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Wear regimes of aluminium alloys
Slivka, Václav ; Zapletal, Tomáš (referee) ; Šperka, Petr (advisor)
This thesis deals with the research of the wear regimes of the selected aluminium alloy in the conditions of dry friction. The aim of this work is the evaluation of the measure of an abrasive and adhesive wear of this alloy. This evaluation is made from the experiments which are made on the base of the knowledge of the research study. The dependence of the wear on the sliding speed and load, the friction on the sliding speed and load and the dependence of the normalised pressure on the normalised speed, so called the map of wear, are given on the base of the results of the measure.
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Optimization of surface pretreatment of steel and aluminum alloy for subsequent application of powder paint
Běloch, Martin ; Březina, Matěj (referee) ; Wasserbauer, Jaromír (advisor)
This diploma thesis deals with various procedures of surface pretreatment of steel and aluminum alloy for subsequent application of powder coating substance. The work begins with an overview of the general characteristics of the materials used. The core part of the work is then a summary of the individual methods of pretreatment that can be used to modify the material surface. A special chapter is devoted to methodologies for the application of powder substances. Before separate application, the sample must first be carefully pretreated to ensure removal of organic compounds (e.g. oils from primary processing - grinding, cutting), or dust impurities to ensure the correct barrier effect. After dividing the individual methods of surface preparation, a powder paint system with a total thickness of approximately 50 µm is applied to the test material. Samples with different surface pretreatments will be compared both in terms of mechanical properties and in terms of electrochemical properties.
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Technology of CNC production of aluminium alloy part
Novotný, Michal ; Polzer, Aleš (referee) ; Píška, Miroslav (advisor)
The diploma thesis Technology of CNC production of aluminium alloy part is based on the particular specification of the company FP cz s.r.o. The core of the work lies in the proposal of production technology of the given part made from aluminium alloy which is machined by two universal CNC lathes with operating system FANUC. There is an introduction to the issue of characteristics and machinability of aluminium and its alloys because of coherence of the thesis. Practical part is focusing on the particular proposal of production technology which consists of the casting analysis, method of clamping on the chosen machines, choice of tools and verification of the production. There can be achieved effective production and significant time reduction with proposed technology.
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Technology of CNC production of aluminium alloys parts
Věrný, Luděk ; Humár, Anton (referee) ; Píška, Miroslav (advisor)
This diploma thesis is elaborated on the specific assignment of AB Komponenty Ltd. The core of this thesis features the technology of manufacturing of component BASE CROSSBAR of aluminium alloy EN AW 2017 on the vertical machining center. CNC control program for the suggested technology is developed in the CAM software PowerMill 2010th. To complete the work it also includes a brief introduction to the issues and analysis of aluminum, aluminum alloys and coatings. From the perspective of the practice is probably the most beneficial and interesting final technical economic evaluation of selected solution of the given problem. The suggested technology can be a significant saving in production costs.
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Technology of aluminum alloy part production
Kostka, Dominik ; Kalivoda, Milan (referee) ; Osička, Karel (advisor)
The subject of this thesis is to focus on the casting and machining of aluminium alloy parts. Aluminium alloy castings can be cast by all the technologies available today, but only metal mould casting is the most suitable for aluminium alloys due to the rapid cooling process. The machinability of an aluminium alloy casting can be highly productive but carries the problem of build-up on the tool. The build-up can be avoided by changing the technology, choosing a different cutting material, or cutting conditions. Machining an aluminium alloy casting is more productive and less costly due to the small machining charge and the use of a more powerful machine. When machining apart from a semi-finished round bar, we need to use more machines, more process operations, and this will increase the overall production time of the batch. From a technical and economic point of view, the production costs for a semi-finished product from a casting are one third lower than for a semi-finished product from a cross-section.
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Evaluation of Cyclic Damage in Aluminum and Magnesium Alloys Using Acoustic Emission Technique
Vlašic, František ; Samek,, Jiří (referee) ; Fiala, Jaroslav (referee) ; Pazdera, Luboš (referee) ; Mazal, Pavel (advisor)
The thesis deals with the application of nondestructive testing methods (acoustic emission, electron microscopy, X-ray diffraction topography) to description and identification of stages in the fatigue process in aluminium alloys. The main contribution of this dissertation thesis consists of the approach and evaluation methodology of cyclic damage in the materials. It dealt especially with the verification of measured data by using data obtained using other nondestructive methods. The experimental results show that the field of nondestructive testing materials can fundamentally uncover the process of fatigue damage and improve current knowledge in this area. Combination of used methods has become a powerful tool for the identification and monitoring of the whole fatigue degradation process of materials.
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Materials for atypical constructions of bicycle frames
Motl, Daniel ; Věchet, Stanislav (referee) ; Němec, Karel (advisor)
Bachelor’s thesis deals with materials for atypical bicycle frames. At first goes to history of generally bicycles. After gives definition what atypical bicycle is and includes four practical examples this type of bicycle which was real manufactured. Next step is about materials. Firstly about all types of materials uses in bicycles industry. Secondly the most suitable materials for atypical frames were choosen. In the end this materials were described in detail.
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Welding of aluminum alloys with using SKS welding equipment
Šaloun, Jan ; Slováček, Marek (referee) ; Sigmund, Marian (advisor)
This thesis focuses on robotic MIG welding of aluminum alloys using welding processes from SKS Welding. The main task was to fine-tune the welding process to produce a weldment composed of profiles made of EN AW-6061 T6 alloy with a complicated cross-section connected by two fillet welds. Due to the limited number of profiles reserved for debugging, the welding process behavior was first tested on filled and overlap joints of 3 and 5 mm thick sheets made of EN AW-5754 H22 alloy with similar weldability to the alloy of the profiles. Both alloys could be welded using Argon 4.6 shielding gas and AlMg5 filler wire with a diameter of 1.2 mm. Fine-tuned KF-Pulse DP welding processes of sheets were used to initially set the welding parameters for the profiles. Variables were then gradually adjusted until acceptable visual and internal quality verified by metallographic cuts at the desired locations was achieved. A major challenge was to achieve the necessary penetration in areas where there were ribs. This requirement was achieved through a combination of different welding speeds, current values, and wire feed rates. Pores were reduced using the special Dual Pulse function.
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Technology of aluminum alloy part production
Kostka, Dominik ; Kalivoda, Milan (referee) ; Osička, Karel (advisor)
The subject of this thesis is to focus on the casting and machining of aluminium alloy parts. Aluminium alloy castings can be cast by all the technologies available today, but only metal mould casting is the most suitable for aluminium alloys due to the rapid cooling process. The machinability of an aluminium alloy casting can be highly productive but carries the problem of build-up on the tool. The build-up can be avoided by changing the technology, choosing a different cutting material, or cutting conditions. Machining an aluminium alloy casting is more productive and less costly due to the small machining charge and the use of a more powerful machine. When machining apart from a semi-finished round bar, we need to use more machines, more process operations, and this will increase the overall production time of the batch. From a technical and economic point of view, the production costs for a semi-finished product from a casting are one third lower than for a semi-finished product from a cross-section.
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Optimization of Machining Technologies for Special Applications
Ohnišťová, Petra ; Maňková, Ildikó (referee) ; Neslušan, Miroslav (referee) ; Píška, Miroslav (advisor)
This thesis is focused on the optimization of the milling technologies for special applications with respect to the required fatigue properties of aircraft components. The theoretical part of the thesis describes in detail the key features of the high-speed and high-feed milling, surface integrity after milling and fatigue characteristics of the studied component. The key aim of the work is devoted to the analysis of the influence of the cutting conditions of the high-speed peripheral and high-feed face milling of the bottom wing panel from aluminium alloy 7475-T7351 on the surface integrity in relation to the final fatigue properties. Therefore, the part of the work is a study of metallographic structure of the material, measurement of the accompanying machining phenomenon and quantities, advanced analysis of the surface integrity (amplitude characteristics, S-N parameters), manufacturing of the highly accurate fatigue samples and fatigue testing. Furthermore, the development of sample damage during in situ tensile loading and the development of sample damage during cyclic in situ fatigue tensile loading is also studied. The achieved results and fractography of fracture surfaces show that the studied cutting conditions have a significant effect on the quality of machining and resistance to mechanical stress, but they are not a decisive factor in terms of the fatigue crack nucleation. The effect of the achieved topography for the studied cutting conditions is suppressed by the presence of large intermetallic inclusions (Al7Cu2Fe; Al-Cr-Fe-Cu-Si) with a size from 2 µm to 20 µm, being the origin on the fatigue crack nucleation.
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