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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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Study of the morphology of highly oriented pyrolytic graphite irradiated by argon ions
Komínek, Josef ; Kaspar, Pavel (referee) ; Sobola, Dinara (advisor)
The main task of this bachelor’s degree work is study of highly oriented pyrolytic graphite (HOPG) using atomif force microscopy, Raman spectroscopy and XPS spectroscopy. HOPG is layered material: atoms in one layer have stronger bong between themselves than two atoms in two neighbouring layers. Wide application options require further study. HOPG is now commonly used in nano-industry. It is used as a dimension standard. HOPG of A quality was processed in this work. In order to get accurate 3D data of sample surface, AFM measuring was done. 3D models of surfaces of various sizes are made. For these purposes was used free AFM data tool. Height parameters are used to describe topography. Got parameters are important for further study.
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Advanced methods of surface topography evaluation
Hroděj, Daniel ; Osička, Karel (referee) ; Píška, Miroslav (advisor)
This paper deals with the analysis of data obtained from the surface of aluminum alloy 7475-T7351 after face milling with a tool inclination of 1°. The theoretical part explains the basic principles of measuring the topography of the surface and instruments that are able to provide relevant data directly from the scanned part. The following part contains the methods of evaluating the information, especially using various types of parameters acquired from ČSN EN ISO standards. The practical part focuses on the data obtained from the sample surface using the Alicona IF-G5. This information determines the character of the surface texture with the tool inclination and the difference between the profile and surface parameters. There is also described surface texture in the tool path and on the edge of the tool path. In the final economic evaluation, the connection between the feed per tooth and the machining price is found.
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Assessment of surface roughness and its influence on fatigue life
Dziubek, Jan ; Chamrad, Jakub (referee) ; Horníková, Jana (advisor)
This thesis deals with influence of surface roughness on fatigue life. In the thesis, the evaluation of the surface roughness by the profile method according to the standard ČSN EN ISO 4287 is specified. Within the work, the roughness parameters of samples with different surface treatment were determined. Then, SN-curves were drawn for samples with different surface treatments and compared with each other.
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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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The study of the influence of process parameters on the roughness of the cut for flame laser cutting of stainless steel
Kučera, Václav ; Hála, Michal (referee) ; Mrňa, Libor (advisor)
Thesis presents a study of the influence of process parameters on the roughness of the cut surface. The test material is 1.4301, namely austenitic stainless steel. When a parameter is the surface roughness not change too much. In some samples there were defects in the form of cutting burrs. The graphs below show the estimated minimum change one parameter (the lowest point of the curve). As the most important parameter from a technological point of view, cutting speed, constitutes a major cost item compared to the auxiliary gas and power. For samples with a thickness of 2 mm and 3 mm has been achieved good results with decrease in the cutting rate of 30% percent, although when cutting the samples with a default rate was almost identical results. For samples with a thickness of 3 mm the best results were achieved by increasing the speed by 30 %, decrease the rate should be compared with the economy of the process to reduce surface roughness. For changes in the gas pressure was achieved the best values at a pressure increase of 30 %. When you change the performance of the best results are achieved by setting 100–90 % capacity.
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Advanced methods of surface topography evaluation for finishing technology
Adamus, Petr ; Sliwková, Petra (referee) ; Píška, Miroslav (advisor)
The main theme of this thesis is the surface topography evaluation. The theoretical part introduces the fundamental methods of evaluation, measuring instruments and describes profile and surface topographic parameters. In the practical part, the influence of different cutting conditions in high-feed face milling was researched on sample made of aluminium alloy 7475-T7351. For the surface topography evaluation of all samples the measuring device Alicona IF G5 was used. The last part of the diploma thesis is devoted to the economic influence of cutting conditions on the process of high-feed face milling.
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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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Machining of ceramic bodies using CAD-CAM
Kaplan, Lukáš ; Částková, Klára (referee) ; Kaštyl, Jaroslav (advisor)
The literature part of bachelor's thesis deals with ceramic materials based on Al2O3 and ZrO2, methods of sample preparation for consequent machining, different methods of machining, especially the technology of CNC machining in non-sintered and sintered state with their comparison. The thesis presents possible examples of the use of ceramic parts. The experimental part of the thesis deals with the machining of ceramic based on ZrO2 using different types of ceramic powders, methods of preparation and the choice of the sintered temperature in relation to its properties. The best results were achieved with SZ-3Y ceramic material sintered at 1550 °C for 2 hours, strength values were 1203 MPa, roughness of surface Ra was 126 nm a grain size was 382 nm.
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