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.

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.

The content of this thesis deals with the manufacturing of the prototyped series of low friction ring, proposing of the serial production and economical and technical evaluation. This thesis also solves the surfacing of low friction rings and testing. The thesis is devided into two main parts. First part deals with selection of material, tools and process of manufacturing low friction ring. Second part concerns surfacing and after testing. The thesis ends with economic and technical evaluation.

Aluminium toxicity is the main limiting factor in crop production on acid soils. The main symptom of aluminium toxicity is a rapid inhibition of root growth, but the mechanism of root growth cessation remains unclear. In this diploma thesis we deal with the question of whether phospholipases PLDα1 and PLDδ may play a role in the mechanism of aluminium toxicity. We compared the responses of plants lacking PLDα and PLDδ with WT plants. Growth analysis of roots was performed in hydroponic conditions. The most sensitive part of roots was transient zone in which cells were dying earlier. It was further found that pldα1 plants were less sensitive on aluminium toxicity because their roots showed less growth inhibition than WT. Pldδ plants did not differ from WT plants in their response to aluminum. During further analysis of the pldα1 reactions, it was found that the root cells were capable of cell expansion during aluminum toxicity, and the cellular malformations were formed on the roots. This phenomenon was associated with faster reorientation and even depolymerization of cortical microtubules in response to toxic aluminium in pldα plants compared to WT plants. The results indicated that PLDα1 molecule affects the stability of cortical microtubules. Microtubules were less stable and they depolymerized...

Tato práce se zabývá problematikou nárůstku. Jde o řešení konkrétního průmyslového problému. Pro daný odlitek ze slitiny hliníku a řezný nástroj ze slinutého karbidu je studován výskyt nárůstku pro různé řezné podmínky. Nejprve se práce zabýva rozborem tématiky nárůstku, mechanismy jeho vzniku a parametry, které mají na jeho výskyt a růst největší vliv. Dále je věnována pozornost studiu materiálu odlitku, jeho nové koncepce a původního řešení. Během inovačního procesu došlo k obměně použitého materiálu. Tato změna se na procesu řezání projevila vznikem významného nárůstku, který vede až k úplné destrukci nástroje. Byly provedeny zkoušky tvrdosti a metalografické výbrusy pro detailní popis a srovnání vlastností obou slitin hliníku. Výsledky zkoušek prokazují rozdíly v metalografické struktuře (velikosti dendritů, množství precipitátů) a tvrdosti daných materiálů. Experimentální řešení problému spočívalo v testech vrtání do odlitků ze zkoušených slitin hliníku. Pro jednotlivé vrtací zkoušky byla měněna hodnota posuvu a řezné rychlosti. Za pomoci dynamometru byla měřena posuvová síla, dále byl použit wattmetr k určení příkonu stoje a synchroní funkce CN, jejichž výstupem byla aktuální poloha vřetene a řezný moment. Na zákldě naměřených hodnot byla vypočtena měrná řezná síla pro konkrétní testované řezné podmínky.Mimoto po každém pokusu byly pořízeny fotografie nástroje s daným nárůstkem. Z výsledků vyplývá, že měrná řezná síla má tendenci výrazně klesat se zvyšující se hodnotou posuvu, oproti tomu zvyšující se řezná rychlost nemá tak výrazný účinek na její snižování. Co se týče naměřené tloušťky nárůstku, tak se zvyšující se řeznou rychlostí dochází k jejímu poklesu. V případě růstu posuvu, má nárůstek taktéž tendenci klesat, ale menší měrou oproti předešlému případu. V závěru práce je uvedeno rozmezí řezných rychlostí a posuvů vymezující optimalizovanou zónu pro vrtání dané součásti. Následuje nabídka dalších možných experimentů vážících se k tématu studie.

This thesis examines the influence of the degassing process on hydrogen contend and on the quality of part casted by high pressure casting technologies. The type of defects occurring in the casting is analyzed based on macrostructure and microstructure observations. For the overall assessment is used the statistical observation of the evolution trend of scrapping during the experiment. The results show that shortening of the degassing time may affect the incidence of porosity defect.

This master's thesis is focused on the modeling and tracks of thin-walled components. Used softwares are CATIA V5R20 from Dassault Systemes for Experimental Component Modeling and PowerMILL 2018 from Autodesk for Draw and NC Programming. The production efficiency between the precision casting and the workpiece of the cube blank based on the material utilization factor and machining time is compared in this work.

The thesis is focused on the surface treatment used for the preparation of aluminium alloys for the adhesive bonding. The theoretical part can be divided into three chapters. The first of them deals with aluminium alloys, the second one speaks about the adhesive bonding. The surface treatment itself, especially the conversion coating issues, is discussed in the last chapter. The experimental part is focused on the optimalization of a two-step titanium and zirconium based conversion coating technology. In the first part, the aluminium alloy is analysed by the glow discharge optical emission spectroscopy. The second part of the experiment deals with the first step of the technology, acidic deoxidation. The objective was to examine the influence of the exposure time on the morphology of the alloy surface and the shear strength of adhesive joints. In the last part of the experiment, the conversion coatings are prepared and characterised by the scanning electron microscopy and energy dispersive spectroscopy.

The thesis focuses on the corrosion research of AlCu4Mg1 aluminium alloys of square shape and sheet metal coated in 99.5% aluminium. The theoretical part deals with the characteristics of aluminium, the classification and naming of aluminium alloys and the impact of admixtures on aluminium alloys. In the following chapter a general introduction to metal corrosion, its differentiation according to the type of corrosion attack, mechanisms of corrosion, the impact of corrosive environment, according to the choice of anti-corrosion protection, etc. is given. The main part is devoted to the corrosion of aluminium with a special importance of the impact of admixtures on aluminium alloys, the types of corrosion attack, the impact of corrosive environment as well as of the anti-corrosion protection of aluminium alloys. The corrosion tests in controlled atmosphere are considered in the next chapter, while the last one deals with the evaluation methodology of the process of corrosion. At the beginning of the experimental part all the used samples and materials are introduced. The thesis continues then with an overview and a description of the methods used for experiments. The measurement procedure and the results of the experiments are presented in the following chapter that focuses on the metallographic analysis of the aluminium alloy samples before the experiment and after the corrosion attack. The main part of the chapter deals with the dependence of corrosion speed of the individual aluminium alloy samples on time after being exposed in the climate chamber and the salt fog chamber

This master's thesis deals with design and machining of the flange hub rear wheel of the formula by using CAD/CAM technology and CNC workshop programming. The introductory part provides theoretical description and characteristic of turning and milling technology. Further work describes aluminium alloys with focus on material which was used as a blank for machined workpiece. The practical part deals with design of flange in CAD software Autodesk Inventor, design of turning strategies in system ShopTurn and design of milling strategies in software PowerMILL. The final part of this thesis specifies realization of manufacturing on CNC lathe and CNC machining center in company BOSCH DIESEL s.r.o. in Jihlava. Last chapter is focused on techno-economic aspects of manufacturing.