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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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Surface hardening of cast iron by high power diode laser
Bezděk, Pavel ; Daněk, Ladislav (referee) ; Mrňa, Libor (advisor)
The Master’s thesis deals with the technology of surface hardening by laser. High power diode laser is used for this purpose. Surface hardening is performed on cast iron BS 1452-77, at different speeds laser head and laser power. In introduction, the theoretical part deals with possible ways of hardening focusing on the benefits of laser hardening. There are mentioned basic parts of laser, type industrial lasers and their application in industry. The final part is mentions the using of material and methods used to evaluate samples. The practical part describes the using devices and carries out evaluation macrostructure and microstructure and evaluation of hardness depending on the distance from the surface.
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Macro and microstructure of weld joints made of titanium alloy TiAl6V4 by electron beam
Prachař, Václav ; Havlík, Petr (referee) ; Foret, Rudolf (advisor)
The aim of this bachelor thesis is to evaluate macro and microstructures of weld joints made of titanium alloy Ti6Al4V by electron beam welding with different processing parameters of electron beam and evaluate the impact of this processing parameters to the structure of resultant weld joints. The theoretical part deals with titanium and its alloys, the titanium alloy Ti6Al4V and electron beam welding technology. In the experimental part, 11 weld joints are evaluated, their macro and microstructures and hardness profiles.
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Comparison of GMAW and Plasma Welding
Nejedlý, Tomáš ; Mrňa, Libor (referee) ; Daněk, Ladislav (advisor)
Developed thesis compares MAG welding and plasma welding, with the same input parameters. Based on the literature was reviewed weldability and welding of both methods. It was experimentally for both technologies specifically designed heat input, evaluation and macrostructure of the weld dilution, the dimensions of the heat affected zone and finally test the hardness in the transverse direction Vickers.
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Assessment of heterogeneous properties butt welds in laser welding and electron beam welding
Rozsypal, Oldřich ; Kubíček, Jaroslav (referee) ; Mrňa, Libor (advisor)
The project was developed within the engineering degree in engineering technology, and is focused in welding together of two different materials. Welds will be done on a high strength steel Domex 420 MC and deep drawing steel DC01 using laser welding, and will be compared with the method of electron beam welding. Part of this project is a scientific research describing the basic physical principles of both methods, different types of lasers, welding material properties and inspection of welds. In the experimental part was carried tensile test, macroscopic and microscopic examination. Finally, work is to evaluate the individual tests.
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Macro and microstructure of weld joints made of titanium alloy TiAl6V4 by electron beam
Prachař, Václav ; Havlík, Petr (referee) ; Foret, Rudolf (advisor)
The aim of this bachelor thesis is to evaluate macro and microstructures of weld joints made of titanium alloy Ti6Al4V by electron beam welding with different processing parameters of electron beam and evaluate the impact of this processing parameters to the structure of resultant weld joints. The theoretical part deals with titanium and its alloys, the titanium alloy Ti6Al4V and electron beam welding technology. In the experimental part, 11 weld joints are evaluated, their macro and microstructures and hardness profiles.
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Theoretical problems of Spanish lexicography
Johnová, Barbara ; Čermák, Petr (advisor) ; Zavadil, Bohumil (referee)
The master's thesis Theoretical Problems of Spanish Lexicography introduces issues associated with creating general monolingual dictionaries. The thesis has two main objectives. Firstly, it aims to summarise the most frequent lexicographic issues and attempt to find their suitable solutions in practice through an analysis of significant research studies dealing with this subject. The issues have been divided into two groups depending on whether they regard the macrostructure (collection of dictionary entries) or microstructure (collection of headword information). As for the macrostructure, one of the main issues is posed by determining the criteria for the selection of dictionary entries. Modern descriptive lexicography considers lexical unit usage frequency to be the main criterion. The macrostructure of general monolingual dictionaries should generally not include proper nouns while productive affixes and affixoids, phraseological units with a high degree of idiomaticity, abbreviations and frequently used neologisms should be included. The thesis also explores the issue of distinguishing between cases of homonymy and polysemy and its impact on lexicographic practice. The chapter on microstructure focuses primarily on the issues of constructing lexicographic definitions with user...
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Surface hardening of cast iron by high power diode laser
Bezděk, Pavel ; Daněk, Ladislav (referee) ; Mrňa, Libor (advisor)
The Master’s thesis deals with the technology of surface hardening by laser. High power diode laser is used for this purpose. Surface hardening is performed on cast iron BS 1452-77, at different speeds laser head and laser power. In introduction, the theoretical part deals with possible ways of hardening focusing on the benefits of laser hardening. There are mentioned basic parts of laser, type industrial lasers and their application in industry. The final part is mentions the using of material and methods used to evaluate samples. The practical part describes the using devices and carries out evaluation macrostructure and microstructure and evaluation of hardness depending on the distance from the surface.
|
|
|
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.
|
|
|
Comparison of GMAW and Plasma Welding
Nejedlý, Tomáš ; Mrňa, Libor (referee) ; Daněk, Ladislav (advisor)
Developed thesis compares MAG welding and plasma welding, with the same input parameters. Based on the literature was reviewed weldability and welding of both methods. It was experimentally for both technologies specifically designed heat input, evaluation and macrostructure of the weld dilution, the dimensions of the heat affected zone and finally test the hardness in the transverse direction Vickers.
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