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Factors affecting the quality of machined surfaces after milling operation
Černý, Libor ; Jaroš, Aleš (referee) ; Fiala, Zdeněk (advisor)
This diploma thesis deals with the final quality of the surface under variable working conditions during milling. The first part deals with the definition of qualitative parameters describing surface properties. This is followed by a brief description of the cutting resistance measurements. The thesis is complemented by experimental verification using front milling and its evaluation. The aim of the experiment is to determine the dependence of the surface quality and the size of cutting resistors under the variable working conditions of the machine that do not make a common part of the manufacturing processes.
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Prediction of suitable cutting conditions for machining of main steels
Beneš, Ondřej ; Fiala, Zdeněk (referee) ; Jaroš, Aleš (advisor)
In this thesis is described machining of barrel steels and determination of the most suitable cutting conditions for this process. In the theoretical part was characterized cutting process and explained problems of VBD wear, chip formation and roughness of the surface. There were also explained most common cutting materials and in the last part were described CVD and PVD coating methods. In the experimental part was measured force load during turning. There was also tested eight carbide cutting inserts from SECO TOOLS. During the tests were measured additional surface roughness values and taken chip samples as well. From the evaluated load force data were determined optimized cutting conditions for machining barrel steels and most suitable type of cutting insert.
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Finite element simulation of stresses in plasma-sprayed thermal barrier coating
Lacina, Zdeněk ; Slámečka, Karel (referee) ; Skalka, Petr (advisor)
Bachelor‘s thesis focuses on the study of stress states in thermal barrier coatings. A two-dimensional computational model of thermal barrier coating was created using ANSYS software, on which the process of cooling of thermal barrier from working temperature to room temperature was simulated .The stress distribution in ceramic layer was studied then. The output of this thesis is a description of the influence of roughness, amplitude and TGO layer on the stresses in a ceramic layer of thermal barrier. Matlab software was used to process the results.
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Techniques of thin layers deposition and characterization, their analysis using scanning electron microscopy
Kiška, Roman ; Moravčík, Igor (referee) ; Čupera, Jan (advisor)
My thesis is concerned with the application of thin films methods and it focuses on the method of PVD and CVD. Another part of my work is experimental, where two samples were preapared by magnetron sputtering and by method of gas phase deposition. The aim of the work was to compare their material properties with commercially produced samples. Severel parts were measured - nanohardness, adhesion, roughness and thickness. Theoretical part focuses on chemical and physical essence of the different methods of the deposition of thin films and on the description of material properties, that are essential for thin films. The practical part includes the description of depositional processes and of the characteristic techniques used in the practical part.
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Development of 3D metal printing process parameters for producing of the lattice structure
Jaroš, Jan ; Koutný, Daniel (referee) ; Vrána, Radek (advisor)
Selective laser melting (SLM) in additive technology, which allows production of lattice structures. Lattice structures are very difficult to produce using conventional methods. The main use of lattice structures is in aerospace industry and medicine for bone implants production. In this work influence of processing parameters (laser power, scanning speed) on properties (diameter, surface roughness, porosity) of struts is investigated. The processing parameters selection was based on single tracks test. In the first test, ImageJ was used to determine porosity of struts. In the second test porosity was analyzed with more accurate µCT technology. Both tests used 3D scanning technology to determine dimension accuracy and surface roughness of samples. The measurement results led to the detection of processing parameter „window“ where samles had the best combination of surface roughness and porosity. The best results were achieved with 225-275 W laser power and scanning speed of 1400-2000 mm·s-1.
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Assessment of runoff conditions on flow in the Morava river basin
Holá, Lucie ; Niklová, Věra (referee) ; Uhmannová, Hana (advisor)
The diploma thesis deals with the design of nature close to the flood protection of the city Prostějov at the confluence of the watercourses Romže and Hloučely and the flow Valova (Romže). In canculations there was solved capacity of individual sections and canculation of levels for one-year, five-year and twenty-year flow. For canculations there was used one-dimensional mathematical model HEC-RAS 5.0.3. Determination of roughness of bottom and slopes was based on personal visit. The result of this diploma thesis is evaluation of current state and proposal of a nature close to the flood protection in the individual streams in the city Prostějov. The thesis contains the calculation part and the drawing part documenting the proposed measure.
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Určování textury povrchu obráběné součásti
Hladký, Filip
The topic of the bachelor thesis is Determining the texture of the surface of the machined component I've dealt with the explanation of the basic concepts from the field of surface texture and detailed research of different methods of ma-chining. This is followed by a description of the methods for measurement of pa-rameter roughness Ra. In the practical part of the bachelor thesis are insights from the theoretical part are applied to the specific case of the measurement of the parameter of roughness for the three different components.
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Technologie broušení dřeva, stroje a nástroje
Slezáková, Světlana
The grinding process is important for treatment of the wood surface. There are many different machines for a sanding wood, whether manual or mechanical. By the correct grinding of a wooden surface it is achieved better final result. The thesis describes factors that influence the course of grinding. The main factors are the kind of wood, the moisture, the selected grinding tool and the technical condition of the machine. The main objective of the study is to determine and compare the change of surface roughness when changing the grit of the sanding belt and the grinding angle. There were chosen three angles at which the samples were grinded. The study also investigates relation between the coarse grit of the sanding belt and roughening of the surface. The research was conducted on the tree species beech (Fagus sylvatica). A second objective of the study is to prepare the background for the laboratory exercise and the lecture on the topic of grinding materials.
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Technika řezu stromů
Krupař, Petr
This bachelor thesis deals with comparing chain saws and handsaws in terms of their influence for roughness of laceration. There were tested six different kinds of chain saws and three handsaws which differ in technical specification, construction and used chain or blade. There were made samples of small-leaved linden wood (Tilia cordata) and ash (Fraxinus excelsior) by individual sections and counted resultant values of roughness according to used methods. Based on the resultant values, there was implemented the recommendation for practise.
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Adhesion of the materials for the horizontal marking
Šašinková, Daniela ; Dašek, Ondřej (referee) ; Varaus, Michal (advisor)
The presented bachelor thesis deals with the adhesion of materials for horizontal road marking in the case of renewal of marking and two-phase marking. Within the work specified parameters were measured and evaluated. The theoretical part describes the initial situation and is followed by the general characteristic of the horizontal road marking. Further, there are also described individual tests performed on horizontal road marking carried out within the presented bachelor thesis. The practical part deals with the preparation, production and description of the samples that have been used for this work. The evaluation of the measurements carried out on all testing samples of the marking follows. All evaluations are based on test results and photo documentation.
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