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The boride coatings are characterized by attractive set of properties such as high hardness and wear resistance, corrosion resistance in higher temperatures and no wettability by liquid metals like alumi-num and zinc. This type of coating might be used for manufacturing of different parts from tool steels. In present article the influence of pack boriding time (2,4,6h) on microstructure and phase composition of obtained coatings is scrutinized. The pack boriding process was conducted on two groups of cold work tool steels: low-Cr content: 145Cr6, 90MnCrV8, 60WCrV8 and high-Cr content: X165CrV12, X153CrMoV12. The commercial boriding pack Ekabor 2 was utilized and the process was carried out using industrial CVD device (Bernex BPX Pro 325S). The conducted research showed that the boride coatings formed on the substrate of high-chromium steels were characterized by a lower total thick-ness. On low-chromium steels, FeB phase was discontinuous as an irregular islands located in the near-surface area. On the other hand, for high-chromium steels, a continuous layer of needle-like borides was formed.

Conventional spinning is one of the oldest processes used widely in manufacturing to obtain cup shape products. Conventional spinning is the technique that produce axisymmetric part or component over rotating mandrel with the help of rigid tool known as rollers. The shape of roller is very important parameter for the success of the spinning process. This paper datils about using ball shaped rollers as forming tool in conventional spinning process experimentally. The experimental work was carried out on the center lathe machine as forming machine, the spinning tool or spinning rollers was installed on a dynamometer replaced the tool post while the mandrel was mounted on the lathe chuck. The spinning tool in this work consists of three rollers performing the conventional spinning. The set of rollers is mounted on jaws of lathe chuck which working as a holder for the spinning tool parts. The experimental work was conducted in order to test the proposed tool and investigate the influence of the main conventional spinning parameters (mandrel rotational speed, axial feed and blank diameter or spinning ratio) on the process forming load and the product quality. The response of the product quality and required load to process parameters such as rotational speed (76,150, 230 and 305 rpm), axial feed (0.08, 0.15,0.3, and 0.6 mm/rev) also examined new rollers in different mandrel diameters 45, 60 and 80 mm. The experimental results showed that, the suggested tool acquired a spinning ratio of 2.17 which is about 35% greater than the announced conventional spinning ratio of 1.6 without any addition to the tool just using the suggested Ball shaped roller arrangement. the mandrel rotational speed, and axial feed rate are the most pronounced parameters, which have great effects on the forming loads during the spinning process.

In warehousing logistics, the sorting and transportation efficiency of goods is still one of the important factors limiting the rapid development of logistics. At present, most regions still use manual sorting with low efficiency and high cost. Especially in some special work areas, such as high temperatures, severe electronic radiation, and areas with heavy long-term work tasks, urgent need for small robots to replace manual labor. In order to solve the inconvenience that small places such as logistics only use manual sorting, It is necessary to design a small-sized weight sorting and transportation robot, which can wait for receiving goods at a designated location, judge and identify the weight of goods by itself through PID intelligent control algorithm, which can move forward at a constant speed, and transport its weight to the designated position and unload it. Constant speed can make the trolley travel more smoothly and load and unload goods more smoothly, which is of great significance.

Additive Manufacturing has enabled the design of complex components in several technical fields. Considering turbomachinery components, additive manufacturing has unlocked the achievement of significant performances for dynamic rotoring components. The application of topology optimization methods is one of the main factors accelerating the technological development of this sector. This paper presents a procedure for the optimization of static turbomachinery components. The frame-work proposed compares the results obtained by introducing a lattice structure and a solid optimized shape. The procedure is presented with reference to a specific case study. To validate the proposed framework, the complete re-design of a thrust collar of a major Italian-based Oil&Gas company is carried out, demonstrating that the re-thinking of the component in terms of Topology Optimization is a straightforward approach to increase the overall performance of the produced part.

This article summarizes the results from the fire resistance test of geopolymer suspensions in the form of coatings on non-metallic substrates. Their heat resistance was evaluated based on the burn-through time compared to the uncoated substrate. Non-metallic substrate materials, extruded polystyrene (XPS) and chipboard (DTD) were chosen as the underlying substrates for GP suspension research. Parameters from the fire resistance test as fire test duration of geopolymer coatings and percentage increase in burn time of geopolymer coatings on an XPS and DTD substrates compared to an uncoated substrate were evaluated. One of the discussed point was also the addition of CaCO3 and Al(OH)3 for studding flame retardancy effect.

Nickel superalloys are the main materials used in manufacturing of turbine blades and vanes in aero-space industry. They works is extremely high temperature in a corrosive environment (oxidation, hot corrosion) and undergo several different thermo-mechanical loads. Aluminide coatings are the main method of protection of the surface of nickel superalloys against exhaust gasses environment in jet en-gine. In presented article the microstructural characterization of aluminide coatings produced using two industrial methods (pack cementation and out of pack was conducted. The commercially available powders manufactured by Oerlikon-Metco were used in aluminizing process using industrial Bernex BPX Pro 325S CVD system. The MAR M247 was used as a base material. Amount of activator and pure aluminum had a noticeable effect on the total thickness of obtained layers. Both samples with increased activator and pure aluminum content formed 5 to 11.5 x thicker aluminide coatings in comparison to other sample, which was aluminized using an Al-Co powder as aluminum source. Further investiga-tions are needed to specify precise phase composition of analyzed coatings.

Austenitic steels are among the most widely used materials in industries such as automotive, food, energy, chemical, etc. They are mainly used due to properties such as corrosion resistance, good strength, hardness, or weldability. Microstructural analysis was performed on a light microscope Neo-phot 32. AISI 304 austenitic steel has a microstructure formed by a large number of polyhedral austenite grains of different sizes. The steel microstructure, mechanical and fatigue properties, and areas of the plastic zone after the bending impact test were investigated. The surface hardness of samples was measured on a Zwick Roell ZHVμ microhardness measuring device using the Vickers method. After the bending impact test, fractures were formed with a significant deformation with a typical dimple morphology. The fatigue test, performed on a Zwick Roell resonant pulsator, monitored the plastic deformation causing changes in mechanical properties. Finally, fractographic evaluations of the fracture surfaces were performed on a Tescan Vega LMUII. scanning electron microscope.

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

The article is focused on the effect of mixing the additional material with the substrate (base materi-al) on the properties of the weld metal during arc welding with TIG technology. The research is aimed at the use of arc welding with TIG technology in the repair of foundry molds. These are repairs of permanent steel foundry molds. The parts of the mold in contact with the liquid metal are subject-ed to heat-chemical-mechanical stress. This load causes mold wear, which causes a decrease in sur-face quality and a change in the dimensional accuracy of the casting. The main cause of wear on the functional surfaces of the mold cavity is tribological processes. From the study of professional works dealing with mold wear [5,11,22], it is clear that one of the main parameters for determining the in-tensity of wear is surface hardness. The theoretical part deals with wear and the factors that affect wear. The experimental part compares the properties of one, two, and three-layer TIG welds, specifi-cally the chemical composition, hardness, and coefficient of friction determined by the "ball-on-flat" method.

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.