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The use of small punch tests for materials with a higher level of structural inhomogeneity
Gordiak, Michal ; Řehořek, Lukáš (referee) ; Válka, Libor (advisor)
Master's thesis deals with evaluating applicability of correlation relationships between material characteristics determined by Small Punch Test and standard tensile test for material AlSi7Mg0,6 manufactured by casting and technology SLM. Results of Small Punch Tests are correlated with yield strength, tensile strength, elongation, and Young's modulus of elasticity. For each material characteristic various correlation methods are compared, while for each method corresponding coefficients are determined. Consequently, the applicability of individual methods is evaluated by substituting coefficients determined by various studies. Primarily analyzed are correlation methods for which future normalization is expected. The results of master's thesis show that structural inhomogeneity caused by SLM process does not result in high inaccuracies in determining material characteristics. Larger impact on material characteristics has high porosity, which was identified in cast material and led to significant deviations in evaluating tensile strength and elongation.
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Cavitation erosion mechanisms
Kotoulová, Helena ; Kozák, Jiří (referee) ; Rudolf, Pavel (advisor)
Předložená bakalářská práce se zabývá mechanismy kavitační eroze a je rozdělena na dvě hlavní části. Teoretická část popisuje princip kavitace, způsob jejího vzniku a především kolaps kavitačních bublin, který negativně ovlivňuje povrch obtékaného tělesa (např. na hydraulických strojích). Z tohoto důvodu je nutné podrobně studovat účinky kavitační eroze. Experimentální část je věnována testování kavitační eroze na kovových a plastových vzorcích vytisknutých na 3D tiskárně. Plastové vzorky byly srovnávány navzájem mezi sebou, kovové vzorky z 3D tiskárny se vzorky odlitými. O vlivu kavitační eroze na součásti vytisknuté na 3D tiskárně je stále ještě málo informací, i když se jedná o velmi progresivní a stále častěji používaný typ výroby.
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Effect of layer thickness on critical angle of additively manufactured lattice structures
Nosek, Jakub ; Vrána, Radek (referee) ; Vaverka, Ondřej (advisor)
Aim of this work is to describe the effect of a layer thickness on critical angel of a lattice structures manufactured by SLM technology. The effect of layer thickness was investigated on single struts and on lattice structures made from stainless steel 316L. Better geometrical accuracy could be obtained, if the smaller layer thickness is used. Less attached powder particles on downskins was also observed on lattice structures. Thanks to this thesis, it is possible to determine, if it is meaningful to decrease the layer thickness in order to improve manufacturability of lattice structures even with higher manufacturing time.
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Heat treatment of aluminum alloy AlSi7Mg0,6 fabricated by metal 3D printing
Zabloudil, Jan ; Malý, Martin (referee) ; Koutný, Daniel (advisor)
Author tries to obtain new information about the influence of different heat treatments on SLM fabricated AlSi7Mg0,6 alloy, its mechanical properties and residual stress. For this purpose were chosen parameters of heat treatment based on previous research of other authors. With the use of normalised tensile strength test specimens and special specimens for analysis of deformation caused by the residual stress were the influences studied. Author checked the influence of stress relieving annealing, parameters of precipitation hardening and artificial ageing on mechanical properties and residual stress in the material. Results can help fabrication of studied material to receive required properties and eliminate the deformation caused by the residual stress.
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Modern trends of production Al-based castings
Kovář, Jan ; Kaňa, Václav (referee) ; Krutiš, Vladimír (advisor)
This bachelor thesis is a recherche discussing new methods of the production al-alloy castings, which are mainly developed for the needs of automotive and airspace industry. The described methods are semi-solid casting and metal-matrix composites as the approaches of slurry production and squeeze casting and V-process as the approaches of casting. Further are described SLS, SLM and MJF methods of rapid prototyping and the structure of SLMed AlSi9Cu3 alloy is observed.
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The construction of the magnetic metal powder separator
Papaj, Lukáš ; Suchý, Jan (referee) ; Paloušek, David (advisor)
This thesis deals with the design of construction for recyclation metal powder, which is used in multi-material 3D printing with SLM technology. More specifically it is separation of mixed metal powders by magnetic separator, which is capable of separating two powders with the same distributions. Based on knowledge from industrial separators and successful experiment method of separating with magnetic drum was chosen, on which is equally driven metal powder from vibrating feeder. In executed experiment was discovered, that the method is appropriate for separating non-magnetic powder but for high quality separation of magnetic powder must be adjusted speed of feeding. Next was processed drawing documentation for this variant. By this documentation can be separator assembled and used in laboratory for separating metal powders.
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Design for production of analog watch case
Vilímovský, Daniel ; Kouřil, Karel (referee) ; Sedlák, Josef (advisor)
The aim of this bachelor thesis is a brief introduction to the watch industry and the characteristics of Rapid Prototyping. The practical part is focused on creating models of individual watch components in 3D parametric program Autodesk Inventor and following production by various methods on 3D printer. Part of the thesis is also assembly, including the watch movement installation. The thesis is concluded with a technical-economic evaluation and comparison with currently used production methods.
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Development of process parameters of Selective laser melting technology for the production of thin-walled iron parts
Šreibr, Vít ; Dočekalová, Kateřina (referee) ; Paloušek, David (advisor)
The thesis deals with the processing of pure iron by Selective laser melting technology as a material with good electromagnetic properties. The main area is the optimization of the production of thin-walled samples, which monitor the influence of process parameters on the thickness and quality of the wall surfaces. In addition to the perpendicular walls, walls built at an angle of 45° are also examined. Another phase of the thesis is the determination of process parameters for bulk bodies to achieve the lowest porosity and high surface quality. An important part of the research is the application of acquired knowledge in the production of samples designed to test magnetic properties as well as part for a specific application. These considerations concern not only the setting of the printing parameters, but also the heat treatment and its influence on the magnetic and mechanical properties of the material. Mechanical properties were determined by tensile tests and hardness tests. All samples were made on a SLM 280HL using a 400W ytterbium laser.
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Design of injection molding cooling insert for manufacturing by Selective Laser Melting
Tekeľ, Richard Martin ; Vrána, Radek (referee) ; Koutný, Daniel (advisor)
This bachelor thesis focus on design of a cooling insert so the current mold cycle time will be reduced and it will be possible to manufacture the insert by SLM. Proposed modification includes 1 cooling line with non-circular cross section and disrupt empiric cooling line design recommendations. A research into differences of conventional and additive manufacturing of injection moulding inserts was conducted as well as into theoretical principles needed for a design of cooling lines and preview of similar solutions for the given task. After simulation of current state and obtaining a value of current cycle time, 3 different designs of cooling line were chosen and simulated in order to pick the most suitable one. This cooling design was afterwards modified to get conformal shape and lower distance from critical spot. The last part of thesis interpret the results from simulation of the final cooling line design and estimation of safety against fatigue failure.
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Processing of magnesium alloys using selective laser melting
Kaščák, Pavol ; Paloušek, David (referee) ; Suchý, Jan (advisor)
The processing of magnesium-based materials with Selective laser melting technology is due to its high reactivity in the initial stages of development. This bachelor thesis deals with the elucidation of impacts of individual process parameters in processing of magnesium alloys on the resulting material porosity. The aim is to develop initial experiments for the shift in the processing of magnesium alloys by additive technologies. The theoretical part contains an insight into the SLM technology and an overview of the current state of knowledge of processing of magnesium alloys by this technology. By the analysis of the theoretical part, the main volume test of this thesis has been designed. The selected material for this test was the biodegradable magnesium alloy WE43. According to the author's knowledge, no research has been published on this alloy so far. Based on the results of the experiment, the dependencies of the individual process parameters were made on the resulting relative density of the samples. At the end, the outputs were compared with the literature.
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