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Cold Spray coatings on high strength steels
Šesták, Stanislav ; Čupera, Jan (referee) ; Řehořek, Lukáš (advisor)
This bachelor’s thesis focuses on possible applications of the Cold Spray additive technology in context of high strength steels. The theoretical part of this work represents an extensive research on the topic of Cold Spray technology, showing connections between many of the mechanisms of this technology. This part also focuses specifically on high strength steels, their types, microstructures and properties. The experimental part of this work examines four samples of Cold Spray coatings on a high strength steel. After depositing these coatings, microstructure and microhardness analysis are provided.
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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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Repairs of component contact area using Cold Spray technology
Matiash, Dmytro ; Válka, Libor (referee) ; Řehořek, Lukáš (advisor)
The aim of this master’s thesis was to evaluate cold spray technologies as an alternative method of repairing contact surfaces of parts, especially made of high-alloy manganese steels, to choose a suitable system of materials and to analyze the properties and structure of the produced coating. The thesis presents the basic of the mechanism of cold spray deposition, the described influence of basic process parameters on the structure and properties of metal coatings. Performed analysis of chemical composition, structure, porosity, hardness and strength of AISI H13 steel coating on a high-alloy manganese steel substrate. The described dependence of the structure and properties of a given coating on the heat treatment regime.
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Current principles of Cold Spray coating, Cu coating characteristics
Barinka, Michal ; Jan, Vít (referee) ; Řehořek, Lukáš (advisor)
This bachelor thesis deals with the current principles of coating with the Cold Spray method. The research part deals with the principle of layer formation using the Cold Spray method. Furthermore, the current state of this technology on the market and its application in practice is summarized. The structure of deposited copper layer on two different substrates is evaluated in the experimental part.
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Microstructure and properties of YSZ thermal barier coatings deposited onto CoNiCrAlY bond coats remelted by electron beam
Slavíková, Barbora ; Jan, Vít (referee) ; Dlouhý, Ivo (advisor)
The master thesis is dealing with characterization of the structure and properties of the YSZ thermal barrier coating deposited by water hybrid plasma spray technology on the CoNiCrAlY bond coats modified by using electron beam and vacuum annealing. Deposition of the bond coats was performed via high velocity oxy-fuel technology and cold spray. In case of experimental evaluation, the microstructure and chemical composition of the ceramic top coat deposited with powder and suspension feedstock was analyzed. The same analysis procedure was used also for bond coats after electron beam remelting by using two sets of parameters. Furthermore, the changes in microstructure and chemical composition of the remelted and annealed bond coats was evaluated. Eventually, the micromechanical properties of the top coats and the bond coats were measured. The ceramic top coats deposited with powder feedstock exhibited the structure composed by splats, while the top coats deposited in form of suspension showed fine structure with columnar grains. The dendritic structure was observed on remelted bond coats. The annealing process had an influence on the structure in form of coarsened phases and the chemical composition was changed due to diffusion of the elements.
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Multimaterial structures preparation by using deposition methods
Novotná, Hana ; Čupera, Jan (referee) ; Řehořek, Lukáš (advisor)
This master’s thesis deals with origin, structure and mechanical properties of architectured material. The theoretical part deals with composits and theory of architectured materials. Further, the cold spray technology is described and it is used to create the network of grooves in the architectured material. In the experimantal part the influence of groof geometry and profil on the mechanical properties of the resulting architectured material is researched. Microstructure and hardness of the samples were also examined.
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Strucure and mechnical properties of cold sprayed Ti-6Al-4V layer
Sabela, Jakub ; Zelený, Martin (referee) ; Řehořek, Lukáš (advisor)
Diploma thesis deals in the first part with recent knowledge of cold spray, its mechanism and parameters of deposition, advanced coatings made by cold spray and their applications, knowledge of Ti-6Al-4V coatings and their heat treatment. Deposit of Ti- 6Al-4V powder was made by cold spray process. In experimental part, microstructure and mechanical properties of supplied and its heat treated material were observed and examined. Mechanical properties and microstructure remained unchanged by annealing at 600 °C as in the case of supplied material. Recrystallization occured in microstructure of and phases by annealing at 800 °C. Grains were emerged in microstructure and mechanical properties were decreased. Mechanical properties were improved by annealing at 900 °C due to quenching. Microstructure consists of and ’ phases. Mechanical properties were the worst for annealed material at 1000 °C because of coarsed grains. Material which was annealed at 800 °C, quenched and precipitation hardened had the best microstructure and mechanical properties.
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Effect of electron beam remeltin on binary mixtures deposited by the cold spray method
Novotný, David ; Řehořek, Lukáš (referee) ; Čupera, Jan (advisor)
This bachelor’s thesis deals with the effect of an electron beam remelting on binary mixtures of Fe-Al and Ni-Al, which were deposited by Cold spray. The Research study is focused on the basic principles of function and usage of the electron beam technology and the Cold spray method. Furthermore, binary systems of Fe-Al and Ni-Al are, along with their binary diagrams, also described in this part. In the Experimental part, the samples were remelted by an electron beam and consequently, the changes in microstucture were examined using electron and optical microscope.
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Process Gas Heating Systems in Cold Spraying
Babinský, Tomáš ; Ing. Tomas Denk, Glass Service Inc., Vsetin, CR (referee) ; Čížek, Jan (advisor)
The goal of this bachelor's thesis is to present ways of gas heating used in the cold spray technology. Primarily the work is focused on description of currently-used techniques of high-pressure gas heating in cold spray and introduction to commercial products. Part of the work is dedicated to the gas temperature influence on the coating process. Gas heating methods in various industrial applications are summarized in the final chapter for potential use in cold spray technology.
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