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Influence of filters on running of metal flow
Makalouš, Jakub ; Veverka, Aleš (referee) ; Roučka, Jaromír (advisor)
This study deals with influence of filters on running of aluminum metal flow. The main objective was to describe hydraulic resistances of assorted filters and running of silting filters by inclusions. Theoretical part generally describes filtration process and also filtration from the point of view of aluminum alloys and the most important characteristics of each type of alumina inclusions. Experimental part deals with flow rate tests, influence of filters on gassiness of melt and metallographic analysis. It was find out, that filter GEPHAL made minimal hydraulic resistance, on the other hand ceramic foam filters type LD made the maximal hydraulic resistance. It is necessary to reduce filtration surface for study running of silting filters by inclusions. Metallographic analysis showed amorphous alumina film inclusions, spinell Al2O3.2MgO, sludge and carbide of silicon.
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Thermo-physical parameters of exo-sleeves and their application in simulation programmes
Zajíček, Roman ; Kuzma, Zbyněk (referee) ; Roučka, Jaromír (advisor)
Thesis discusses exothermic sleeves. The first chapter briefly described the defects can occur during solidification. Further, there are provided methods for removing these defects. The method is described in detail using risers with an emphasis on the exothermic sleeves and thermo-physical parameters characterizing these sleeves. It also describes the influence of these parameters on the accuracy of computer simulations. In the final part of the work is done measuring of the real casting, which is then simulated in the Quikcast.
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Optimation of inoculation process of ductile iron
Ulm, Daniel ; Pecina, Vladimír (referee) ; Roučka, Jaromír (advisor)
The master‘s thesis deals in theoretical part with the casting classification, ductile iron casting, its inoculation and modification and quality evaluation using thermal analysis, image analysis and testing of mechanical properties. The aim of the practical part was to test the effects of preconditioning on the properties of ductile iron and to find out whether it is able to replace the current method of inoculation or to increase the mechanical properties of ductile iron castings. The state of the ductile iron was under control by spectral and thermal analysis. The mechanical properties and image analysis were checked on finished casting.
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Influence of degasing on casting quality by high pressure casting
Míšek, Jakub ; Kolmačka, Marek (referee) ; Roučka, Jaromír (advisor)
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.
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Manufacture and properties of SiMo cast iron
Abramova, Elizaveta ; Král, Vojtěch (referee) ; Roučka, Jaromír (advisor)
While using iron castings behind temperature of 500 oC namely at cyclic heat straining, degradation of structure and breaching iron castings. For this purpose introduce cast iron with content of Si and Mo. Focusing on improvement of SiMo51 for increased high-temmperature corrosion-and fatigue life in exhaust-gas temperatures up to 800 oC. Thesis set up survey types alloys, properties, and way of casting production.
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