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Welding of deep-drawing steels with protective layer by laser-TIG hybrid technology
Brehovský, Patrik ; Sigmund, Marian (referee) ; Mrňa, Libor (advisor)
The diploma thesis focuses on laser welding of extra deep-drawn steel sheet according to the standard WSS-M1A365-A14 with a protective zinc surface layer. A 0,9 mm thick steel sheet with a zinc layer with coating weight 50 g · m^-2 is welded by a hybrid welding method Laser-TIG. The laser, as the primary energy source, is used for welding the material. The arc, provided by a non-melting tungsten electrode, is used for preheating the material for melting and evaporation of the zinc layer. Based on the initial experiments, the magnitude of the laser power with the welding speed was chosen as a constant parameter. The magnitude of the electric current, as the variable parameter, was set up to 0, 20, 30 and 40 ampers for welding the lap and the butt welds. Only one piece of the each weld type combination was made. The welds were afterwards tested to verify their quality and material properties. The first differences between laser welding with or without TIG preheating were visible during the experiment. The positive effects of the laser welding with preheating by TIG were confirmed. The material properties of the joints achieved better values and a influence of the welding defects on the quality of the joints was reduced. The Laser-TIG is a good choice for welding galvanized steel sheets in the mass production of automotive industry and it could be improved by more researches.
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Renovation of casting molds by laser cladding technology
Cicha, Tereza ; Kubíček, Jaroslav (referee) ; Mrňa, Libor (advisor)
The diploma thesis deals with study of laser cladding technology and possibilities of its use in renovation of casting molds made of hot-work tool steel. The theoretical part describes methods of laser cladding, testing methods and characteristics of the base material and its heat treatment. In the experimental part the test clads, and the metallographic samples were made. The samples were evaluated in terms of macrostructure and microstructure, especially clad geometry, dilution, and defects like pores and cracks. Microhardness was also measured. In conclusion a technical and economic evaluation was performed.
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Utilization of laser welding methods for fixation of electrotechnical sheet bundles
Adam, Tomáš ; Kubíček, Jaroslav (referee) ; Mrňa, Libor (advisor)
Thesis deals with individual technologies of packaging stator sheets and their use in practice. The greatest emphasis is placed on welding technologies, especially on the differences between the individual methods. The experimental part of the thesis is focused on finding suitable parameters for welding the stator package using a laser with a special wobling head. The samples were evaluated in terms of penetration depth, the number of defects, especially pores and grain coarsening.
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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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CNC Applications for Laser Cutting
Hruška, Daniel ; Žák, Ladislav (referee) ; Řiháček, Jan (advisor)
The following thesis deals with the theory of laser. In the first part, the thesis is focused on the issue of laser cutting (laser principle, cutting methods, laser division). Furthermore, the thesis is focused on basic theory of automation and NC/CNC control of machines. In the experimental part, the BUT logo was burned out with CO2 laser with the help of the company UnionOcel s. r. o.
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Use of laser machines in small companies
Gorgol, Daniel ; Trčka, Tomáš (referee) ; Kalivoda, Milan (advisor)
This bachelor thesis deals with laser technology. In the introduction thesis characterizes small and medium-sized companies. The next section describes the types of lasers and their possible applications in engineering industry. It also describes the possibilities of using materials for laser manufacturing as well as suitable semi finished products. It points to the use of this technology in established smaller companies. Finally, it proposes the application of laser machine to expand the machinery of smaller company.
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Use of laser machines in small and medium companies
Šuga, Samuel ; Jaroš, Aleš (referee) ; Kalivoda, Milan (advisor)
This thesis aims to critically evaluate the use of laser machines in the engineering industry, and with particular emphasis on small to medium-size companies focused on laser cutting. The usage of laser machines and their broad-spectrum application to various types of materials were evaluated. Using laser cutting technology, a component with optimal quality was successfully created. Thanks to this component, an experimental model was proposed, which describes how much of this product must be created for the company to stay on the market. The results suggest that using a fiber laser is the most suitable for small and medium-sized companies using laser cutting machines.
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CAD design of the Walther PPS M2 laser sight housing
Macků, Veronika ; Hejtmánek, Petr (referee) ; Vančura, Jan (advisor)
The aim of this thesis is to create a housing for a laser-sight for a Walther PPS M2 pistol with the aid of reverse engineering methods. The first part is a research about laser-sights. The second part contains contemplation about the problem, mainly the restrictions brought on by the design of the Walther pistol and of the energy source of laser-sight Streamlight TLR-6, as well as the chosen production method of the housing, which is 3D printing. The main part describes the acquirement of input data via scanning the body of the Walther pistol and the housing of TLR-6, the making of the CAD design of the housing, the printing of a prototype with a 3D printer and the consequent correction of the CAD model on the basis of analysis of the prototype.
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Laser-driven hard X-ray source for imaging applications
Lamač, Marcel ; Nejdl, Jaroslav (advisor) ; Kozák, Martin (referee)
With the advent of high-power lasers in recent decades, a unique source of hard X-ray radiation has become availible. This source of collimated, broadband, femtosecond, incoherent and hard X-ray radiation is produced when a focused laser with intensity above 10^18 W/cm^2 collides with a gas target. The strong electric field of the laser pulse ionizes the gas and interacts with the plasma generating a strong plasma wake wave. This space charge separation inside the target generates longitudal electric fields of the order of 100 GV/m. This resulting electrostatic wakefield accelerates the electrons to relativistic velocities and causes them to travel in oscillatory motion behind the laser pulse, producing hard and collimated X-ray radiation. This thesis is focused on a theoretical evaluation and an experimental design of this laser-plasma X-ray source. Furthermore, we consider the source's unique properties for novel imaging applications.
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Fantasy Genre in Czech Publishing Houses
Behenský, Petr ; Halada, Jan (advisor) ; Čeňková, Jana (referee)
The thesis refers to Czech publishing houses publishing fantasy, and to the condition of the fantasy genre in the environment of the Czech book market. This situation is examined through the analysis of the production of three publishing houses - Laser, Polaris, and Straky na vrbě. The aim is to discover how the market with fantasy literature developed during the last decade and to compare the success of the individual publishers and their strategies. The theoretical part deals with the role of the Publisher on the book market, mostly through his function as an entrepreneur and simultaneously as a bearer of culture. Next, it examines the current Czech book market. In the next part, the fantasy genre is defined, as well as its origins, development and the history of publishing fantasy in the Czech Republic. After that, the three analysed publishing houses are examined, with the focus on their publishing strategies. The practical part then compares the books published between the years 2009-2019 and their media response in the magazine Pevnost, online fanzine FantasyPlanet, online book database Databáze knih and the regular sales rankings of the Association of Czech Booksellers and Publishers (Svaz českých knihkupců a nakladatelů). First, each medium and the form of its response (review, user rating,...
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