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Study of quality cutting edge of aluminum and copper alloys for fusion cutting in depending on the process parameters during laser cutting using a fiber YbYAG laser
Pilarčík, Edmund ; Kaván, Martin (referee) ; Mrňa, Libor (advisor)
The diploma thesis discusses laser cutting of non-ferrous metals using fiber YbYag laser and evaluation of the roughness of cutting edge samples. To manufacture samples of aluminium Al 99,5, deoxidized copper Cu – DHP and brass CuZn37 were used combinations of process parameters according to Taguchi statistical method. Samples were subsequently evaluated, according to the ČSN EN ISO 9013 standard and sorted into roughness cathegories, and by technical and economical evaluation, the most economical process parameter combinations were found. Experimantal part is preceded by description of general methods of cutting, description of laser types, process parameters and their influence on the occurrence of the cutting edge defects and description of roughness measurement and standard ČSN EN ISO 9013.
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Comparison of properties parameters of laser solid state
Bazalová, Lucie ; Mrňa, Libor (referee) ; Kubíček, Jaroslav (advisor)
The bachelor thesis deals with the characteristics, properties, parameters and application areas of solid-state lasers. It provides the explanation of the principle of laser beam and the associated individual types of lasers. This is followed by a more detailed division of solid-state lasers and their individual applications. Among these applications, more space is devoted to laser welding, where the main objective is to design a laser welding facility for steel welding up to a thickness of 10 mm.
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Laser welding of the abrasive steel
Sklenář, Zdeněk ; Daněk, Ladislav (referee) ; Mrňa, Libor (advisor)
The project, prepared by the engineering study compares the welding abrasive steel HARDOX 400, fiber laser welding method, which will be compared with a MAG welding method and using different protective gases (argon and helium). In the theoretical part, i worked both welding technology's and the issue of high-strength steel. In the experimental part were performed and evaluated by destructive mechanical testing and bending test, the transverse tension test, test macrostructure and microstructure of welds. In conclusion the thesis deduced the final results of the experiment.
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Laser welding of steels
Křivan, Miloš ; Mrňa, Libor (referee) ; Kubíček, Jaroslav (advisor)
The project elaborated within the bachelor‘s degree field of B-STI Mechanical Engineering is focused on the problems of laser welding of steels. The theoretical part of this project deals with lasers, methods of laser welding, effects of welding parameters on weld quality and the weldability of steels. In the practical part sheets that were made of S355J2G3 and S355J2C+N steels were butt welded. The aim of the practical part was a determination of such welding parameters as the welded joints meeting the quality requirements according to ČSN EN ISO 13919-1 standard and the hardness requirement less than 380 HV10 according to ČSN EN ISO 15614-11 standard. The tests of the macrostructure of the welded joints were conducted and assessed and the hardness of the welded joints was measured.
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Surface hardening of steels by high power diode laser
Bazalová, Lucie ; Daněk, Ladislav (referee) ; Mrňa, Libor (advisor)
The master thesis deals with the technology of surface hardening of steels by high power diode laser. The thesis is an experiment of surface hardening of steel 12 050 on various parameters of speed movement of the laser head and used power. At first, the work deals with the possible technology of surface hardening, industrial lasers and possible methods for measuring hardness. It describes the material used and the evaluation of the macrostructure and microstructure of the samples and evaluates the achievement of hardness, depending on the distance from the surface. The results are used to assess the suitability of the parameters during quenching.
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Optimisation of welding lines switch over
Hanauer, Tomáš ; Mrňa, Libor (referee) ; Kubíček, Jaroslav (advisor)
Project worked out in the bachelor degree in 2303R002 deals with laser welding of rails on serial welding lines with focusing on reducing of the total production cost of one piece. The bachelor thesis proposes to optimize and coordinate the activities of all personnel involved in this process. This work is carried out in cooperation with Bosch Diesel s. r. o. in Jihlava.
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Welding of socket from C-Mn steel
Boček, Martin ; Mrňa, Libor (referee) ; Kubíček, Jaroslav (advisor)
Final thesis, elaborated within the master study in the field of Manufacturing technology, deals with analysis and solving of weld cracking problem in welds of anti-roll bar socket for passenger car. Sockets material is fine-grained low-alloy steel S420MC. For better understanding of the problem, a literary study has been elaborated, describing the issue. Next, an analysis of parts material and its weldability, has been conducted, according to ČSN EN 1011-2 standard. After an analysis of cracks and considering current conditions of sockets welding a series of experiments has been designed to evaluate impact of different process parameters on final weld quality. Experiments results have been used to compile a series of recommendations for adjustment of the welding process and to eliminate weld cracking. The results of the experiments were used as a basis for elaboration of WPS protocol.
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Weldig of the different type of steel by the Yb-YAG laser.
Kopecký, Lukáš ; Kubíček, Jaroslav (referee) ; Mrňa, Libor (advisor)
Diploma theses is focused on welding experiment of maraging steel by use Yb-YAG laser. Experimet is based on testing of combination steel 11321 and maraging steel. Domex420MC, Domex720MC a QSE380. In theoretical part there are described laser technology of welding, weld defect, maraging steel and inspection of welded joints. In experimental part there are porposed test and made mechanical test of weld as transverse tensile test, bend tests, Erichsen cupping test, Vickers hardness test and makroscopic and microscopic examination of welds. In conclusion there are analysis of the experiment results.
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Weldig of the different type of steel by the Yb-YAG laser
Chlád, Luboš ; Hála, Michal (referee) ; Mrňa, Libor (advisor)
The master's thesis presents an experiment of welding of high strength steel Docol 1200 M and of steel DC01 by the fiber Yb-YAG laser. The experiment is based on testing welds which were made during the experiments. The lasers, laser technologies of welding, steels of higher strength, tailored blanks technology and testing of welds are described in the theoretical part. The practical part contains description and evaluation of tests of welds – transverse tension test, Vickers hardness test, Erichsen cupping test and macrostructure and microstructure test. The final evaluation results of the experiment are presented in the conclusion of the master's thesis.
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Studying the effect of the gap on the properties of laser butt welds
Holub, Matyáš ; Kubíček, Jaroslav (referee) ; Mrňa, Libor (advisor)
This thesis studies the impact of gaps on the properties of laser butt weld performed. For experiment was chosen DC01 ordinary steel and stainless steel X5CrNi18-10 (1.4301) with different thicknesses. The welding parameters depending on the gap between the welded plates remain constant. In the experimental part of the samples were welded using the Yb:YAG laser and compared to the tensile test, macrostructure, microstructure and Vickers hardness. At the end of the thesis are drawn experimental results.
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