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Dependence of the laser weld geometry on the bevel size
Man, Antonín ; Kubíček, Jaroslav (referee) ; Mrňa, Libor (advisor)
This work deals with laser welding technology. It explains in more detail advantages and disadvantages, applications and direction in which this relatively young technology develops. The main topic of this work is welding of martensitic stainless steel with carbon structural steel. Components of this type can be found, for example, in the power industry, specifically the stator part of a steam turbine. Part of this work is also an experiment that will explain the dependence of the geometric dimensions of the material to be welded on the quality of the weld. The welded test specimens were subsequently tested by both the non-destructive and destructive methods. It can be stated from the results, that the size of the bevel does not affect the quality of the weld, nor geometry.
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Arc welding of stainless steels for demanding working conditions
Matějíček, Josef ; Hála, Michal (referee) ; Kubíček, Jaroslav (advisor)
Bachelor thesis introduced deals with Arc welding of stainless steel. With welding technology, used by company DIAMO, the connected pipes, flanges and plates are for guiding the Sodium Sulphate solution, which is obtained as by-product in production of Uranium. Corrosive attack and weld cracking occurs in the short period of time due to the chemical reaction. Based on information about materials, used additional materials and welding technology used I have evaluated materials with susceptibility to the corrosion and the formation of hot cracks. Using tests and calculations I have examined the susceptibility of austenitic stainless steel to intergranular corrosion. Austenitic-ferritic stainless steel was also used as a theoretical solution for larger spectrum of materials. After calculations and evaluations of the trial tests I have conducted discussion and recommendations for use in practice.
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Macrosegregation and microsegregation in austenitic CrNi steels
Ostratický, Marek ; Čech, Jan (referee) ; Záděra, Antonín (advisor)
This diploma thesis deals with segregation cycles in austenitic CrNi steels. In first section deals with theory of macrosegregation and microsegregation cycles. The second part is focused on this cycles in experimental casting. Macrosegregation was measured by spectrometric analyser and by MAGMA simulation program. Microsegregation was measured by electron microscope. The aim of this diploma thesis is verify the influence of setting conditions on heterogenity chemical composition in austenitic CrNi steel. For experimental casting with a wall thickness of about 500 mm will be verified effect of the setting time, residence time between solid and liquid phases and others parameters for macrosegregation and microsegregation in selected elements.
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Manufacture and properties of high-alloyed Cr steels
Invald, David ; Haluza, Jakub (referee) ; Záděra, Antonín (advisor)
The bachelor thesis deals with the issue of properties, production, distribution, and use of high-alloyed chromium steels. One of the main part of the thesis is devoted to corrosion because corrosion resistence is important properties of high-alloyed chromium steel. The last part deals with high-alloy steels production and equipment for steel production.
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Effective milling of stainless steels using octagonal inserts
Kouřil, Petr ; Sedlák, Josef (referee) ; Zemčík, Oskar (advisor)
Thesis aims on efficient milling of stainless steels. Groups of these steels are characterized and their machinability is analyzed in theoretical part of this thesis. In the practical part of thesis were face milled stainless steels ČSN 17 240.4 a ČSN 17349.4. There are evaluated edge durability, roughness of surface, loading of total cutting force and effectiveness of test tools.
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Shoulder milling of stainless steels
Holeček, Václav ; Kalivoda, Milan (referee) ; Humár, Anton (advisor)
The bachelor thesis talks about sholder milling of stainless steel. The first part deals with the general thesis including shoulder milling with the of division milling tools. Further stainless steel is described including its machinability. The main part is analyses mills for shoulder milling made by world´s producers, which are finally eva-luated from differen points of view.
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Impregnation of stainless steels for the conditions of oversea sailing
Chára, Tomáš ; Kalina, Lukáš (referee) ; Zmrzlý, Martin (advisor)
This thesis deals with temporary corrosion protection of stainless steel for the conditions of oversea sailing. At first the theoretical part describes types of the stainless steels focusing on their corrosion resistance and negatively or positively impacts affect of their resistance. There is also a proposal of methods of the temporary corrosion protection and testing its effectiveness. The recherché are summarized knowledge in testing resistance of stainless steels to pitting corrosion. The task of the study was to test the effectiveness of three different preservatives and comparing the quality of their temporary corrosion protection compared with unprotected chemically passivated stainless steels.
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Stainless steels
Chára, Tomáš ; Kalina, Lukáš (referee) ; Zmrzlý, Martin (advisor)
This thesis deals with stainless steels. The theoretical part describes the mechanisms and types of corrosion. Then the thesis deals with the properties, distribution and manufacture of the stainless steels and a brief description of the XPS method used for the practical part. In the recherche section summarizes the ways of using the XPS method for determining the quality of the passive layer of stainless steels eaten in different environments. Practical task was to compare the quality of the passive layer of stainless steels resulting from natural and chemical passivation.
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Working of semi-finished product for laser welding
Černý, Jan ; Mrňa, Libor (referee) ; Kubíček, Jaroslav (advisor)
The thesis deals with the technology of laser welding and preparation of semi-finished products for laser welding for serial production. The theoretical part deals with the physical nature of the laser, different types of lasers, welding technology, preparation of welded surfaces, safety of work with lasers and basic division of corrosion resistant steels. The practical part deals with the assessment and evaluation of the proposed technologies of cutting blanks for laser welding. In the practical part, roughness, flatness and macrostructure tests were performed and evaluated.
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Metal Biocompatible Materials
Stejskal, Pavel ; Němec, Karel (referee) ; Molliková, Eva (advisor)
The bachelor’s thesis deals with metal biocompatible materials, their chemical composition, heat treatment, final mechanical properties and possibilities of application of these materials. Basic terms and separation of the biocompatible materials are explained in thesis introduction. Next there are outlined a historical side and main reasons of development of these materials.
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