladding layer can form a good metallurgical bond with the substrate at this temperature, with a stress of 406.68 MPa in the scanning direction and 284.45 MPa perpendicular to the scanning direction, which is significantly smaller than the residual stresses of other scanning methods. The residual stress values for the different strategies are from largest to smallest: spiral scan > block scan > long path scan > short path scan.

A model-based viewpoint planning and filtering method is proposed to determine the position and pose of viewpoints in 3D reconstruction of multi-view images. The method first determines the necessary parameters to control the camera position and attitude. Second, the mathematical error model is developed and combined with stereo overlap to guide viewpoint selection. According to the shooting distance, a dense candidate view area is then established, the subview collection is screened, & a view supplement scheme is proposed for the area where the candidate view cannot be shot, improving the integrity of the resulting data. Experimental results demonstrate that our viewpoint planning method has high shooting coverage & highly accurate 3D reconstruction.

This paper analyses surface after laser beam machining with respect of surface height irregularities, residual stress state as well as microstructure on the low alloyed steel S 235. Surface after laser beam machining is investigated due to its specific nature resulting into coating delamination. This coating delamination can be found especially in the regions in which component shape or/and curvature of the profile is altered. Especially the components corners suffer from the delamination due to exten-sive surface heating and presence of brittle oxides layer. The thickness of this oxides layer is hetero-geneous with respect of the component thickness as well as the component geometry. It was found the oxides layer is the thermally initiated process since in these regions the underlying matrix also exhibits the higher thickness of the heat affected zone and higher degree of the hardening expressed in term of HV0.1. Furthermore, also the compressive residual stresses exhibit higher amplitudes in the region remarkably affected by the thermal cycle.

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.

In this paper, the design of a robot is proposed to replace manual labor in completing tasks on vertical planes. The aim is to enhance automation in the workplace and eliminate direct human involvement to ensure personal safety. Firstly, the robot's structure is designed as a five-joint biped with vacuum adsorption capabilities. The forward and inverse kinematics of the robot are analyzed. Secondly, using simulation by ADAMS, five key performance metrics are quantitatively analyzed for both this robot and a Hexapod robot. These metrics include adsorption reliability, external load-bearing capacity, friction coefficient adaptability, obstacle-crossing capacity, and joint torque. Thirdly, the main control chip used for this robot is STM32F407. The circuit system design and physical implementation of the robot are based on this chip. Finally, experiments are conducted to study the actual performance of the robot in vertical cleaning tasks.

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.

The work deals with the possibility of using additive technology in the production of positioning and clamping device. The designed clamping device will facilitate and accelerate the measurement of samples with inclined or different irregular surfaces. The designed device is manufactured by additive technology using composites. Onyx material reinforced with Kevlar fibers was used as material for composite printing. The designed device should achieve the required properties for the firm and stable clamping of the components during the measurement process, and its weight should be significantly reduced with the use of composite material.

The quality properties of high pressure die casts are closely correlated with porosity. The formation of porosity is primarily initiated by entrapment of air and gases in the volume of the melt, during its transition through the gating system. This entrapment can occur as a result of an incorrect design of the gating system, incorrect setting of the casting technological parameters, or sometimes a combi-nation of both causes. The setting of the piston velocity in the first and second phase of the casting cycle has the highest proportion of the gas entrapment of all the technological parameters. The sub-mitted article is describing the influence of piston velocity in the first phase of the casting cycle. Ve-locities are investigated in range from 0.1 m.s-1 to 1.3 m.s-1. First of all, the development of the wave arising at different piston velocities is assessed and the gas entrapment in the melt volume is investi-gated. Subsequently, the proportion of the gas entrapment in the cast volume at the end of the filling phase is investigated depending on the variable value of the piston velocity in the first phase. In the end, the determination of the piston velocity impact in the first phase on the completion nature of the filling chamber of the machine is derived.

According to the application requirements of SOC in lithium batteries of Unmanned Aerial Vehicle (UAV), an Extended Kalman filter-Double Kalman filter (EKF-DKF) composite model was proposed to optimize the accuracy of the last 20% stage of State of Charge(SOC) estimation. Based on the equivalent model of second-order resistance-capacitance (RC) circuit improvement, the developed method optimized the identification accuracy of parameters, and set up a MATLAB simulation platform to jointly estimate SOC online with EKF and DKF. The data obtained in laboratory test environment were used for simulation.

With regard to the current economic situation, which deals primarily with energy prices, companies are trying to find reserves within individual technologies. The automotive industry is still a very important industry. One of the ways to improve the material properties of a body part is thermomechanical processing. This is how the B-pillar, which serves as a safety structural element of the car, was processed. The presented article aims to investigate the influence of selected thermomechanical processing parameters on the resulting properties of a B-pillar made of high-strength steel 22MnB5. At the same time, energy saving in the given production process should be used in such a way that it is not at the expense of the quality of the component. Three kinds of experimental production processes with different parameters of thermomechanical processing of steel were proposed for scientific investigation. Based on these proposed processes, several pieces of B-pillars were produced and subjected to further investigation. Changes in material properties were monitored using hardness measurements and subsequently the resulting microstructure of the material was examined for each experimental post.

This paper provides an overview of the commonly used processes and equipment for laser cladding, including pre-set powder feeding, simultaneous powder feeding, wire feeding cladding, and coaxial cladding nozzles. By comparing the above processes and related nozzles, the coating characteristics are summarized for the selection of appropriate methods and equipment in different working environments. Meanwhile, the morphology and properties of the clad layers of shaft parts processed with different process parameters (e.g. laser power, scanning speed, lap rate, powder feed rate) and the influence of the combined parameters are overviewed. The changes and mechanisms of metals, ceramics, and metal-ceramic composites in terms of hardness, wear resistance, metallurgical bonding, and microstructure are analyzed. In addition, the application of numerical simulation techniques to simulate the temperature and stress fields and to plan the melting trajectory when laser cladding processing is performed on the surface of shaft parts are reviewed. Finally, the problems in the current research on laser cladding of shaft parts are summarized and the development directions are discussed.

A modern user requires low operating costs, but also reliability from machines and technical devices. Reliability during the service life depends on the quality of construction solutions, but also largely on the quality, properties and adaptation to the working conditions used in the construction of construction materials. During the operation of technical objects, their a highly predictable wear occurs. The problem is the phenomena of premature wear and damage of elements. The causes of failure of technical facilities are usually complex and depend on many factors. They can include the human factor and the one related to the quality, selection, production and technological processes of the materials used in the construc-tion of the facility. In real technical facilities, many premature failures are caused by material fatigue, which is related to the quality and distribution of impurities in the material. The paper presents the change in fatigue strength for rotational bending of low-carbon structural steel hardened and tempered at different temperatures as the effect of the size and distance between impurities on the fatigue strength of high-quality carbon structural steel melted in the industrial conditions in an electric arc furnace.

In recent years, 3D printed arm casts can replace traditional arm casts to treat bones fractures. 3D printed arm cast modelling often uses professional 3D scanning systems to capture 3D data of the arm. These systems are very expensive and may not be available in many hospitals. In order to over-come this disadvantage, inexpensive methods should be developed. This paper introduces a new data collection method based on smartphones. The photos of an arm were taken with a smartphone cam-era using some special techniques that could facilitate the process of image processing and 3D mod-elling in Agisoft Metashape and CATIA. To validate the proposed method, the photogrammetric model was compared with the scanned model (obtained by a low cost scanner) in GOM Inspect. Be-sides, a fit check of real 3D printed arm casts attached on the volunteer's forearm was also per-formed. The test results indicate that the photogrammetric model could be used as raw data for 3D arm modelling.

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.

In order to cultivate students' professional skills and enhance students' practical ability, this paper proposes to create a virtual simulation experiment system of NC machine tool based on SolidWorks software platform, taking vertical machining center as the research object, which is integrated by three modules of NC machine tool structure, machine tool operation and machine tool processing. Firstly, the detailed assembly relationship of each subsystem of the machine tool, the assembly rela-tionship of the overall equipment and the system composition are displayed intuitively by 3D modeling, so that students can understand the 3D modeling method and structure composition of complex CNC machine tools. Secondly, according to the machining process characteristics of vertical machining center, using typical parts to create the virtual simulation platform to carry out complex parts programming and machining methods and steps based on vertical machining center. Through the full combination of virtual simulation experiment and actual equipment, it has significant results in improving students' interest in learning, ensuring teaching effect, reducing material waste, avoiding machine tool accidents and so on. And combined with the actual processing, operation of CNC machine tool experiment to achieve the combination of virtual and real, vivid image, rigorous and realistic, open and sharing, expand the numerical control technology class teaching and talent training. It also provides a good reference for similar curriculum development.

Machining is an important part of the manufacturing process in the engineering field. Turning is one of these areas. At present, almost exclusively exchangeable cutting inserts are used in production machining. The article describes the research in the field of their wear, where the electron microscopy was used to evaluate the results. Electron microscopy is a very important aid in research in many are-as not only of human activity and also is the important aid in the field of mechanical engineering and manufacturing technologies. The results thus obtained can make in a given area it clearer and better document the resulting situation. Within the experiments, selected cutting inserts were used and the given material was machined. The electron microscope Tescan Vega 3, which is available at the workplace where the experiment was conducted, was used to evaluate the resulting wear. In the frame of experiments was also performed the composition analyze of used cutting inserts. Analyzes of the machined material were also performed to confirm the declarations from the supplier.

This article deals with the comparison of the wear of indexable CNMG carbide inserts from two dif-ferent manufacturers when turning austenitic stainless steel 1.4404, which is not intended as the pri-mary material to be machined from the point of view of the tested inserts. The main goal was to demonstrate the different course of wear by testing inserts of the same type according to ISO 6987 showing the connection between the design and processing of the inserts in connection with the se-lected cutting parameters. The monitored type of wear was the main flank wear VBmax, depending on the length of the machining time. Optical and electron microscopes were used to analyze the flank wear. According to the assumption, it was found that the layout of the cutting edge geometry and coating layers has a noticeable effect on the degree of wear of the evaluated cutting inserts. At the same time, it was found that the tested indexable inserts achieved very good service life values de-spite the fact that the tested material does not belong to the primary use group. Evaluation of cutting tool wear has a significant economic potential for manufacturing companies seeking to minimize costs by trying to use as many universal cutting tools as possible or looking for opportunities to ex-pand the applications of already used cutting tools.

This article deals with adhesion of various alkali-activated metakaolin-based geopolymer coatings on structural steel 1.0038 (according to EN 10025-2). This steel alloy was chosen in order to analysis ad-hesion of prepared geopolymer coatings. Our samples were characterized by laser and SEM micros-copy and grid test was performed. Microscopy was performed to get knowledge about visible charac-terization and overall quality of prepared coatings. Based on previous research SEM results corre-spond with properties changes in coatings and their classification of grid test. Grid test was per-formed and results was evaluated. These results show potential of our prepared GP and could be used as base for further research and possible application as anti corrosion coatings in construction or fire-resistant barriers. The aim of the research was to prepare alkali-activated metakaolin-based geopoly-mer on a structural steel substrate, to evaluate the visual quality of the coatings and to evaluate the results of the grid test.

Nowadays, a lot of data is generated in production and also in the domain of assembly, from which different patterns can be extracted using machine learning methods with the support of data mining. With the help of the revealed patterns, the assembly operations and processes can be further opti-mized, thus the profit achieved can be increased. This article attempts to explore the patterns related to the most used Key Performance Indicator (KPI) in manufacturing, the Overall Equipment Effec-tiveness (OEE) metric. The patterns and relationships discovered will be sorted into Assembly Pattern Catalogue (APC). Firstly, a literature review demonstrates scientific relevance. Secondly, it examines the circumstances and methods of samples in the Manufacturing Execution System (MES) data source and Enterprise Resource Planning (ERP) systems. In the third section, the detailed pattern catalogue is defined in the area of assembly. The novelty of the article is that beyond the generaliza-tion of patterns, it characterizes the pattern catalogue with mentioning practical industrial examples.

The 54SiCr6 high-strength low-alloyed steel with medium carbon content is studied in this work. Its excellent mechanical properties allow a wide range of applications as springs and vibration dampers. The high strength is usually achieved during heat treatment consisting of quenching and tempering. This manuscript represents several methods to further increase in mechanical properties. Firstly, the influence of microstructure before quenching and tempering was studied and enhanced plastic prop-erties were measured. Secondly, a thermomechanical treatment before quenching increased the strength. Finally, the use of strain assisted tempering caused a further strengthening effect compared to conventional tempering. All these methods improve mechanical properties, some increase strength and others ductility.

In today's manufacturing industry, composites are widely used. This is primarily due to the highly variable material properties that can be obtained by combining various materials as reinforcements and matrices. However, modern environmental concerns have pushed researchers and engineers to seek materials from organic and renewable sources. The study will look into composite surface roughness during the cutting process, which will involve milling with a CNC router machine. A portable surface roughness tester will be used to obtain a surface roughness average (Ra) reading, and microscopes will be used to examine the composite surface roughness behaviour under a microscope. Based on the results of the experiment, 82 wt.% vinyl ester resin on coconut fibre composite provides the best material properties. With a constant feed rate of 500 mm/min applied to spindle speeds of 5,000, 20,000, and 30,000 rpm, the 5,000 rpm showed the best surface roughness average performance compared to the other two. Further research focusing on feed rates may be required to better deduce the material machining data.

This article deals with the influence of plasma nitriding and sensitization on the microstructure and microhardness of AISI 304 austenitic steel. The microstructure of AISI 304 austenitic steel in all states was observed on a Neophot 32 optical microscope. The initial structure consisted of polyhedral austenite grains of different sizes. The microstructure contained a large number of non-metallic MnS-based inclu-sions. After plasma nitriding, a continuous nitriding layer was formed under the steel surface, while the grain shape was preserved. After the processes of sensitization and plasma nitriding followed by sensiti-zation, carbides were excluded along the austenitic grain boundaries were excluded. The nitriding layer began to deteriorate due to temperature and length of sensitization. Vickers microhardness measure-ment on a Zwick/Roell ZHμ machine proved that the nitriding layer is reaching the high hardnesses compared to the core of samples. After sensitization, the nitrided samples achieved only slightly in-creased microhardness compared to the core. Finally, EDX analysis of the nitriding layer was performed on the SEM and compared with the layer that was affected by the sensitization process.

PM2.5 and PM10 measurement technique based on light scattering usually exhibit inaccurate measurement results in their applications. For improving the reliability of this method for PM2.5 and PM10 measurement, systematic research on the structure optimization of single particle light scattering sensors (SPLSS), calibration of SPLSS, and PM2.5/PM10 monitor development are carried out. Frist, by simulating and optimizing light scattering parameters, light scattering signals varied monotonically with particle size could be obtained, and thereby capability of accurate size-identifying can be established. Then, by developing threshold comparison circuit and calibration device, particle size channel of SPLSS or monitor could be divided, and particle counting efficiency could be corrected. Finally, by obtaining empirical values of parameters, i.e., heating temperature, particle density, involved in the developed dynamic heating system and PN-PM algorithm, interference of humidity and particle characteristics can be effectively eliminated, thus particle mass concentration (PM) could be calculated according to particle number concentration (PN) in each channel. The results show that the developed monitor has good accuracy by comparing it in atmospheric air with reference methods of PM2.5/PM10.

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.