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Design of miniature specimens for calibration of ductile fracture criteria
Salvet, Patrik ; Vobejda, Radek (referee) ; Šebek, František (advisor)
Numerické simulace se v posledních letech s rostoucí výpočetní kapacitou výrazně rozšiřují. Metoda konečných prvků má velký potenciál k tomu, aby částečně nahradila a doplnila experimenty, které jsou drahé, zdlouhavé a často obtížně proveditelné. Jedno z hlavních využití numerických simulací je predikce a simulace chování materiálu. Tato diplomová práce se zabývá kalibrací a porovnáním různých fenomenologických kritérií tvárného porušování závislých na triaxialitě napětí a třetím invariantu tenzoru deviátoru napětí, které lze implementovat do metody konečných prvků k predikci růstu trhliny. Tato kritéria tvárného porušení byla kalibrovaná pro slitinu hliníku 2024-T351 s využitím makroskopických vzorků. Kalibrace byla provedena v MATLABU aproximací kalibračních bodů kritériem tvárného porušování s využitím optimalizační metody hejna částic. Hookův zákon, nový nedávno publikovaný model plasticity a nesvázaný model tvárného porušování kalibrovaný pomocí makroskopických vzorků byly implementovány do Abaqusu/Explicit za účelem navrhnutí čtyř miniaturních vzorků pro již sestrojené zkušební tahové zařízení. Navržené miniaturní vzorky zachycují různé typy napjatosti v místě iniciace trhliny zahrnující jednoosou napjatost, smykovou napjatost a rovinnou deformaci. Kombinací experimentů a numerických simulací těchto vzorků lze provést kalibraci kritérií tvárného porušování za účelem stanovení vhodnosti miniaturních vzorků pro predikci iniciace a šíření tvárného lomu.
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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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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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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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Electron beam welding of parts made from aluminium alloy
Jirák, David ; Jakoubek, Jaroslav (referee) ; Daněk, Ladislav (advisor)
The topic of this thesis was ordered by Valeo Compressor Humpolec Itd (further referred to as Valeo). It deals with the electron welding of a component made of an aluminium alloy, a piston specifically, which is made for an automobile air-conditioning compressor. The aim of this thesis was to analyze and suggest a way of increasing porosity of the welded area. The data needed for the analysis and the present state of the welded area was provided by Valeo.
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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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Processing of Al-Sc aluminum alloy using SLM technology
Skulina, Daniel ; Náhlík, Luboš (referee) ; Koutný, Daniel (advisor)
Master's thesis deals with the experimental determination of process parameters reaching densities >99 % for scandium modified aluminium alloy (Scalmalloy®) processed by SLM. The alloy achieves higher mechanical properties than the AlSi10Mg aluminum alloy commonly used. The theoretical part deals mainly with the results of Scalmalloy® alloys. Experimental bodies, testing methodology and evaluation method were designed on the basis of the theoretical parts,. The practical part is divided into four main stages: experimental determination of process parameters, a description of the effect of the parameters used on the relative density achieved, examination of the influence of process parameters on surface quality and mechanical testing. The mechanical properties were determined for the best parameters.
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