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The Central Solenoid Model Coil is a hybrid superconducting coil being developed in Institute of Plasma Physics Chinese Academy of Sciences. The R&D of Central Solenoid Model Coil will lay the foundation for the fabrication of China Fusion Engineering Test Reactor Central Solenoid coil. One of the main purposes during the R&D of Central Solenoid Model Coil is to verify its mechanical performance under the complicated load cases. In order to efficiently and accurately carry out the mechanical analysis, some necessary parameters such as the electromagnetic state under assembly error, the thermal contact resistance and the equivalent material property of conductor winding packet should be calculated in advance. The electromagnetic state here mainly refers to the asymmetric magnetic field and electromagnetic force. The calculation of magnetic density is based on elliptical integrals, the results will provide guidance for the assembly optimization of coil modules. And the subsequently obtained electromagnetic force will offer load boundary condition for the coil stability analysis. The thermal contact resistance is calculated under the assumption that the interface asperity approximately obeys the Gaussian distribution. The thermal contact resistance will be used in the thermal analysis. And the key advantage is which makes the prediction of preload force variation more accurate during coil the cooling down process. The equivalent material property is calculated by using generalized Hook's law and finite element method. Based on the equivalent material property, the coupling analysis model of CSMC will be significantly simplified. Moreover, it makes CSMC full model analysis under non-uniform loads become possible.

This paper deals with monitoring the influence of welding on the mechanical properties degradation in HAZ of welds at aluminium alloy AW 6005 and also with assessing the possibility of utilization the heat treatment to minimize these effects. Workpieces from alloy AW 6005 are mostly supplied in aged state. After application of the temperature cycles during welding, there is a very intensive decrease of the mechanical properties in HAZ. The mechanical properties of the weld metal, HAZ and parent material were evaluated by means of the Vickers hardness. Moreover, influence of annealing and artificial aging on the final mechanical properties of the parent material was also evaluated. Based on the results, there were chosen the relevant heat treatment parameters, which were subsequently applied in order to recover the mechanical properties of welds in the HAZ.

This work deals with an experiment, whose output is the comparison of power characteristics which were measured in three ways. The first way used a commercially manufactured dynamometer. For the second measurement, a special dynamometer with our own computing system and a sensor within this project was created. The last way of measuring the performance characteristics was done without a dynamometer. The measurement works on the principle of acceleration the spinning of a flywheel. Due to this, the measuring is called an acceleration test. The basic principles are described before the experiment in order to grasp the characteristics. All explanations are based on schemes and easy mathematical and differential formulas to describe the construction of the dynamometer and the principle of its functions from the engine to the computer. The relations between published and unpublished quantities defining engine dynamics are explained here. In the end, this work points to possible and intended measuring failures which are an infamous practice at many measuring stations.

The Ni-Ti alloys with approximately equiatomic chemical composition are one of the most important materials from the shape memory alloys. Excellent properties such as shape memory effect and superelasticity are based on the phase transformation between austenite and martensite structure of the NiTi phase. In the past the investigation of the preparation methods was focused on melting metallurgy - vacuum induction melting and arc re-melting and powder metallurgy routes like self-propagating high-temperature synthesis, hot isostatic pressing and spark plasma sintering. In the last several years importance of the additive manufacturing has increased significantly. This paper deals with formation of the Ni-Ti intermetallic phases between the nickel and titanium layers deposited on each other by direct energy deposition energy method. The varied mixture of the Ti 2Ni, NiTi and Ni3Ti phases was formed in agreement with the binary Ni-Ti phase diagram. Some problems like cracking and nickel loss have to be solved by preheating of platform or adjustment of laser parameters.

The aim of the paper is to describe the design of the manipulation system for the raw ceramic chimney pipe raw blank to avoid deformation of the pipe during handling and to increase the productivity of the manufacturing process. The process of manufacturing of a ceramic chimney pipe begins with extrusion of the raw refractory material. The extruded semi-finished product is then processed and then transferred by hand to a kiln car on which it is dried and fired. It is this manipulation that heavily contributes in the deformation of the fired chimney pipes. Due to the low stiffness of the raw ceramic chimney pipe, deformation occurs by manual handling. In order to avoid these deformations, it is necessary to design a suitable concept and construction solution of the manipulation system. Due to the nature of the chimney pipe, the automation of manipulation is rather difficult. The pipe is very soft in the raw state, its surface is rough, wet and greasy. This paper deals with the design of an optimal solution for the manipulation of ceramic chimney pipes, which will prevent the chimney pipe from deforming, negatively affecting its quality and making it possible to increase the productivity of ceramic chimney pipes production.

This paper is focused on research in the field of grinding VACO 180 tool steel. Different grinding conditions in terms of several cutting speeds and depths of cut were used for grinding tool steel with CBN grinding wheels. Two CBN grinding wheels with different grain sizes were used for several tests with the same grinding strategy. The influence of the cutting speed and depth of cut on the surface roughness was observed. The different behaviour of both grinding wheels was found during grinding in terms of achieved surface roughness. Higher grain size of the grinding wheel led to higher surface roughness, which increased with cutting speed. However, grinding with deeper cuts showed the opposite effect, and the surface roughness was better at higher cutting speeds. Lower grain size gave a more stable grinding process in terms of achieved surface roughness and lower influence of the cutting speed. However, greater wheel wear occurred during grinding with greater depth of cut. The grinding wheel was dressed before each test to ensure the same grinding ability. The results of this work will be used for a better understanding of the process of grinding tool steel.

Martensitic steels are characterized by high strength which, on the other hand, is offset by considerable brittleness. This drawback can be partly corrected by tempering, at the cost of reduced final strength. If steel is alloyed with a sufficient amount of silicon, an optimum heat treatment sequence can produce a mixed microstructure consisting of martensite and carbide-free bainite. In various microstructures of this composition with identical grain size, mechanical properties would be dictated predominantly by the fraction of bainite. This article deals with designing a heat treatment sequence for a low-alloy steel. It is part of a research into the impact of bainite fraction on mechanical properties of materials with martensitic-bainitic microstructure. At an appropriate ratio of martensite and bainite, a steel with 0.42 % C can exhibit strengths above 2200 MPa at A5mm elongation of more than 17 %.

In the urban railways environment, there is considerable stress of the track due to operation, which results in extensive deformation of the track geometric position, wear of the rail heads, expansion of the free channel of the track, leading to an increase in steering forces in the rail-wheel contact and further worsening of the situation. The authors perceive this situation primarily as a consequence of an inappropriate bogie concept of the operating vehicles - not of the track quality. The article focuses on designing a new bogie concept that takes into account the specific environmental conditions for which it is intended. The presented bogie design is characterized by the mounting of the frame on the wheelsets by means of three bearing boxes and the presence of a mechanism for adjusting the radial position of the wheelsets during ride in track arcs. This is a new, unconventional solution for which a number of patent applications have been filed. Simulation analyzes of vehicle ride with the designed bogie are currently underway. On the basis of the first results, it is foreseen that the design will increase the life of the track several times, reduce the energy consumption of vehicles and the environmental load of the environment through the transport system.

A big accent is put on environmental protection at the present time. Noise belongs in general to negative factors of our environment. For this reason, it is necessary to perform suitable measures in order to eliminate noise. For example, it is possible to apply sound absorbers in order to damp noise. Materials with porous, spongy and fibrous structure belong generally to suitable materials in terms of noise damping. The aim of the paper is to investigate sound absorption properties of different types of porous materials. Frequency dependencies of the sound absorption coefficient over a frequency range of 150-6400 Hz were determined by the transfer function method using the acoustic impedance tube. Different factors, that have influence on sound absorption of the investigated porous materials, were studied in this paper. It can be concluded that sound absorption properties of the tested porous materials are significantly influenced by material structure and thickness, excitation frequency and air gap size behind the investigated samples.

The development of economy can not be separated from sufficient energy supply. With the progress of technology, the distribution network gradually expands the capacity and transportation, but also brings security risks. The distribution automation system can effectively manage the power grid faults. This paper briefly introduced the calculation model of the economic cost and the reliability rate of the distribution automation, and then the assembly scheme of the distribution terminal was optimized by using the improved binary particle swarm optimization (PSO) algorithm. Next, the simulation analysis of the distribution terminal distribution on a 10KV main feeder line in Xuanwu District of Nanjing city was carried out in MATLAB software. The results showed that the improved binary PSO algorithm could optimize the assembly scheme of remote metering and remote signalling and the assembly scheme of remote metering, remote signalling and remote control rapidly; the hybrid assembly scheme needed a little more time; the power supply reliability rate of the optimized three terminal assembly schemes was over 99%; the hybrid assembly scheme had higher power supply reliability rate and the lowest economic cost.

Aluminium alloys are, due to their properties, an important part of all shaped castings made especially for the aerospace and automotive industry. One of the widely used alloys, for the production of castings in the automotive industry, is the AlSi7Mg0.3 alloy. In the experiment, which is the content of this paper, two castings from AlSi7Mg0.3 alloy were tested. Iron is a common contaminant in aluminium alloys and its content in the alloy is increased by the use of secondary aluminium alloys or by various causes during the production process itself. In the experiment, the corrosion resistance of castings was evaluated (in one of them the increased Fe content) under the specified conditions in the corrosion chamber with salt mist. Corrosion properties were evaluated using confocal laser microscopy. Based on the results of the microscopic analysis, the relevant conclusions were formulated. From the experiment, it is evident that the increased iron content (0.319 [wt. %]) does not, in this case, affect the corrosion resistance of casting.

This paper deals with the evaluation of the graphite cast iron structure and change of the dynamic behavior dependent on the graphite shape. Structural analysis is focused on the study of cast iron with flake and globular graphite. These two materials have a considerable application in manufacturing due to its specific mechanical and physical properties. The production of gray cast iron is less demanding in terms of the technological process and the quality of the raw materials compared to ductile cast iron but this material is the best for the production of castings. Compared with cast steels are these graphite castings less susceptible to the notch effects of fatigue stress and have a higher value of damping. Internal damping occurs in the structure of the material and can be caused by its imperfection. Computational measurement of eigenshapes and eigenfrequencies was performed using modal analysis in the SolidWorks software environment.

To achieve much higher operation parameters of EAST device, some key components are upgraded. Fast control coil as one of the key components is updated by using novel stainless steel mineral insulation conductor and the turns are increased to 4, which means the coil's operation environment becomes more severe and larger loads will be encountered. The coil joint is apt to be destroyed in view of the potential defects during the fabrication. Given the numerous advantages, the induction brazing is being considered for the conductor joint connection. The copper mock up is used to carry out the feasibility analysis. Based on the structural size of copper tube, the brazing parameters are calculated and a 2 turns splitting induction coil is designed. Some influence factors effecting the induction efficiency are analysed. It will provide guidance for choice of power supply and the optimization design of induction coil. In addition, the induction experiment is launched and comprehensive joint performance tests are subsequently performed. The test results indicate the joint overall performance could satisfy the basic engineering design requirement, but also some defects are found and more study should be carried out and to further improve the brazing quality.

Composite materials are prospective materials. An intensive research on biological reinforced composite materials has taken place in recent years. The paper deals with utilization of just this biological filler in an area of the composite materials based on a synthetic laminating resin. A microparticle and short-fibre filler based on cotton post-harvest line residues was used within the research. Many research studies devote to an evaluation of mechanical properties and an interaction of the filler and the matrix. Also a production of a final product is an integral part of the composite material development, namely in terms of a practical application. The research focused on an essential production part, namely machining by means of a water jet technology and an optimization of the cutting process based on an evaluation of a traverse speed and a cut quality. The research results proved that it was suitable to use the abrasive water jet technology for the cut uniformity (the kerf taper angle) and a deformation elimination of outlet part of the water jet from the composite material. In case of using the water jet technology without abrasive it is suitable to use lower values of the traverse speed, ca. 250 mm/min.

In urban railway environments, in many respects, the problem of tramcars passing small radius arches appears to be topical. In this regard, the authors proposed that the wheelsets should be complemented on the outer side of the wheels with a second tread of a lower radius, intended exclusively for ride in arches of the track with a radius which the conventional wheelsets cannot even theoretically pass without creep (subject of patent application a201701589). The complemented wheel tread enters into operation (or out of action) as a result of passing over a specially shaped rail located in the intersections before and behind the small radius arc. In this process, there is a change in the wheel-rail contact location - similar to what is commonly used when riding on a facing rail located in the immediate vicinity of the point frog. The paper deals with the comparison of these two cases based on a simulation analysis of vehicle ride in the calculation program.

The article deals with additive manufacturing technologies especially with ability to create reports on FDM 3D printers. These assemblies are non-disambiguable. Therefore, it is important to choose the optimal magnitude of the deviation between the walls so that the mechanism has the required mobility. These deviations are examined in several materials with different rheological properties. Finally, the dependence of the magnitude of the variance between the walls and the thickness of the layer for the given materials is shown. The result is the recommendation of modelling and printing parameters.

In the presented work, static and dynamic properties of two, theoretically identical composite rods were studied. Those two kinds of rod were made of pre-impregnated fibers so called "prepregs". The first of them was made by means of wrapping technology, which is simply just helical layering of one wide tape around a rotating mandrel. The weakness of this method is possible using only for straight parts. That is why a simultaneous deposition of several thinner filaments in a form of tape called winding was used in order to optimize this technology also for curved parts with various cross-sections.
The target of this work was to compile numerical model and experimentally compare flexural strength of the theoretically identical wrapped and wound rods in the static three point test.Further small samples cut and extracted from those rods were subjected to dynamic bending loading on Dynamic Mechanical Analyzer, with various loading speed, in order to obtain also the dynamic properties. The found results and conclusions of this article should provide a basic idea how significantly the manufacturing process could affects the microstructure and real mechanical properties of long fibers composite parts.

This article deals with the experimental grinding of cermet materials. Two types of cermet materials from different suppliers were ground under constant grinding conditions using a diamond grinding wheel. The main aim was to determine the influence of the grinding on the degradation of the grinding wheel and changes in the grinding process. Both types of cermet were ground with the same strategy and the same number of passes. The grinding wheel was analysed during grinding using an optical scanning device to observe the changes on the grinding wheel surface. Clogging and wear of the grinding wheel occurred on the surface as the amount of material removed increased. All grinding tests were carried out without dressing or truing of the grinding wheel. Degradation of the grinding wheel had a big influence on the grinding process in terms of the spindle load during grinding. The roughness of the ground surface was also measured using the optical scanning device. The results from this work will be used for further research of cermet grinding.

The presented article deals with the thermal energy influence on various types of construction steels during laser beam cutting. When the material is cut by a laser, the workpiece is subjected to intensive thermal load. Due to this influence, steels hardness is increased and the structure is changed.
The aim of this study is to verify how the thermal energy influences the surface layer of material during laser cutting. The influence was studied on data measured by DSI (depth sensing indentation) micro-hardness method. Each sample was subjected to cross-section from edge to the distance of 20 mm from the edge measurement. To evaluate surface layers during laser cutting, three types of steels with different carbon content 1.0038 (S235JR), 1.1203 (C55) a 1.7131 (16MnCr5) were chosen. The main objective was to determine the distance from the cutting point to the material when cutting with a laser beam, how its micro-mechanical properties and structure change or the distance from the cutting point to the component's hardening.

Dynamic analysis of crank mechanism is realised by relaxation method, where a connecting rod is modelled with three manners. In the first case the connecting rod is modelled as a rigid body, in the second case this one is modelled with two mass points and in the third case the connecting rod is modelled with three mass points. Results of all manners of modelling are compared and evaluated.

AISI 304 stainless steel is widely used in many industries due to its good properties such as corrosion resistance and mechanical properties. However, this steel is usually exposed to a severe environment that leads to high corrosion and mechanical failure. This study aims to examine the corrosion behavior of spin-coated AISI 304 stainless steel in a simulated marine environment contains 3.5 wt. % NaCl, by preparing and characterizing nanocomposite coatings with different weight fractions of TiO 2 (0, 1, 2, 3 wt. %) dispersed in a gelatin matrix. Three spinning speed sets (Low (L): 250-1000, Medium (M): 500-2500 and High (H): 750-4000) rpm were chosen to inspect the effect of spinning speed on the characteristics of coatings. Nanoparticles dispersed in gelatin matrix were examined by XRD, SEM, and EDX. The results approved the formation of crack-free and homogeneous coatings without any noticeable defect. Moreover, the corrosion evaluations were measured by potentiodynamic polarization technique. The results showed that compared to uncoated AISI 304 steel, the corrosion behavior of TiO 2 nanoparticles dispersed in gelatin matrix considerably improved the uniform and localized corrosion. The corrosion test results showed that increasing the spinning speed to a certain limit has a positive impact on the corrosion characteristics.

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

This paper reports on the influence of production parameters on the properties of 3D printed magnesium alloy Mg-4Y-3RE-Zr (WE43) produced by the selective laser melting method. We present microstructures and mechanical properties of four selected samples prepared under various production parameters. Optical and scanning electron microscopy together with energy-dispersive X-ray spectrometry were used for microstructure analysis. Porosity was evaluated based on image analysis. To represent differences in mechanical properties, microhardness measurement and compression tests were performed. Based on our observations of microstructure quality and performed tests, the results of the parameter impact study are further applied to the production of products of the required quality.

This study deals with distribution of carbon black fillers in rubber compounds using electrical conductivity measurements. Three rubber compounds samples were heated in resistive furnace in temperature interval 40-80°C and electrical current was measured, while voltage was constant. All samples showed a decrease in electrical conductivity with decreasing temperature, which is characteristic of semiconductors and insulators. On the other hand the large variance of activation energy can be seen for electric transport in different areas of the temperature dependence of the direct electrical conductivity. These quasi-linear areas were selected, linear regression was used and corresponding activation energy was calculated. The number of the identified areas was changing, and hence the number of conductivity mechanisms was changing as well. Clearly it can be concluded that all three samples show inhomogeneity of distribution of filler, which can be seen from the variance of values of the activation value of electric transport.

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

Polymer injection molding is the most used technology of polymer processing nowadays. It enables the manufacture of final products, which do not require any further operations. Working of shaping cavities is the major problem involving not only the cavity of the mold itself, giving the shape and dimensions of the future product, but also the flow pathway (runners) leading the polymer melt to the separate cavities. This paper shows the influence of cavity surface roughness, polymer material (with different flow properties) and technological parameters on the flow length of polymers into mold cavity. Application of the measured results may have significant influence on the production of shaping parts of the injection molds especially in changing the so far used processes and substituting them by less less expensive production processes which might increase the competitiveness of the tool producers and shorten the time between product plan and its implementation.

In this study, the three microstructure of the as-cast, hot-extruded, and 3D printed Mg-4Y-3RE-Zr (WE43) magnesium alloy was studied. The selective laser melting (SLM) process was used for 3D printing. The study was aimed at mapping the microstructure of a 3D printed magnesium alloy produced by the SLM process. Magnesium alloys made in the form of 3D printing are relatively new production processes. The study therefore this process compared with current processes, which are now well known and mapped. It was therefore studied the microstructure produced by three different processes of production. The microstructure and chemical composition of present phases were studied using scanning electron microscopy (SEM) and energy dispersive x-ray spectrometry (EDS). Based on the microstructural examination, significant differences were found between the materials produced by different production processes. The microstructure of the as-cast alloy consisted of relatively coarse α-Mg dendrites surrounded by eutectics containing intermetallic phases rich-in alloying elements. During hot extrusion, the eutectics fragmented into fine particles which arranged into rows parallel to the extrusion direction. The 3D printed alloy was characterized by significantly refined microstructure due to a high cooling rate during the SLM process. It consisted of very fine dendrites of α-Mg and interdendritic network enriched-in the alloying elements. In addition, there were also oxides covering original powder particles and the material showed also some porosity that is a common feature of 3D printed alloys.

The forging industry, and the production of high-strength forged parts in particular, saw no substantial progress in recent decades. High-strength parts continued to be made of well-tried steel grades which meet the economic and environmental production requirements, using mainly the conventional quenching and tempering. However, the latest findings in physical metallurgy of higher-silicon steels suggest that high-strength forgings can also be obtained by producing bainitic and martensitic microstructures. The first are of the CFB (carbide-free bainite) type and the latter comprise the QP (quenching-partitioning) microstructure. At greatly reduced processing costs, properties comparable to tempered martensite can thus be attained.

The setting of laser cutting technology parameters affects the resulting state of the final surface. When cutting low-carbon steel using conventional parameters - oxidative cutting, surface oxide layers are formed on the cutting edges resulting from an exothermic reaction by burning material. The oxide layers are undesirable and can cause complications if the components so produced are further coated. The color coat creates an adhesion layer on the surface oxide, and when the oxide has low adhesion to the base material, the paint drops out of the surface with the oxide. Mechanical removal of oxide by grinding, punching or brushing is another manufacturing operation that causes an increase in the cost of production. Chemical cleaning is, in turn, detrimental to workers and is also a burden on the environment. For chemical purification of oxides, phosphoric acid and the like are used. The paper describes cutting low-grade steels in a way that does not require removal of oxides and adhesion bonding between the component and the color coating is sufficient for the use of the component in operation.

Today, extensive information on a particular material can be obtained from its chemical composition using various computer programs. Such information includes phase transformation temperatures, such as Ac1 and Ac3 or the Ms and Mf, as well as the entire austenite decomposition sequence, as shown in TTT and CCT diagrams. When steel is heated, austenite grains begin to form, grow and eventually coarsen. On cooling, these grains decompose into pearlite, ferrite, cementite and hardening phases. Transformations of this kind are well understood nowadays, namely the ways the individual phases form and the rates and temperatures involved. Yet, in-situ visual recordings of such transformations are relatively rare. Using the Linkam TS1400XY heating stage, which is capable to heat samples up to 1400°C and is integrated in an optical microscope featuring objective lenses with modified working distances, these phase transformations can be observed directly. This paper explores the potential of the heating stage for studying various materials and their specific heat treatments. It also discusses the method of sample preparation for use in the heating stage placed in an optical microscope.