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Proposition of casting technology of aluminium manifolds cast by tilt method
Spáčil, Ivo ; Kaňa, Václav (referee) ; Roučka, Jaromír (advisor)
Description of the theoretical factors for casting into metal molds. For thin-walled castings it has turned out that the most advantageous method is tilt casting. Tilt casting reduces the turbulence of the melt and reaches a directed solidification. Two molds were tested and measured for the experiment. During measuring the temperature regime was established lower temperature of the pouring basin than the other parts of the mold, which could cause a many of defects. The verification of mold technology has been performed. To achieve the accuracy of the casting, it is necessary to respect the different shrinkage according to the shape of the casting.
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Influence of ceramic filtrers on metal streaming in running systems
Vymyslický, Jakub ; Láník, Boris (referee) ; Roučka, Jaromír (advisor)
This thesis deals with influence of ceramic filters on metal streaming in running systems. The purpose of this thesis is to investigate the influence of porosity, thickness of ceramic filters and also viscocity of molten metal on mold filling. Hydraulic resistance of ceramic filters and possibility of its use in numeric simulation is also tested. At the beginning of the thesis there is theoretic analysis of filtration which inlcudes inclusions in cast irons, filtration matters, gatting systems design, hydraulic resistance and numeric simulation. The second experimental part of this thesis is focused on measuring shedding of molten grey cast iron and ductile iron through gatting systems with filters which are labelled VUKOPOR S. The experimental part then deals with evaluation of experiments results, calculation of hydraulic resistance and numeric simulation with the use of measured data.
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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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High temperature corosion of SiMo type ductile iron
Viskupič, Adam ; Kaňa, Václav (referee) ; Roučka, Jaromír (advisor)
While using iron castings behind temperature of 500 C 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 C. Thesis set up chemical microheterogeneity, properties, high temperature corosion and microhardness
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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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Prediction of mechanical properties of iron castings by means of numerical simulation
Filipek, Szymon ; Kotas, Petr (referee) ; Roučka, Jaromír (advisor)
The aim of this thesis was to design optimization of the amount of alloying elements (copper and molybdenum) in liquid alloy, which improve mechanical properties of the grey cast iron. An adjustment was made to exceed requirement for a minimum strength in the stressed area. The strength limit was exceeded by approximately 60 MPa. Foundry simulation software MAGMAsoft was used for theoretical optimization. Conformity between the mechanical properties evaluated by simulation and the measured values of hardness, tensile strength was confirmed in the first step of the experimental part. A draft of optimization was created in the second step, which led to savings of the alloying costs.
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