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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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Optimization of foundry technology for the production of piston from Al alloy
Poláček, Adam ; Pernica, Vítězslav (referee) ; Krutiš, Vladimír (advisor)
The aim of work is to optimize the casting solidification technology to reduce or completely eliminate defects. The literary part of the work deals with materials, production technology and defects in the pistons of internal combustion engines and compressors. In the design part of the work, an analysis of the occurring defects is performed. X-ray examination and the cut of the piston are conducted to investigate the causes of their formation. Subsequently, the simulation of the current production technology is carried out and technological modifications to the cooling process are proposed. These modifications are verified through simulation and in the conclusion are compared in terms of their effectiveness in reducing the occurrence of defects.
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Production of a prototype casting of aluminium rotor with an insert using precision casting technology
Záviský, Matěj ; Jelínek, Radim (referee) ; Krutiš, Vladimír (advisor)
This thesis focuses on the production of aluminium castings with steel inserts produced by hybrid investment casting using additive technologies. The main objective is to analyse the production possibilities and quality of the casting, with emphasis on the shell cracking issue during high temperature firing of the model. The thesis deals with innovative techniques in investment casting and process optimization to achieve a strong metallurgical bond between materials. Bimetallic components can be used to achieve optimum application specific performance and structural integrity in various industry sectors. The use of digital technology and simulation software has also contributed to improving the final casting quality.
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Optimization of production Zn alloy casting by HPDC technology
Odehnal, Pavel ; Kaňa, Václav (referee) ; Krutiš, Vladimír (advisor)
The master thesis deals with the analysis and design of a solution for removing defects on a selected zinc casting. The theoretical part of the thesis is focused on the description of individual types of zinc alloys, which are most often used in common practice. It is followed by a description of the technology of high-pressure casting and what types of technologies and machine designs for high-pressure casting are standardly used in operation. The most common defects in high-pressure die casting are also described. The practical part of the thesis is focused on the analysis of a defect in a selected manufactured zinc casting with the determination of which defect it is. A non-destructive test is carried out on the casting to analyse the rate of occurrence of this defect, followed by an analysis using numerical simulation, and making several modifications to reduce the rate of occurrence of this defect.
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Casting production of an optimized inlet shape of pneumobile engine pneumatic cylinder
Bouchner, Jan ; Záděra, Antonín (referee) ; Krutiš, Vladimír (advisor)
Presented bachelor's thesis deals with production of a pneumatic component using hybrid investment casting technology. This method combines investment casting with additive technologies. The manufactured component, called cap-end, supplies compressed air to the pneumatic drive of a racing car. Complex design of this component was created using computer fluid dynamics optimization. This design was delivered by the Pneumobile racing team Brno. Presented thesis further contains a technological consideration taking into account solidification direction, on the basis of which the delivered geometry was modified. Manufacturability of the component is verified by a numerical simulation in the ProCAST environment. This thesis also describes printing process of a combustible model using fused deposition modelling technology. The combustible model is used in the production of a ceramic shell. Using said ceramic shell AlSi10Mg alloy casting was made. The component had to meet the requirements for leak tightness after machining and subsequent assembly. The leak tightness is assessed here as a pressure drop in a closed circuit measured over time. Furthermore, the effect of the cap-end on properties of the racing car in relation to the original geometry was investigated. The comparison is made on the basis of the race car's unloaded wheel speed measurements. The outcome of the thesis is a functional cap-end component that validates the results of a scientific article published by members of the Pneumobile racing team Brno.
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Insulating materials in foundry technology
Slowiaczek, Kamil ; Krutiš, Vladimír (referee) ; Myška, Martin (advisor)
The thesis deals with materials that ensure the insulation of foundry furnaces and ladles. The first part discusses the properties that most affect the insulation capacity. The second chapter focuses on the overview and characteristics of refractory materials. In the next part of the thesis, the most used insulation materials are named and approached. Finally, the thesis deals with the composition of the lining of the electric arc furnace, ladles and the rammed lining of the induction crucible furnace.
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Use of 3D technology in foundry industry
Straka, Pavel ; Krutiš, Vladimír (referee) ; Pernica, Vítězslav (advisor)
The work is focused on replacing a faulty briefcase handle with an aluminium substitution. The handle is fabricated with the help of reverse engineering, where the handle is scanned with a 3D scanner. With that information, a model copy of the part is made, which is 3Dprinted from PLA and PolyCast materials. These handles are used as expendable models, which are used for casting using an “investment casting” method. Those are made from an AlSi10Mg alloy. Theoretical part deals with additive technologies, which are mostly used for manufacturing of foundry models and moulds. Next, the basic principles of 3Dscanning are described, and the term reverse engineering is also explained.
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Introduction of special die lubricant - micro spraying into the conditions of high pressure die foundry
Šromota, Michal ; Roučka, Jaromír (referee) ; Krutiš, Vladimír (advisor)
The master thesis, consisting of a theoretical and practical part, focuses on the issue of high pressure die casting, specifically the treatment of the die using micro spray technology. The goal of the thesis was to map the processes that need to be changed in the high pressure die casting foundry in order to successfully implement the use of micro-spraying. The practical part describes the introduction of micro spray technology in the foundry KOVOLIT Modřice a.s. In this case a transition from the conventional spraying method to the micro-spraying is made. After testing, both stable production and the expected savings associated with the operation of micro-spraying were achieved on the selected casting, and therefore it was decided to convert the production of the selected casting to this technology.
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Influence of Cyclone process parameters on the quality of ceramic shells
Lederer, Vojtěch ; Šustek, Petr (referee) ; Krutiš, Vladimír (advisor)
Diploma thesis contains introduction into shell drying, its monitoring and influence on shell properties. The thesis works with the Cyclone machine described further. The shell drying process in the machine and experiments are carried out broadening understanding of functions and parameters of rapid drying process. Experiments comparing courses of drying under respective settings of Cyclone and under common drying in air-conditioned room are carried out. Also mechanical properties of commonly dried shells and shells made by the Cyclone machines are compared. The positive effect of the machine on the ultimate strenght of dried shells and positive effect on the drying speed has been confirmed.
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Numerical simulation of core blowing
Abraham, Martin ; Brázda, Zdeněk (referee) ; Krutiš, Vladimír (advisor)
This work focuses on simulation of core blowing into the core boxes. Mechanical production of cores is now a normal part of any foundry. But can never predict whether core can make right the first time. This situation can be used as a helper QuikCAST simulation program that is able to handle the issue and deal with and can find the optimal basis.
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