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Influence of alloying elements on the solubility of titanium in magnesium alloys
Matocha, Martin ; Buchtík, Martin (referee) ; Březina, Matěj (advisor)
This bachelor's thesis examines the influence of alloying elements on the solubility of titanium in magnesium alloys. In the theoretical part, a literature review was conducted on the topics of the creation, composition, processing, and brief analysis possibilities of magnesium alloys, with an emphasis on the potential for alloying magnesium alloys with titanium. The experimental part focused on the preparation of systems with various compositions to achieve the integration of titanium into the magnesium alloy. After preparation of the samples of the given systems, their analysis was performed using SEM/EDS and XRD. Based on the ongoing results of the samples analysis, efforts were made to optimize the holding time of the samples of the given system at a temperature of 905°C. It was found that during the stabilization of the modification of titanium, it is possible to achieve mixing of titanium, zinc, and magnesium. The condition for the formation of the modification of titanium is the highest possible temperature allowed by the system. However, the temperature must exceed at least 881°C. The stability of the modification of titanium is also supported by the absence of alloying elements that promote the stability of the modification of titanium. The mixture of elements in the aforementioned system has not yet been described in the scientific literature.
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Improving the quality of automobile wheel discs cast by the low-pressure casting method
Bělota, Martin ; Krutiš, Vladimír (referee) ; Kaňa, Václav (advisor)
The thesis deals with the identification of defects occurring in cast automotive wheels. The thesis also includes the design and experimental verification of measures that lead to an increase in the quality of production. The first chapter of the theoretical part deals with the occurrence of gases in aluminium alloys, especially hydrogen, its sources, solubility in aluminium alloys and the formation of gas cavities in castings. The second chapter describes ways of degassing the melt by vacuuming and bubbling with inert and active gases. The third chapter deals with controlled melt gasification, the purpose of melt gassing and methods of controlled gassing. The fourth chapter is devoted to the defects that occur in automotive wheels produced by lowpressure die casting technology. The fifth chapter describes the aluminum alloy AlSi7Mg0.3, which is used for the manufacture of cast wheels. It also describes the heat treatment of cast wheels. The sixth chapter deals with the practical part of the thesis, which includes the identification of defects using microscopic and radiographic methods. The next part describes the design and execution of an experiment in which Probat-Fluss MIKRO 100 was selected to improve the quality of production based on the results of defect identification. At the end of the practical part, the conducted experiment is evaluated, which also served to verify the effectiveness of Probat-Fluss MIKRO 100.
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Comparison of riveting and welding of motorcycle trunks
Pirmajer, Richard ; Slaný, Martin (referee) ; Kubíček, Jaroslav (advisor)
The work is focused on the comparison of riveting and welding technology for motorcycle trunks. The basic material is EN AW 5754 alloy with a thickness of 1.5 mm. The trunks made of this material were provided by SW-MOTECH. In the theoretical part, research was carried out on aluminium itself, its properties, types of heat treatment and weldability options. Furthermore, the CMT welding method and the piercing riveting method, which were used in the production of the trunks, were described. In the practical part, samples from both trunks, welded by CMT method and riveted by piercing rivets, were examined. Furthermore, the specimens were examined for the size of the heat-affected zone, the depth of penetration, the presence of defects, and the quality of the joint, respectively. At the end, the methods were economically evaluated.
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Residential building
Šeps, Daniel ; Bartlová, Jana (referee) ; Vajkay, František (advisor)
The subject of the bachelor thesis is the design of a new building of a detached apartment building in Nová Paka in the form of project documentation for construction. The buiding is designed brick with reinforced concrete ceilings. Perimeter walls on the 1st – 3rd floor is designed ceramic brick blocks th. 300 mm with contact thermal insulation system ETICS th. 200mm, which will be equipped with silicone plaster 1,5mm. Perimeter walls on the underground floor is designed permanent shuttering DITTON 30 th. 300mm, filled with concrete C20/25 XC1 and by steel B500B insulated with extruded polystyrene XPS th. 160mm. Internal load-bearing masonry wall is designed with acoustic ceramic brick blocks th. 250 mm. Partitions are designed from acoustic partition walls. On the ceilings is a hardwood flooring because of excellent acoustic characteristics. The roof is designed as a flat green roof with extensive vegetation and with thermal isolation of minera wool and with waterproofing layer made of bituminous modified SBS strips laid in two layers. Balcony railing is designed aluminous with safety glass paneling.
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Roof structure of construction for social purposes
Bašista, Ján ; Melcher, Jindřich (referee) ; Karmazínová, Marcela (advisor)
The work treats the static recalculation of an existing roof structure of a construction for social purposes and proposes two variants of the design of a new roof structure. The construction has a rectangular ground plan of 30 m x 47 m and the roof structure is placed on the load bearing circumference concrete walls. Except for the load constituted by the function of the construction and by the climatic area, an extra load of 2 tons suspended at any place of the structure is considered because of the special requirement of working and technological equipment. The variant no. 1 is designed from the steel S355. The variant no. 2 is designed as a combination of the wood GL24h and the aluminium EN-AW 5083. Both of the variants have 11 transverse load bearing girders. The purlins are perpendicular to the girders and are placed on them. Stiffness is secured by roof stiffeners.
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Reasons for pin holes formation in ductile iron castings
Opačitý, Radim ; Palán, Petr (referee) ; Šenberger, Jaroslav (advisor)
The aim of this thesis was to analyze the formation of defects in a given casting of ductile cast iron EN - GJS - 600-3 cast in sand molds bentonite, which is formed jolting with coining and then find a solution to remedy these defects. To resolve this issue, the influence of the composition of the sand mixture, the effect of metal flow in a cavity forms and the influence of deoxidation of metal in the presence of defects. Obtained results showed the importance of the influence Reoxidation metal cavity mold. Specifically, in this case succeeded in reducing the incidence of PINHOLES. Removal of PINHOLES to achieve deoxidation aluminum melt. This has reduced the production of nonconforming castings under 3% from the original 6.5%.
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Inspection of welded joints of loading ramps
Ertl, Roman ; Mrňa, Libor (referee) ; Kubíček, Jaroslav (advisor)
This master's thesis is focused on problem of welding of loading ramps and inspection of their welded joints. The aim of this thesis is to inspect the welds of loading ramps with regarding to the appearance of defects. The literature review of the research issues of the MIG welding technology and welding of aluminium and its alloys is described in this thesis. There is also described destructive and non-destructive inspection of welds that can be applied to inspection of loading ramps. Theoretical description is followed by an experimental part of the thesis. Experimental part is focused on the three destructive tests (the tensile, the macroscopic and the hardness test) of samples of loading ramps, which are made of EN AW-6005A T6.
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Options for increasing the efficiency of small motors.
Kusý, Karel ; Janda, Marcel (referee) ; Hájek, Vítězslav (advisor)
This bachelor thesis concerns itself with the possibilities of achieving higher efficiency of small asynchronous motors and their manufacturing costs. The following chapters describe the design, function and principles of speed regulation of the asynchronous motor. Next, losses that occur during motor operation and ways of reducing them, are described. The last chapter of the thesis addreses factors that influence the manufacturing costs of the asynchornous motor and evaluates the material costs of one modified motor.
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Machining of aluminum alloys
Pavliš, Jan ; Kalivoda, Milan (referee) ; Osička, Karel (advisor)
Bachelor thesis is focused on manufacturing of component YZ-RIGEL in Frentech Aerospace s.r.o. factory. The component is destined for the aerospace industry, specifically for the Airbus A350. The theoretical part of the thesis analyzes the base of aluminum alloys as well as the machinery park of the company. The CNC centers MCFV 1060 and PICOMAX® 95, on which the part is manufactured, are discussed in more detail too. The practical part deals with creation of production process including toolbars. The end of the thesis is devoted to calculation of machine time needed for the component production.
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