National Repository of Grey Literature 215 records found  beginprevious148 - 157nextend  jump to record: Search took 0.01 seconds. 
Unconventional production technology of chains
Hostinský, Michal ; Mrňa, Libor (referee) ; Osička, Karel (advisor)
Unconventional technologies and their continual development brings along new possibilities in the manufacturing process. The submitted project is focused on solving problems in the procession of sheet metals in the manufacture of special parts of roller and conveyor chains. In the assessment of the technology of components, laser cutting was evaluated as the most optimal technology. With this goal, there was a public tender in terms of the purchase of a new machine designed for the manufacturing operations of the company of RETEZY Vamberk. This company ranks among the most major manufacturers of conveyor, roller and special chains in Europe.
Optimization of the laser weld of overlap seam for zink layered sheet metal
Plíšek, Roman ; Kubíček, Jaroslav (referee) ; Mrňa, Libor (advisor)
This diploma thesis deals with the experiment of welding galvanized sheets using fiber laser. The experiment is based on testing of welds lap joints with different gap between the welded parts. Theoretical part of this diploma thesis describes the principles and different types of lasers, laser welding technology, welding defects, galvanizing and inspection of welded joints. In the experimental part of the thesis welding tests and analysis of the results of the experiment have been realised and evaluated.
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.
Optimization of laser welding of carbide cutting plates on a support tube
Franko, Matej ; Daněk, Ladislav (referee) ; Mrňa, Libor (advisor)
My thesis is considering the options of manufacturing of the core drill. One of these options is technology of the laser welding, which was described in details in the theoretical part of this thesis. In applied part of this thesis there were experimentally manufactured two pieces of core drills by using Yb-YAG fibre laser technology. One core drill was used for testing of the welding parameters and in the next step, these parameters were applied in real working conditions and were evaluated in final. Result is written down in the final part of my thesis. The second core drill was welded using the best values measured in the fixture, which was especially designed for this purpose.
The use of thermal spraying Al layer for absorptive layer of solar absorbers
Urbanovský, Jan ; Kubíček, Jaroslav (referee) ; Mrňa, Libor (advisor)
The thesis engage in structure of solar collectors in theoretical part. Secondly, theory of thermal spraying coating and anodizing is subscribed. In practical part of thesis is proposition of producing a spectral selective surface suitable for solar absorbers. Finally the properties of the samples are checked by thermographic camera shots.
Optimization of laser fusion cutting of coated aluminum sheets
Pokorák, Milan ; Hála, Michal (referee) ; Mrňa, Libor (advisor)
The thesis primarily deals with the optimization of laser cutting center for coated aluminium sheet cutting and with the subsequent comparison of measured results and a sample made using waterjet cutting. The thesis is divided in two parts, the theoretical part followed by the practical one. The theoretical section is concerned with the unconventional technologies used, with their general analysis, design, history and utilization for industrial appliances. Main parts of this thesis deals with classification of particular cutting principles and their specific description. The theoretical part contains also classificaton of aluminium alloy, description of surface texture measurement and explanation of basics terms used for roughness measurement. The practical section is concerned with the particular task solution and with all knowledge used for optimization and evaluation of laser cutting. This part contains the measurement results, the measured material, the machines and devices used and also the technical and economical evaluation of this thesis content. The overall evaluation of the laser cutting optimization of specific component is mentioned in the experiment outcome evaluation article.
Laser micromachining
Láznička, Pavel ; Daněk, Ladislav (referee) ; Mrňa, Libor (advisor)
This thesis deals with lasers, their general theory and application. Then a theoretical part describes laser micromachining and engraving. Experimental part of thesis deals with several experiments performed by powered fibre laser which is not primarily intended for the field of micromachining. Experiments were mainly evaluated by several types of microscopes where the amount of removed material was appraised. By particular experiments removed material was in accordance with used working parameters of laser and a significant role plays machining material. It emerges from the experiments that for the field of laser micromachining and engraving shorter pulses are more suitable (minimal pulse duration was 1 ms in experiment) and it is connected even with a way of removing material. Applied powered laser can be used for micromachining in specific fields of production.
Study of the properties of laser welds aluminum alloy grade 5000
Černohous, Filip ; Kubíček, Jaroslav (referee) ; Mrňa, Libor (advisor)
In working to address the properties of laser welds of aluminum class 5000th These alloys are characterized by low strength and good corrosion resistance. Created a few sample welds on Yb-YAG optical laser, which is subjected to mechanical testing . Procedures are provided in the work of laser technology and welding, as well as general properties and defects in welds. Made welds was evaluated and listed the best welding parameters of the studied process parameters .
Study of cutting defects in flame cutting of limit thickness of carbon steel by fiber laser
Králík, Petr ; Hála, Michal (referee) ; Mrňa, Libor (advisor)
This thesis deals with research of cutting defects at laser cutting of 15 mm thick carbon steel by Bystronic fiber laser with emphasis on wide cutting gap, which causes enlargement of wide of cutting gap and deterioration of roughness of cutting edge and increase of creation fo heat. The introduction describes the main types of lasers used for cutting sheet of metal and compare their advantages and disadvantages. Also described is a cutting process and its parameters, and also the possible cutting defects. An experiment was conducted on steels S355MC and S235JR and cutting defects were analyzed in relation to the set of cutting parameters. Next part determines the extent of the recommended parameters that should be chosen for specific cutting conditions and is balanced recommendations regarding the choice of material to be cut, and technological adaptations parts. In the last part is measured roughness of a wide cutting gap, the width of the heat affected zone and micro-hardness of the material.
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.

National Repository of Grey Literature : 215 records found   beginprevious148 - 157nextend  jump to record:
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