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This work deals with the effect of the cutting conditions and the spindle tilt on the surface roughness when grinding complex shaped surfaces of Maraging steel MS1 on an ANCA MX7 5-axis tool grinding machine. It is necessary to grind complex shaped surfaces where high surface quality is important and requested. For this experiment was selected a component with a complex shaped surface which was printed on the 3D printer machine from maraging steel MS1. Since grinding of complex surfaces is being investigated, it is necessary to use CAM software for creat-ing an NC program. The aim of this work is to study the effects of the cutting conditions on the grinding of a com-plex shaped surface in relation to the resulting surface roughness. To do this, it was necessary to design an experi-ment with the appropriate grinding technology, create a clamp, and create NC data in NX CAM software for grinding the complex shape surfaces on the part.

Grinding is one of the basic finishing operations which can be used for parts made from different materials where high quality and surface accuracy is required. One of these materials is maraging steel 1.2709, which is used for the test samples for tensile testing. In this case, it is very important to achieve good surface quality. Wear of a grinding wheel is best expressed as G-ratio which shows us if the grinding parameters are selected correctly. This article deals with the influence of grinding conditions and grinding wheels on surface roughness and wear of the grinding wheels when grinding tool steel VACO 180 on a 5-axis grinding machine. The experiment was designed to investigate the influence of changes in cutting speed, depth of cut and using two different grinding wheels for these two values. At the end of the article, the results from the experiment are summarized and compared.

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 article deals with geopolymer binder system for core production and comparison with PUR cold box amin technology. A sodium-potassium type of geopolymer binder is the subject of the research. The goal of the article is the core production and observing of technological properties, storing cores, usage of refractory coating evaluating of properties during the pouring and decoring of casting. The main target of the experiment is casting quality. It was stated that the final surfaces are much more better than PUR cold box amin technology and the internal casting quality is the same, it means without inadmissible internal defects. Worse decoring times were observed. It has been confirmed, that neither emissions, fumes nor unpleasant odours are generated during the production procedure nor during pouring.

This paper presents a study focused on sandwich structures as well-known train construction materials that are composed of two thin and rigid face sheets and a thick, low-density core material. For trains, the wheel-rail inter-face is the main source of noise, and the wheel-rail roughness, especially in the presence of rail corrugation, is the main excitation source transmitted to the interior and area for passengers. The purpose of the study is to optimize the acoustic properties of a composite sandwich panel used for train floors and walls. Sound absorption coefficient (?), noise reduction coefficient (NRC) and Transmission loss (TL) evaluations have been implemented and experimentally validated on a typical sandwich material used for trains. The opportunity to use a different material can be concretely calculated and modified for critical frequency ranges. Sound transmission loss levels of the structural components as the floor and wall of the train body, which are required of producers and cus-tomers, were tested in acoustic laboratory and acoustic devices according to ASTM and ISO standards. It is demonstrated that, for honeycomb and cork sandwich panels, acoustic response is not sensitive to cell size. For foam core sandwich panels, it is observed that different compositions with thin layers are effective in the fre-quency range of 50 - 1000 Hz.

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.

The aim of the article is to compare the experimental investigation of deflection of the sandwich composite beam with theoretical models. The experimental test specimens were composed of three layers. Skins were made using epoxy-resin-impregnated glass laminates with plain weave. The light weight foam Divinycell H100 was used as sandwich core. The three-point bending test was carried out. Fibre-optic strain gauges, SOFO SMARTape Compact deformation sensors, were used for determining the deflection of the sandwich composite structure. Experimentally obtained data were used for comparison with theoretical models – sandwich theory with the transverse shear, sandwich theory without the transverse shear, laminate theory with the transverse shear and laminate theory without the transverse shear.

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 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.

The article presents partial results of research to increase the service life of snow ploughshares, which are used for winter maintenance of forest transport roads. The main working tool of vehicles - snow plough is the arrow ploughshare. It is made as a weldment. The contact tool, when in contact with the road, is the rake blade, which is subject to abrasive wear. The experiment consisted of analysing the current state of materials, designing and exploring such options that would ensure a longer ser-vice life of the blades. Welding material was designed to be applied to the base material of the blade. Furthermore, the HARDOX 450 was designed for the production of the whole ploughshare. The last design was welding HARDOX 450 with an electrode OK 48.00 with the base material steel 11 484. This proposal is presented in more detail in the article. The hardness of HBW, HV and HRC was measured on the samples and microscopic analysis was performed using light and electron microsco-py. The aim was to determine the quality of the connection of materials, mixing in the connection zone and comparison with the condition on the original blade. It is assumed that a suitable choice of welding electrode or a suitable choice of abrasion-resistant steel can achieve an effective increase in the life of the snow plougshare, whether from a technical or economic point of view.

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.

Generative design is one of the most promising means of new product development in the world. It allows formation of organic structures that brings various benefits, e.g. in the form of savings of material and production costs. Generative design includes several types of technology, topological optimization included. The paper addresses the technology of topological optimization implemented on the support part of the 3D printing pad. The result of optimization is the creation of a new, more suitable design concept through the Altair Inspire optimization software.

NiTi is a shape memory alloy used mainly in medicine. Many applications can be also found in industrial sector. Its properties are considerably determined by structure and phase composition. It was found that production by powder metallurgy method leads to creation of required phase NiTi, but certain amount of hard and brittle phase Ti2Ni is also formed. Its presence in the structure affects mechanical properties of the alloy and it might widen the applicability of material to a new industrial branches. Suitable preparation method of composite material NiTi-Ti2Ni with the possibility to control amount of generated phase Ti2Ni would allow regulation of material mechanical properties.

From the technological viewpoint, the manufacture of forged parts is a very complex process governed by countless interrelated factors, the most important of which include temperature profiles, and magnitude and velocity of deformation. For a forge shop, a well-established and optimized forging process guarantees sound profit. Given the changing demands of the market, the range of products and the associated manufacturing parameters must be updated frequently and rapidly. In most cases, this means production line stoppages and production capacity losses due to new process development and optimization. Using material-technological modelling, it can be carried out in laboratory conditions instead, without interfering with the production. In this paper, several optimization experiments based on material-technological modelling are evaluated using various optical and electron microscopy methods.

A "composite" is characterized as the comibation of two or more materials with diametrically different properties, which result into the creation of a new superior and unique material. This is the most commondefinition that holds true for all composites, however, more recently the term "composite" describes reinforced plastics. Polymers are used in every walk of life now-a-days. They are not even hundred years old, but play the significant role in every sector of life such as sports, defense, medicine, automotive, electrical, agricultural etc. In the beginning, polymers were considered as excellent insulators, but today also conductive polymers are available.. In general, polymers have good water resistance, but there are some polymers with good water absorbtion. Presented article deals with monitoring the changes in the mechanical properties of composites with polymer matrix. Composite has been formed from the PA (polyamide) matrix with glass fibers reinforcement. Mechanical properties, impact strength (Charpy) and micro-hardness (Vickers) have been evaluated on samples of the composite before and after the exposure of UV radiation.

Using innovative methods of heat treatment (HT) for high-strength steels, such as the Q&P process, very favourable ratios of ductility and strength can be achieved. Materials processed by this technology have higher content of retained austenite, and therefore better ductility. This experiment deals with HT of 42SiCr steel. The conventional HT and the Q&P processing are compared with respect to material properties. Metallographic analysis, hardness measurement, X-ray diffraction phase analysis (of retained austenite content) and tensile testing were performed. For the hardened samples, the effects of the cooling rate on their microstructure were assessed and the measured real-world data were compared with the simulations performed in the FEA simulation software DEFORMTM based on the thermocouple records. After a conventional HT, the material showed little sensitivity to the cooling rate. In contrast, the Q&P process with higher quenching temperatures resulted in a higher austenite content and elongation of up to 15 % at a strength of 1800 MPa.

The main aim of this article is to show the possibilities of using tram windscreen impact tests in the analysis of human-machine accidents. Empirical experience shows that these accidents especially affect the head, which is at the same time one of the most vulnerable parts of the human body. Windscreen safety testing follows ECE standards and, inter alia, involves collisions with a headform. With regards to numerical simulations, however, it is essential to be able to determine the material characteristics of windscreens. Here it seems to be advantageous in terms of validity, reliability and the economic cost of using collisions with a rigid body where only the glass absorbs all of the kinetic collision energy. The outcome of these tests is a waveform of the cont act force's magnitude as a function of deformation in the direction the force acts. Along with the time course of acceleration of the bumper and its kinetic energy on impact, this information can serve as boundary conditions to verify mathematical models.

The production of precise castings by investment casting becomes an increasingly important manufacturing technology and many of isues of this method have to be addressed. This paper deals with evaluation of critical points on wax patterns of small blades. After the casting of certain product, the casting had a deviation from the required dimension. Investigation revealed that the effect on the resulting dimensional deviation is not only the casting process but also the wax pattern injection process itself. The engine and turbine blades are one of the most important parts in turbine or aircraft engine machinery. Casting deformation is an important feature of evaluation the quality of the turbine blade. In order to control the deformation of the turbine blade during investment casting, a novel compensation method based on reverse deformation was proposed in this study. The article investigates and evaluates critical points for deformation of the blades after their production on wax-press machine. In addition, the effect of the pre-deformation preparation and the human factor influencing effect during assembly is evaluated with the main aspect of not machining all surface of small blades.

This paper presents a development and design of new multifunctional clamping jaws for thermomechanical simulator. In the article there is presented what the thermomechanical simulator is and what is it used for. The article also describes the requirements for the thermomechanical simulator jaws and how they were achieved. All important parts of which the thermomechanical simulator jaws are assembled and used are described in detail. Finally, thermal simulations of the jaws were performed under operating loads. This technical solution is protected as a utility model registered on The Industrial Property Office - Czech Republic.

An application of external fixator is a surgical method for the treatment of large bones fractures. This method has been proposed already a century ago, but despite the extensive development of science and technology, the fixator is often used in the original state of the proposal. [1] Therefore the patient and surgeons are dissatisfied with high weight and poor mobility of fixator during surgery and healing process. [2] Due to this fact it is necessary to apply new 3D technologies into this field of orthopedics and thus improve the current state of this tool. [3] In an account of this information, the 3D model of a new composite external fixator was created. In the research, the composite fixator was analyzed by the finite element method (FEM). Based on the results of FEM and the surgeon's requirements, the composite fixator was further improved and the final results show that the composite fixator proposed by the FEM is able to transfer the applied load from a patient. Therefore the data indicates that the implementation of composite material will further improve patients comfort, the healing process and the precision of surgery. Based on this fact, the mold has already been manufactured and the process of completing the product has started.

This paper demonstrates the new multi criterion decision making (MCDM) techniques were used, i.e. the weighted aggregated sum and product assessment (WASPAS) technique. This involves the modified air abrasive jet machining (MAAJM) of Nickel 233 alloy using carbide coated nozzle in 3mm dia with three responses are considered as against the process variables of injecting pressure, standoff distance, and abrasive mesh size. The optimal combination of MAAJM process parameter for simultaneous minimization of taper angle, surface roughness and maximization of MRR are injecting pressure of 0.686MPa, standoff distance 9mm and abrasive mesh size 400μm with 3 diameter carbide coated nozzle. The optimal results attained with the WASPAS technique demonstrated to good relation with another technique multi objective optimization rational analysis (MOORA).

In order to successfully acquire knowledge in area of machinery safety for engineering students it is necessary to adopt elementary principles associated with risk assessment. Identification of possible hazards is an important part of risk assessment and engineering students need to take part also in hands-on training to supplement their learning process. It is clear that one major obstacle to improve safety training is the problem of allowing learners to work directly with hazardous equipment. Traditional approach is based on the use of slide show presentations enhanced by animations or videos. This training method is passive in nature and does not allow for an actual realization of consequences resulting from ignoring safety practices during interaction between the student and the machine. In order to improve the educational practice in this context, the Virtual Reality (VR) technologies could be used. The purpose of this study was to conduct a preliminary investigation to determine whether training through VR simulator is comparable to traditional training in developing the skills necessary for performing identification of possible hazards related to lathe operation. The results of this preliminary study suggest that VR based training has the potential to constitute a valid alternative to the traditional training approach.

Determining transformation temperatures of novel steels is an important step towards finding parameters for their heat treatment. In advanced high-strength steels for Q&P processing (Quenching and Partitioning), the crucial processing characteristics are the temperatures of the start and end of austenitization and the Ms temperature. Q&P processing is characterized by quenching from a full-austenitization temperature to below the Ms, and subsequent holding at the partitioning temperature. This leads to martensitic microstructures with retained austenite between martensite needles and to ultimate strengths above 2000 MPa and elongation levels up to 10%. Several AHS steels containing 0.4% C were manufactured and cast for this experiment. Their main alloying additions were manganese, silicon, chromium, molybdenum and nickel. Their transformation temperatures were first calculated using the JMatPro software. The values were validated by dilatometry measurements. Based on these results, a Q&P process route was designed and put to test. The resulting microstructures were documented using optical and scanning electron microscopy. Strengths of more than 2300 MPa and up to 11% elongation levels were obtained.

The article deals with geopolymer binder system for core production, especially by dehydration technology and comparison with PUR cold box amin technology. A sodium-potassium type of geopolymer binder is the subject of the research. The goal of the article is the core production and observing of technological properties, storing cores, usage of refractory coating evaluating of properties during the pouring and decoring of casting. The main target of the experiment is casting quality. It was stated that the final surfaces are much more better than PUR cold box amin technology and the internal casting quality is the same, it means without inadmissible internal defects. Worse decoring times were observed. It has been confirmed, that neither emissions, fumes nor unpleasant odours are generated during the production procedure nor during pouring.

Several models of FDM machines, characterized by different architecture and hardware components, have flooded the market in the last 5 years. As a result, given the high sensitivity of FDM to the specific machine characteristics, the search for optimal printing parameters is a renown problem. This two-parts paper proposes an easy-to-follow and low-cost procedure for the characterization of any given FDM machine. The method allows the evaluation of the effects of a wide selection of FDM process parameters on the quality of 3D printed parts. The first part focuses on the definition of a series of metrics to be measured on a series of test prints to evaluate the quality of the produced parts. Specifically, several effects are considered: dimensional accuracy, small details, overhang surfaces, ability of printing small holes/thin extrusions and overall quality of the prints. The evaluation of seven quality parameters on a single print is made possible thanks to: i) a specifically designed specimen that is made available to the user and ii) a rigorous and repeatable measurement procedure, which are both discussed in the first part of the paper. The second part presents the characterization procedure, the statistical tools used in the experimentation and provides guidelines to be used for the characterization of any FDM machine. The whole procedure is tested on a desktop FDM machine to demonstrate obtainable results.

Previous work has proposed a process for implementing a lattice structure into a milling cutter body based on clustering in the milling cutter with modified main dimensions of a BCC cubic lattice structure cell. A finite element analysis model has been created to predict the strain and deformation in the struts of the lattice. The prediction made according to static loads demonstrates that the concept of a lightweight cutter meets the strength requirements, though its stiffness does not reach the fully-filled version. The methodologies for creating the FE model are described in this paper. HyperWorks with OptiStruct were used for these analyses. Local stiffness could be improved by varying the strut diameter or using a different type of basic cell for the lattice structure in problematic locations, especially in the area of the connection between the shell of the cutter and the lattice structures.

Direct Metal Laser Sintering (DMLS) is a method of additive manufacturing (AM), which builds metal parts in a layer by layer procedure based on a CAD template. The melting of metal powder by an energy beam and successful mastering of the whole manufacturing procedure requires complex management. Physical and chemical metallurgical phenomena occur during melting of the material and the final microstructure depends on many factors. This study investigates the microstructure of struts depending on their distance from the building platform. It is known that metal powder does not allow the dissipation of heat in the same way as molten material due to gas interstitial volume between the spherical particles. Metallography and micro-hardness were investigated on maraging steel 1.2709. Different melting strategies are recognizable in the macroscopic structure of metal alloys. Interesting facts have been discovered, for instance lose molten group or change of hardness depending on a shape of metal cells. In generally, significant differences were not found between individual specimens.

The paper deals with the practical use of matrix model of sustainable development, the MSD (Matrix of Sustainable Development) in Industrial Management and an introduction to possible problems in implementation. The method is based on expert evaluation, the output of the relational matrix are values of importance, resp. the overview of the priorities of the problem, i.e. the individual social requirements and the factors of quality products. The implementation of the MSD model contributes to the holistic understanding of the product's life cycle. The results reveal the model on the one hand in it is the real importance, and, on the other hand, the possible shortcomings of some hitherto unknown factors. The benefit is also involved in research in the field of quality management and a focus on customer requirements.

In the current world, the business faces different challenges, as it was in the 1950th. Today, most of the manufacturing companies have a very strict approach to increasing market needs of Safety, Quality, Delivery and Cost key performance indicators (KPI). To stay competitive, it is needed, that a holistic approach on the improvement of strategic KPIs is needed in order to be successful. The target of this paper is to show the application of the Value stream mapping methodology, used in a case study for a finish good assembly line in an Electronic Manufacturing Facility. The study is showing the improvement of quality, delivery and productivity KPIs over a time period of 3 consecutive years. The result is the increase of production output from 500 pcs/shift to 1050 pcs/shift, decreasing the number of quality returns from 3 to 0 and improving the delivery performance from 95 to 100% against customer requested date.

In this work, the microstructure and mechanical properties of three types of high-speed tool steels (Vanadis 60, ASP 2052 and S 705) were studied. The steel S 705 was made by conventional ingot metallurgy technology, and other types of steels were manufactured by powder metallurgy technology. The studied steels were examined both in the soft state and further in the hardened condition with subsequent tempering. Microstructure of metallographic cuts and fracture areas was studied by electron microscopy. Hardness, tensile properties and notch toughness were determined. Significant differences in the properties of steels in both studied states have been documented.