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The article deals with the application of computed tomography in dimensional quality control. The advantage of computed tomography is that the measured part is not influenced by measuring force. It is possible to measure complex parts and assemblies, their geometry, internal structure and defects in one step. The disadvantage of CT is decreasing accuracy and resolution when measuring hi density materials or larger parts, which leads to usage of high accelerating voltage and current. The measurement result is influenced by many factors, not only the instrument itself and the set of measuring parameters, but also largely depends on the sample itself, on its material and geometry. Based on the requirements for dimensional inspection, an analysis of the dependences of individual parameters of the Zeiss METROTOM 1500 computed tomography was conducted. The dependence of the spot size of the X-Ray source on the accelerating voltage and current was determined for the given instrument, as well as the relation between the voxel size and the distance of the sample from the detector. Spot size and voxel size has to be in relation, since large spot size goes against high magnification, high resolution meaning small voxel size. Using calibration artefact, the influence of the acceleration voltage on the accuracy when measuring form and size of a sphere and the distance between centres of 2 spheres was evaluated.

Observation and identification of products of transformation of austenite during austempering, Q-P processing, or quenching and tempering are often challenging. The reason is that the resulting microstructures are typically very fine and provide insufficient contrast between microstructural components. Their analysis requires scanning or transmission electron microscopy which demand rather complex sample preparation procedures and involve high costs of maintenance of microscopes and accessories. However, in-process inspection of products of heat treatment calls for simpler and rapid methods of microstructure analysis using a light microscope.

The geometric accuracy is significant property of the product. For semi-finished products, this accuracy may also affect the accuracy of the final product (the resulting mechanical component). Geometric accuracy (inaccuracy) can be transmitted from one operation to the next in production - technological heredity arises. It is, therefore, essential to analyze the deviations on the produced areas and take measures to ensure that the negative effect of one operation was not transferred to the next operation. It is insufficient to analyze only the numerical values of the measured deviations. It is necessary to directly analyze the measured profiles in the field of macro geometry. The paper presents a stability analysis of roundness profiles measured on the drawn tube. The analysis uses knowledge from harmonic analysis and from the Fourier series. The measured roundness profiles are divided into individual harmonic components. Arithmetic means of amplitudes of individual harmonic components are moni-tored. There were analyzed parameters determining the stability of the profile - standard deviations.

This paper focuses on the implementation of principles of Industry 4.0 concept to the ceramic industry. The topic of this paper is to address the problematics of the implementation of processes and elements of digitization within the Industry 4.0 concept into the ceramic industry. Firstly, thorough literature and best-practice research will be discussed. Based on the state of current knowledge, the concept of the Industry 4.0 Readiness Model for Refractory will be presented. The model’s main focus is on the readiness of current business structures, processes and technical and economical situation. It will provide the necessary analysis and insight into the potential company’s processes and background. Based on this analysis, it will be possible to define the main obstacles for future digitalization and automation within Industry 4.0 the concept in Refractory industry. On the foundation of data obtained by Industry 4.0 Readiness Model for Refractory, it will be possible to implement the Industry 4.0 solutions with the highest added value to a specific company, based on its current state. The main purpose of this paper is to summarize and discuss key parameters and framework for Industry 4.0 Readiness Model for Refractory and its connection to future implementation of Industry 4.0 features within the ceramic industry.

The aim of the paper is to introduce the digital twin concept as part of the Industry 4.0 strategy. In the form of a case study, the procedure and outputs of the simulation of a specific production plant to-gether with its intermediate storage and output for the next plant are presented. In the research part is presented a simulation model of production lines and intermediate stock with material flow represen-tation. At the beginning of the research the analysis of production and logistics processes was carried out. The next part describes the programming methods used to record and redirect material flows between individual lines and stock. The simulation method using simulated production line models enables the digitization of dynamic production processes in enterprises. We expect that in the coming years there will be an increase in demand for the creation of simulation models of production systems in modern manufacturing companies that will try to implement the Industry 4.0 strategy and thus in-crease their competitiveness.

High-strength X3NiCoMoTi 18-9-5 maraging steel belongs to highly researched materials due to its wide application range. Thanks to its outstanding mechanical properties, it is usually used for high-loaded parts in the aircraft and aerospace industry. Hardness and ultimate tensile strength are strong-ly affected by heat treatment allowing to create Ni3X (X = Mo, Ti), Fe2Mo, and (Fe, Ni, Co)3(Ti, Mo) precipitate which almost doubles their properties. In the present study, microstructure and mechani-cal properties of the thermo-mechanically processed maraging steel were studied two modes of heat treatment. Microhardness values improved from 350 HV0.1 to 650 HV0.1, and ultimate tensile strength has increased from 1029 up to 2140 MPa. On the contrary, elongation has reduced from 11 to 4 %. After heat treatment, precipitates Ni3Mo has been formed in the material volume.

Plasma cutting is an ever-evolving method of industrial cutting of materials. Like all modern methods, it must meet the requirements for the quality of the cut, but also the hygiene and safety regulations set by European legislation. New ways are being sought to reduce process noise while improving the quality of the cutting surface. The article aims to compare two cutting modes (Contour Cut and Silent Cut) in terms of both the quality of the cut (roughness of the cutting surface, size of the heat affected area, perpendicularity and bevel angle of the cutting surface) and in terms of noise of the cutting pro-cess. The results in the article clearly show that the use of the Silent Cut mode has a demonstrably positive effect on the level of noise produced but also on the quality of the cut.

Ceramic composite materials based on boron carbide were hot pressed utilising in situ reaction of boron carbide powder with 40 wt.% of titanium dioxide sintering additive. The samples were prepared at sintering temperature of 1850 °C, pressure of 35 MPa, and time of 60 min in vacuum atmosphere of about 20 Pa. Optimisation of sintering regime concentrating on both heating stage of sintering and application of pressure enabled to prepare fully dense ceramic composite materials composed of boron carbide matrix with 29.5 vol.% of titanium diboride secondary phase. The ceramic composite reached average density of 99.3 %, hardness of 29.8 GPa, and fracture toughness of 6.9 MPa.m1/2.

During the last years, due to the dynamic development of the non-contact measurement methods, there has been observed still increasing number of their applications in various fields - not only in the engineering industry. E.g. from the dimensional quality point of view, knowledge of real 3D data of a given part is truly very important. There are several options for obtaining these data such as the usage of optical 3D digitization or computed tomography (CT). However, within the mutual comparability of such data, it is very important to know not only the accuracy of acquiring 3D data, but also e.g. possibilities of these systems in terms of own measurement. In the paper, a specially designed part containing various convex and concave shapes was measured by using two different systems (ATOS TripleScan optical 3D scanner and METROTOM 1500 G2 CT scanner). The resulting scanned models were then compared not only in terms of dimensional accuracy, but also in terms of quality and detail of the obtained data or the time required to prepare the measurement and its implementation.

Milling is one of the oldest methods of metal machining. This technology has been developed over a long time. The last milestone is the use of composite materials for the construction of cutting tools. However, there are other pos-sibilities for improvement offered by new production methods such as Metal Additive Manufacturing. The paper deals with machining experiments using a lightweight milling cutter with a lattice structure. The results of machin-ing are compared to the capabilities of a solid milling cutter. The evaluated parameters are: cutting forces, blade wear and surface roughness of the workpiece. Based on these parameters, it was not possible to confirm the benefit of the lightweight version for machining.

Currently, companies have been trying to make the use of their technology, manufacturing capabilities and experienced workforce to respond flexibly to market demands. Collecting and processing of all relevant data in the company is one of the key points to which increased attention should be paid so as to maximize the efficient use of own resources and consequently ensure a continuous reduction of pro-duction costs. The article deals with the use of burning machines in engineering company. The product range involves the production of burnouts from standard and special materials as well as welded steel parts of structures. The company has long struggled to optimize the material and information flow between particular production operations. This paper was focused on information flow logistics, which proved to be the biggest weakness of the central material preparation department during the bottleneck analysis. The scientific contribution of the resolved issue can be seen mainly in the possibility of inter-connecting process analysis and optimization of material and information flows.

Scratching force is a significant factor to evaluate the characteristics of single diamond grit scratching process. In this paper, experimental study was carried out to investigate the vibration characteristics of force signals during the scratching process. A precise multicomponent dynamometer is employed in the force measurement during a single diamond grit scratching on pure copper. The frequencies of the vibration section of force signals with different scratching parameters are calculated and analyzed. The influence of force signal vibration on the measuring accuracy of dynamometer is systematically analyzed further. The results show that higher scratching speed and larger scratching depth lead to larger vibration amplitudes of the force signals. Strong impact on the quartz piezoelectric crystal of dynamometer, which is produced indirectly by single diamond grit scratching process, leads to the vibration of scratching force signal. The first semi-sinusoidal force signal is the actual scratching force. The vibration of the scratching force signal has little effect on the measuring accuracy of the dynamometer.

Zinc is one of the most promising elements for the preparation of biodegradable metallic implants. Despite low mechanical performance for load-bearing applications, the degradation characteristics of pure zinc belong to the best from all significant biodegradable metals (Zn, Mg, Fe). The enhancement of the mechanical properties is often reached using various methods of material processing, leading to grain refinement and subsequent enhancement of the mechanical properties. In this study, the microstructure, phase composition and the possible mechanisms of intermetallic phase formation in the ZnMgCaO alloy prepared by high energy ball milling and consolidated by extrusion were studied. Formation of the Mg2Zn11, MgZn2 and CaZn13 phases during the material processing was confirmed. The creation of the phases was, with high probability, significantly affected by the magnitudes of individual components of internal energy. The increment of the internal energy led to the formation of stable Mg2Zn11 phase as well as to CaZn13 formation. Based on our results and the characterization of the microstructure, the most suitable conditions for the preparation of a ZnMgCaO alloy were found.

This paper discusses the possibility of increasing the surface load capacity in C60E steel gearings by applying DLC thin coating. It describes the effect of tribological characteristics, such as friction coefficient, wear, adhesion and hardness of DLC coating on convex-concave gearing (C-C). The average thickness of DLC coating is 1.2 μm. Delamination of the DLC coating was recorded at a load of approximately 50 N. The friction coefficient of the DLC coating was 0.09. The nano-hardness of the DLC coating was 14.4 GPa. The results of the tests to scuffing on C-C gearings on the Niemann tester show that the DLC coating deposition occurred at load level 5. The complete removal of the coating was preceded by gradual thinning. After its removal, the wear continued substrate, where the traces after milling filled-up with the substrate metal.

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.

The paper is focused on the polymorphic transformations of selected steel types. Generally, when creating CCT diagrams, the transformation temperature values Ac1 and Ac3 are determined under at very low heating rates (max. 0.1 °C?s-1). The only exceptions are so-called in-situ CCT diagrams, which are determined based upon the real temperature cycles. However, in the case of dynamic processes such as welding technology or heat treatment with magnetic induction heating, cannot be used information from conventional CCT diagrams. Incorrectly selected temperatures lead either to incomplete austenitizing during heat treatment or to a different development of phase transformations in HAZ of welds. Especially, when these processes are carried out without soaking temperature. That is why as the main aim of this paper was to determine the heating rate influence for steels S460MC, S690QL and X23CrMoV12-1 on the shift of their transformation temperatures Ac1 and Ac3. The in-tensity of the heating rate effect on the transformation temperature depends on the steel structure and amount of alloying elements. Consequently, steels with different structures, different type of processing and mechanical properties were deliberately selected to make the assessment as complex as possible.

Steels which are used for manufacturing of highly stressed parts of military equipments such as barrels of small arms weapons must be modified by heat treatment due to achieve required mechanical properties. Moreover, other important properties of functional parts, especially a friction coefficient and surface pa-rameters of bore of barrels, must be optimized due to obtain the best accuracy in target and to increase the life time of barrel [1, 2]. The technology chromium plating, very widespread in the past, has been gradually replacing by more ecological nethods. This article is devoted to find a technology as a replacement of tradi-tional chromium plating. Experiments are focused on using of optimized gas nitriding processes for surface treatment. As a result, a higher surface hardness with low influence on the dimensional accuracy is expected. Gas nitriding process was applied to steels 42CrMo4 and 32CrMoV12-10 used for barrel manufacturing. The most important parts of barrel were evaluated, especially surface parameters as a morphology than chemical composition and naturaly a microstructure of the material. The analysis of surface morphology were performed by scanning electron microscopy; chemical composition was evaluated by GDOES method and mechanical properties by using microhardness methods. The measurements of depth of diffusion layer were performed by destructive and non-destructive methods. The measurements showed the influences of chemical composition of alloying elements in core of material after chemical-heat treatment process on depth of diffusion and influence of technology on development of porosity. All fundamental mechanical prop-erties significant for requiring function of barrel were documented [1, 2]. Nevertheless, the main task was the description of the porosity development in compound layer after gas nitriding and the increasing of sur-face hardness and the depth of diffusion layer according to chemical composition. Nitriding process was ap-plied for increasing of surface hardness of material in depth and improving of mechanical properties. Me-chanical properties of tested material were significantly increased.

Titanium alloy Ti6Al4V falls into the group of alpha-beta titanium alloys and its widely used for engineering application due to its unique mechanical properties in regular or corrosion environments. Mechanical properties of alloy are strictly depending on final microstructure. The microstructure can be varying by various heat-treatment procedures. Heating slightly over beta-transus temperatures, 1050°C, with a dwell of 3 hours and cooling by various rates provide a wide possibility of microstructure modification. The cooling rates were represented by water quenching, air cooling, and furnace cooling. The microstructure has changed from the lamellar alpha-phase in prior beta-grains, through Widmanstätten microstructure to lamellar alpha prime-martensite structure due to cooling rates. After applied heat-treatment, the Vickers hardness HV10/10 (STN EN ISO 6507) and Vickers microhardness HV0.2/10 (STN EN ISO 6507) were done. The hardness and microhardness test results were compared to the starting stage. The Vickers hardness increases in all states about 8% for furnace cooling, 18% for air cooling, and almost 40% for water quenching. The same situation was for Vickers microhardness which increases about almost 29% for furnace cooling, 16% for air cooling, and 25% for water quenching. The hardness measurement shows increasing mechanical properties after all cooling rates. However, heat-treatment also shows negatives by creating the alpha-case layer and surface cracks, which is negative for the fatigue life of Ti6Al4V alloy.

This research pertains to rock cutting used negative rake angle. The parameters used are negative rake angles of 0o, -5o, -10o, -15o, -25o, -30o, and -40o. Negative rake angle is known to play an important role in rock machining. Negative rake angle produces more chips powder in front of the tool surface. The interaction between these particles affects the thrust force that suppresses the rock surface. A large thrust force generates hydrostatic pressure around the tooltip. According to the findings of this research, negative rake angle -25o leads to the largest thrust force and smallest surface roughness for 15.17 N and 1.21 ?m, respectively with smooth and uniform chips. The rock surface and the resulting chips powder was observed by scanning electron microscope (SEM) in order to prove the effect of hydrostatic pressure working on the tooltip. Meanwhile the hydrostatic pressure changed the brittle cutting mode into a brittle-ductile cutting mode.

CFRP (Carbon Fiber Reinforced Polymers) are often used when designing parts that need to be stiff, light and thermally stable. These benefits are a big motivation to use CFRP in many applications, one of them could be sports optics. However, optical devices require precise dimensions with tight tolerances for the opti-cal assembly to work correctly. In order to determine if CFRP could be a suitable material of choice for sports optics a simplified body of binoculars was designed. The main purpose of this prototype was to prove the possibility of using CFRP in binoculars. The tubular body was manufactured by prepreg lay-up into a 3D printed mold, followed by curing in an autoclave. After the prototype was manufactured 3D measurements of the tube using 3D scanner GOM ATOS were made. As expected, shrinkage of the mold and the epoxy resin in the matrix of CFRP caused minor deformations. However, if the shape of the cured part remains unchanged during conditions similar to the general use of binoculars, then the initial deformations happening during manufacturing could be accoun-ted for when designing the part. Other than the carbon part itself, the bond between metal and composite components is another potential point of failure in terms of desired precision. Because of that measurements and tests of concentricity of ad-hesive joints are being currently performed. The results of these tests and others that will follow will indicate if composite materials could be used as a structural material for sports optics.

Processing of synthetic diamonds is accompanied by low productivity and high values of relative con-sumption of diamond wheels. The coefficient of use of diamond grains in these processes does not exceed 5-10%. Using synthetic diamonds as a blade tool, requires sharpening and refinement. This study proposes to use ultra-high-speed machining modes and the same diamond grinding wheel at all stages of tool shaping. At the first stage, i.e. at high speeds, a rough productive sharpening of dia-mond blade tool is made with a wheel on an iron-based binder. At the second stage processing speed is reduced, as a result grains cease to self-sharpen and to wear out. When the iron binder comes into contact with the sharpened diamond, the speed must be increased, so that the temperature in the contact zone of the binder with the rough surface of the cutter, increases. Due to diffusion wear, from the surface of the diamond, the height of the roughness micro-hills decreases. In other words, the process of high-quality thermally activated refinement of the working surface of the diamond cutter starts to be implemented.

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 use of lathe chucks in machine building companies is the result of a great deal of work and the develop-ment of technical thought. Due to the progress and the possibility of increasing efficiency and at the same time relieving people from work that requires a lot of effort, especially physical effort, the use of better and more efficient production methods is a target that should be pursued nowadays. In the manufacturing pro-cess, these objectives can be achieved with the use of dedicated equipment. The following work will present an example of a lathe chuck specialized in turning operations. The aim of the work was to use a universal chuck as a base for designing and manufacturing a specialized chuck so that it is possible to mount rope wheels with diameters from 240 to 580 mm. This would eliminate the necessity of time-consuming changeo-vers. In addition, it is assumed that the handle must meet the conditions imposed by the limited number of tools and the working dimensions of the machine. The machining process itself was also important, where the most advantageous solution was to perform most of the operations in one clamping.

Q-P process is one of the latest techniques for heat treatment of high-strength steels with increased silicon levels. It is believed to be based on diffusion and migration of carbon between martensite and untransformed austenite, where the latter becomes enriched with carbon, and therefore becomes thermodynamically stable. However, the question remains whether much of the carbon partitioning in the Q-P process might be the result of the competing bainitic transformation induced by arrested quenching below the Ms temperature. This paper explores the use of dilatometry for identifying the products of austenite decomposition during Q-P processing of medium-carbon 42SiCr low-alloy steel.

Nowadays, to reduce vibrations of machines, damping devices utilize the eddy current damping ef-fect being increasingly investigated for its advantages of no mechanical contact, no viscous liquid required, high reliability, and good damping capacity. This article studied the main principle of the eddy current damping effect for a moving permanent magnet in a stationary and electrically conduc-tive nonmagnetic cylindrical tube. The magnetic damping coefficient is investigated experimentally, analytically, and by numerical simulations in a steady-state. The numerical simulation is performed in the ANSYS Maxwell programme. The obtained results indicate that the damping force affecting the moving magnet has a viscous form. The experimentally measured and computed results are in good agreement. The effect of varying tube diameter and the tube wall thickness on the magnetic damping coefficient is shown. The contribution of this article consists in the development and a comparison of the obtained results of three approaches for determining the magnetic damping coefficient for a mov-ing magnet in a cylindrical tube.

At the present time, mechanical vibration is undesirable in many cases. Therefore it is necessary to minimize unwanted vibrations in any appropriate manner. This paper is focused on a study of factors influencing vibration damping properties that were investigated using multilayer composite structures. Frequency dependencies of the displacement transmissibility over a frequency range of 2?1500 Hz were determined by the method of forced oscillations. It was found in this study that the vibration damping properties of investigated multilayer structures are significantly influenced by number of material layers, excitation frequency of mechanical vibration, applied materials in multilayer structures, inertial mass, material thickness and density. It was also observed that a superior ability to damp mechanical vibration leads to a shift of the first resonance frequency peak position to lower excitation frequencies.

Technology of adhesive bonding belongs to prospective bonding methods. The limit of adhesive bonds is cyclic loading which usually significantly decreases the service life of adhesive bonds and causes deformation of adhesive and cohesive bonds inside of adhesives. The article deals with the research of adhesive bonds exposed to cyclic loading. The aim of research was establishing an influence of the filler based on meshed coffee beans waste added into two-component epoxy matrix for bonding. The differences of mechanical properties of adhesive bonds with filler based on meshed coffee beans waste were evaluated at static and cyclic loading with 1000 cycles at first interval loading between 5 to 30% and second interval 5% to 70% of the static shear tensile strength.

In the production of a new generation of customized implants, additive manufacturing (AM) is a hot topic. A titanium-based alloy, Ti6Al4V, is one of the most used materials for such applications with regard to its excellent biocompatibility and high mechanical properties which provide it with the capability to bear physiological loads. However, its resistance to wear is rather poor which might cause undesirable loosening of wear particles or even implant failure. Therefore, enhancing wear resistance is desirable. Thanks to a distinctive principle and rapid cooling, AM is known to be able to enhance mechanical properties. In this paper, we thus discuss tribological properties in direct relation to microstructures resulting from AM. We reveal the finest microstructural details of Ti6Al4V alloy prepared by different techniques of AM and discuss also the effect of heat treatment. Complex characterization including transmission electron microscopy, hardness measurement and ball-on-plate wear tests showed a mild contribution of AM to wear resistance of the Ti6Al4V alloy compared to the conventionally produced alloy.

With the determined parameters of cutting speed, feed rate and back cutting depth, cemented carbide tool was adopted to dry cut 304 stainless steel, exploring the tool wear failure mechanism and its effect on the surface quality of the workpiece under different cutting times. The morphology of the tool surface is observed by scanning electron microscopy, and the component of the tool is analyzed by energy dispersive spectroscopy. The three-dimensional microscopic shape of workpiece surface is observed by a three-dimensional shape analyzer and the surface rough-ness Ra was measured. The results indicate that during the process of 6-minute cutting, the abrasive wear and adhe-sion wear are occurred on the tool, the surface quality of the machined workpiece is good; during the process of 12-minute cutting, oxidation wear is appeared while the tool subjects abrasive wear and adhesion wear, and the surface quality of the machined workpiece become pool; during the process of 18-minute cutting, the tool is under the com-bined action of various wear mechanism. Because of the passivation of tool nose, the surface quality of the work-piece is deteriorated, and it can’t meet the requirements of finish machining. In the process of dry cutting workpiec-es by cemented carbide tool, the tool suffers abrasive wear, adhesion wear and oxidation wear. The surface quality of the workpiece is declined due to the passivation of the tool nose.

The heat treatment of the heat-treatable aluminium alloy forgings includes cooling from the solutionising temperature. After heat treatment, residual stresses remain in the forging, which are due to temperature gradients during cooling. The effect of these residual stresses on the forging properties can be significantly influenced by other technological operations, including artificial aging, machining, and surface treatments. The influence of the surrounding environment can also play an important role. Because in connection with the residual stresses after heat treatment we often encounter cracks in forgings, this paper is devoted to an overview of factors that influence cracks. The typical examples of damaged forgings are discussed and explained the circumstances that caused cracks under the influence of residual stresses.