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Optimized ceramic shell for manufacturing of aluminium castings by using lost wax technology
Mazůrek, Tomáš ; Vašťák, Patrik (referee) ; Horáček, Milan (advisor)
This diploma thesis deals with the possibilities of optimization of ceramic shell molds in the method of investment casting. In the first part is mentioned a complete technological process of the method with focusing on production and quality control of the ceramic shell and components, from which it is produced. The experimental part is divided into two parts, in the first are results of laboratory tests, which were tested both the current ceramic shell and shells which have been considered as a possible replacement. In the second section were verified conclusions of the experimental findings and recommendations of the laboratory results in pilot plant conditions.
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Investment casting - defects list
Šmatelka, Jakub ; Staňková, Markéta (referee) ; Mikulka, Vít (advisor)
This bachelor thesis deals with defects which can occurred during investment casting process. In the first part, there is briefly described investment casting process in Alucast s.r.o. company. List of all defects occurring during manufacture is described in the second part. This catalog includes majority of defects from the cast proposal to finishing operations. There are also described causes, consequences and corrective actions.
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Optimization of wax pattern technology in the company Alucast
Šmatelka, Jakub ; Cileček, Jarmil (referee) ; Horáček, Milan (advisor)
This diploma thesis deals with the problem of wax patterns manufacturing in investment casting technology (lost wax process). This technology is very sensitive to the exact execution in each phase of the whole process, from concept design up to the final casting expedition. During most operations, dimensional changes occur, which is affecting the accuracy of the final casting. No matter how big these changes are, but especially if they occur with the least variance. One of the first phases in this technology is making wax patterns. There are several ways of making the wax patterns and this thesis is describing two different methods used in the Alucast foundry. One is based on using “soft waxes” enabling using low pressure machines, the other one on the “hard waxes” where the injection machine with higher presses is being used (SOM). These two above mentioned technologies are compared in this work.
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Optimization of gating systems (their yield) in Al castings made by investment casting technology
Žižka, Jiří ; Šmatelka, František (referee) ; Horáček, Milan (advisor)
This diploma thesis deals with the optimization of gating systems of shape-complex aluminum castings produced by investment casting process. Two castings whose massive gating systems make problem with the use of liquid metal (so called yield) were chosen for optimization. Each casting is described in its own chapter. The individual subchapters deal with description of the original and newly designed gating system. Simulation, test castings, X-ray inspection and metallographic examination were performed for each variant. At the end of each chapter there is an evaluation of the results of the optimization of gating system.
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Investment casting – progressive foundry technology
Blažík, Petr ; Macků, Martin (referee) ; Mikulka, Vít (advisor)
The goal of this bachelor thesis is to bring special retrieval about possibilities of investment casting technology used for casting dimensional accurate products from aluminum alloys together with lost-wax process. The thesis deals with problems of the dimensional accuracy and the surface quality of casts produced by this technology. Further a thesis is focused on possibilities of increasing mechanical properties by the modification of casting procedure. At the end a thesis describes special technologies used for casting dimensional accurate aluminum alloys products used in aerospace industry, their principle and reachable mechanical properties.
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Optimizing the technology of Al casting manufactured by the "lost wax process"
Mikulka, Vít ; Vašťák, Patrik (referee) ; Horáček, Milan (advisor)
This diploma theses deals with possibilities of using numerical simulation for optimizing production of highly demanding thin-section casting produced by investment casting process. The casting made of aluminium alloy in which the manufacturing process was very problematic (occurrence of macro and micro shrinkages) has been chosen. By numerical simulation the existing technology has been analysed and based on this the possible reasons for defects found. This was later confirmed also by metallographic examinations. Following to this several options for a new technology were proposed and again by simulation checked their suitability. By comparing all above mentioned options two versions have been chosen in the end which was later tested in production with satisfactory results.
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Possibilities of using numerical simulations in investment casting technology
Čagánek, Radim ; Cileček, Jarmil (referee) ; Horáček, Milan (advisor)
The diploma thesis deals with the possibilities of using numerical simulation in investment casting technology. The first chapter of practical part deals with the use of simulations in the design of gating system for the shape-complex casting. At the same time, the practical part verified the accuracy of the simulation by test castings on which the X- ray inspection was performed. The results showed that the occurrence of internal defects predicted by simulation corresponded to the locations in the test casts. Next part of the thesis describes improvement of the use of liquid metal (so called “yield”) by numerical simulations. Two specific castings were chosen to perform simulation of current and newly designed variant of the gating system.
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Dimensional stability of investment Al castings
Úředníček, Lukáš ; Cileček, Jarmil (referee) ; Horáček, Milan (advisor)
The aim of this paper is to compare a bottom filling of a ceramic form made by lost wax process and a top filling conventional method. A computer simulation of filling and casting solidification will contribute to this comparison. The comparison includes evaluation of readings DAS and characteristic readings of porosity with chosen varieties of casting. The results show that the readings DAS did not change much but characteristic readings of porosity were much better at bottom filling. The computer simulation also showed a certain contribution in the field of model smelting technology.
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Optimization of gating systems (their yield) in Al castings made by investment casting technology
Žižka, Jiří ; Šmatelka, František (referee) ; Horáček, Milan (advisor)
This diploma thesis deals with the optimization of gating systems of shape-complex aluminum castings produced by investment casting process. Two castings whose massive gating systems make problem with the use of liquid metal (so called yield) were chosen for optimization. Each casting is described in its own chapter. The individual subchapters deal with description of the original and newly designed gating system. Simulation, test castings, X-ray inspection and metallographic examination were performed for each variant. At the end of each chapter there is an evaluation of the results of the optimization of gating system.
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Possibilities of using numerical simulations in investment casting technology
Čagánek, Radim ; Cileček, Jarmil (referee) ; Horáček, Milan (advisor)
The diploma thesis deals with the possibilities of using numerical simulation in investment casting technology. The first chapter of practical part deals with the use of simulations in the design of gating system for the shape-complex casting. At the same time, the practical part verified the accuracy of the simulation by test castings on which the X- ray inspection was performed. The results showed that the occurrence of internal defects predicted by simulation corresponded to the locations in the test casts. Next part of the thesis describes improvement of the use of liquid metal (so called “yield”) by numerical simulations. Two specific castings were chosen to perform simulation of current and newly designed variant of the gating system.
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