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Glass Containing Eu2O3, Tb2O3, Sm2O3, ZnO as a Color Filter Used in the Automotive IndustryAleš Mareška, Tereza Kordová, Martin Havlík MíkaManufacturing Technology 2022, 22(5):573-584 | DOI: 10.21062/mft.2022.071 Over the next few years, LEDs are likely to be responsible for all of the vehicle's exterior lighting func-tions. Everything is focused on maximum security. For this reason, there are more and more automatic color detection systems in the car. Proper color separation is the key to optimal operation and proper evaluation of these automatic systems. An example is the correct detection of traffic light colors. The automotive industry is dependent on consistency and predictability. Classification is an important func-tion for automated control and requires the correct color resolution of the signals captured by the camer-as. We propose to use glass containing various colored active substances such as Eu2O3, Tb2O3 and Sm2O3 as color filters for LED diodes. LED source from one visible light area to another visible light area. This study is devoted to the production of photoactive glass. Subsequently, the photosensitivity of molten photoactive glasses is tested. Both the absorption and excitation spectra of selected photosensi-tive glasses are measured. |
ATF Claddings after High-Temperature Steam Oxidation: WDS and Nanoindentation Studies to Characterize in-depth Material ChangesJitka Klaisnerová, Leoš Křivský, Petra Gávelová, Jakub KrejčíManufacturing Technology 2022, 22(6):703-708 | DOI: 10.21062/mft.2022.078 After the Fukushima accident in 2011 year, ATF nuclear fuel cladding concept was accelerated to achieve the reactor operation with the new accident tolerant structural materials. However, several designed solutions do not fulfil the accident tolerant concept but particularly increase the corrosion resistance of Zr-cladding tubes at normal operating conditions, so-called “Advaced Technology Fuel, EATF”. Cr-coated zirconium claddings following the first concept, have been the widely tested and the first full Cr-coated fuel rods have been planned to operate in LWR reactor conditions around the 2022 year. Our contribution describes the Cr-coated Zr-%1Nb cladding tube microstructure after high-temperature steam oxidation at 1200°C by means of Scanning Electron Microscopy and nanoindenta-tion methods. The article is focused on WDS line-profile studies of oxygen and chromium diffusion into the Zr-matrix. The increased Cr-diffusion with oxygen is evident causing a change in local me-chanical properties which is well-described by measurements of nanohardness and Young's modulus. In addition, the developed methodology of the WDS & nanoindentation line-analyses was also opti-mized to apply in hot-cell conditions to measure the effect of neutron-irradiation on the different coat-ings and coating/matrix interface. |
Ant Colony Algorithms For The Vehicle Routing Problem With Time Window, Period And Multiple DepotsAnita Agárdi, László Kovács, Tamás BányaiManufacturing Technology 2021, 21(4):422-433 | DOI: 10.21062/mft.2021.054 Vehicle Routing Problem is a common problem in logistics, which can simulate in-plant and out-plant material handling. In the article, we demonstrate a Vehicle Routing Problem, which contains period, time window and multiple depots. In this case, customers must be served from several depots. The position of the nodes (depots and customers), the demand and time window of the customers are known in advance. The number and capacity constraint of vehicles are predefined. The vehicles leave from one depot, visit some customers and then return to the depot. The above-described vehicle routing is solved with construction algorithms and Ant Colony algorithms. The Ant Colony algorithms are used to improve random solutions and solutions generated with construction algorithms. According to the test results the Elitist Strategy Ant System and the Rank-Based Version of Ant System algorithms gave the best solutions. |
Influence of Nitrocarburizing on Increasing the Service Life of Elastic Elements of Direct Flow ValvesJan Krmela, Tetiana Hovorun, Kristina Berladir, Artem Artyukhov, Serhii KasianManufacturing Technology 2021, 21(5):647-656 | DOI: 10.21062/mft.2021.071 The effect of the nitrocarburizing process in pastes with heating in a chamber furnace on the struc-ture and strength characteristics of 09Cr15Ni8Al corrosion-resistant steel was investigated. The tech-nology of chemical-thermal treatment was developed, which included nitrocarburizing in pastes with heating in a chamber furnace at different holding times. The thickness of the diffusion layer and its microhardness were determined after nitrocarburizing. To determine the efficiency and select the modes of chemical-thermal treatment, tests were carried out for the investigated steel's strength characteristics. The main feature of the structure of the diffusion layers of valve steels, obtained by nitrocarburizing in the nitrogen-carbon paste, is the presence of an inhomogeneous layer with clearly distinguished zones. |
Study of Light Transmission and Noise Attenuation Properties of Light Active Glass MaterialsPavel Hrbáček, Martin VašinaManufacturing Technology 2022, 22(5):542-549 | DOI: 10.21062/mft.2022.062 Lighting and noise belong to important environmental factors that have an influence on human psyche, concentration, labour protection, sleep quality and so on. This paper is focused on study of light transmission and noise attenuation properties of light active glass materials, which are applied as window and door panels in residential buildings. The light transmission through tested materials was evaluated by means of the transmission coefficient from the illuminance ratio method. The material ability to dampen noise was determined based on the sound pressure level attenuation during sound propagation through the light active glass materials. Different factors, which have an influence on the propagation of light and noise through the investigated glass materials, were evaluated in this work. Finally, the effect of the light transmission through the tested light active glass materials on the daylight quality in a living room was mathematically simulated using Wdls 5.0 software. |
Influence of the Welding Process on the Quality of PVC FramesMateusz Wygoda, Marcin Paprocki, Wacław AdamczykManufacturing Technology 2022, 22(3):356-366 | DOI: 10.21062/mft.2022.037 This paper focuses on the technical and practical aspects arising during the process of window production. One of the phases in the window manufacturing process is welding PVC corners. Therefore, the main subject is flexural strength of PVC welds in the context of the required quality. In the first part of the paper, the authors highlighted the factors and conditions of the welding process and their influence on the final properties. In the next part of the study attention is mainly paid to the temperature control, which is often the cause of quality problems with welding corners. The welding process was conducted with the use of three types of welding machines, i.e. single-, double- and four-head units. In each case, the welding temperature was set in the controller of the machine; at the same time, the contact temperature measurement was taken. The next step was verification of the influence of temperature on the welded PVC corners by measuring the bending force according to PN-EN 514:2002. Additionally, the authors present the DIC (Digital Image Correlation) method used to assess displacements and strains for a selected case in the process of bending PVC corners. The study provides a basis for discussion and remarks about practical advice and identification problems associated with the durability of PVC welding in industrial processes. |
Analysis of Damaged Delimber Knives and the Possibility of Increasing their Service LifeMiroslava Ťavodová, Monika Vargová, Jozef Krilek, Dana StančekováManufacturing Technology 2022, 22(1):80-88 | DOI: 10.21062/mft.2022.011 The article deals with the wear of the blades of the delimber device of harvester head. An input analysis of the materials of the fixed knife and movable arm parts was performed. It consisted of chemical analysis, evaluation of microstructure and hardness measurement by HRC and HB methods. The original welded joint was analyzed, which ensured the connection of the blade and the fixed, resp. movable arm mechanism. Based on the findings, two blade replacement solutions have been proposed. The first was the application of hard metal by an OK 84.58 electrode and second use HARDOX 450 by welding with a fixed part or a mechanical gripping with screws. This was recommended based on previous research at the Faculty of Technology. The hardnesses of the original blade material were compared with the proposed solutions. The correctness of the proposed methods will be verified in the future and in operation. |
Surface Quality of a Groove after Trochoidal Milling with a Monolithic Ceramic Milling CutterSilvia Slabejová, Jozef Holubjak, Tatiana Czánová, Pavol Timko, Andrej Horák, Denis ProkeinManufacturing Technology 2022, 22(3):334-341 | DOI: 10.21062/mft.2022.031 Hard-to-machine materials conclude a variety of materials. In this group of materials are high-strength, hardness-resistant steels, such as austenitic steels, but also non-ferrous alloys with high cor-rosion, heat resistance and strength based on nickel, titanium or cobalt, etc. For machining of these materials, it is necessary to choose suitable tools. The improper cutting tool can cause an increase in geometric inaccuracies, rapid wear, etc. Cutting material is an important factor during designing of cutting tools. A combination of a proper cutting tool with the trochoidal milling can reduce maching time, extend tool lifetime and reduce production costs. |
Analysis of the Effect of Heat Treatment and Corrosion Load on the Microstructure and Microhardness of the Ti6Al4V AlloyIryna Hren, Sylvia Kuśmierczak, Roman Horký, Jaromír MachManufacturing Technology 2022, 22(4):414-422 | DOI: 10.21062/mft.2022.058 In terms of physical and chemical properties, titanium and its alloys are among the most important construction materials today. The Ti6Al4V alloy can be classified among high-strength materials with good plasticity, corrosion resistance and other valuable properties. When performing operations associated with long-term heating of workpieces and parts made of titanium alloys in an air atmosphere, a TiO2 layer is formed on the surface of the product. Ti6Al4V alloy, also known as Ti64, in terms of microstructure is a two-phase alloy formed by α+β solid solutions, which has excellent corrosion resistance and biocompatibility. This alloy is also suitable for jet engines, gas turbines and many aircraft components, as well as in biomedicine. Heat treatment can further improve its technical properties, reduces stress, improves machinability, fracture toughness. The surface of alloys can also be thermally stressed when micro and nano layers of material are applied, which serve to extend the life of products made of this alloy. The presented article analyzes the effect of heat treatment at temperatures of 550 °C and 600 °C and corrosion load with salt fog in the range of 168 to 720 hours on the microstructure and microhardness of the Ti6Al4V alloy. |
The Influence of Fe Content on Corrosion Resistance of secondary AlSi7Mg0.3 Cast Alloy with Increased Fe-contentZuzana Šurdová, Lenka Kuchariková, Eva Tillová, Lucia Pastierovičová, Mária Chalupová, Milan Uhríčik, Martin MikolajčíkManufacturing Technology 2022, 22(5):598-604 | DOI: 10.21062/mft.2022.073 Production of primary aluminium is energetically enormously expensive. The use of secondary (recycled) aluminium, has therefore a high potential to save money and energy while reducing the negative environmental impact of aluminium production. Although the properties of secondary aluminium alloys are generally comparable to those of primary aluminium alloys, the increased Fe content can lead to a significant reduction in the corrosion resistance of these alloys. Secondary (recycled) AlSi7Mg0.3 cast alloy with different iron contents (0.123, 0.454, 0.679 and 1.209 wt. %) in the as-cast and after heat treatment (T6) condition was investigated. The quantitative analysis was focused on the evaluation of the Fe-phases, especially the needle-like Al5FeSi phase. The corrosion resistance was measured by a rapid corrosion test (AUDI test). The corrosion damage of the surface was observed macroscopically. The results show that Fe content higher than 0.454 % has no significant effect on the amount and size of needle-like phases of Al5FeSi. The corrosion resistance is mainly influenced by the size and length of the Al5FeSi phases. Increased Fe content decreases the corrosion resistance of AlSi7Mg0.3 alloy and accelerates the initiation of corrosion. |
Path and Trajectory Planning for an Automated Carrier Vehicle Equipped with two Conveyor Belts used in Manufacturing SupplyÁkos CservenákManufacturing Technology 2021, 21(2):164-183 | DOI: 10.21062/mft.2021.027 The AGVs or mobile robots are well used in today’s manufacturing supply technologies and also can be used in engineering’s education. The motion controlling and simulation of such vehicles are a cru-cial question. This paper introduces the steps of motion planning for a driverless carrier vehicle from the positions initially available to the speed of the wheels. The vehicle is located in the High-Tech Logistics Systems Laboratory of the Logistics Institute of the University of Miskolc. For motion con-trolling and simulation between two points the further modules are necessary: 1. path planner, 2. tra-jectory planner, 3. velocity-voltage converter using velocities gained from trajectory planner, 4. mo-tion controlling and simulation of a motor dynamical model using voltages from the converter, 5. simulation of the path and 6. data processing. In this paper the first two modules are detailed, i.e. the path planning and then the trajectory planning. Path planning is based on a new approach, using Bezier-curves and Hermite curves. The trajectory planning tends to the mininum energy, which can be carried out by the examining the current consumption created in the other modules. The smaller consumption originated from the two curves determines the final path and trajectory. |
Exploring and Developing an Industrial Automation Acceptance Model in the Manufacturing Sector Towards Adoption of Industry 4.0Muhammad Ramzul Abu Bakar, Noor Afiza Mat Razali, Muslihah Wook, Mohd Nazri Ismail, Tengku Mohd Tengku Sem-bokManufacturing Technology 2021, 21(4):434-446 | DOI: 10.21062/mft.2021.055 Technological progress in the 21st century has catalysed the industrial revolution (Industry 4.0) following the development of multiple new industrial automation technologies in the manufacturing sector. Regardless, past research indicated the unsuccessful attempts in adopting Industry 4.0 technologies among manufacturing organisations. Undoubtedly, the operationalisation of Industry 4.0 in manufacturing proved challenging as organisations were required to evaluate various aspects for effective implementation. Thus, a sound understanding of constructs concerning employees’ acceptance and readiness levels towards novel automation technologies was required. Hence, this study aims to explore, develop, and validate the suggested conceptual framework by integrating the Technology Acceptance Model (TAM) and Technology Readiness Index (TRI) with Exploratory Factor Analysis (EFA). The EFA process was the first crucial step in ensuring the internal consistency and stability of the instrument across the sampling population. Consequently, the research outcome potentially enabled the manufacturing sector to identify and comprehend the key determinants in designing industrial automation technologies. This study also contributed to knowledge on technology acceptance by synthesizing TAM 3 and TRI 2.0 theories, thus constructing a new TAM in manufacturing. |
Vacuum System for Reinforcing Fabric HandlingJan Kužel, Roman RůžekManufacturing Technology 2022, 22(2):204-210 | DOI: 10.21062/mft.2022.027 The paper considers questions asotiated with automated systems to produce composite parts. Exist-ing automated systems used in aerospace production are usually based on lay-up technologies. The main objective of the on-going development is to find an affordable production technology for com-posite parts that can be easily automated. The handling with dry reinforcing fabrics is objective of the paper: dry fabric is placed in a suitable mold where it is impregnated by selected type of a matrix and consolidated under vacuum bag afterwards. Based on experiments using standard gripping systems, it was found that local damage of reinforcing fibers occurs. For these reasons, a new vacuum suction-based gripper was developed. As a suction source industrial vacuum cleaner was used, whose perfor-mance can be regulated continuously. Functionality of the suction system was verified on six differ-ent types of reinforcing materials, using two different types of suction grid at three different levels of vacuum cleaner performance. Performed experiments verified suitability of the designed solution for manipulation with dry fabrics without the risk of their damage. |
CoCrFeNiTi High Entropy Alloy Prepared via Mechanical Alloying and Spark Plasma SinteringPetr Kratochvíl, Filip PrůšaManufacturing Technology 2022, 22(4):423-428 | DOI: 10.21062/mft.2022.049 Mechanical alloying and subsequent compaction with spark plasma sintering was chosen for the fabrication of investigated CoCrFeNiTi alloy method. The alloy was characterized in terms of chemical and phase composition with X-ray fluorescence spectroscopy and X-ray diffraction spectrometry, respectively. The microstructure was examined using light microscopy and scanning electron microscopy equipped with an energy dispersion spectrometer. The alloy showed an ultra-fine grained uniform microstructure composed mainly of an FCC solid solution with a volume fraction of HCP Laves phases. Regarding mechanical properties, the prepared specimen reached an ultimate compressive strength of 1340 MPa with the hardness of 757 HV 30. The wear rate of the sample reached 1.19 · 10-4 mm3·N-1·m-1 showing traces of adhesive-abrasion wear mechanism. |
Characteristics of Pinewood Dust Combined with Vinyl Ester Composites Through Material Testing and MachiningMuhammad Wafiuddin Suhami, Norfariza Ab Wahab, H. Boejang, Khairum Hamzah, Hiroyuki SasaharaManufacturing Technology 2022, 22(5):590-597 | DOI: 10.21062/mft.2022.063 Natural fibre-reinforced polymer (NFRP) composites can be environmentally friendly and cost-effective alter-natives to synthetic fibre-reinforced composites. Major industries have expressed significant interest in the advancement of new natural fibre-reinforced composite materials. However, these materials perform poorly on their own and require further analysis since accessible information is lacking in the literature. This paper presents the results of previously reported works on natural fibre reinforced polymer composites, with strong attention to the types of fibres employed, the polymers used in the matrix, the treatment of fibres as well as the test parameters. The best proportion of composites is consequently selected. Composite materials are tested using a CNC router machine. Pinewood dust is combined with vinyl ester resin. A hand layup tech-nique is used to prepare the samples. The availability of relevant pinewood dust and the volume of pine wood dust to be used are first determined to continue with the experiment. According to the findings, the impact of machining performance is successfully evaluated by employing the tensile strength test, Charpy impact test, flexural strength test and surface roughness measurement. The findings are derived from the microscopic assessment of the surface roughness of pinewood dust (PWD) fibre reinforced vinyl ester resin. |
Theoretical and Experimental Study on the Influence of Ultrasonic Vibration on Contact FrictionChangli Zha, Shenlong ZhaManufacturing Technology 2022, 22(3):367-376 | DOI: 10.21062/mft.2022.038 The effects of punch radius, deep-drawing speed and amplitude on the friction coefficient were studied on an improved drawing-bulging friction coefficient testing device on basis of ultrasonic vibration. A contact friction model based on the tribology theory of adhesion and plowing was constructed and used to explain the friction reduction phenomenon of applied out-of-plane normal vibration. The results show that the friction coefficient decreases with the increase of ultrasonic vibration amplitude. At the same deep-drawing height, the friction coefficient decreasing rates at amplitude of 7.8um and 10.1 um on the deep-drawing speed of 0.1 mm/s and 10 mm/s, were 6.7% and 18.8%, respectively. the friction coefficients at the punch radii R0.3 and R1.5 declined from 0.18 to 0.13 and from 0.12 to 0.11. The friction coefficients of thin specimens were larger than thick specimens whether ultrasonic vibration was applied or not. The average friction coefficient from theoretical modeling (μ_v) was smaller than the friction coefficient without ultrasonic vibration (μ_0), and the relative friction coefficient ratio declined with the rise of amplitude and was inversely proportional to time. |
Evaluation of the Strengthening Effect of Different Surface Treatment Techniques in Steel Crankshaft Manufacturing IndustrySongsong Sun, Xiaolin GongManufacturing Technology 2022, 22(6):747-753 | DOI: 10.21062/mft.2022.087 At present, electromagnetic induction quenching and nitriding are two commonly used surface strengthening approaches applied in improving the strength of the steel parts. In this paper, a comparative study was proposed to research the strengthening effect of these two technologies in improving the fatigue strength of steel crankshaft. First a modified statistical analysis approach of the fatigue limit load was proposed to obtain the distribution of the fatigue limit load. Then two types of steel crankshafts were selected to be the object of research and treated by these two techniques. Finally the standard T and F hypothesis testing methods were conducted in evaluation the strengthening effect. The results showed that compared with the nitriding approach, the electromagnetic induction approach can improve the fatigue strength of the steel crankshaft more obviously, thus is more suitable for engineering applications. |
Model of geometric deviations in milling with three error sourcesAndrea Corrado, Wilma PoliniManufacturing Technology 2021, 21(5):575-584 | DOI: 10.21062/mft.2021.078 The milling process is widely used industrially and the quality of the obtained milled products should be controlled because it affects their performance in exercise. This work correlates the quality of the machined surfaces with the adopted locating system, the shape deviations of the workpiece datum and the machine tool. An analytical model was set up and implemented through Matlab® to simulate the quality effects of a milling process. It was applied to two face milling processes characterized by two different locator configurations. It was proved that machine tool volumetric error influences the flatness of the milled surface, while the locator configuration and the datum form deviation affect the orientation of the milled surface, as should be actually. |
Analysis of Parameters of Sintered Metal Components Created by ADAM and SLM TechnologiesPavol Timko, Tatiana Czánová, Andrej Czán, Silvia Slabejová, Jozef Holubjak, Miroslav CedzoManufacturing Technology 2022, 22(3):347-355 | DOI: 10.21062/mft.2022.032 Atomic Diffusion Additive Manufacturing (ADAM) is a recent metal sintering process based on known composite printing technology. ADAM can be classified as indirect additive production using fibre of metal powder bound in a plastic matrix. The plastic binder allows the metal powder to remain in place when is printing. Thus, a "green part" is printed and then the plastic binder is removed by the post-washing and sintering process. The aim of this work is providing a brief description of the ADAM process patented by Markforged. Furthermore, the main task was to compare the technology with other sintering technology, namely SLM technology. It works on the basis of selective bonding of metal powder using the thermal energy of the laser beam. Parameters, such as dimensional and shape accuracy, roughness of printed surfaces or tensile strength of printed samples were examined and compared. Dimensional accuracy of the ADAM process was evaluated using ISO IT grades - determined on the basis of the reference standard. The observed accuracy of the sintering process was comparable to traditional production processes. |
Phase and Mechanical Properties Response of the Mechanically Alloyed CoCrFeNiAlX High Entropy AlloysAngelina Strakosova, Petr Kratochvíl, Jan Riedl, Filip PrůšaManufacturing Technology 2022, 22(4):471-476 | DOI: 10.21062/mft.2022.059 The present work describes the influence of Al content on the CoCrFeNiAl high-entropy alloys pre-pared by the powder metallurgy technique. The preparation procedure consisted of mechanical alloy-ing and subsequent spark plasma sintering. The content of Al varied from 10 – 30 at.% which affected the microstructure and mechanical properties. Using scanning electron microscope (SEM) and X-ray diffraction analysis (XRD) was found the microstructure becomes more refined with increasing con-tent of Al accompanied by the annihilation of the ductile FCC solid solution (Cr0.25Fe0.25Co0.25Ni0.25) phase and growth of the brittle and hard BCC solid solution phase (α-Fe) and formation of Al(Co0.5Ni0.5) phases, improving the mechanical properties. The best combination of the porosity, hardness HV 30, and ultimate compressive strength (UCS) was achieved for the studied high-entropy alloy when it contained 20 at. % Al. |
Ballistic Resistance of Composite Materials Tested by Taylor Anvil TestJindřich Viliš, Zdeněk Pokorný, Jan Zouhar, Miroslav JopekManufacturing Technology 2022, 22(5):610-616 | DOI: 10.21062/mft.2022.074 This study is focused on testing the ballistic resistance of composite materials to define their limit thicknesses according to the US STANDARD NIJ 0101.06, level III. The materials Twaron CT 747, Twaron CT 747 TH110 and Endumax Shield XF33, which are widely used in the manufacture of the ballistic protection systems, were tested. A method known as the Taylor Anvil Test (TAT) was used to verify their ballistic resistance. The missile 7.62 mm M80 was used to test the ballistic resistance of these materials. Within the experimental part, the deformation processes of composite materials were examined after impact by this missile. The value of the traumatic effect according to the US STANDARD NIJ 0101.06 was also measured. The results of the experiment provide an idea of the ballistic resistance of selected materials. Based on the results, TAT proved to be the perspective measurement method for further development and optimalization of the multilayer composite armor. |
Tools for Advanced Control Processes in Plastic Injection Moulding TechnologyEliška CézováManufacturing Technology 2022, 22(6):660-668 | DOI: 10.21062/mft.2022.077 This paper describes some tools usable for quality control in plastic injection moulding. The introductory part presents tools for quality management, the use of which is demonstrated in the next part using a practical example. The selection of suitable methods was based on proven methods for quality management. They were selected to work in synergy. The author's contribution is the modification of the PDCAI method, which was enriched by another step, namely, innovation. The last part of the article presents is a demonstration of FMEA, Ishikawa diagram, and Pareto diagram. |
Kinematic Analysis of the Tram-pedestrian Collision – a Preliminary Case Study.Lubos Tomsovsky, Petr Kubovy, Frantisek Lopot, Karel JelenManufacturing Technology 2022, 22(1):89-94 | DOI: 10.21062/mft.2022.007 The goal of the study was to conduct a preliminary analysis of the kinematics of tram-pedestrian collision in case of a side impact. A T6A5-type tram, traveling at the speed of 10 km/h, was used for the crash analysis and reconstruction of the collision. The pedestrian response was analyzed using a crash-test dummy. For the purpose of this study, the postimpact dummy movement was approximated by the motion of its center of mass (COM) and only the translation movement in the frontal plane of the dummy (along the horizontal and vertical axes) was considered. The results showed a significant change in the coefficient of restitution after the initial impact. At first, the coefficient of restitution was high (e = 0.94), suggesting an almost perfectly elastic collision, followed by a sharp decrease (e = 0.07) within a short period of time (t = 0.02 s) that suggested an almost perfectly inelastic collision. After that, the coefficient of restitution reached a plateau phase with the values ranging from 0.18 to 0.32 and corresponding to a percentage loss of kinetic energy falling within 89 % and 97 %. The preliminary analysis of this study highlighted some features of side-impact tram-pedestrian collision and its kinematics. |
Cutting Forces in the Milling of Difficult-to-Machine Material used in the Aero Space Industry Using a Monolithic Ceramic Milling CutterSilvia Slabejová, Jozef Holubjak, Pavol Timko, Michal Richtárik, Stanislav Krajčoviech, Denis ProkeinManufacturing Technology 2022, 22(2):211-217 | DOI: 10.21062/mft.2022.019 The constantly developing aerospace industry places demands on increasing productivity and produc-tion efficiency. At present, new construction materials are being produced that have better physical and mechanical properties than conventional materials. In addition to new materials, new cutting materials and new machining technologies are being developed. The combination of suitable machin-ing technology, material and tool will achieve excellent product surface quality, long tool life and thus production efficiency. Due to its mechanical and physical properties, technical ceramics can be used in the machining of difficult-to-machine materials, in which there is mechanical stress on blows, impacts, abrasions and other damage. Thanks to these properties, ceramics as a material is very suit-able for the production of machine tools. The presented article deals with the applicability of ceramic milling cutters in high-speed machining of nickel alloy, which is used mainly in the aerospace indus-try. The evaluation of the experiment took place by means of DoE - analysis of cutting forces, the result of which is the creation of the dependence of cutting forces on cutting conditions. Based on the data obtained, it is possible to continue to further intensify the cutting conditions in the area of high-speed machining. |
A Modified Thermal Model of Internal GrindingZhou Chang, Lai HuManufacturing Technology 2022, 22(5):511-518 | DOI: 10.21062/mft.2022.064 In the present study, an innovative method is proposed to improve the accuracy of thermal models of the grinding process. To this end, a set of orthogonal experiments are carried out to calculate heat flux using infrared temperature measurements. Then the convective heat transfer coefficient is modified based on the heat transfer and hydrodynamics theories. Finally, the modified heat flux and convective heat transfer coefficient are applied and a thermal model is established using ANSYS software. To verify the accuracy of the proposed model, a finite element grinding residual stress model based on the grinding heat and grinding force is established. By measuring the grinding residual stress and comparing it with the finite element residual stress model, the effectiveness of the grinding thermal model is indirectly verified. The obtained results demonstrate that the modified grinding thermal models are accurate and can be applied in engineering applications. |
New Principle Schemes of Freight Cars BogiesMykola Gorbunov, Juraj Gerlici, Sergey Kara, Olena Nozhenko, Ganna Chernyak, Kateryna Kravchenko, Tomas LackManufacturing Technology 2018, 18(2):233-238 | DOI: 10.21062/ujep/83.2018/a/1213-2489/MT/18/2/233 In the article the issue of perspective running parts for freight cars of new generation is considered and additions to the outdated existing classification of bogie are developed, namely introduction of such types of suspension is suggested.The results of theoretical studies are presented by means of modeling the movement of the car in the software "Universal Mechanism" to determine the influence of the first stage of spring suspension in Barber type bogie (type 18-100 and analogues) on energy efficiency (resistance to movement) and the estimated value of the decrease in resistance to movement.A concept for a fundamentally new design of a freight car bogie for high-speed traffic has been prepared, based on fundamentally new technical solutions with elastic-dissipative bearing elements, as well as a concept for the modernization of the Barber-type bogie (type 18-100 and analogues) by introducing axle suspension on the 1520 mm gauge. |
Experimental Study of the Process of Radial Rotation Profiling of Wheel Rims Resulting in Formation and Technological Flattening of the CorrugationsRuslan Puzyr, Tetiana Haikova, Ján Majerník, Monika Karkova, Ján KmecManufacturing Technology 2018, 18(1):106-111 | DOI: 10.21062/ujep/61.2018/a/1213-2489/MT/18/1/106 Experimental studies of the wheel rim workpieces with additional technological corrugations have been carried out the results of which showed the ineffectiveness of this technique in profiling to increase thickness of the radial profile junctions of the semi-finished product. The comparison of profiling methods was carried out according to the Cochran's criterion and Student t-test. The additional experiments aimed at the determination of the flexural strain on differently shaped workpieces confirmed the impossibility of creation of the upthrust in the meridional direction during the deformation of the closed shells with straightening of the technological seats (corrugations). It is determined that the seats on the shell unbend in the tangential direction, the bending moments are damped nearthe site of the load application. |
Analysis of the Power Load when Finishing Very Precise Holes by Reaming Head MT3Josef Sedlak, Ales Jaros, Martin Slany, Karel Kouril, Jozef Majerik, Igor BarenyiManufacturing Technology 2018, 18(4):659-666 | DOI: 10.21062/ujep/157.2018/a/1213-2489/MT/18/4/659 Design and technological development of cutting tools represents a fluent process that combines new knowledge from all usable technical branches with actual needs and development results of component base, production technology and machine tools. The main factors which nowadays accelerate the development of cutting tools are constantly increasing demands to improve efficiency and productivity while reducing operation costs, the application of hard machinable materials, environmental protection issues, health and growing demands for greater safety. The article deals with methodology of measurement and evaluation of cutting forces and cutting torque at a special reaming head MT3 from FINAL Tools Inc. Solution of force loading during reaming by these modern tools enable to analyse the causes of cutting tool deficiencies starting from coating suitability up to weaknesses in their design. The article also analyses the significance of the reaming process from the reaming view point using a process liquid, including a tool life analysis combined with the tool wear. |
Assessment of Innovative Methods of the Rolling Stock Brake System Efficiency IncreasingJuraj Gerlici, Mykola Gorbunov, Kateryna Kravchenko, Olga Prosvirova, Tomáš Lack, Vladimír HauserManufacturing Technology 2018, 18(1):35-38 | DOI: 10.21062/ujep/49.2018/a/1213-2489/MT/18/1/35 This paper deals with problem of brake elements unstable operation caused by temperature increase in the friction pair contact during braking. Analysis of constructive solutions for heat dissipation from the brake elements is carried out. It is known that the most used design of ventilated brake disks has disadvantage of creating resistance to movement, which reduces the power of the train. Methods and technical solutions for improving the braking system efficiency by stabilizing the friction contact temperature are investigated. Technical solution dealing with heat removing from the friction surfaces was proposed. Materials with phase transition is used in the design of the braking elements. The expert evaluation system software module in Microsoft Excel was developed to calculate the significance of methods for stabilizing temperature in the friction contact. The expert evaluation results of innovative methods for modern rolling stock brake systems efficiency increase are presented. |
The Heat Treatment Impact on Material Properties of 34CrNiMo6 SteelMariana Janeková, Daniela Koštialiková, Andrej Dubec, Matej Burget, Františka PešlováManufacturing Technology 2018, 18(6):912-916 | DOI: 10.21062/ujep/200.2018/a/1213-2489/MT/18/6/912 An article deals with the assessment of the heat treatment of the material for a particular machine component. This material is 34CrNiMo6, made of two melts. This steel belongs to a group of materials with special properties for working at higher temperatures and for the production of demanding components, turbine wheels, cardan shafts, toothed wheels. The material was evaluated for microstructure quality before and after heat treatment. Based on metallographic microstructures, it is possible to review the heat treatment mode, which subsequently affects the mechanical properties of the components. For a particular design element, better cast material was recommended based on a comprehensive evaluation. |


