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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.

This article deals with optimization of the truss structure. A genetic algorithm is used for this optimization. Within the strength calculation of the truss structure a normative assessment of the beam and their buckling stability is implemented. Also, the entire calculation is designed to use only standard profiles. In the first task, the optimization is focused on the weight of the structure, and in the second, on its price. There are also developments using different population sizes for individual cases, which will be described below. At the end of the work, a hypothesis is made for the link between price optimization and weight reduction.

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.

The aim of the work was to assess influence of technological parameters of casting on thickness and continuity of decarburized layer of castings and their mechanical characteristics in order to suggest adjustment in the production process according to discovered results. The samples for experimental work were taken from one type of casting made from steel 42CrMo4. The thickness of decarburized layer was examined on the samples cast at different temperatures of ceramic mould and at different temperatures of casting. Influence of the wall thickness of the casting was also evaluated. It was ob-served that changing temperature of the ceramic mould does not cause a significant change in the decarburized surface area of the casting. The influence of the casting temperature of the metal and the shape of the casting is more pronounced in the formation of the decarburized surface layer. As the casting temperature rises, the thickness of the decarburized surface layer of the casting increases. With the increasing wall thickness of the casting, the surface decarburization layer also gets thicker.

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.

The vertical stability coil is a new set of saddle shaped non-superconducting coil designed for the purpose of improving the control capability of plasma vertical movement. To avoid the electromagnetic shielding and en-hance the response performance, the vertical stability coil is installed in the inner wall of vacuum vessel. The subsequent disadvantage accompanying the benefit is that the coil is under severe neutron radiation. Besides the neutron radiation the coil will also encounter the ohmic heat once it is energized. The temperature rising of vertical stability coil is not allowed to beyond the specific threshold to guarantee the reliability of the coil com-ponents. Thus, the ohmic heat and nuclear heat calculation methods are presented and the detail temperature field is analysed by using ANSYS to check whether or not the coil can bear the thermal load. In addition, the thermal load will result in the thermal stress. To verify whether the thermal stress will lead to the structural damage, the thermal-structural coupling analysis is launched and the stress is evaluated based on ASME ana-lytical design. The analysis results will provide guidance for the local structural optimization of vertical stabil-ity coil.

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 paper deals with the determination of cohesive parameters of adhesive Scotch-Weld DP490 3M. Mode II of cohesive damage were examined. Experimental testing was performed on the test specimens to determine the me-chanical properties of the adhesive according to ASTM D7905. The results of the experimental testing were com-pared with the numerical simulation of the same test. The cohesive parameters of the adhesive were obtained from the numerical simulation. Cohesive parameters of adhesive can be used to design real complex adhesive bonded joints. Cohesive models (specifically cohesive contacts or cohesive elements) are one of the most accurate methods of modeling adhesive bonded joints, so this method is mainly used for parts where it is necessary to ensure suffi-cient strength, such as in automotive, aviation, etc.

Trusses are commonly used structure in industrial buildings, warehouses, bridges, transmission tower etc. The analysis of the truss structure design is necessary in order to ensure stable and economical system. This paper presents application for computing planar truss structures that was programmed in environment of MATLAB App Designer using finite element method (FEM). App Designer is programming environment used for creating computing applications with graphical user interface (GUI). The created application for trusses allows users to create geometrical model of the truss structure and input material data, perform static analysis, modal analysis and to optimize truss structure in order to minimize its weight. To ensure accuracy of results, test calculations was performed using commercial software and compared with results from the created application.

The article presents the results of experimental research on creating the mobile continuous earthmoving machin-ery. Methods for performing field experimental studies and measuring equipment used are described. The article shows the data of experimental research, their analysis, the determination of physical nature of changes in exter-nal load characteristics of the machinery operating equipment. The conducted experimental studies of modern mobile earthmoving machinery enabled to establish its technical capabilities, the characteristics of the power load of the operating equipment when developing the soil. It also enabled to determine the ways and directions for mod-ernizing the operating equipment of machinery. One of the ways is to optimize technological combination of soil cutting, displacement of the developed soil to the unloading area and unloading of the actuator. The research per-formed and the results obtained have enabled to experimentally confirm the effectiveness of the technical pro-posals to create the design of the chain and bar actuators with impulse soil unloading intensifiers for trenchers implemented in the industry.

The paper describes the possibility to streamline the process of modal parameters estimation performed on the washing machine heater. As the shape of the mentioned part does not allow to capture its response to excitation using conventional gages of acceleration, Polytec PDV-100 vibrometer based on laser Doppler vibrometry method was used. Such a non-contact device captures the response in a form of velocity only at one point in one direction. For that reason, the process of modal parameters estimation can be relatively timeconsuming, especially in case if the vibration of the analyzed structure occurs in more than one direc-tion. The authors speed up the process of response capturing using full-field high-speed digital image corre-lation system Q-450 Dantec Dynamics allowing investigation of the displacements in three mutually perpen-dicular directions. Its adaption for experimental modal analysis was ensured by developing an additional software called DICMAN 3D. As the output from the stereo camera system is in a form of 3D displacements in time, DICMAN 3D allows evaluating a single or multi-reference measurement using several algorithms. As the operational temperatures of the heater change due to the chosen wash cycle, the authors used numeri-cal modeling to analyze the influence of the temperature on the heater natural frequencies shift.

This paper mainly studies the hydrostatic turntable of precision milling and grinding compound machining center in aerospace processing equipment, and innovatively designs and analyzes the mesa. It is proposed to replace the traditional 40Cr with imported marble for the mesa. Firstly, the vibration model of the hydrostatic turntable is carried out. ANSYS Workbench software is used to compare and analyze the original and marble materials. In the process, the static characteristics and the difference of first-order modes of the two materials are compared. In addition, the analytical results are used for manufacturing. The results show when the applied force reaches the limitation 29400N, the maximum displacement of 40Cr increases sharply to 8.9406μm; while the marble material reaches 2.6μm. Meanwhile, it is obtained that the power consumed by marble is reduced by 39.12% compared with 40Cr. The weight of marble is reduced by 39.36% compared with 40Cr. Marble is about 21.59% higher than 40Cr in the comparison of vibration mode results

The properties of bonded magnetic materials (RE-M-B /polymer magnetic composites) depend not only on the magnetic properties of powder, but also on the parameters of the consolidation process and the type of binder. Increasing the binder content in RE-M-B /polymer composites could be very beneficial from the cor-rosion resistance point of view, which, unfortunately, is not conducive to the magnetic properties improve-ment. Therefore, a compromise between both trends is necessary to obtain a material with adequate corro-sion resistance with an acceptable decrease in magnetic properties. In the paper the results of research un-der Nd12Fe77Co5B / biotolerant-polymer composites with different binder content have been presented. The research has been carried out on Nd12Fe77Co5B / biotolerant-polymer composites with 20 and 10 wt. % of binder. Due to the possibility of using the magnetic material in restorative medicine, as a binder the bio-tolerable polymeric material has been used (acrylate). All results has been compared to previously deter-mined measurements for composite with a binder content about 3 % wt.. It has been found that the content of 10 % wt. bio-tolerable polymeric material in the magnetic composite is the most favorable (optimal) - the binder material is evenly distributed throughout the composite volume.

Technological conditions of tube drawing influence the properties of the resulting products. In addition to mechan-ical properties, they also affect the geometry of the drawing tube ? macro geometry and microgeometry. The paper presents the results of measurements of macro geometry (roundness and cylindricity) and micro geometry (surface roughness) of the outer surface of the drawn tube. Tubes (STN 41 1353) were drawn through dies with different reduction angles (6° and 12°). On used fixed mandrels were ground the straight and spiral grooves. The effect of these grooves and hence the deformation itself has also been manifested on the outer surface of the drawn tube. On the measured roundness profiles are significantly noticeable places where the land and the groove were when drawing. This effect can also be observed on the deteriorated measured values of roundness. On the meas-ured values and roughness profiles of the outer surface of the drawn tube can also be observed the difference be-tween land and grove.

This paper deals with the design of a multi-part mould for the production of a carbon fibre medium-large compo-nent. The design and forming of a medium-large component which is defined by a closed structure and has high demands on dimensional accuracy is a very complex process. The goal was to design a simple manufacturing pro-cess for a negative mould. There are many different ways to design and manufacture this type of mould. One pos-sible solution was designed and tested. This paper describes the case study of a carbon fibre monocoque of a small racing car. The first step was to define the requirements of the final product and the negative mould. The next step was to design a multi-part mould with one main parting plane and two minor parting planes and define the number of steps needed to build a negative mould. Another problem is how to define the position of the general anchor points that determine the final product. In this case the procedure of transferring the hole from a positive to a negative mould was defined.

In this work the influence of cyclic thermal tistory on the microstructure and mechanical properties of AlSi8Cu2Fe alloy was studied. The commercial aluminum alloy was subjected to a special heat treatment dur-ing which the alloy repeatedly changed from a liquid to a semi-solid state. During this process, samples were taken, and the castings were subjected to another study. Gradual changes in the microstructure, chemical com-position of the alloy, hardness and mechanical properties under pressure at normal temperatures have been documented. With the increasing number of cycles, the content of alloying elements, especially magnesium, decreased significantly, the proportion of casting defects increased, especially hydrogen bubbles, microshrinkage and oxide inclusions in the alloy. These changes also led to a decrease in the mechanical properties of the alloy. A series of samples without cyclic heat loading was also prepared for comparison.

Ti-6Al-4V alloy is the most commercially used material for the production of orthopedic implants. However, despite its excellent properties, it is not an ideal material for use in medicine in terms of vanadium toxicity and relatively high modulus of elasticity. Titanium β-alloys could be a suitable replacement in future years for Ti-6Al-4V alloy, as they have a lower modulus of elasticity and contain non-toxic elements. Some of the alloying elements may even increase the biocompatibility of the alloy. In addition, a progressive 3D printing method would allow custom-made implants with the required properties to be printed. The aim of this work was to characterize the β alloy Ti-30Nb by Selective Laser Melting (SLM) method and to determine its mechanical properties. In addition, heat treatment was applied in order to homogenize the structure. Ti-30Nb alloy was compared in as-built state and in annealed state.

Zirconium fuel claddings act as a first barrier against release of fission products during nuclear power plant operation and interim storage of the spent fuel. During the reactor operation, cladding tubes are exposed to different stress level at elevated temperatures and neutron irradiation in corrosive environment. It causes a material degradation by corrosion, cladding embrittlement by hydrides and radiation-induced damage or radi-ation growth and creep of the fuel rods. The irradiation damage effects mainly contribute to the loss of material ductility. In our study, microstructure of as-received (non-irradiated) Zr-alloys used in LWR (Zr1Nb, Zr-1Nb-1.2Sn-0.1Fe, Zr-1.5Sn-0.2Fe-0.1Cr) were examined by electron microscopy methods. Transmission electron microscope (TEM) was used to describe the microstructure of claddings used in different reactor conditions and identify the radiation-induced damage, which is presented on Zr1Nb irradiated to one standard campaign in the VVER-1000 active zone. Following Electron Backscatter Diffraction (EBSD) method on transparent foils complements the TEM results in larger area, i. e. by grain size and orientation or analysis of local misorienta-tion after irradiation. Radiation-induced damage was observed in Zr1Nb metallic matrix as type disloca-tion loops, presence of radiation-induced precipitates or partial amorphization of the secondary phase particles. EBSD method showed no changes in crystallographic orientation, but a local increase of dislocation density can be affected by neutron irradiation.

In this paper an examination has been outlined a possibility of further generalization respecting the Dudás?s kinematic-mathematical model, which is suitable for the production geometric development of elements of helicoid drive pairs. The positioning of the rolling surfaces of the cylindrical and conical surfaces, as axoids of worms, in the extended model to the projective space under the right conditions, based on the surfaces invariant to projective transformations can be a right extension of the model, as the projective space model includes the Euclidean space model in full. The machining of the conical worm surfaces modelled in this method involves the clarification of the kinematic-geometric relations of production geometry in the Euclidean space model, which shows the possibility of further development of production geometry. The goal of generalization of the mathematical description is the systematization by creating central collinear projective connection between axoids (rolling cones and rolling cylinders). Managing the production geometry of the worms in a system is also a further improvement in manufacturing precision.

This template describes the behavior of products created with additive 3D printing technology. The tested material used to produce the samples was polyactide acid (PLA). PLA is one of the most favourite material for 3D printing. This polylactide acid contains a metal additive. The standard dog-bone shaped samples reinforced with internal ribs arranged in a grid with 20% of the internal volume of the rib-filled sample were tested for tensile strength. The samples were subjected to different types of chemical degradation prior to the test. As a degradation agent, there was used an organic solvents. The result of the research is the effect of the degradation factor on the mechan-ical properties of these samples and possible use in practice, specifically in technology.

A huge amount of waste comes into being from tyres which cannot already be used for their purpose. There are many ways how to utilize this waste but material recyclation is a priority. Waste tyre rubbers can be processed into a form of granulate which can be used into polymeric composite materials. This research deals with possibili-ties of tyre waste composite material utilization in areas distinguished for wear. The aim of the research was an assessment of a usage possibility of rubber powder (RP) coming into being from tyre recyclation process as a filler into a thermosetting matrix from firm Havel Composite applied into composite boards made by a vacuum infu-sion. The research focused on an evaluation of wear by friction against loosely fixed abrasive particles according to GOST 23.208-79, hardness and interaction of the matrix and the reinforcement by means of SEM analysis of the polymeric composite materials reinforced with waste microparticles arisen from tyre recyclation process. Research results proved a positive influence of the filler on the improvement of the wear resistance depending on the size of active rubber powder.

The main aim of this work was to investigate the influence of impurities on the occurrence of interemtalic phases in AlMg3 alloy. The effect of accompanying (admixture) elements was studied, namely: manganese, iron and silicon in various combinations of AlMg3 alloy. There was a high manganese content in one melt for AlMg3, a high iron and manganese content in the second, and a high manganese, iron and silicon content in the third. The reason for identifying and monitoring the occurrence of intermetallic phases in these accompanying elements is their limited solubility in aluminum, where they are practically secreted only in the form of different types of intermetallic phases. These intermetallic phases then reduce the resulting mechanical properties, especially ductility and also reduce the corrosion resistance of the AlMg3 alloy. Decrease of ductility causes consequently worse formability of the material and brittle intermetallic phases initiate microcracks with subsequent cracking of the material

In this paper, the properties of three low carbon steels containing different percentage of manganese (1.5 or 3 wt%) and aluminium (1.5 or 2 wt %) were tested using dilatometric analysis and metallog-raphy. The steels had chemical compositions typical for TRIP (Transformation induced plasticity) steels and the two steels with an increased manganese content already belonged to the third genera-tion of AHS (advanced high strength) steels. The dilatometric measurement was employed not only to determine the characteristic transformation temperatures but also to simulate the heat treatment procedure commonly used for TRIP steels. Resulting microstructures obtained through this simula-tion were evaluated and compared. The two main alloying elements were proved to have a significant effect on the transition temperatures and thus on the processability and overall resulting properties of the material.

Machining technology is a widely used chip technology designed for the production of segmented parts. It is widely used in almost all branches of industry, including the automotive industry. Here, the investigated alloy 2024 is widely used. A critical factor in the current design of many of these advanced systems is accurate knowledge of degradation behavior in the work environment in the context of surface condition after surface machining. If this environment causes surface discontinuities, they will significantly affect the life of the part. Corrosion behavior is considered to be an extremely critical factor due to its effect on the service life of the structure. Due to the many complexities that have developed in relation to surface condition and corrosion, little useful technical information is available. The aim of the article was to determine the effect of the surface condition on the corrosion behavior of alloy 2024. The chemical composition of the alloy was evaluated by spectral analysis. Furthermore, the samples were evaluated by confocal microscopy and the elemental distribution in the microstructure of the 2024 alloy was analyzed with emphasis on the Al2Cu phase distribution. The individual structural phases were performed using a scanning electron microscope with an EDS analyzer. This article is part of a larger experiment that will focus on the subsequent modification of this alloy, in order to change the microstructure and skin resistance of castings.

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.

The basic mechanical properties of structural materials (e.g. yield strength, ultimate tensile strength, uniform and total ductility, anisotropy coefficient, etc.) represent fundamental material characteristics. These parameters are mostly detected by a static tensile test. From the stress state point of view, it is therefore a uniaxial tension stress state. However, the service load usually means acting of wide range of stress states. For this reason, the department of engineering technology at TUL developed a device enabling loading the sample by planar bi-axial loading with the possibility to change ratio of their loading. It is therefore possible to load the material from uniaxial tension to equi-biaxial stretching. The aim of this paper is to determine the change of one basic material mechanical properties (yield strength) based on the adjustment of various stress states - from the conventional uniaxial tensile stress state (static tensile test) to equi-biaxial stretching. The own evaluation is performed on the measured stress-strain curves for the tested aluminium alloy AA6111. The results can then be used not only to describe the effect of stress state on the deformation behaviour of tested material, but can also serve as input data in numerical simulations of forming technologies.

The article deals with the evaluation of interactions between abrasive particles and treated sample surfaces. It represents a summary of the knowledge gained from research the wear of tools for crushing unwanted growths. Samples of materials were tested under laboratory conditions. The hardness of HRC and HV10 was evaluated in the experiment, abrasive wear rate, assessed according to standard GOST 23.208-79. The depth of the track under test disc by using silicon abrasive particles was also evaluated. Furthermore, the hardness coefficient KT relative to the base material of the tool - 16MnCr5 steel and the hardness of abrasive were determined. By comparing the measured and calculated values the heat treatment procedures and hardfacing materials were assessment. By comparing the measured and calculated values the heat treatment procedures and hardfacing materials were as-sessment, which are expected to provide an increase the abrasion resistance towards to an abrasive, heterogeneous working environment in operation.

This article deals with the design optimization of the mechanical crank press. These presses have not any signifi-cant development changes in a long time. Mechanical press LDC 250 with nominal force 2.5 MN (250 tons) was considered as an example. This type of press can be used for operations such as bending, drawing or cutting. The topology optimization was used during this research. This papers show advantage of this design method. The op-timized press has lower maximal Von-Mises stress in the structure and the maximal displacement is up to two times lower. The research was focused on the main frame (open frame with shape ?C?) of the press. The resistivity aga-ings vibrations was improved. The weight of the frame was not changed. The CAE tool NX Nastran and the opti-mization tool Frustum were used here. The workflow of the topological optimization is deeply described here. The comparison between the conventional (initial) and optimized design shows new approach to these machines.