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Plating of materials for 3D printing
Jančí, Jakub ; Bayer, Robert (referee) ; Starý, Jiří (advisor)
This bachelor's thesis deals with an introduction to the issue of plating plastic parts printed on a 3D printer. The thesis includes an overview and comparison of 3D printing technologies and materials, particularly from the perspective of chemical resistance, plating, and soldering, which are used in 3D printing manufacturing technology. The thesis provides a detailed description and discussion on the application of metal coatings to printed objects made from various 3D printing materials. The practical part of the thesis focused on the production of test samples and their subsequent plating process.
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The separation of microplastics from environmental matrices
Pařízková, Mia Victoria ; Řezáčová, Veronika (referee) ; Doležalová Weissmannová, Helena (advisor)
This bachelor’s thesis deals with methods of separation microplastics from soil and the follow up application of quantitative methods of gravimetry, ATR-FTIR and Py-GC/MS. Samples containing model soil and PET or PLA microplastics of different concentrations were prepared. These samples were separated using potassium carbonate solution of known density. The effectivity of separation was measured by gravimetry. The samples were also analysed using ATR-FTIR and Py-GC/MS methods the results of which were compared by correlation coefficients. It was found that ATR-FTIR is a more suitable method, thus it was used for analysis of prepared samples of ten different real soils and PET or PLA microplastics.
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Optimization of infill selection with an emphasis on maximum dynamic resistance
Konvalina, Michal ; Svoboda, Petr (referee) ; Jopek, Miroslav (advisor)
The thesis deals with the study of the effect of different wall thicknesses of 3D printed infill patterns at constant cross-sectional area on their final properties under static and dynamic loading. Based on literature study, two experimental methods are chosen. The quasi-static test and the Taylor anvil test. For the experiment, square and hexagonal grid specimens are printed using FDM technology from PLA material. Quasi-static test is used to measure the static properties such as maximum compressive strength, yield stress, modulus of elasticity and to derive material model of Johnson-Cook. The dynamic impact test TAT is used to evaluate different types of patterns at high impact velocities. In ANSYS, the specimens that resisted the highest impact velocities in TAT are simulated and strain rate sensitivity parameter is optimized for the specific velocity. The highest dynamic resistance was achieved by a square infill pattern with wall thickness of 0,4 mm at an impact velocity of 37 ms-1.
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Preparation and characterization of lightweight polymer materials with hierarchical cellular structure
Režnáková, Ema ; Ondreáš, František (referee) ; Lepcio, Petr (advisor)
The asymmetrical arrangement of cellular structure allows for an accurate functional adaptation at all levels of hierarchy, which derives excellent features for the development of new materials. The main objective of introducing a hierarchy into cellular structures is to improve the mechanical behaviour of the material while maintaining its elastic properties. A part of this work is devoted to the literature review related to the lightened cellular polymeric materials with hierarchical cellular structure. The rest is focused on the preparation of PLA based polymer structures using 3D printing, followed by a saturation in CO2 and a foaming in a silicon oil at elevated temperature. Samples were prepared from natural and white PLA filaments. Based on a series of experiments, optimal conditions for the saturation and foaming process were identified. Through 3D printing and foaming, a one-, two- and three-level hierarchy was introduced into the beam-shaped samples and the effect of the internal cell arrangement on the strain response of the material was examined by the means of a mechanical three-point bending test. Increasing the level of the hierarchy led to an increase in material resistance, which resulted in high values of strength and strain energy (toughness) based on the samples density. The best results were achieved by samples with “sandwich” structure with three levels of hierarchy and 30% filling. Despite the shorter plateau, there was a significant increase in strength and strain energy compared to gradient structures. At the same time, the contribution of the polymer structures prepared in this field of research was demonstrated by comparison with the theoretical model.
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Experimental evaluation of appropriate FDM technology for UAV production
Hubáček, Jan ; Klement, Josef (referee) ; Dvořák, Petr (advisor)
This bachelor thesis deals with material analysis and design of technology for Fused Deposition modelling 3D printing method of unmanned aerial vehicles. Nine materials which are suitable for this application has been tested. Tension test has been used to determine mechanical properties of each material according ISO standards for plastics. Material had to met certain criteria, which are important for 3D print of aeroplanes, to pass to the next stage of experiment. Next three-point flexural test of wing has been used. In this test has been tested two glued sections of wing root and one separate section of wing. Results of tensile test and flexural test were compared and evaluated. It was discovered that material PLA, which is commonly used for printing aeroplanes, has not been overcome. Materials that seems to have better mechanical properties has been disadvantaged for its bad properties in 3D printing process.
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Surface changes based on FDM printing parameters
Čada, Jiří ; Sliwková, Petra (referee) ; Zemčík, Oskar (advisor)
This thesis deals with a construction of modified RepRap 3D printer Rebel II which operates with Fused Deposition Modeling technology and selection of suitable criterion for printing. It mainly focuses on the temperature of the material being printed and speed of printing for three selected materials. Materials were selected based on availability in the market and their application. An experiment, focusing on surface changes of products as well as on the look of a fibre after passing through a nozzle, was performed.
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Testing of selected material properties for 3D printing
Čáslavský, František ; Mačák, Martin (referee) ; Vyroubal, Petr (advisor)
This thesis deals with 3D printing, materials used for 3D printing, testing of the materials and learning their real parameters. Goal of the thesis is comparing selected materials, executing series of mechanical test and selecting suitable material for printing high-quality plastic parts for use in automobiles, especially for reproduction of parts that are no longer made for oldtimers and for use in motorsport.
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Gears made by 3D printing
Bělota, Martin ; Sedlák, Josef (referee) ; Kalivoda, Milan (advisor)
In the course of this work, the issue of 3D printing focused on the production of gears is addressed. The goal is to create gears based on designed gear models using 3D FDM printing technology. The theoretical part of the work describes the technology of 3D printing, including materials used for printing and selected technologies of 3D printing. Furthermore, the parameters of spur and bevel gears are described in the work because the practical part deals with them. The practical part of the work focuses on the production of gears from design, construction, preparation of the production process to the printing of the prototype and finishing of the prototype.
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