|
|
Evaluation of porosity in Al-alloy die-castings
Havel, Jiří ; Nová, Iva (referee) ; Čech, Jaroslav (advisor)
The aim of this diploma thesis is to analyse the porosity of die - cast cast that were made of the alloy AISi9u3 in iron-foundry Skoda Car Mlada Boleslav. The analysis and the sample comparisons are based on my own measurements and are also connected with previous diploma thesis which deals with that issue and was drawn up at Technical University in Brno. All measurements were statistically tested.
|
|
|
Optimization of diecasting process of an electric motor bear shield casting
Krňávek, Štěpán ; Kolmačka, Marek (referee) ; Roučka, Jaromír (advisor)
The present bachelor thesis deals with optimization of a die casting technology used to make a casting of an electric motor bear shield which is cast in the Siemens Elektromotory Ltd. foundry in the town of Mohelnice. There are foundry defects in the casting which are undesirable and must be removed. The introduction of the thesis is devoted to an analysis of the bear shield casting, its casting parameters, an alloy AlSi9Cu3(Fe) used and to problems resulting from the occurrence of defects in the casting. Subsequently, the die casting technology is explained, machines used in this technology and their new structural design are described, and the most frequently occurring defects in this technology and their causes are mentioned. In the following part of the thesis an x-ray analysis of the casting, a thermal analysis of the casting and a microscopic analysis of the defect cavity are carried out. On the basis of the analysis the casting defects have been identified as closed air - gas holes. To minimise the occurrence of the given casting defects several possible corrective measures have been suggested.
|
|
|
Evaluation of mechanical and structural properties of new block
Lefner, Jiří ; Nová, Iva (referee) ; Čech, Jaroslav (advisor)
The purpose of this dilploma thesis is to evaluate mechanical and structural properties of two types casts of Al-alloy (components of the engine block) which were made by different technologies. Die casting with local squeeze casting and without local squeeze casting. First of them is used in lot manufacture of the current engine block. The aim of the foundry is to change the technology and start to produce new block by the die casting without local squeeze casting. The samples were taken from the both parts (lower and upper part) of the current and the new engine block which are made in foundry of Skoda Auto a.c. in Mladá Boleslav. Sets of mechanical and structural properties were selected, evaluated and tested by statistical programs. It was used fifty casts of the engine blocks for the experiment.
|
|
|
Structure and Properties of Selected Magnesium Cast Alloys
Svozil, Libor ; Pacal, Bohumil (referee) ; Podrábský, Tomáš (advisor)
Microstructure and mechanical properties of AZ91 magnesium alloy after die cast (casting under pressure) and squeeze casting were comparated. The compare of incident phases, their microhardness, gas bubbles in the alloy, hardness and other mechanical properties of alloy are included in this work. For compare has been used a light microscopy, tensile test, hardness and microhardness measurements, image analysis and scaning electron microscopy.
|
|
| |
|
|
Strength analysis of mold for high-pressure casting
Ferenc, Filip ; Šotka, Pavel (referee) ; Vosynek, Petr (advisor)
This master thesis had been created at the instigation of Skoda Auto. a.s. tool design department, which designed a new concept of the diecast mold. For this new concept of construction mold was requested to describe its strain-stress behaviour. The main goal of this thesis was to run s-s analysis. According to results of s-s analysis the potentially risky location had been found and the recommendation of the design improvement had been made. The problem has been solved by Finite Element Method in software ANSYS Workbench. The output of the work is mainly used as a basis for the design of high-pressure casting molds of S. A. a.s.
|
|
|
Foundry technologies from the point of view of castings accuracy
Hýbal, Ondřej ; Vašťák, Patrik (referee) ; Horáček, Milan (advisor)
This bachelor’s thesis deals with various casting technologies, specifically about investment casting technology, evaporative-pattern casting and die casting. These technologies compares not only on achieving the smallest dimensional tolerances of the final casts, but also of other factors such as surface roughness, wall thickness and production economics. This thesis also describes casting accuracy in general and informs about the management strategy of Six Sigma.
|
|
|
Optimization of die casting technology for the casting of vacuum pump
Krňávek, Štěpán ; Kolmačka, Marek (referee) ; Roučka, Jaromír (advisor)
Diploma thesis deals with optimization of technological process casting a die cast, which is part of vacuum pump. The die cast is made from alloy AlSi9Cu3(Fe) in foundry KOVOLIT, a. s. There is a problem with inner defects at this cast. Solution of this thesis is to suggest suitable actions to minimize of incidence the defects in the cast. According to analysis of the defects in the cast these defects were classified as combination of shrinkages and gas holes. According to analysis causes of the defects are high temperature of die mould and closed air in die mould. As a result suitable actions were suggested – a change of the die mould tempering and a design adjustment of the cast. In case of implementing a new die mould in the manufacture a new gating system was designed. Suitability of the new gating system was assessed according to simulation of filling die cavity.
|
|
|
Evaluation of porosity in Al-alloy die-castings
Havel, Jiří ; Nová, Iva (referee) ; Čech, Jaroslav (advisor)
The aim of this diploma thesis is to analyse the porosity of die - cast cast that were made of the alloy AISi9u3 in iron-foundry Skoda Car Mlada Boleslav. The analysis and the sample comparisons are based on my own measurements and are also connected with previous diploma thesis which deals with that issue and was drawn up at Technical University in Brno. All measurements were statistically tested.
|
|
|
Evaluation of porosity in Al-alloy die-castings
Straka, Jakub ; Nová, Iva (referee) ; Čech, Jaroslav (advisor)
The purpose of this diploma thesis is an evaluation of die-castings porosity, eventually the evaluation of seats with local squeeze in connection with their mechanical and structural properties. The swatches of alloy AISi9Cu3 were taken from the engine block made by Škoda Auto Company, Mladá Boleslav. To the evaluation and the comparison of the results there were used value of porosity with own measure and other student´s thesis of Brno University of technology. Sets of mechanical and structural properties were selected, evaluated and tested by statistical programs.
|
guest ::
