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Tools for threading and their use
Veselý, Václav ; Polzer, Aleš (referee) ; Sliwková, Petra (advisor)
The bachelor’s thesis Tools for threading and their use deals with issues connected to tools, the materials used and their usage in the field of mechanical engineering. Individual parts of the thesis cover types of tools for threading, methods of threading and materials suitable for tap making. Further, the range of monolithic milling taps in the producers’ supply is also analysed.
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Influence of pyrrolidone derivates on alkyd and polyurethane coatings.
Klímová, Edita ; Molliková, Eva (referee) ; Tulka, Jaromír (advisor)
The aim of this thesis was to append data on chemical resistance of coatings made of paints based on alkyd and polyurethane resins. In the theoretical part, relevant information on coatings, preparation of their systems, theory of solubilization and properties of solvents were collected and organized. Three N-derivates of pyrrolidone were chosen for the practical part. Their influence on particular alkyd and polyurethane coatings was studied with emphasis on time course of coatings degradation.
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Surface coatings of medium and high entropy alloy prepared by the cold-spray method
Vražina, Tomáš ; Adam, Ondřej (referee) ; Moravčík, Igor (advisor)
This bachelor thesis investigated coating of the CoCrNi (Medium entropy) alloy deposed onto austenitic steel substrate. The main objectives were characterization and analysis of sprayed deposition before and after heat treatment. The thesis was divided into 2 main parts. The theoretical part provided general information about alloy manufacturing, properties, and the method of its consolidation. The experimental part provided electron microscopy analysis including, an EDS, a porosity analysis and microhardness testing. Its results were then discussed on the base of the information gathered in the theoretical part. The results showed that the deposed layer was stable and there was no sign of material decohesion. The coating showed low porosity which was later successfully lowered by heat treatment. EDS proved that the coating was not entirely homogenous. The conclusion summarized the results achieved in the practical part.
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Modification of coating-substrate interface character of thermally sprayed coatings using electron beam technology
Mareš, Jiří ; Moravčík, Igor (referee) ; Čížek, Jan (advisor)
Tato práce je zaměřena na modifikaci charakteru rozhraní substrát-nástřik NiCrAlY povlaků nanesených pomocí technologie vodou stabilizované plazmy na substráty z oceli S235JRC+C. Přetavení žárové vrstvy elektronovým paprskem bylo zvoleno jako technologie pro modifikaci a dvě různé modifikace byly zkoumány. V práci byl proveden pokus o stanovení vlivu modifikací na adhezní vlastnosti nástřiku. Dále jsou v práci prezentovány analýzy mikrostruktury, fázového a chemického složení a mikrotvrdosti ve stavu před a po modifikaci. Během studie bylo zjištěno, že dochází ke změnám fázového složení jak během depozice, tak během modifikace elektronovým paprskem. Modifikace elektronovým paprskem způsobila roztavení oxidů původní mikrostruktury nástřiku, které následně rekrystalizovaly na povrchu modifikované vrstvy. Dalším získaným poznatkem bylo, že dochází ke snížení mikrotvrdosti po modifikaci, což bylo způsobeno odstraněním oxidů z mikrostruktury a promícháním materiálu substrátu a původního nástřiku. Adheze nástřiků v as sprayed stavu byla kvantifikována. V případě nástřiků modifikovaných elektronovým paprskem přesná kvantifikace nebyla možná, z důvodu předčasného porušení na rozhraní nástřik-adhezivní pojivo během adhezních testů.
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The technology of hot-dip galvanizing
Pometlo, Stanislav ; Osička, Karel (referee) ; Mouralová, Kateřina (advisor)
This thesis deals with the technology of hot-dip galvanizing. At the beginning of this work views into the history of hot-dip galvanizing and analysis of known technologies about applying of melted zinc into the surface of material. It further describes modification for surface before application of zinc´s coating. In the next part of the work are summarized the most common corrosions of hot-dip galvanized material. The work follows up the difficultness of operation for hot-dip galvanizing device. At the end of work describes cooperation with Alka Holding s. r. o.
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Progress in technology of mold milling with coated profile tools
Doležel, Ondřej ; Bumbálek, Bohumil (referee) ; Píška, Miroslav (advisor)
This diploma thesis is involved in possible development of different types of milling molds coated with modern plows. The first part is devoted to an analysis of contemporary trends in forms production technology. The analysis includes the different types of machines and tools for making various kinds of molds and dies. Another part deals with design of dies for sheet metal shears. The thesis continues by design of the production procedure after heat treatment and finishing die by miling. For milling of die are designed miling tools, the NC program and the possible development of manufacturing the die using a new machining center and the possibility of production optimization. The penultimate point of the thesis is technical and economical evaluation of the direction of development and comparison of positives and negatoves of each method. At the final evaluation is all summed up.
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Characterization of suspension plasma sprayed coatings deposited using different organic carriers
Dukovský, Daniel ; Toma, Filofteia-Laura (referee) ; Čížek, Jan (advisor)
Cílem této bakalářské práce bylo charakterizovat a porovnat povlaky nanesené plazmovým žárovým nanášením ze suspenze s použitím různých organických nosičů. Teoretická část obsahuje stručný popis běžně používaných metod žárového nanášení a blíže se věnuje technologii hybridního vodou stabilizovaného plazmatu (hořák s touto technologií byl využit pro nanesení povlaků v tomto výzkumu). Druhá polovina teoretické části se zabývá věcným popisem povlaků a metodami nanášení prášku o velikosti částic v řádu nanometrů, kde hraje důležitou roli právě použití suspenze. Experimentální část je zaměřena na vliv použitého solventu v suspenzi na charakteristiky výsledného povlaku. V závěrečné části jsou prezentována a diskutována naměřená data a vyhodnoceny výsledky.
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Coated cemented carbides
Foltýn, Michal ; Sedlák, Josef (referee) ; Humár, Anton (advisor)
This bachelor’s thesis is focused on coated cemented carbides, methods for coatings and properties of coatings. In the first part of this thesis there is mentioned basic subdivision of tool’s materials, including description of properties and possibilities of their use. Another part of this thesis is focused on the coating deposition methods. As each method there is noticed the description, advantages and disadvantages. In next part there are described processes which precede own deposition process and their influence on properties of coatings. In this thesis are also described properties of coatings and methods for their testing. The last part of thesis is focused on the offer of certain producers of coated cemented carbides. Several materials are chosen from each producer and there are mentioned descriptions of their properties, structure of coatings and possibilities of using.
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Materials Used for Cutting Tools for Metal Machining
Tomek, Lukáš ; Fiala, Zdeněk (referee) ; Kalivoda, Milan (advisor)
This thesis deals with cutting materials used for the production of inserts and tools for ma-chining. The aim of this thesis is to describe the various materials used in machining, their basic characteristics, composition and production. The work also includes a description of profiles of leading world producers of cutting tools. On the example of the designed shaft is made application of turning tools needed for its machining and short description of its production with a graphic demonstration. The final part is devoted to the evaluation of the turning in terms of used resources depending on the cost,productiontime and subsequent recycling of end-of-life instruments.
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