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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.

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 use of most commercial magnesium alloys is limited to working at normal temperatures. The excellent ratio between the mechanical properties and the density of magnesium alloys necessarily leads to the development of new types of alloys that would be usable even at elevated temperatures. This would significantly increase the applicability of these alloys where steels or aluminum alloys are still used, especially in the transport industry. The problem with today's high temperature resistant magnesium alloys is the need to use expensive rare earth alloys. Significantly cheaper alloys of magnesium with zirconium and calcium are studied in this work. The microstructure, mechanical properties under pressure at the temperatures of 20, 150, 200 and 250 ° C were studied for several alloys with different contents of Zr and Ca. Furthermore, the stability of alloys during their long-term temperature exposure was studied. A very positive effect of the studied additives on the properties of alloys was found, which gives these alloys a very promising perspective in the future.

In the present study, an innovative method is proposed to improve the accuracy of thermal models of the grinding process. To this end, a set of orthogonal experiments are carried out to calculate heat flux using infrared temperature measurements. Then the convective heat transfer coefficient is modified based on the heat transfer and hydrodynamics theories. Finally, the modified heat flux and convective heat transfer coefficient are applied and a thermal model is established using ANSYS software. To verify the accuracy of the proposed model, a finite element grinding residual stress model based on the grinding heat and grinding force is established. By measuring the grinding residual stress and comparing it with the finite element residual stress model, the effectiveness of the grinding thermal model is indirectly verified. The obtained results demonstrate that the modified grinding thermal models are accurate and can be applied in engineering applications.

The main aim of this case study is to present the changes caused by heat treatment on the structure and properties of 100Cr6 steel by annealing, hardening, and tempering in combination with previous chemical-heat treatment (CHT) by boriding. The boriding causes changes to the microstructure of the steel samples, which include a change in the morphology of the deposited cementite and a change in the volume of the chromium carbide particles. The cementite is transformed from its original granular form to a lamellar form. An increase in the proportion of chromium carbide particles in the sample occurs due to the higher affinity of chromium for carbon. This leads to precipitation of chromium carbides rather than carbides of iron. A multi-phase diffusion layer Fe2B-FeB with a thickness of 31 ± 2.8 µm is formed during boriding, with a typical tooth-like texture. Although the diffusion layer does not have the same toughness and resistance as the single-phase Fe2B diffusion layer, samples after boriding increase their resistance to tribological abrasion by 29 % compared to samples without this treatment. After quenching and tempering of the borided samples, a maximum tensile strength of Rm = 1779 MPa is measured. Compared to samples which are only quenched and subsequently tempered, this is an increase in tensile strength of about 59 %.

Polyvinyl butyral is a material that is widely used in the manufacture of laminated glass sheets. Polyvinyl butyral film is widely used as an intermediate layer for laminated automotive or architectural glass. The intermediate layer primarily ensures the safety function of the laminated glass. Other advantages of laminated glass with a polyvinyl butyral interlayer include that it can be adapted to perform other functions, including acoustic functions, anti-reflection functions or functions enabling information to be projected on the glass with this interlayer. In this work, the influence of further processing of polyvinyl butyral film with non-uniform thickness is studied. Further processing may have a negative impact to the profile of PVB material.

In this paper, the adhesive behaviour of different polyurethane glues was studied and compared. The study was inspired by real conditions in the production of car windows, and it is divided into several parts, which deal with three types of polyurethane adhesives. The first type is a standard one-component polyurethane adhesive, which cures with air humidity. The second type is a one-component polyurethane adhesive with the addition of a curing accelerator. And the third type is a two-component polyurethane adhesive. Adhesive blocks of defined dimensions and plastic parts glued to the glass were used for this experiment to simulate a real product. The influence of temperature and humidity on the curing process was evaluated. The test included measuring the force required to tear the parts from the glass and assessing the type of failure. Based on the achieved results, the adhesives were evaluated regarding their applicability in the real automotive industry and the key properties necessary to maintain the safety and quality of the glued part were determined

High-entropy alloys are known to possed good mechanical properties which are usually related to the preparation technique. In this work, the CoCrFeNiMnXAl20-X (X=5, 10, 15) alloys were prepared by a combination of mechanical alloying (MA) and com-pacted via spark plasma sintering (SPS). Such prepared materials were examined for their phase composition and microstructure. Furthermore, their mechanical properties as a result of the content of Mn/Al were determined. It was found, that the partial substitution of Mn by Al lead to increasing the volume content of the solid solution with BCC crystallographic lattice within the ultrafine-grained microstructure of such prepared materials. Moreover, increasing the Al content within the alloy lead also to the improvement of the mechanical properties. The CoCrFeNiMn5Al15 alloy reached the best properties of all the alloys showing compressive strength of 2496 MPa and having a hardness of 668 HV 1.

The article presents results of the use ABC method applied to technological machines modernity level assessment in anti-corrosion protection of steel structures. Research findings enables identifying and analysis of the technological modernity level of machines used in the anti-corrosion protection process that is crucial for the final quality of the process and product manufactured in the steel construction production. The paper proves effectiveness of using ABC method of the machines modernity level as-sessment in the analysis and improvement of the steel construction corrosion ensuring process.

In the whole world, the economic loss caused by hull corrosion is enormous. Ship painting has become an important part of ship manufacturing process because it can effectively alleviate the corrosion of ship. The manual painting has disadvantages both in the quality and the efficiency. However, the research of automatic sprayers for a ship hull is not widely used because of the complex environment in the shipyard dock and the huge differences in both size and shape of ships to be repaired. Therefore, this paper pro-posed a new method: according to the ship size and blocks distribution in the blocks’ layout of ship yards, the grid method was used to generate the map model; to solve the problems of high rerouting rate, low coverage and large consumption of calculation in the global path planning, a regional division method was proposed to divide the whole area; to shorten the dock occupancy time, a path planning algorithm based on multi robots heuristic cooperation was proposed. Simulation results and experi-mental data show that the full coverage path planning algorithm proposed in this paper has satisfactory adaptability.

The article presents the results of the use Six Sigma DMAIC cycle to improve workplace safety and decrease the cost associated with work accidents in the company from the automotive branch. Selected tools of the DMAIC cycle were used at each stage: the project card and the Pareto-Lorenz diagram at the define (D) stage, the matrix diagram at the measure (M) stage, the Ishikawa diagram with the verification of causes at the analysis (A) stage, the 5WHY method at the improve (I) stage and the c control chart at the control (C) stage. Each of the successive stages was based on the results of the previous one in order to achieve a lasting solution for the analysed problem by the implementation of remedial measures. Because of the implementation of remedial measures, the level of work safety in the examined company was improved. The DMAIC analysis made it possible to identify the main causes (Xn) of accidents at work and to objectively evaluate them in order to discover the root cause (Xn!) of the problem. The root cause turned out to be inadequate protection of the lathe due to the protective cover installed too far away from the lathe chuck, which resulted in the catching of protective sleeves or gloves of the lathe operators and accident events in the form of upper limb damage. The solution to this problem was to reduce the gap between the guard and the lathe chuck by adjusting the guard so that no more items of workers' clothing were caught while the machine was running. The article proves the effectiveness of using the Six Sigma DMAIC cycle in analyzing and improving the state of occupational safety and is an incentive to use this cycle and a specific set of tools to analyze similar problems.

This paper focuses on the issues of tool thermal deformation during machine preheating，designing an image-processing-based solution for measuring these tool thermal deformation, to obtain the axial thermal error of the tool as a function of preheating time.This paper uses a high-speed camera to collect images of tool thermal deformation. Using MATLAB software, rough localization of images by Canny algorithm for edge extraction. Accurately locating tool edge outlines using a sub-pixel fitted edge detection method, that is, using the least squares method to fit a tool tip arc curve. From this, the thermal deformation during tool preheating is calculated. This study will serve as a basis for the compensation of thermal errors in machine tools.

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.

After the Fukushima accident in 2011 year, ATF nuclear fuel cladding concept was accelerated to achieve the reactor operation with the new accident tolerant structural materials. However, several designed solutions do not fulfil the accident tolerant concept but particularly increase the corrosion resistance of Zr-cladding tubes at normal operating conditions, so-called “Advaced Technology Fuel, EATF”. Cr-coated zirconium claddings following the first concept, have been the widely tested and the first full Cr-coated fuel rods have been planned to operate in LWR reactor conditions around the 2022 year. Our contribution describes the Cr-coated Zr-%1Nb cladding tube microstructure after high-temperature steam oxidation at 1200°C by means of Scanning Electron Microscopy and nanoindenta-tion methods. The article is focused on WDS line-profile studies of oxygen and chromium diffusion into the Zr-matrix. The increased Cr-diffusion with oxygen is evident causing a change in local me-chanical properties which is well-described by measurements of nanohardness and Young's modulus. In addition, the developed methodology of the WDS & nanoindentation line-analyses was also opti-mized to apply in hot-cell conditions to measure the effect of neutron-irradiation on the different coat-ings and coating/matrix interface.

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 given paper deals with the issue of materials used in the treatment of heart attacks. In more de-tail it focuses on individual types of stents and their specific properties. The article describes selected groups of biocompatible metal-based materials. Our attention is mainly paid to magnesium alloys. The introduction explains the concept of biocompa-tibility and the distribution of materials accord-ing to their biological tolerance. In the experiment, we performed an ana-lysis of the chemical com-position of individual metal stents and focused on examining their wear resistance. Since it is too difficult to imitate human body environment, we opted for corrosion test for the experiment. Stents were exposed to the given concentration of the solution and temperature. The time period during which the stents were in solution was also important. In the final part, we focused on the microscopic evaluation of the surface.

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.

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.

The development of metal structural materials with low density, high specific strength and large internal friction is extremely urgent for the development of lightweight, high speed and high power of equipment and railway. The properties, microstructure and the evolution of interfacial bonding of composite materials are closely related. In this paper, the microstructure of Ti2AlC/Mg matrix composites with double-scale three-dimensional network is mainly studied. The prepared composite material presents a three-dimensional network in macro-micro scale, and the matrix and reinforcement are connected with each other. The mechanical properties and damping properties of the prepared dual-scale three-dimensional network Ti2AlC/Mg matrix composites and magnesium alloy matrix were tested. At the same time, the equivalent modulus of three-dimensional network Ti2AlC/Mg matrix composites on microscopic scale is predicted by finite element method according to the basic properties of Ti2AlC ceramics and AZ91D. The following conclusions are drawn: the ultimate bending strength of the composite material is increased by about 10% compared with its matrix magnesium alloy, and its ability to maintain strength is greatly improved compared with the matrix. Using the extracted information, the equivalent modulus of the composite microscopic model is calculated to be 31.25734 GPa, which is consistent with the experimental results. It provides data and theoretical support for similar research.

Stress corrosion cracking (SCC) is a common cause of structural failure. The simultaneous action of the corrosive environment and tensile stresses creates cracks that have an intercrystalline or transcrys-talline character. These are cracks with a fragile morphology of the fracture surface without signs of plastic deformation in their vicinity. SCC cracks occur in several alloys. This paper focuses on copper alloys in which this type of failure occurs frequently. Examples from practice show cases where the occurrence of SCC violation was related to the conditions of use of components and their production technologies. The paper does not aim to capture all the influences associated with the occurrence of SCC failure of copper alloy products.

Precipitation hardening is one of the most frequently used methods of the post-processing heat treatments of 3D printed tool steel 1.2709, as it increases the yield and ultimate tensile strengths of the steel. Within this work, the broad temperature range of 250°C – 550°C was tested with five differ-ent holds at each temperature to study the effect of processing parameters on the microstructure and mechanical properties. Maraging tool steel 1.2709 was produced by selective laser melting (SLM) technology and obtained results were compared with conventionally produced steel of the same chemical composition. Mechanical properties were established by hardness measurement and tensile test and the microstructure was characterised mainly by light and scanning electron microscopy. The peak hardening was for both steels reached after 6 hours of precipitation at 500 °C, however, apparent hardening effects of heat treatment were observed already after low-temperature heat treatments.

Mechanical alloying and subsequent compaction with spark plasma sintering was chosen for the fabrication of investigated CoCrFeNiTi alloy method. The alloy was characterized in terms of chemical and phase composition with X-ray fluorescence spectroscopy and X-ray diffraction spectrometry, respectively. The microstructure was examined using light microscopy and scanning electron microscopy equipped with an energy dispersion spectrometer. The alloy showed an ultra-fine grained uniform microstructure composed mainly of an FCC solid solution with a volume fraction of HCP Laves phases. Regarding mechanical properties, the prepared specimen reached an ultimate compressive strength of 1340 MPa with the hardness of 757 HV 30. The wear rate of the sample reached 1.19 · 10-4 mm3·N-1·m-1 showing traces of adhesive-abrasion wear mechanism.

The article deals with a possibilities of an enhancement of functional properties of highly stressed components by specific combination of surface technology. Two surface technologies such as plasma nitriding and laser shock peening were selected for the experiment. Those technologies were applied upon steel 42CrMo4 frequently utilized in manufacturing of strained components. Properties obtained by applied surface technologies were tested by following experimental methods. The chemical composition was verified by optical emission spectrometer Tasman Q4 Bruker. The surface morphology was inspected by scanning electron microscope TESCAN MIRA 4. The microstructure of heat treated as well as of nitrided specimens was observed by opto-digital microscope Olympus DSX500i. The microhardness profiles were measured by microhardness tester LM247 AT LECO. The friction coefficient was tested on tribometer Bruker UMT 3 TriboLab. For an assessment of the surface wear resistance the profilometer Talysurf CLI 1000 and Contour GT were utilized. The experimental results show that although the proposed surface technology combination manifests itself to be disadvantageous, both technology LSP, as well as plasma nitriding, applied separately, can lead to a significant wear reduction.

The quenching and partitioning (Q&P) process is an advanced method of heat treatment of high-strength steels. The resulting properties of Q&P-processed steels are dictated by their microstructure which consists of tempered martensite, fresh martensite and retained austenite (RA). These phases arise from individual steps of the Q&P-process. An important step is stabilization of retained austen-ite because RA raises ductility to above the levels found in conventional steels upon quenching and tempering. If the desired stability of RA is to be achieved, Q&P processing must not initiate compet-ing processes associated with carbide precipitation or austenite decomposition into bainite-like mi-crostructure. Yet, it appears that the very decomposition of austenite into bainite is an accompanying process that takes place at the partitioning stage, the stage which plays an important role in terms of mechanical properties of Q&P-processed steels.

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.

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 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.

There are regional differences, variety differences and maturity differences in fresh lotus seeds. The parameters of husking and peeling machine working parts need to be adjusted in real time according to the processing effect. In response to the problems with the machine on the market including complicated transmission, difficult interconnectedness and adjustment of various working parts, etc., an automatic husking and peeling machine for fresh lotus seeds with the husking module and peeling module as the core devices has been designed. On the basis of the kinematic analysis of fresh lotus seed circulation process, a grooved wheel feeding mechanism and an arc track have been designed to realize the feeding and circulation of fresh lotus seeds. Experimental research has been conducted on the influence of working parameters on the film removal effect and the interaction between working parameters using the response surface method. In addition, the correctness of the above analysis has been verified by husking and peeling experiments. According to the experiment results, processing qualification rate and damage rate processing efficiency of this machine can meet the use requirements of lotus farmers. This research can provide a theoretical basis for the structural design and parameter optimization of related equipment.

Reduced deep-sea nodules were tested as the alloying mixture for cast and rapidly solidified aluminium alloy. No separation of any metal was used in order to save the processing costs of the deep-sea nodules and to obtain “natural” ratios between the alloying elements. The resulting rapidly solidified alloys contained sharp-edged intermetallics, especially Al9Mn3Si phase, which was converted to rounded Al19Mn4 during thermal exposure. The hardness of the ribbons was almost stable during long-term annealing at 300 and 400 °C for 250 h. The alloy can be considered as highly thermally stable.

The conventional solid-state friction welding process involves imparting a movement to one of them, bringing them closer together so that there is friction from the clamping force. By overcoming the frictional resistance on the surface of the workpieces, work converted into heat is generated. The obtained heat heats the elements to a temperature close to the melting point but not exceeding it. After stopping the movement in relation to each other, the process of pressing the elements with the force P with a greater force causes plasticization of the material and the formation of a flash. In low pressure friction welding, most of the heat required for the joining process comes from the induction coil. This means that two key process parameters such as friction time and contact force are significantly reduce. This affects the course of the process and the end result of the process of joining materials. The shape and size of the flash as well as the size of the heat-affected zone in the weld will change. Among the many advantages of this method of joining metals, one should mention the possibility of welding smaller parts, thin-walled, with complicated geometry, which the friction butt welding process would not be able to cope with. Additionally, there is a possibility of heat treatment. In order to verify the feasibility of the friction welding process with low pressure in industrial conditions, a number of tests presented in this study were carried out, together with the analysis of the results. A number of proposals for the optimization of low-force friction welding with the use of artificial intelligence have also been developed has also been developed. A simpler but less effective solution is application of neural networks. It is possible due to multiple digital recording and process automation parameters with digital recording and process automation This solution approach is not as productive as the proposed hybrid algorithm combining neural networks, fuzzy logic and genetic algorithmsThe hybrid method enables you to take advantages of all three algorithms in the position optimization.