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Optimization of Machining Technologies for Special Applications
Ohnišťová, Petra ; Maňková, Ildikó (referee) ; Neslušan, Miroslav (referee) ; Píška, Miroslav (advisor)
This thesis is focused on the optimization of the milling technologies for special applications with respect to the required fatigue properties of aircraft components. The theoretical part of the thesis describes in detail the key features of the high-speed and high-feed milling, surface integrity after milling and fatigue characteristics of the studied component. The key aim of the work is devoted to the analysis of the influence of the cutting conditions of the high-speed peripheral and high-feed face milling of the bottom wing panel from aluminium alloy 7475-T7351 on the surface integrity in relation to the final fatigue properties. Therefore, the part of the work is a study of metallographic structure of the material, measurement of the accompanying machining phenomenon and quantities, advanced analysis of the surface integrity (amplitude characteristics, S-N parameters), manufacturing of the highly accurate fatigue samples and fatigue testing. Furthermore, the development of sample damage during in situ tensile loading and the development of sample damage during cyclic in situ fatigue tensile loading is also studied. The achieved results and fractography of fracture surfaces show that the studied cutting conditions have a significant effect on the quality of machining and resistance to mechanical stress, but they are not a decisive factor in terms of the fatigue crack nucleation. The effect of the achieved topography for the studied cutting conditions is suppressed by the presence of large intermetallic inclusions (Al7Cu2Fe; Al-Cr-Fe-Cu-Si) with a size from 2 µm to 20 µm, being the origin on the fatigue crack nucleation.
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Application CAD/CAM software hyperMILL for machining
Šebesta, Vít ; Sliwková, Petra (referee) ; Polzer, Aleš (advisor)
The main aim of this thesis is to acquire basic knowledge of CAM program hyperMILL 2019 with comparison of the ball nose end mill and circle segment end mill with taper form, economical evaluation and than make force analysis of specimen from aluminium alloy by milling with spindle moulder. Another aim of this thesis is also an analysis of force effects and force directions of the milling tool, advantages by using the circle segment end mill with taper form, the most common types of aluminium alloys and their mechanical properties and next comparison of CAM program hyperMILL with other selected program in the theoretic part.
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Influence of exothermic sleaves on solidification of aluminium alloys
Zajíček, Roman ; Krutiš, Vladimír (referee) ; Roučka, Jaromír (advisor)
The master’s thesis deals with the influence of the exothermic risers on the solidification of aluminum alloys. The work is divided into three parts. The first theoretical part describes the differences of properties of cast aluminum alloys compared to other based metals, especially iron alloys. It also describes the methodology of designing risers, composition of exothermic mixtures and finally gives an overview on the simulation programs on the market, their application in foundry practice and briefly explains how to define the material in the simulation program ProCAST. The second part describes the experimental measurement of the solidification time of aluminum alloy AlSi7Mg0,3 in the sand form with exothermic riser. The final section describes the simulation of experimental measurements. Further with help of simulation software it is tried to find the general principles that have an influence on feed module rate of exothermic riser.
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Sports car for people with disabilities
Lopušek, Dávid ; Růžička, Bronislav (referee) ; Brandejs, Jan (advisor)
The master thesis deals with the engineering design and realization of a sports electric vehicle for disabled people. The first part of thesis summarize competitive vehicles on market and also the necessary theoretical knowledge for the design phase. After analyzing the research and determine the resulting vehicle concept follows the draft design. In this section based on calculations was chosen the solutions and necessary components for a vehicle. The following section describes the structure of the vehicle in implementing selected components. In conclusion, the evaluation of the proposed solution.
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Manufacture of optical mirrors for high-frequency antenna
Muzikant, Dušan ; Bumbálek, Bohumil (referee) ; Sedlák, Josef (advisor)
This thesis deals with problems with manufacturing of high frequency elliptic and hyperbolic optic mirrors, which makes one of the most important functional parts of parabolic satellites made for biggest and highest placed international astronomical radio-telescope in the world - ALMA, which is built on Chajnantor plateau in Chille in South America. Individual chapters are designed in the flow of technological process of manufacturing, containing theoretical and practical analysis of the problems. Content of the thesis leads especially to description and clarification of individual causes of problems during manufacturing.
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Evaluation of corrosion on selected aluminium alloys
Skýba, Pavel ; Tulka, Jaromír (referee) ; Pacal, Bohumil (advisor)
The thesis focuses on the corrosion research of AlCu4Mg1 aluminium alloys of square shape and sheet metal coated in 99.5% aluminium. The theoretical part deals with the characteristics of aluminium, the classification and naming of aluminium alloys and the impact of admixtures on aluminium alloys. In the following chapter a general introduction to metal corrosion, its differentiation according to the type of corrosion attack, mechanisms of corrosion, the impact of corrosive environment, according to the choice of anti-corrosion protection, etc. is given. The main part is devoted to the corrosion of aluminium with a special importance of the impact of admixtures on aluminium alloys, the types of corrosion attack, the impact of corrosive environment as well as of the anti-corrosion protection of aluminium alloys. The corrosion tests in controlled atmosphere are considered in the next chapter, while the last one deals with the evaluation methodology of the process of corrosion. At the beginning of the experimental part all the used samples and materials are introduced. The thesis continues then with an overview and a description of the methods used for experiments. The measurement procedure and the results of the experiments are presented in the following chapter that focuses on the metallographic analysis of the aluminium alloy samples before the experiment and after the corrosion attack. The main part of the chapter deals with the dependence of corrosion speed of the individual aluminium alloy samples on time after being exposed in the climate chamber and the salt fog chamber
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Study on dependency of the weld geometry on process parameters in laser hybrid welding of aluminum alloy
Wojnar, Michal ; Kubíček, Jaroslav (referee) ; Mrňa, Libor (advisor)
A study carried out in the bachelor 's degree in engineering technology deals with changes the geometry of the weld technologies created laserTIG . The theoretical part provides an overview of the basic characteristics and advantages of welding technology laserTIG a summary of the issues welding of aluminum alloys. The experimental part consists in the execution of fifteen test welds on a sheet of Al alloy 2024 tl . 3 mm. From the measured values of individual welds were prepared according to the depth and width of the seam TIG welding current at a constant laser power and dependence on a specific area of the weld heat input Qs. By comparing the dependencies have been demonstrated theoretical advantages of laser hybrid technology , which consist mainly of increasing the welding speed and lower heat load of the welded material. Using the laser hybrid welding for welding of aluminum alloys proven advantageous.
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The effect of plastic strain of the reinforcement of aircraft panel made from aluminium alloy on the corrosion process
Valoušek, Tomáš ; Tulka, Jaromír (referee) ; Pacal, Bohumil (advisor)
This bachelor thesis is focused on study of corrosion of reinforcement panel of aircraft in environment of salt fog. The reinforcement material is aluminum alloy AlZnMgCu1,5 after solution annealing, release stress relieving and artificial aging, can be slighly deformed to compliance limit deviation. Material is not provided with any coating. The aim was to find out what is the effect of plastic deformation on the corrosion behavior of this alloy. In the experimental part of this thesis were studied the size and type of corrosion attack of samples with different plastic deformation. These values were furhter processed, evaluated and were drawn from them conclusions.
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Al-alloy die-castings for automotive industry
Havel, Jiří ; Nová, Iva (referee) ; Čech, Jaroslav (advisor)
This search is concentrated on Pressure-castings of aluminum alloys for the automotive industry. In the theoretical part of this topic is described in terms of technology for casting aluminum alloys with a focus on high-pressure casting of aluminum alloy AlSi9Cu3 and methods of detecting residual stress. In the experimental section is a sample of residual stress measurements on samples cast alloy AlSi9Cu3.
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