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The paper deals with a method and technology for increasing of precision sorting of transparent materials - glass. The recycled glass is a valuable material which is necessary as an ingredient in the process of glass manufacturing. We propose a very fast industrial device based on FPGA (field-programmable gate array) image processing along with a novel algorithm for a robust real-time treatment of acquired data. The system consists from a line-scan camera with fast CameraLink interface, FPGA processing, battery of valves propelled via pneumatics and nozzle block. Very important part of the system is a background configuration software enables precise assessment of required limits as inputs to FPGA processing. The overall performance is discussed from the perspective of laboratory and industrial tests. The proposed FPGA image processing can be utilized for further future enhancements in the field of precise sorting of glass with stuck labels on it. The results give very good performance even in the industrial environment with a lot of dust and dirt and hence the glass does not need to be extensively cleaned.

Additive manufacturing (AM) has shown promise to process parts for end-use applications, however stringent requirements must be fulfilled in terms of reliability and predictability. The expensiveness of raw materials for AM, especially for metal-based Powder Bed Fusion (PBF), brings about the need for a careful recycling of powder, but the effect of powder reuse on both processing conditions and final part performance is still the focus of intensive research in the open literature. Although ASTM F2924-14 specifies the virgin-to-used powder ratio to be introduced to manufacture titanium-6aluminum-4vanadium (Ti-6Al-4V) components by PBF, a deeper understanding of the effect of powder recycling on the mechanical properties of finished parts is expected to foster a more efficient and safe reuse. The present contribution is therefore addressed to investigate the consequence of Ti-6Al-4V powder recycling on the flowability, particle size distribution and morphology of the feedstock material as well as on the density and tensile performance of built parts. In order to quantify the recyclability of powders, a new "average usage time" (AUT) parameter is defined to account for both the real usage time of the powder and the virgin-to-used powder mixing ratio. The new parameter, whose applicability can be readily extended to any kind of feedstock powder, offers a significant contribution to achieve a more consistent and economical recycling of raw materials for PBF processing.

This paper deals with the research of common and the proposed wedge type shock absorbers for bogie used by 12-7019 KRVZ open box type cargo wagon. Results of elements stress-deformation state caused by static load analysis performed by computer simulation are presented. Diagram of elements displacements, spring group compression dependence on vertical load, equivalent stresses of suspension system elements, proportional load distribution diagram and diagram of energy absorption by friction damper were obtained. The influence of spring group construction to the cargo wagon dynamics when running at speeds up 10 to 200 km/h was investigated. Advisability of the proposed wedge type shock absorbers construction improvements was confirmed.

The experiment described in this article deals with the possibility of AlSi12 alloy alfinal bath mechanical properties change used in the manufacture of the compression ignition engines pistons by the addition of manganese. The alfinal bath is intended for the aluminium layer deposition which provides more convenient connection of the carrier with the aluminum alloy after casting in the mold. The analysis performed in the experiment were focused on the assessment of the manganese addition influence in the form of the AlMn20 master alloy on the resulting mechanical properties of the AlSi12 alloy in which the iron content gradually changes (up to 7 wt. %). The iron is released from inserting cast iron rings. The research is primarily focused on assessing of strength and hardness of the alloy which is affected by the occurrence of intermetallic phases excluded in the microstructure depending on the ratio of iron to manganese content. The alloy with the high Fe content was subjected to the static tensile test and Brinell hardnes test measurement after the manganese addition.

The article deals with the determining of the characteristic signal of the inductive FT3 measuring probe, that is used on the roundness machines of Jenoptik IM producer. The research was the basis for generalized recommendations for the calibration of the probe, which was published in the article "A roundness machine measuring probe calibration". The signals of eight FT3 probes have been acquired and evaluated for repeatability and mutual equality. Five signals of each individual probe were taken immediately for repeatability evaluation. The deviations of the individual signals from the mean signal and the deviations of the signal first derivative curves from the mean first derivative curve have been evaluated for the repeatability evaluation. The deviations of the signal of the individual probes from the perfect signal have been evaluated for the equality evaluation.

This paper deals with different ways of injection molding. A plastic part can be generally filled many ways. Use of more than one gate is common in a plastic industry. Cascade molding can affect the final properties of the product, especially by the number of gates, timing of closing - opening and by the order of individual gates. A simple plastic box is used as a reference part in this paper. It is a longitudinal part with one side longer than the others. There are ribs on the bottom side of the box. The injection system is located on the bottom side of the box. The filling process is considering five individual gates. All possible filling variants are compared with respect to temperature, pressure and number of weld lines. Sequential filling from the central point of the box is the most suitable option.

The given paper is closely connected with the numerical modal analysis of eigenfrequencies and eigenshapes for turbine blades of the turbojet engine with the help of the mathematic modelling. The mathematic model was created in Pro-Engineer program and it was subsequently created to the ANSYS program in order to apply finite element method. Distribution of the stress in the turbine blades is presented in [Pa]. The presented results of the eigenshapes and distribution of the stress are obtained in the graphic form.

In the case of eutectic and hypoeutectic silumins, the modification is carried out on molten metal prior to casting with strontium, which has a limited modification effect of max. 1 - 1.5 hours. The aim of the realized experiment is to investigate the microstructure change and corrosion evaluation of the AlSi7Mg0.3 aluminium alloy in combination with the strontium modifier. AlSi7Mg0.3 alloy was used for the experiment using 0.04% strontium modifier and 0.15% beryllium was added to prolong the time effect of the strontium modification. Beryllium was used as an AlBe5 master alloy and the samples were cast by gravity casting into a metal preheated mold. Chemical composition analysis was performed by spectral analysis and microstructure was evaluated by light microscopy. Alloys formed without and after the addition of the modifier were subjected to a corrosion test followed by evaluation of the initial microstructure.

The effect of Zr was assessed on changes in the mechanical properties of the alloy under investigation by the addition of Zr with a graduated increase by 0.05 wt. % Zr. Experimental samples were cast into ceramic molds, half of which were hardened by precipitation after casting. The measured values indicate an improvement in the mechanical properties, especially in experimental alloys containing Zr ≥ 0.20 wt. %. In the evaluation of Rm, the most significant improvement occurred in the experimental alloy with the addition of Zr 0.25 wt. % after heat treatment and E in the experimental alloy with the addition of Zr 0.20 wt. % after heat treatment, as well. The effect of Zr in the AlSi9Cu1Mg alloy investigated was also analyzed for porosity. It can be concluded that the addition of Zr into alloys is manifested by an increase in gassing of experimental alloys, especially in variants containing Zr ≥ 0.15 wt. %. At a higher Zr content there was a significant increase in the DI density index and pore size. For higher amounts of Zr ≥ 0.20 wt. %, long acicular phases with slightly cleaved morphology are visible in the metal matrix. Exclusion of the Zr phase nuclei with regard (also) to the change of exclusion temperature can cause capture of hydrogen bubbles (pockets) and thus increase the gassing rate.

Fe-Al-Si alloys based on Fe-Al, Fe-Si and ternary Fe-Al-Si phases have been recently proved as the materials highly resistant to high-temperature oxidation. However, high brittleness limits their application as bulk materials. Therefore this work aims to test them as the protective coatings for the carbon steel and to test the high-temperature oxidation resistance of the coated samples. The coatings by FeAl32, FeAl35Si5 and FeAl20Si20 alloys were produced uncoventionally by the combination of mechanical alloying and spark plasma sintering. It has been shown that the best resistance against the oxidation in the air at 800 °C was reached in the case of the FeAl35Si5 coating. Fe - Al binary alloy coating oxidized more rapidly, while the FeAl20Si20 coating tended to delaminate.

This study is focused on the effect of pigments on polycarbonate (PC), especially the dimensional stability and flow properties of this material. This polymer is commonly used in the plastics industry and the most common processing of this polymer is injection molding technology. Three different pigments made by Lifocolor company were selected for PC staining. In addition, six different concentrations of aforementioned pigments were used. It is worthwhile to note that the pigments in the polymer matrix acted as a filler. Just like fillers, the pigments also influence the shrinkage of the polymer in both the main and secondary directions. The paper also deals with the effect of pigment concentration on the melt index (MFI). It was shown that the presence of pigments reduces the thermal mobility of the macromolecular chain. Melt flow index changes were also directly tied to the changes of the viscosity, which was also affected by the pigments. It can be expected that the viscosity might not remain the same even at varying shear rates.

A Matlab-based calculation method which can be used to partition a free-form surface into regions is presented in this paper. Based on surface curvatures and Freeman chain code technique, a free-form surface can be devided into convex, concave and saddle regions. A Matlab program containing some M-function and script files was developed to create the mathematical model of the free-form surface, calculate the surface properties, and find the points on the boundaries of the regions. Two surfaces were given as examples to show that the program runs well and output of the program was used to create the CAD (Computer Aided Design) model of the partitioned surface in Creo Parametric.

Aiming to reveal the friction and wear performance of slipper pair, a high-precision slipper pair friction and wear testing machine must be used. Aiming at the material of the main shaft of the transmission system of MCMS-10 slipper pair friction and wear tester, a research on the main shaft material of the transmission system of the tester by CFRP (Carbon Fiber Reinforced Polymer) is presented. Mainly for the theoretical analysis of the mechanical properties of CFRP, establish a mathematical model, and use the ANSYS Workbench module to the transmission system modal and static analysis. Simultaneously, CFRP is applied to the test machine spindle whether it meets the test machine transmission system requirements, and the stratification of the spindle is compared and analyzed. The results show that the application of CFRP to the main shaft of MCMS-10 tester not only meets the requirement of experimental performance, but also improves its transmission performance on the basis of the original. The maximum displacement and the maximum stress of CFRP are reduced by 0.003513 mm and 13.576 MPa respectively.

This paper deals with 3D printing of metal parts. There are many principles of 3D printing, for example, DMLS, SLS, CLADDING, etc. This paper is limited to 3D printing using DMLS (Direct Metal Laser Sintering). 3D printing using DMLS can create complex geometries that cannot be created using other metal manufacturing processes. This principle is based on sintering of metal powder in thin layers. Thin layers of powder are applied by a recoater blade. The shape of the part is sintered with a precise and high-wattage laser in this layer. The part is built layer by layer. The printer used for the experimental part of this paper was an EOS M290. The material of the recoater blade was ceramic and the powder material was MS1. There are several types of recoater blade but this article focuses on the limitations of using a ceramic blade recoater. The influence of the orientation and size of support structures depending on the recoater blade was examined. Also, the effect of the height of the support structures on their vibrations was investigated and the vibration of the support structures was described in detail. The influences and limitations of the recoater blade were investigated.

Main aim of this paper is to analyze the thermal behavior of different cooling channels and to describe advantages of manufacturing of a mold with these channels using a 3D printer instead of drilling machines. This work was primarily done by the usage of virtual simulation. Validation of thermal simulations was performed by usage of simple analytical solution. A simple model of molded brick was designed to analyze the cooling time and the temperature distribution in the mold when changing the cross section of the cooling channels. Three types of different rectangular cross-sections and one circular were chosen. All of them have the same area. The cooling channel with circular cross section was positioned closer to the part in next design and influence of this change was analyzed. Last tested configuration is conformal cooling channel with a channel path twice longer. It is obvious, that most suitable configuration of cooling channels is combination of conformal design with rectangular shape as close as possible to plastic part.

Irradiation of polymeric materials is a modern method of modifying their final properties (for example, improvements in mechanical, thermal and chemical properties). The main used types of radiation to modify polymers include ionic and ionizing radiation. Due to its properties, ionization beta (electron) radiation is the most widely used. The interaction of ionizing radiation with polymeric materials manifests as radiation cross-linking, which is a result of recombination of migrating polymer radicals into the amorphous region. In this type of radiation, electrons are generated under high vacuum using a hot cathode. Electrons emitted from the cathode are then accelerated in the electrostatic field that arises between the cathode and the anode. The depth of penetration into the material rises with increasing energy of electrons. This study examines the influence of ionizing beta radiation on the flammability index and ignition temperature of thermoplastic materials.

The paper describes the utilisation of several physical diagrams for the modelling of chosen electric car charging in alternative simulation software for an electric power system. The description and evaluation of possible ways for modelling of electric vehicle charging with the results that are sutable for basic energetic analysis are performed, and for all cases given models are used in chosen simulation circuits. Modelling of electric vehicle charging becomes important with the increasing trend of used electric cars and installed charging stations. Electric vehicle charging represents the rising amount of loads with nonstandard behaviour which has been connected to the distribution power grid. The behaviour of electric cars during charging is not the same as a standard passive load, which can be defined by consumed active power for a specified period of time. The charging process has a specific behaviour, which is derived by the type of a charging station and communication with the battery in the car. While charging the distribution grid is influenced. The undesirable occurred phenomena are unbalanced powers and generation of harmonics, which can cause voltage and current asymmetry in the grid and subsequently worsen electrical voltage quality. Furthermore, the load capacity of distribution lines is reduced and therefore the steep increase of loading limits their safety and economic usage.

The paper presents the results of the surface morphology of aluminium alloys after milling. The 3D surface roughness parameters Ra, Rz, RSm were examined. Functional relationships between the cutting forces, the torque and the roughness parameters were established. The investigation was carried out with respect to functional characteristics of the surface of aluminium alloys. Two different aluminium alloys: 2024 and 6082, were investigated. Two different milling strategies were employed: milling with a trochoidal tool path and milling with a conventional tool path. Different radial depths of cut were applied in the tests. The percentage of the radial depth of cut was increased every 5 %, from 5 % to 40 %. The results were compared with the conventional machining.

Machining, mainly turning, si characterised by the highest labour input among the technological methods. This leads to the conditin when, for instance, in line production at hammering power press, which produces forginngs in the stroke of 1 second, tens of lathes follow and their gradual turning with the stroke of tens of seconds up to minutes. Whole history of material machining has been lead with the effort to shorten machining time by the improvement of cutting materials, tool geometry, integration of machining The article based on the method integrates roughing and finishing into one operation and ensures high quality of machined workpiece surface.

Nowadays there is a high trend and effort to find a suitable biodegradable metal, whose mechanical properties would be the same or higher to those of currently used biomaterials. Current biomaterials, such as stainless steels, cobalt-chromium alloys, and titanium alloys have superior mechanical properties, machinability, and durability, but are considered nondegradable, and long-term clinical complications may occur. Their biggest disadvantage is that the patient must have undergone a second removal surgery. Therefore, new biodegradable materials have been developed to eliminate the shortcomings of current biomaterials. Magnesium (Mg), iron (Fe) and zinc (Zn) based alloys have been proposed as biodegradable metals for medical application. Iron-based alloys show good mechanical properties compared to magnesium-based alloys. However, both of them exhibit bad corrosion properties, because the degradation rate of magnesium has proven to be high. On the other hand, the degradation of iron-based alloys is too slow in a physiological environment. The corrosion attack of both materials is not typically uniform. Therefore, zinc is proven to be a promising material for this application.

This article deals with the influence of grinding conditions and tilting the spindle on changes in the spindle load when grinding tool steel on a 5-axis tool grinding machine. The experiment was designed to investigate any changes in cutting speed, feed rate or tilting of the spindle. The size of the load is very important, because the load can influence the tool life, the life of the machine components, quality of the surfaces and dimensional accuracy of the components. A medical femoral knee replacement was selected as the semi-finished component for the experiment, as its surface is a good representative of a complex-shaped surface. This article is limited only to the grinding of maraging steel MS1 with a CBN grinding wheel. The second part of this article is focused on the experiment where the spindle load is evaluated and the results of the experiments are compared.

Thanks to their chemical and physical properties, the cutting fluids can significantly affect the process of machining - the use of cutting fluid reduces the roughness of the machined surface and increases the tool life. However, during the machining the oil from the hydraulic system of the machine often gets into the cutting fluid, which can alter the properties of the cutting fluid. In scientific literature there is no information on the effect of the hydraulic oil entering the cutting fluid on the tool life and roughness in machining of the structural steel. In this regard, at the laboratory of the Department of Machining and Assembly of the Technical University of Liberec, there has been conducted a study to ascertain the effects of hydraulic oil getting into different types of cutting fluids during the milling of structural steel.

Lightweight constructions are in demand for applications which require low weight accompanied by rigidity. From this perspective, lattice structures are an interesting design solution in conjunction with additive manufacturing technology. This study addresses promising lattice topologies. A range of metallic lattice structures was produced using Direct Metal Laser Sintering technology and the samples were exposed to uniaxial tensile load. During the tensile tests crack initiations and locations of the breaks were observed. The results clarify the weaknesses of the cellular lattices and reveal their maximum tensile load. First steps have been taken to meet the demand for optimized lightweight AM products.

The operators' poor adaptability on photos and difficulties of removing background point and noise point and other problems make the conventional focusing synthesis techniques difficult to get better application and promotion in the field of three-dimensional reconstruction. In this paper, a modified Laplacian operator was used as an evaluation basis to select focus points and the theory of three-dimensional reconstruction was discussed from the perspectives of image multilayer composite algorithm and height interpolation. To solve the problem of removing noise point and background point, a double threshold selection technique was proposed, which greatly improved the adaptability of focusing evaluation operator. Finally, a test on three-dimensional reconstruction of the tool wear's surface topography was conducted.

The aim of the research on the newly developed eutectic silumin type AlSi9NiCuMg0.5, developed and patented by a team of staff of the Faculty of Mechanical Engineering, was to determine the cause of the cracking of castings under operating conditions. When the technology was put into practice, the casting was cast and then used to break the entire casting section and create a crack that crosses the whole cross section. Castings were cast by low-pressure die casting technology, where the mold is fed into the mold cavity via a cast iron tube. The essence of the research was to perform a fractographic analysis of the fracture area, to identify the structure of the casting, to identify the structural components on the surface of the fracture surface by EDS analysis on an electron scanning microscope and to determine the chemical composition of the material in the area of refraction compared to the declared alloy. From these results we can clearly identify the cause of premature cracking of castings from the newly developed eutectic silumin. Additionally, material analyzes have been carried out to see if the material has been contaminated with iron, for example by dissolving a cast-iron filler tube or a batch material. From all the analyzes and fractographic investigations carried out, it can be stated that the initiator of crack insertion and the subsequent cracking of the casting under load is the high content of rough fragments of the fractured intermetallic phases of the Al5FeSi type on the fracture surface (over 20%), which are subject to fission. The high iron content was due to the dissolution of the cast iron ascension tube by low-pressure casting.

During the operation, a slewing bearing is always subjected to a set of combined loads. It is the source of deformation of ball-raceway contacts, rings, and even supporting structures. In practice, deformation of rings and supporting structures is often neglected for simplification, that is, they are supposed to be ideally stiff. To take elasticity of rings and supporting (fixed) structures into consideration, the finite-element method (FEM) is applied. In slewing bearings, a great number of contact pairs are present on the contact surfaces between the rolling ele-ments and raceways of the bearing. In order to improve the computational efficiency of load distribution of large roller slewing bearing, a computa-tional model using one-dimensional finite elements (nonlinear elements) is presented in this paper. In this model, each roller is simulated by a group of nonlinear elements truss, which has the same load-deformation perfor-mance with solid roller-raceway contacts. The results show that a group of parallel springs can be used to replace the solid roller and simulate the line contact performance between the roller and raceway. Obtained results are presented as graphs.

Austenitic stainless steels are common spread in many industries. Plasma nitriding is one of the few technologies that allows surface modification of austenitic stainless steels. In this study, a plasma nitriding method to form a hard surface layer at two different austenitic steels AISI 302 and AISI 316L. The surface morphology, chemical composition and mechanical properties of the formed layers were described and the results were compared with each other. The formed nitrided layers on both steels created a uniform multi-phase layer which was characterized by high hardness and very good abrasion resistance.

The test station is used to determine the fatigue of bearings in passenger cars. The influence of prestressing or axial clerance, the reliability of the locking elements for the axial adjustment, the quality of the seating of the outer ring and the change in the type, quantity or distribution of the lubricant can also be examined. The test station consists of a test unit for the simultaneous testing of two test bearings. The misalignment of the wheel contact point and the center of the bearing is fixed by means of mountable parts. The test bearings are clamped between the flanges at both ends of the test shaft, which is supported by two auxiliary bearings. The numerical simulation with finite element method (FEM) deals with the analysis of the bearing test station, which will be loaded by axial and radial loads.

This article deals with benefits of PVD and CVD coatings applied to cutting inserts during face milling technology. The coatings deposited on applied cutting inserts were used to extension the tool life. Machining process was carried out on the conventional vertical milling machine tool. This machining process was performed without coolant. The set up of cutting conditions were constant throughout the machining and low-alloy Cr-Mo steel DIN 42CrMoS4 (W. Nr. 1.7227) was used as workpiece material in the realized process of experiments. The aim of this investigation was to compare coated and uncoated changeable cutting inserts clamped in the milling cutter and find out the benefits of PVD or CVD coatings during realization of face milling process. The monitored parameters were the force load measured by piezoeletrical dynamometer Kistler 9257B and the obtained flank wear measured by optical microscope.

In recent years, significant success has been achieved in surface treatment research, particularly in the field of physics, which deals with the surface properties of metals and their alloys, as well as new methods of coating preparation and thin films. These coatings and layers can modify material properties, i.e. increase oxidation and corrosion resistance, and improve frictional surface characteristics and other physical properties (e.g. electronics and optics). This article focuses on the mechanical properties of the coating, in particular on the hardness of composite PTFE coatings with WC micro and nano particles. In the experiment, samples of different concentrations of WC particles in the PTFE matrix were prepared, followed by a Vickers and Nanoindentation test. The difficulty in measuring the hardness of these layers is their small thickness. It is therefore difficult to measure the hardness by conventional methods, for example, Brinell or Vickers. The applicability of the individual methods (according to Vickers, nanoindentation test) we have experimentally verified and drawn the relevant conclusions and recommendations. Part of the contribution is also SEM documentation of created coatings. An important parameter is the coating technology itself when making these composite coatings. The technology can influence the distribution of particles in the matrix, which results in the homogeneity of the coating and the associated mechanical properties or tribological properties.