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The use of surface modifications in recent technical practice
Červinka, Martin ; Čelko, Ladislav (referee) ; Klakurková, Lenka (advisor)
Bachelor's thesis deals with problems of surface treatment materials and their basic division. Work is detail focused on technology of thermal spray coatings. This work summarizes the basic information about the technology thermal spray coatings, their features and an overview of methods for their production. The aim of the project is to create an overview of methods of surface modifications used in recent practice and their application in different branches of industry.
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Surface treatments of parts internal combustion engines
Toman, Josef ; Novotný, Pavel (referee) ; Maršálek, Ondřej (advisor)
This bachelor thesis is a professional research dedicated to the most frequently used surface treatments, applied to the stressed parts of internal combustion engines. The thesis also refers to surface treatments classification, benefits for the automotive industry and reasons for their development. Further it focuses on definitions of the technologies used, characteristics of processes and coatings, finishing operations after surface treatments and application of these treatments on the parts of internal combustion engines.
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Preparation and Characterization of Advanced Thermally-sprayed Coatings on Magnesium Alloys
Buchtík, Martin ; Hadzima, Branislav (referee) ; Fintová, Stanislava (referee) ; Ptáček, Petr (advisor)
The proposed dissertation thesis deals with the characterization of HVOF and APS-thermally sprayed coatings prepared on the AZ31 and AZ91 magnesium substrates. The theoretical part of the thesis describes in-detail Mg substrates used in the experimental part of the thesis. There are also characterized materials and coatings based on NiCrAlY and FeCrNiMoSiC metals, WC-CoCr cermets, and YSZ ceramic materials. At the end of the theoretical part, the literary research summarizing the characterization and analysis performed on thermally sprayed coatings on Mg alloys. Based on the theoretical knowledge, the characterization of Mg substrates and deposited coatings was performed in terms of the surface morphology, microstructure, and the chemical composition using the light microscopy (LM) and scanning electron microscopy with energy-dispersive spectroscopy (SEM+EDS). The phase composition of the coatings was analyzed using the X-ray diffraction (XRD). The diffractions corresponding to the sprayed coatings were compared with the feedstock powders, i.e. materials used for the spraying of the coatings. The characterization of the prepared coatings in terms of the mechanical and tribological properties was performed. The hardness and microhardness of the coatings as well as the coefficient of friction, and the wear rate were measured. The last chapter of the experimental part deals with the evaluation of the electrochemical corrosion properties by the potentiodynamic measurements in a 3.5% NaCl solution. In the case of exposed samples, the evaluation of the surface and coating/substrate interface was performed using LM and SEM with EDS. The mechanism of the corrosion attack and degradation was determined from the acquired knowledge and base on the results of the short-term measurements. Based on the measured results, it can be stated that the deposited coatings were successfully applied on the surface of both Mg alloys. All the coatings increase the surface hardness of the Mg alloys and significantly improve their tribological properties. However, except for FeCrNiMoSiC coatings, the corrosion properties of Mg alloys deteriorate due to the fact that the corrosion environment can pass through the coating to the less noble Mg substrate and the corrosion microcells are created.
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Thermal spray coatings of bioceramics
Kašpárková, Kristýna ; Mrňa, Libor (referee) ; Kubíček, Jaroslav (advisor)
Bachelor´s thesis is focused on thermal spraying bioceramics. Bioceramic is designed to replace damaged parts of the human body. Practical use is mainly in orthopedics, jaw and facial surgery. This category of materials includes hydroxyapatite, which is characterized by biocompatibility and the ability to form a strong bond between the bone and the implant. The experimental part of the thesis was spraying 40 - pieces of dental implants for the company LASAK s.r.o. Plasma spraying technology was used to apply the hydroxyapatite coating. The required coating thickness was 60 m. The implant was sprayed and cleaned before spraying. Spraying was carried out in the laboratory of plasma coatings dental and skeletal implants ÚST FSI VUT Brno. A dimensional control was performed after plasma spraying.
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Thermal spray by electric arc
Eliáš, Vojtěch ; Sigmund, Marian (referee) ; Kubíček, Jaroslav (advisor)
This thesis deals with the issue of thermal spraying by means of an electric arc. First of all, a theoretical part is processed using a literary study dealing with corrosion and thermal spraying technology. The experimental part contains a description of the technological procedure and evaluation of four thermally sprayed samples. Zinacor 850, consisting of 85% zinc and 15% aluminum, was used as a coating. The evaluation involves measurements of thickness, adhesion and roughness as well as the macro-structural analysis of the coating. Two samples showed unusually low adhesion, and all samples also had a large fluctuation of the measured thicknesses. This was also confirmed by the macro-structural analysis, which showed that the sample with low adhesion also had high porosity. These defects may have multiple causes, but the recommendation for further practice is to reduce the spraying distance from the base material.
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Optimalization of arc spraying parameters
Šildberger, Radek ; Filipenský, Jan (referee) ; Kubíček, Jaroslav (advisor)
The project elaborated as a part of engineering studies branch M2307: Engineering Technology, Specialization 02: Forming and Welding Technology deals with the optimization of arc spraying parameters for TAFA 9935 facility.The theoretical part presents the principle of arc spraying, the description of the technological process and the types of additional materials. The practical part proposes the diffrent possibilities of TAFA 9935 arc spraying facility and the suitable additional materials. Several samples with diffrent parameters of spraying were created in order to test and analyse the coating quality.
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surface finish for the container CASTOR
Tomek, Jan ; Kubíček, Jaroslav (referee) ; Žák, Ladislav (advisor)
Master’s thesis deals with the problems of the inner surface finish design for the CASTOR container. In the theoretical part are analyzed properties of metallic surfaces with their defects and various options of surface finishes for increased protection. The practical part of the thesis is focused on the design of appropriate technologies for specific requirements of the surface finish for the CASTOR container, creating test samples and their evaluation.
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Corrosion protection by means of plasma spraying coatings
Bartoněk, Daniel ; Řehořek, Lukáš (referee) ; Jan, Vít (advisor)
This thesis is focused on making study of technologies used for applying metal coatings as corrosion protection and commonly used materials. By means of metalographic analysis compare microstructures of coatings thermal spraying by zinc based alloys. The thesis is describing basics of corrosion, means of corrosion protection and methods used for making zinc coatings for corrosion protection. Experimental part is comparing coatings made by thermal plasma spraying and thermal spraying with use of electric current.
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Application of plasma arc in technical practice
Bednář, Šimon ; Kubíček, Jaroslav (referee) ; Daněk, Ladislav (advisor)
The first part of the thesis is devoted to research of technology which use plasma arc, as cutting, thermal spraying, surface heat treating and welding, the great emphasis is putted on the technology of welding. Second part of it is devoted to assessment of welds/joints which are made by TIG method and by PLASMA. At the welds/joints is assessed the total amount of heat input and the course of hardness in the cross section. At the welds/joints that were made by PLASMA was determined percent of dilution.
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