Technológ

Permanent URI for this communityhttps://drepo.uniza.sk/handle/hdluniza/549

Vychádza spravidla dvakrát ročne. Publikuje vedecké, výskumné, odborné, teoretické práce, návody, štúdie, recenzie, informácie o spracovaní technických materiálov. Zameriava sa na uverejňovanie príspevkov a prác venujúcich sa otázkam z oblasti trieskových a beztrieskových technológií, fyzikálnych princípov, nekonvenčných technológií, technologickosti konštrukcií nástrojov, ekonomike výrobného procesu, ekologizácii, spracovaniu odpadov. Takisto publikuje práce o strojoch, nástrojoch, prípravkoch a meracej technike pre oblasť mechanických technológií, výsledkoch výskumu vo sfére informačných technológií v technologickej oblasti. Uverejňuje práce o histórii a vývine mechanických technológií. Časopis zverejňuje príspevky v jazykoch: slovenskom, českom, poľskom, ruskom, anglickom a nemeckom.

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Accompanying phenomena during casting of aluminium alloys
(University of Žilina, 2023) Galčík, Marek; Brůna, Marek; Medňanský, Martin
An oxide layer is formed on the surface of a molten aluminium alloy when it is exposed to the surrounding atmosphere. The oxide layer on the surface of the melt is not harmful. The problem occurs when it is entrained into the melt volume and solidifies in the casting. The paper deals with the formation of the oxide layer, its types and the formation of a double oxide layers.
Analýza jazdných vlastností modifikovaného vozidla a jeho komponentov v dôsledku zmeny pohonného ústrojenstva a ovplyvnenie vzájomného pôsobenia kontaktu koleso/koľajnica
(University of Žilina, 2023) Dižo, Ján; Ishchuk, Vadym; Lovska, Alyona; Blatnický, Miroslav; Solčanský, Sebastián
The presented article is focused on analysis of running properties of a modified railway vehicle and its components due to a change of the powertrain and influence of the mutual effects in a wheel/rail contact. The modification of a vehicle consists in a change of a standard diesel-electric powertrain by a new powertrain, which includes as a source of power the hydrogen fuel cells. This modification represents a quite significant modification of a vehicle structure, mainly a change of mass and position of centre of gravity individual articles of a vehicle. The analysis of running properties is performed by means of simulation computations in a commercial simulation software Simpack. Simulation model of a vehicle is called as a multibody model. This model consists of rigid bodies, which are connected by flexible modelling elements. Simulation analyses are performed for an original vehicle and for vehicle with hydrogen fuel cells. There are analysed cases of running on two types of tracks. There is found oud based on the obtained results, that the modified vehicle with the hydrogen cells has similar force distribution in a wheel/rail contact, however, the axle load of the modified vehicle does not meet required criteria.
Analýza pozdĺžneho zaťaženia kontajnera so stenami vyrobenými zo sendvičových panelov
(University of Žilina, 2023) Vatulia, Glib; Gerlici, Juraj; Lovska, Alyona; Krasnokutskyi, Yevhen
The article presents the results of determining the longitudinal dynamic load of a container of standard size 1CC with sandwich panel walls. A mathematical model was developed that takes into account the longitudinal load of a container placed on a platform wagon during a displacement collision. The use of sandwich containers as components was found to contribute 10 % to the active container design in the longitudinal plane compared to the typical design. A calculation of the strength of the container was carried out. At the same time, the maximum voltages are 18.6 % lower than permissible. Conducted research in preparation for the creation of recommendations for the design of modern modular vehicle structures and increasing the production of the transport industry
Analýza súčasného stavu problematiky využitia manipulačných zariadení pre potreby skúšobných stavov brzdných komponentov koľajových vozidiel
(University of Žilina, 2024) Molnár, Denis; Blatnický, Miroslav; Dižo, Ján; Lovska, Alyona
The paper deals with the current state of the art of the research test stands of braking components of rail vehicles in synthesis to the need of handling equipment utilisation accompanying the research in question. The compact form of the introduced information will be the input material for the design of an original handling device, sophisticatedly designed for the needs of the test stand for rail vehicles brake components testing. The brake test stand is located at the Department of Transport and Handling Machines at the Faculty of Mechanical Engineering of the University of Žilina. The task of proposed handling device will be to facilitate the work of laboratory staff, increase the safety of handling and shorten the preparation time of the measurement process at brake test stand. In addition, a more detailed description of the brake test stand at the Department of Transport and Handling Machines is included in the paper.
Analýza vlastností medených drôtov vyrobených pretlačovaním
(University of Žilina, 2024) Bílik, Jozef; Sobota, Róbert
The article focuses on the production of copper wires by extrusion and the evaluation of their mechanical properties. The article presents the results obtained on the basis of tensile tests and on the basis of hardness measurement. The tests were carried out on a semi-finished product with a circular cross-section and on manufactured wires with a rectangular cross-section. The wires produced were 9.5x4.5 mm, 10.5x1.65 mm and 5.75x1.35 mm. The impact of the transformation on the microstructure of the produced wire was also monitored.
Analýza vplyvu konštrukčného riešenia batériového packu na chladenie batérií počas prevádzky
(University of Žilina, 2023) Hlbočan, Peter; Csuka, Zoltán
The contribution is focused on the analysis of some possible approaches to the design of air cooling of the battery pack. The battery pack is equipped with a separate fan. As part of the analysis, the influence of the location of the fan in the pack and the direction of the cooling air flow on the cooling effect and the temperature field during operation were assessed. The result of the analysis is a specific recommendation for the location of the fan in the battery pack and the design of the air flow direction.
Aplikácia integrálnych transformácií na určenie vzťahu rozptylu morskej vlny od nadmorskej výšky hladiny mora
(University of Žilina, 2024) Malacká, Zuzana; Chupáč, Radoslav
The focus of this paper is the linear problem of gravity waves on the surface of a viscous incompressible fluid with a constant finite depth. This problem arises when the free surface is in a state of rest and there is a finite perturbation and a given normal pressure on it. We resolve the time evolution of the initial surface perturbation, or the classical linear Cauchy-Poisson problem, in the presence of a uniformly vorticous shear current beneath the surface. The solution is general, including the effects of gravity, surface tension, and constant finite depth. The main goal of this paper is to study such a problem, which appears to be important and interesting from a mathematical as well as a physical point of view. The problem is solved by using the Laplace and Henkel transformations, and we get an integral solution.
Aplikácia nedeštruktívnych metód kontroly na zvarové spoje vyrobené z plastu
(University of Žilina, 2024) Koňár, Radoslav; Grünermelová, Lucia
The article describes the possibilities of non-destructive testing of welds made of plastic materials. Both surface and volume methods of non-destructive testing can be used for plastic welds. Non-destructive testing of plastics has certain limitations. The limitations are related to the physical-mechanical properties of the material, as well as the geometry of the tested parts. The most common inspection of welds on plastic materials is a visual inspection, which is carried out to the extent of 100 %. For the inspection of plastic welds, it is also possible to use the penetration method and, with limitations, also ultrasonic and radiographic inspection.
Aplikácia solenoidu pri magnetickom tvárnení
(University of Žilina, 2024) Moravec, Ján
In the contribution, the theoretical part points out the known starting points for calculating the inductance of a long cylindrical coil. In the practical part, the method of application of magnetic forming in the production of tins in lead samples is presented. The results confirm the correctness of the hypothesis.
Aplikácie difúzie v strojárskej výrobe
(University of Žilina, 2023) Jaššo, Martin; Pastirčák, Richard
This thesis aims to explain the nature of the diffusion process and the importance of this process in the field of engineering production. The thesis contains information on the principles and mechanisms by which diffusion takes place, as well as on the environmental influences and factors that directly affect this process. The thesis concludes with a description of selected manufacturing and surface treatment processes used in mechanical engineering, the principal basis of which is diffusion.
Aplikačné možnosti HCCI technológie
(University of Žilina, 2023) Lavčák, Matúš; Puškár, Michal
This text describes the current state of the art of HCCI technology, which is based on combining the characteristics of a petrol and diesel engine. HCCI engines offer higher fuel efficiency and lower nitrogen oxide emissions. However, they also have disadvantages such as limited load range, control complexity and cold weather starting problems. The next section of the text discusses hybrid propulsion, which uses a combination of an internal combustion engine and an electric motor. It describes the different types of hybrid powertrains such as soft hybrids, plug-in hybrids and full hybrids. Explains their advantages and possible applications. A solution is then proposed where the HCCI engine would serve as a generator in a series hybrid vehicle with an electric motor. Such an arrangement allows optimization of energy use and reduction of emissions. Finally, the relevance of HCCI technology for improving the efficiency of fuel engines and hybrid vehicle design is evaluated.
Application of high-strength steel in the Wire Arc Additive Manufacturing (WAAM) process
(University of Žilina, 2024) Frátrik, Martin; Mičian, Miloš
The work deals with the application of high-strength structural steel in the process of wire arc additive manufacturing (WAAM). In this work, layers are welded by the cold wire TIG method. The aim of the work is to analyse the effect of process parameters and layering on the resulting geometry and mechanical properties of the experimental welds. The results showed that the mechanical properties of the welds are dependent on the direction of loading as well as on the welding thermal cycle.
Barkhausenov šum po dynamickom guľôčkovaní duplexnej ocele AlSi 318
(University of Žilina, 2024) Mičietová, Anna; Uríček, Juraj; Čilliková, Mária; Neslušan, Miroslav
This paper deals with surface integrity and the corresponding Barkhausen noise after shot peening of duplex steel AlSi 318 under variable shot-peening conditions such as number of passes and applied air pressure. Surface state is investigated from the point of view of surface roughness and surface plastic deformation. Barkhausen noise is decreasing along with increasing surface coverage as well as increasing air pressure. The duplex matrix is considered being stable with respect of volume fraction between austenite and ferrite and the whole Barkhausen noise signal originates from ferromagnetic ferrite. Progressively developed plastic deformation increases dislocation density in the surface as a result of surface bombardment by shots which in turn shift Barkhausen envelopes into higher magnetic fields.
Batérie druhej životnosti a systém správy batérií
(University of Žilina, 2023) Šuňal, Martin; Kopčan, Jaroslav; Benka, Denis; Kulhánek, Tomáš; Jandík, Jan
As electromobility continues to advance, there is a growing production of batteries that will eventually require recycling. One potential recycling approach involves repurposing worn yet still operational batteries in energy storage systems, providing them with a renewed functionality. Every battery assembly mandates a Battery Management System (BMS) to ensure proper and secure functionality. In the case of recycled cells, the BMS system becomes more intricate due to notable disparities in wear and, consequently, in parameters among the cells. Hence, active balancing of each cell within the assembly becomes imperative in such a setup. Furthermore, enhanced safety precautions are essential for such assemblies. The entire system must be scalable and adaptable to different numbers and configurations of battery cells from electric vehicles of various manufacturers.
Blechsschneiden unter Anwendung von Materiallwärmung
(University of Žilina, 2024) Moravec, Ján
In the paper, the theoretical part presents the issue of metal cutting. The experimental part deals with the investigation of the influence of temperature during the application of heating. the text of the paper is supplemented by a discussion and at the end of the paper there is an evaluation of the obtained results. The contribution appropriately and well complements a wide range of sheet metal cutting problems.
Corrosion behavior of the AlSi5Cu2Mg alloy with varying Zr addition
(University of Žilina, 2023) Širanec, Lukáš
The aim of this paper was to analyze the impact of varying zirconium additions (0.05; 0.10; 0.15 and 0.20 wt. % Zr) on corrosion behavior of the AlSi5Cu2Mg aluminum alloy. Potentiodynamic polarization corrosion tests in 3.5 % NaCl solution demonstrated that the addition of Zr improved the thermodynamic corrosion stability of the AlSi5Cu2Mg alloy by shifting the corrosion potential to more positive values for all as-cast samples. The addition of Zr to the as-cast alloys also improved corrosion kinetics by lowering the corrosion current density.
Determination of the dynamic load of an improved hatch cover of an open wagon during operating modes
(University of Žilina, 2023) Lovska, Alyona; Gerlici, Juraj; Dižo, Ján; Blatnický, Miroslav; Ishchuk, Vadym
The article presents the results of determining the dynamic load of the improved cover of an open wagon under operational conditions. The peculiarity of the manhole cover is that the canvas is formed by the upper and lower sheets, between which, there is an energy-absorbing material with viscous properties. The dynamic load of the cover when a load of 150 kg falls on it was studied. It was determined, that the use of energy-absorbing material contributes to the reduction of the cover load by 21 % compared to a typical original design. The main indicators of the dynamics of an open wagon equipped with improved manhole covers are calculated. The results of the calculations showed that the studied dynamic indicators are within the permissible limits. The conducted studies will contribute to the reduction of damage to manhole covers during operation and the cost of maintaining one wagons.
Disperzne spevnené materiály
(Žilinská univerzita v Žiline, 2023) Kantoríková, Elena
Dispersion reinforced systems are composites with a matrix reinforced with a dispersive discontinuous phase. They are mainly produced by powder metallurgy technologies. Dispersion-strengthened materials have a polycrystalline matrix, into which dispersed particles are introduced, most often of the type of oxides, carbides and nitrides. The essence of the strengthening effect of dispersoids is both direct and consists in inhibiting the movement of dislocations of the matrix, as well as indirect in that, during the formation of the system, dispersoids increase the density of dislocations and refine the grain and subgrain structure.
Dištančné vzdelávanie v technike
(Žilinská univerzita v Žiline, 2023) Stančeková, Dana
In connection with the current situation of distance education, a project was implemented within the operational program Interreg V-A Slovak Republic - Czech Republic 2014-2020 to develop knowledge outside the teaching process under the title "Support of distance methods in technical education", application code NFP304010AYI2. The project is aimed at creating distance learning materials for improving the quality of education of students and academic staff, by introducing technical webinars and online lectures for education in technical fields with a high proportion of examples of practical engineering production. An important activity of the project is the solution of CASE STUDIES - technical tasks from industrial practice, which lead to mutual transfer of experience between students and teachers and also experts from practice. The focus of the project thus leads to contact of students with important employers from the Moravian-Silesian and Žilina regions and thus helps their future employment on the labor market
Dodatočné spracovanie spekaných materiálov
(University of Žilina, 2023) Kantoríková, Elena
Powder metallurgy is a method of producing materials and products with required properties and required exact shapes. The development of new materials contributes to this. The general advantage of powder metallurgy is the possibility of producing parts of complex and precise shapes in large series and optimized production costs, resulting from lower energy requirements compared to casting and chip machining.