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Design of mold segment for molding tires manufactured using Selective Laser Melting
Kvaššay, Adrián ; Maňas, Pavel (referee) ; Rapant, Martin (advisor)
This diploma thesis deals with development and design modifications of tire mould segment which will be batch produced by additive technology Selective Laser Melting. Material for its production is maraging steel 1.2709. Lattice structure was used inside the segment construction. The geometry of the lattice cell was chose based on two main factors – eliminating production costs and providing sufficient stiffness. Strength of the segment was calculated by FEM. The functional sample was made and its distortion was analyzed by optical digitalization.
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Multipurpose Hall Jaroměřice nad Rokytnou
Mikulincová, Denisa ; Teplý, Vladimír (referee) ; Odvárka, Antonín (advisor) ; Matějka, Libor (advisor)
The assignment is the design of a multi-purpose hall in Jaroměřice nad Rokytnou. Building is designed on the site of a former city gym and should serve in a similar way. The multi-purpose hall provides space for sports activities and cultural events. The hall also includes areas for preparing snacks and smaller halls. The building is designed as barrier-free. The building has a longitudinal shape, respects the urban layout of the original structure. The roof of the hall is partly designed as a residential. The building has access to playgrounds and tennis courts.
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The developement of SLM laser strategy for lattice structure fabrication
Jaroš, Jan ; Dočekalová, Kateřina (referee) ; Vrána, Radek (advisor)
Additive technology (AT) is increasingly used to design unique parts, mainly due to the ability to produce complex structures such as lattice structures. However, this also includes the need to modify the process parameters or the production strategy of the AT, which is usually set to produce volume geometry. Using samples corresponding to the geometries of the lattice structures, the exact input values were measured, which were used to design the SLM (Selective laser melting) production process using a contour strategy. Thanks to this, vertical and angled (35.26°) struts with low porosity (up to 0.2 %), low surface roughness and high dimensional accuracy were produced. Porosity was measured on µCT, surface roughness and dimensional accuracy were measured on STL data. The results show that if the parameters of the SLM process are set correctly, it is possible to produce struts with low porosity and surface roughness using different combinations of laser power and scanning speed. The above findings were used in the creation of script that allow the selection of suitable process parameters to produce lattice structures.
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Lattice Topology Optimization in ANSYS software
Černák, Martin ; Vaverka, Ondřej (referee) ; Vrána, Radek (advisor)
ANSYS is one of the first commercially available software which allows to make topology optimization of lattice structures. In this bachelor’s thesis optimization workflow, calibration of numerical model, validation of numerical results and revelation of influence of basic parameters involved in computation – cell type, minimum and maximum relative density, cell size and used discretization, are showed. Optimised part was compared by means of FEM and homogenization with available experimental data. Subsequently, influence of basic parameters was evaluated. It was shown that optimized structure is stiffer than benchmark and influence of basic parameters for mechanical response and computational complexity was introduced. Simultaneously, it was shown that homogenization overestimated mechanical response. The findings of bachelor’s thesis validate computational model in program ANSYS and can be used for more effective making of optimization models.
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Development of the Impact Energy Absorber Made by Metal 3D Printing
Kraicinger, Vít ; Malý, Martin (referee) ; Vrána, Radek (advisor)
Today, variously profiled parts are mainly used for energy absorption. For special cases, precise components are designed, as in the case of Formula Student, where a deformation article with a honeycomb structure is used. This bachelor thesis is focused on the design of an impact energy absorber made by SLM technology and lattice structures. For the design itself, a comprehensive overview of current knowledge in the field of deformation zones, energy absorbers and researches dealing with energy absorption was created. Based on the study, the most suitable material to produce AlSi10Mg was selected. Subsequently, the appropriate type of grid (BCC) and all parameters of the lattice structure were determined. Two energy absorbers with different struts diameters (0.4 mm and 0.8 mm) and different grid sizes (4 mm and 8 mm) were modeled for the selected parameters. At the end of the work are two simplified calculations that show the predicted final values of the proposed absorbers and the stiffness of the layers of the lattice structure with graded density.
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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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Numerical model of lattice structure under dynamic loading made by Selective Laser Melting technology
Červinek, Ondřej ; Maňas, Pavel (referee) ; Vrána, Radek (advisor)
For the purpose of mechanical impact energy absorption in the transport industry are mainly used special profile absorbers. For highly specialized applications is required to use components that are designed for specific kind of deformation. Example of these parts are industrial-made metal foams or micro-lattice structures produced by SLM technology. This paper focuses on low-velocity dynamic loading prediction of BCC micro-lattice structure made of aluminum alloy AlSi10Mg by SLM technology (SLM 280HL). For this purpose dynamic FEM simulaton of the micro-lattice structure was developed, supplemented by model of BCC structure material obtained from mechanical testing. Real geometry of tested samples obtained from optical measurement (Atos Triple Scan III) was further implemented in the numerical model. Dynamic BCC structure load experiment was performed on a drop-weight tester. Behavior of structured material in drop-weight test was described by the course of deformation and reaction forces over time. Comparable results were obtained for flat loading of dynamic FEM simulation and experiment. Inclusion of production phenomena in simulation led to increased accuracy and compliance with experiment. Tool for testing the effect of geometry change on mechanical properties was created. To achieve more accurate results with puncture load, it is necessary to modify the material model with real material deformation at test sample failure.
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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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