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Modification of HVOF and cold spray deposited coatings via electron beam technology
Vacek, Petr ; Šiška, Filip (referee) ; Čížek, Jan (advisor)
The aim of this thesis was to modify microstructure and coating-substrate interface of CoNiCrAlY coatings deposited by HVOF and cold spray on Inconel 718 substrates. Electron beam remelting and annealing in a protective atmosphere were used to modify the coatings. Microstructure, chemical and phase composition were analyzed. The effect of beam current, transversal velocity and beam defocus on remelted depth was evaluated. As-sprayed microstructure and chemical composition of coatings were analyzed and compared with remelted samples. The effect of annealing of the as-sprayed and remelted samples was evaluated. Remelted layers exhibited dendritic structure. Chemical composition changed only after remelting of interface and part of a substrate. When only the coating was remelted, chemical composition remained the same. Phases coarsened after the annealing. Chemical composition changed after annealing due to the diffusion.
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Design of support structures for parts made of Inconel 718
Kuhajdik, Matej ; Hutař, Pavel (referee) ; Koutný, Daniel (advisor)
This master thesis deals by the design of support structures for the production of parts made of nickel superalloy IN718 using selective laser melting (SLM). The aim of this work is to design a support structure so that technological problems (excessive deformation of the part due to high residual stresses and insufficient heat dissipation) are eliminated and replace the use of massive volume support, which is inefficient in terms of design and production time, consumed material and postprocessing. Mechanical behaviour of residual stresses of built component, design points of selected support structures (perforated block with pins, BCCZ with perforated contour) and design recommendations were quantified by using thermo-mechanical simulations of production and series of experiments. The functional sample was tested by designing specific support structures for the turbine wheel with subsequent production. The support structure ensured safe, successful production without potential problems and met the requirement to minimize material consumption through effective large-scale perforation of the structure.
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Properties of Inconel alloy coating on austenitic steel made by cold-spray technology after electron beam remelting
Chlupová, Monika ; Řehořek, Lukáš (referee) ; Foret, Rudolf (advisor)
This diploma thesis is focused on description of the properties of a layer of Inconel 718 applied on austenitic steel AISI 304 by the Cold Spray and subsequently remelted by electron beam. The first part presents the Cold Spray with its properties, advantages and disadvantages, and also describes the principle of electron beam remelting and other possible uses of electron beam, for example welding, drilling, heat treatment etc. The second part describes the material and the methods used for the preparation and evaluation of the samples. There are evaluated the porosity, microstructure and microhardness of the layers applied by the Cold Spray and these properties are further compared with the properties of the same layers remelted by electron beam. In conclusion, the results of the porosity of the layers applied by the Cold Spray are discussed with the literature and the results of electron beam remelting are only partially described here, because it was not possible to find literature about this topic. There are also suggestions for further research of the properties of this layers, which is necessary to know before implementing this method of producing layers for commercial production.
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Development of SLM process parameters for thin-walled nickel superalloy components
Kafka, Richard ; Dočekalová, Kateřina (referee) ; Koutný, Daniel (advisor)
The diploma thesis deals with the development of process parameters of SLM technology for the material IN718. The main goal is an experimental development of a set of parameters for the production of thin-walled parts with regard to material density, surface roughness and tightness. The essence of the development of parameters is an experimental explanation of the influence of laser power and scanning speed on the morphology of single tracks, which are used for the production of a thin wall. Together with walls of larger widths and volume samples, it is possible to create an intersection of parameters by which is possible to create components formed by a combination of thin-walled and volume geometry. The performed research created a material set, where the parameters of thin walls are used for the area of contours of bulk samples. We managed to produce a wall with an average width of 0.15 mm and roughness of 6 m, which meets the requirement for the tightness. The meander scanning pattern achieved a relative material density of 99.92%, which is more than with the supplier's parameters. Based on the acquired knowledge, it was possible to apply a set of parameters to components combining both geometries.
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Use of Additive Technology for the Production Concept of Turbocharger Components
Robl, Jan ; Ňuksa, Petr (referee) ; Sedlák, Josef (advisor)
The thesis deals with possible use of additive technology in heat-resistant aplications. The rapid improvement of additive technology in recent years has brought more advanced materials such as nickel based superalloys, opening new oportunities for the use of this additive technology. First part of the thesis is dedicated to nickel based superalloys processing, precision casting and metal additive manufacturing. Other part analysed the results of mechanical properties and textures of the surface followed by a comprehensive assessment of DMLS technology. Part of the thesis is also the analysis of fracture surfaces on transmission and electron microscopy. Based on acquired nowledge, the conclusion is made about the possible use of DMLS in the future of heat-resistant applications.
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Comparison of laser welding and electron beam welding technology
Trost, Daniel ; Búda, Jaroslav (referee) ; Mrňa, Libor (advisor)
Thesis presents a comparison of technical evaluation of two welding technologies – dismountable connection of two materials, in this case superalloy Inconel 718. On the basis of the technological park of Honeywell Aerospace Olomouc s.r.o. coming into consideration still used the electron beam welding method which is compared in this work with the laser welding due to speed up the welding and a little heat input during the process of the welding.
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Inconel 718 machining for aerospace applications
Urbánek, Vojtěch ; Osička, Karel (referee) ; Polzer, Aleš (advisor)
Bachelor thesis is aimed at exploring the properties, usage and issues with milling of the Inconel 718 for aerospace applications. In the theoretical part a study of superalloys and their properties for successfull application in aircraft engines was conducted. Further the machinability classes, cutting materials and process of milling focusing on milling of the Inconel 718 are described. The experimental part deals with measuring and evaluation of cutting forces when milling the Inconel 718 with cemented carbide and ceramic cutting tools.
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Design of support structures for parts made of Inconel 718
Kuhajdik, Matej ; Hutař, Pavel (referee) ; Koutný, Daniel (advisor)
This master thesis deals by the design of support structures for the production of parts made of nickel superalloy IN718 using selective laser melting (SLM). The aim of this work is to design a support structure so that technological problems (excessive deformation of the part due to high residual stresses and insufficient heat dissipation) are eliminated and replace the use of massive volume support, which is inefficient in terms of design and production time, consumed material and postprocessing. Mechanical behaviour of residual stresses of built component, design points of selected support structures (perforated block with pins, BCCZ with perforated contour) and design recommendations were quantified by using thermo-mechanical simulations of production and series of experiments. The functional sample was tested by designing specific support structures for the turbine wheel with subsequent production. The support structure ensured safe, successful production without potential problems and met the requirement to minimize material consumption through effective large-scale perforation of the structure.
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Development of SLM process parameters for thin-walled nickel superalloy components
Kafka, Richard ; Dočekalová, Kateřina (referee) ; Koutný, Daniel (advisor)
The diploma thesis deals with the development of process parameters of SLM technology for the material IN718. The main goal is an experimental development of a set of parameters for the production of thin-walled parts with regard to material density, surface roughness and tightness. The essence of the development of parameters is an experimental explanation of the influence of laser power and scanning speed on the morphology of single tracks, which are used for the production of a thin wall. Together with walls of larger widths and volume samples, it is possible to create an intersection of parameters by which is possible to create components formed by a combination of thin-walled and volume geometry. The performed research created a material set, where the parameters of thin walls are used for the area of contours of bulk samples. We managed to produce a wall with an average width of 0.15 mm and roughness of 6 m, which meets the requirement for the tightness. The meander scanning pattern achieved a relative material density of 99.92%, which is more than with the supplier's parameters. Based on the acquired knowledge, it was possible to apply a set of parameters to components combining both geometries.
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Properties of Inconel alloy coating on austenitic steel made by cold-spray technology after electron beam remelting
Chlupová, Monika ; Řehořek, Lukáš (referee) ; Foret, Rudolf (advisor)
This diploma thesis is focused on description of the properties of a layer of Inconel 718 applied on austenitic steel AISI 304 by the Cold Spray and subsequently remelted by electron beam. The first part presents the Cold Spray with its properties, advantages and disadvantages, and also describes the principle of electron beam remelting and other possible uses of electron beam, for example welding, drilling, heat treatment etc. The second part describes the material and the methods used for the preparation and evaluation of the samples. There are evaluated the porosity, microstructure and microhardness of the layers applied by the Cold Spray and these properties are further compared with the properties of the same layers remelted by electron beam. In conclusion, the results of the porosity of the layers applied by the Cold Spray are discussed with the literature and the results of electron beam remelting are only partially described here, because it was not possible to find literature about this topic. There are also suggestions for further research of the properties of this layers, which is necessary to know before implementing this method of producing layers for commercial production.
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