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Výroba odlitků ze slitin hliníku odlévaných do kovových forem sklopným litím
Dočekal, Jan
This bachelor's thesis deals with the production of castings made of a non-ferrous metals, mainly of the alluminium alloy. The main emphasis is on the tilt casting method. The main focus of this work is introduction of the whole casting proces from task to casting of a specific product. Among another thing, are introduced a foundry technical equipments and a computer support. For a comparison are in the work included other metodes of casting alluminium alloys, mainly the gravity casting.
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Technologické metody svařování hliníku a jeho slitin
Pavlík, Zdeněk
The diploma thesis deals with the technology of welding aluminum alloy AW 5754 by a method of arc welding TIG and with covered electrode. Introduction contains information about aluminum alloys and their labeling according to ČSN EN 573-1,2. Additional attention is focused on evaluation of the weld quality according to ISO 10042 and subsequent evaluation of the defects according to ISO 65 20 to 1. In the experimental section was welded samples tested at first by non-destructive methods (visual, capillary, X-ray testing) and followed by a destructive measurement of the weld (evaluation of micro-hardness, macroscopic and microscopic tests, tearing issues). Furthermore, part of weldments was subjected to a laboratory corrosion test in an aggressive environment of a salt chamber and then evaluating of mechanical properties of welds in both methods.
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Weldability of hardenable aluminum alloys
Filip, Josef ; Slováček, Marek (referee) ; Kubíček, Jaroslav (advisor)
The thesis deals with the influence of MIG pulsed metal transfer welding on the mechanical properties of the aluminium curable alloy and on the presence of defects in the welded joint. The aluminium alloy EN AW 6082 T6 was chosen for the experiment, i.e. in the state after the artificial ageing. The experimental part first describes the selected base and filler material, the used welding equipment, the choice of welding parameters and then the preparation process of the test samples is described. There were made 6 sets of samples, each of them was welded with a different combination of welding parameters and pulsed welding mode. Subsequently, the work deals with several material destructive tests that were part of the experiment. Tensile tests, hardness measurements and microstructure tests were performed. The results of the tensile tests showed that in all cases the tensile strength was decreased by more than 30% compared to the base material and similar values were achieved. Thus, the theoretical assumption that soluble precipitates occur during the welding of hardened Al alloys, causing a decrease in the mechanical properties in the HAZ, was confirmed. It is evident in the results of hardness measurements, which for all samples reached the lowest values in the HAZ at the same place where fractures occurred in the tensile tests. The macroscopic examinations then showed the presence of micropores in all samples except the set num. 4, which did not develop porosity. In several cases, the presence of unbroken or oxide inclusions was also detected. The results are evaluated at the end of the thesis.
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Mechanical properties Al-alloy EN AW 7020 at increase temperatures
Slouka, Marek ; Kohout, Jan (referee) ; Věchet, Stanislav (advisor)
The master’s thesis deals with high strength aluminium alloys AlZn4Mg (EN AW 7020). This alloy is used for high strength, low density, a good corrosion resistant and a good weldability in protective atmospheres. At first this thesis is described to aluminium alloys, ways of manufacturing and history. Next this thesis mainly deals with wrought aluminium alloys, heat treatment this alloys and alloys Al-Zn-Mg. Tensile tests were made of alloys EN AW 7020 at room temperature and increased temperature. Next this alloy was made of fatigue test and metallographic analysis. The model was construct. This model describe to behaviour alloy at increased temperature and this model was compared with measure values. This thesis describe to behaviour of study alloy at room temperature and increased temperature.
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Manufacture of optical mirrors for high-frequency antenna
Muzikant, Dušan ; Bumbálek, Bohumil (referee) ; Sedlák, Josef (advisor)
This thesis deals with problems with manufacturing of high frequency elliptic and hyperbolic optic mirrors, which makes one of the most important functional parts of parabolic satellites made for biggest and highest placed international astronomical radio-telescope in the world - ALMA, which is built on Chajnantor plateau in Chille in South America. Individual chapters are designed in the flow of technological process of manufacturing, containing theoretical and practical analysis of the problems. Content of the thesis leads especially to description and clarification of individual causes of problems during manufacturing.
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Draft of design and manufacturing technology for the enduro footrests
Vrzal, Jan ; Sliwková, Petra (referee) ; Polzer, Aleš (advisor)
The diploma thesis is focused on draft of footrests for endure Honda Transalp XL700V of 2008. Attention is paid to the draft of the design of the footrest which is, which is designed for driving in light off-road. There is also described the issue if the choice of the material from aluminium alloy and the verification of the methods of the designed geometry using FEM and Rapid Prototyping. The experimental part deals with the design of appropriate tools and cutting conditions and with the creation of the NC program in ShopMill. There is enclosed the technical documentation and the NC program in the final part.
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Optimization of aluminium casting process using numerical simulation
Kolařík, Martin ; Lána, Ivo (referee) ; Krutiš, Vladimír (advisor)
The master’s thesis deals with the analysis of casting technology of the selected aluminium casting. It is a casting of a part of CNC milling machine and it is cast by gravity casting into a permanent mold. The defects which are the cause of a high percentage of nonconforming production were analyzed. Furthermore, the master’s thesis includes a complete analysis of filling and solidification of this casting in the ProCast simulation program. Numerical simulation results are verified and improved. Then the causes of problematic casting defects are proven on several calculated variants. Measures are proposed to minimize the tendency to produce castings with defects leading to nonconforming production.
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The effect of plastic strain of the reinforcement of aircraft panel made from aluminium alloy on the corrosion process
Valoušek, Tomáš ; Tulka, Jaromír (referee) ; Pacal, Bohumil (advisor)
This bachelor thesis is focused on study of corrosion of reinforcement panel of aircraft in environment of salt fog. The reinforcement material is aluminum alloy AlZnMgCu1,5 after solution annealing, release stress relieving and artificial aging, can be slighly deformed to compliance limit deviation. Material is not provided with any coating. The aim was to find out what is the effect of plastic deformation on the corrosion behavior of this alloy. In the experimental part of this thesis were studied the size and type of corrosion attack of samples with different plastic deformation. These values were furhter processed, evaluated and were drawn from them conclusions.
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Optimization of tool cutting geometry for high-speed machining of thin-walled parts
Barcuch, Jakub ; Humár, Anton (referee) ; Píška, Miroslav (advisor)
The theoretical part of the thesis deals with materials used in the aircraft industry with a focus on aluminium alloys. Then it describes high speed machining, its characteristics and its comparison with conventional machining. The following chapters describe strategies of machining thin-walled parts and a description of vibration that occurs during machining. The practical part deals with selection appropriate tool geometry, machining of thin-walled parts and evaluation of their deflection during machining.
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