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Optimalization of cutting process for machining of aluminium profile on CNC centre
Král, Ondřej ; Fiala, Zdeněk (referee) ; Jaroš, Aleš (advisor)
This master‘s thesis deals with the suggestion of suitable tools for milling aluminum alloys profiles for the construction of aperture fillings and their aplication to a CNC machining center for increasing the efficiency of the cutting process. The first part of the thesis is focused on the description of the company and the workplace of production of aluminum alloys constructions. The following pages contain description of standardized products, which are used to identify the test profile that is part of the experimental verification. Next part of this thesis is characteristic of aluminum alloys and tool materials suitable for their machining. Second part of this work contains an analysis of the current state, suggestion of new cutting tools and their application to the production proces. At the end of this thesis there is the technical-economic evaluation that deals with the time and economic savings of the applied design.
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Loss of strength during welding aluminous alloys AW 6060
Sklenář, Martin ; Vaněk, Mojmír (referee) ; Sigmund, Marian (advisor)
The aim of the bachelor thesis is to qualify the welding procedure according to the standard ČSN EN ISO 15614-2. At the beginning of the work is introduced a company with which was this thesis made. This is followed by an assessment of the issue of aluminum. Furthermore, the mechanical properties of aluminum are discussed. Follows by part about welding specially about aluminium welding. In the practical part the samples were welded and subsequently evaluated, then the design and qualification of the welding process was made. In conclusion, the possibilities and results that have been achieved are summarized.
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Age forming of aluminium alloys
Stanislav, Filip ; Petrásek, Miloslav (referee) ; Klement, Josef (advisor)
The diploma thesis is focused on the description and the verification of a relatively young creep age forming method. This method is based on a relaxation of stress and a creep of material, which occur by forming a part in the clamping tool during the artificial precipitation heat treatment at elevated temperature. After removing from the tool, the spring back and the residual stresses in the part are smaller compared to the conventional forming methods. This is mainly reflected in the increased fatigue resistance of the structure. The creep aging is only applicable to the precipitation heat treatable alloys. This thesis is focused on aluminium alloys, which are typical for the aerospace industry. The first part of the thesis describes principles of technology, its use in the aviation and material processes in the aluminium precipitation heat treatable alloys during the creep age forming. In the second part, there is a methodology of the verification of technology on samples made of the aluminium alloys ČSN EN AL-P 7075 and ČSN 424203 (approximate equivalent of ČSN EN AL-P 2024). Furthermore, a forming tool is designed, and experiments are performed according to the proposed methodology. At the end of the thesis, the experiments are evaluated and changes in the spring back of the samples are compared for three different methods of forming: the conventional cold clamping forming, the creep age forming and the creep age forming with an overaging.
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Use of laser-TIG hybrid technology for welding aluminium alloys
Drápela, Petr ; Šebestová, Hana (referee) ; Mrňa, Libor (advisor)
Different problems arise from choice of setting technological parameters during welding of alluminium alloys. Choice of welding method, welding speed and material influence mechanical properties of welds. During welding of alluminium alloys come difficulties due to oxidation of thin surface layer of material. One of ways how to overcome this obtacle is to use hybrid laser-TIG welding method. In this diploma thesis is described influence of welding processes on mechanical properties of two alluminium alloys(EN AW-5754 H22, EN AW-6082 T6) and change in their microstructure during welding.
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Transmission Electron Microscopy of Al-Mg Aluminium Alloys with Addition of Sc and Zr
Křivská, Barbora ; Šlapáková, Michaela (advisor) ; Málek, Přemysl (referee)
Abstract. The microstructure and its evolution during isochronal annealing of a twin roll cast Al-3.2Mg-0.19Sc-0.14Zr (wt.%) alloy was investigated by light optical microscopy and electron microscopy. Two procedures - equal channel an- gular pressing and annealing at 300 řC for 8 h were applied to enhance mechanical properties of the alloy. The annealing led to the precipitation of a fine dispersion of Al3(Sc,Zr) particles providing an increase of ∼20 HV in the Vickers microhard- ness. Equal channel angular pressing refined significantly the microstructure and raised the microhardness by about 30 HV. Applying of the 300 řC / 8 h both before and after equal channel angular pressing did not induce further strength- ening. However, the precipitation of the Al3(Sc,Zr) phase had a stabilizing effect when the material was exposed to the subsequent isochronal annealing. 1
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CNC pocket milling of aeronautical alloys
Wiecková, Kateřina ; Sedlák, Josef (referee) ; Ohnišťová, Petra (advisor)
The aim of the work is to generate and verify pocket milling technology in aviation alloy 7475-T7351 with respect to machine time, surface and machining productivity. First part of the work is theoretical analysis of cycles of milling of simple and complex pockets. Next part of the work is focused on the desing and optimization of strategy of milling of simple and complex pockets in CAM programs and its experimental verification.
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Influence of degassing parameters on quality of Al castings
Jeřábek, Petr ; Horenský, Jiří (referee) ; Vašťák, Patrik (advisor)
This master’s thesis is focused on optimalization of degassing parameters in the foundry plant and effect of these parameters on mechanical properties of Al-Si alloys. In practical part is used factorial experiment to research effect of degassing parameters on mechanical properties and dichte index. After optimalization the new process is validated by comparing with the previous one. This experiment was taken on AlSi7Mg0,6 alloy in foundry plant MESIT foundry, a.s.
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Robotic welding of hliníkových slitin
Pekárek, Mojmír ; Kočiš, Petr (referee) ; Vetiška, Jan (advisor)
This bachelor's thesis investigates robotic welding of aluminium alloys. It is divided into for parts, which are a summary of the findings of this problematic. The first part is focused on the robotics and the main distribution of industrial manipulators. The next part investigates about three possibilities of aluminium alloys welding at which two of them are focused on arch welding and the last one on the laser welding. In the third part is illustratively demonstrated the knowledge from previous parts on three various real cases to which is added also superstructure about process modification possibilities. At the end of the thesis is processed case study, which brings application of theoretic information in practice.
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Surface pre-treatment of structural aluminum alloys for bonded joints
Pikner, Jan ; Doskočil, Leoš (referee) ; Wasserbauer, Jaromír (advisor)
This thesis deals with pre-treatment of surface of aluminium alloys. The theoretical part focuses on the properties of aluminium and its alloys, on methods of surface treatment and the possibilities of quality assessment of pre-treated surface. The experimental part deals with finding of a proper method of pre-treatment. The quality of surface pre-treatment is assessed by observation by SEM with EDS and by single lap shear tests of adhesive joints. According to evaluated results, the optimalised methods are qualitatively and financially compared with the commercial method.
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Microstructure and mechanical properties of aluminium alloys prepared by severe plastic deformation
Bajer, Jan ; Cieslar, Miroslav (advisor) ; Král, Robert (referee)
New technologies of components assembling in car and aircraft industries and requests on improved mechanical and corrosion properties of metallic materials in the packing industry activate the utilization of highly innovative and unconventional manufacturing processes. There are only a limited number of processing, that retain the original material thickness and in an appropriate manner modify material properties. These are different types of annealing, severe plastic deformation methods or combination of both. In recent years constrained groove pressing (CGP) was devoloped with this method the grain size can be reduced from tens of micrometers to sub-micrometers. The present work is focused on a study of evolution of microstructure and mechanical properties of two alloys based on EN AW 3003 after CGP deformation and subsequent annealing.
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