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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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Mechanical properties of materials prepared by SLM process
Nopová, Klára ; Štěpánek, Roman (referee) ; Pantělejev, Libor (advisor)
The final thesis determined the properties of alloys formed from mixtures of powders processed by the SLM method. Powders of alloy AlSi12 and EN AW 2618 were fused in the proportion 75 wt. % AlSi12 + 25 wt. % 2618, 50 wt. % AlSi12 + 50 wt. % 2618 and 25 wt. % AlSi12 + 75 wt. % 2618. Metallographic analysis, EBSD analysis and line EDS microanalysis were made on the samples. Tensile test at room temperature and hardness were carried out to determine the mechanical properties. Fractographic analysis was performed after tensile test.
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Processing of Al-Sc aluminum alloy using SLM technology
Skulina, Daniel ; Náhlík, Luboš (referee) ; Koutný, Daniel (advisor)
Master's thesis deals with the experimental determination of process parameters reaching densities >99 % for scandium modified aluminium alloy (Scalmalloy®) processed by SLM. The alloy achieves higher mechanical properties than the AlSi10Mg aluminum alloy commonly used. The theoretical part deals mainly with the results of Scalmalloy® alloys. Experimental bodies, testing methodology and evaluation method were designed on the basis of the theoretical parts,. The practical part is divided into four main stages: experimental determination of process parameters, a description of the effect of the parameters used on the relative density achieved, examination of the influence of process parameters on surface quality and mechanical testing. The mechanical properties were determined for the best parameters.
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Mechanical and microstructural characteristics of materials produced by SLM method
Hradil, David ; Jan, Vít (referee) ; Pantělejev, Libor (advisor)
The master's diploma thesis deals with the mechanical and structural characteristics of aluminium-base alloy 2000 series, produced by selective laser melting (SLM). The experimental part of the thesis deal with selection of SLM processing parameters, influence of scanning strategy and evaluation of mechanical and structural characteristics of fabricated materials. Mechanical characteristics were evaluated based on results of tensile tests and microhardness measurement. Structural characteristics of materials produced by SLM were evaluated using metallographic analysis.
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Design of oxygen filter for 3D metal printer
Ondra, Martin ; Paloušek, David (referee) ; Suchý, Jan (advisor)
In medical branches alloys on the basis of titanium are commonly used, however, in some of the medical applications it emerged that the usage of alloys on the basis of magnesium is more convenient, for example in orthopaedic surgery for the implant fabrication. Managing of processing of magnesium using the technology Selective Laser Melting would enable to produce complex structures supporting the production of cells and recovery of bones. One of the problems when processing the alloys on the basis of magnesium is the production of residual oxygen. This problem can be solved with the usage of an oxygen filter that is integrated in the circuit of inert atmosphere. This bachelor´s work deals with the construction of this filter for 3D metal printer SLM Solutions 280HL v1.0. This device enables to filter up to 123 m3/h of the gas with the output purity 100 ppt (1,0 × 10-8 %). The device separates oxygen continuously during the whole manufacturing process. The construction of the device enables the attachment to other SLM Solutions company machines.
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Process parameters development for copper thin walls manufacturing via 3D printing
Klimek, Ľubomír ; Hutař, Pavel (referee) ; Paloušek, David (advisor)
In the work is used the processing of metallic material by the method of Selective Laser Melting. The main objective is to verify and describe the influence of the individual process parameters entering the production process when processing the alloy Cu7.2Ni1.8Si1Cr with SLM. This alloy contains 90 % copper. The first theoretical part of the thesis describes so far processed copper alloys with a high content of copper using the method of Selective Laser Melting. The practical part then deals with the specification of the main process parameters, which are optimized in the next part of the work solution. On the basis of the information obtained experimental bodies have been created, which will be tested and analyzed in several steps. The work focuses on thin-walled samples, which have a perspective use in the creation of highefficiency heat exchangers. The main results that the work deals with are the relative density and mechanical properties of the material. Also, great emphasis is placed on the resulting surface quality
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Mechanical properties of materials prepared by SLM process
Doubrava, Marek ; Válka, Libor (referee) ; Pantělejev, Libor (advisor)
The diploma thesis deals with the selection of process parameters used for manufacturing of high-strenth materials using SLM technology. The feedstock material was powder with a chemical composition according to standard DIN X3NiCoMoTi 18-9-5. Influence of change in process parameters on mechanical properties was examined by hardness tests and tensile tests. Metallographic and fractographic analysis were conducted with an aim to understand mechanisms of failure present in this type of material. Selection of optimal process parameters was based on the analysis of mechanical properties of manufactured samples. Possible future steps related to the improvement of the process were proposed. Results of this experiment were compared with literature regarding parts produced by SLM technology and conventional methods.
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Microstructure of AlSi9Cu3 alluminium alloy processed by SLM technology
Rychnovský, Daniel ; Nopová, Klára (referee) ; Vašáková, Kristýna (advisor)
This bachelor thesis deals with microstructure of aluminium alloy AlSi9Cu3 produce by SLM process. In theoretical part the SLM process is shown. In following topic, the defects which can occur during SLM are mentioned. In the end of the theoretical part the materials made by SLM and materials made by conventional method (casting) are compared. In experimental part the porosity of the samples made by SLM is examined by image analysis. The examine of the microstructure is also included. Results are discussed with literature.
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Mechanical properties of materials prepared by SLM process
Vašáková, Kristýna ; Řehořek, Lukáš (referee) ; Pantělejev, Libor (advisor)
This diploma thesis deals with properties of multi-materials interface composed of pure iron and Cu7Ni2Si1Cr alloy produced by SLM process. The theoretical part of thesis is focused on selective laser melting technology, and on description of defects connected with the production of SLM parts. Furthermore, one section deals with the production of multi-materials prepared by the SLM process. The experimental part of this thesis deals with selections of the SLM process parameters appropriate for bulk samples preparation. Mechanical properties were determined by the tensile tests at room temperature. Metallographic and fractographic analyses were performed for evaluation of the microstructure and description of the fracture mechanisms.
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Model of geometry of micro-lattice structures for finite element method
Javorský, Dominik ; Maňas, Pavel (referee) ; Červinek, Ondřej (advisor)
The growing availability of additive manufacturing technology, such as SLM, enables the creation of innovative structural designs. An example of these are complex lattice structures which are used because of their excellent mechanical properties relative to weight. One significant challenge lies in production tolerances. These are not crucial for the majority of components. However, when dealing with lattice structures and their thin-walled geometry, manufacturing tolerances lead to substantial deviations in mechanical properties. The process of designing such structures and achieving results comparable to the experiment requires the use of non-standard methods. These methods are time-consuming and costly for obtaining real geometry. The real geometry is then used for numerical simulations based on the FEM principle. This thesis focuses on the impact of geometric imperfections occurring in BCC-type structures made of stainless steel 316L. During the solution, the real geometry was obtained through optical digitization using the ATOS Triple Scan scanner. Dynamic drop-weight tests were also conducted, and the obtained results were used to modify the geometry model in combination with the acquired real geometry. The aim was to minimize the deviation between experimental and numerical simulation results below 5%. The knowledge gained from this process was then applied in simulations investigating the impact of geometric imperfections. Deviations up to 30% were observed in simulations investigating the impact of geometric imperfections. These deviations can be minimized by incorporating the knowledge of real geometry into the design. The results also help determine the diameter range within which including geometric imperfections in the design is irrelevant. Furthermore, a significant impact of the node geometry on the results of numerical simulations was observed. This knowledge brought the values closer to the experimental data. Another important contribution of this work is the simplified geometry model. This model will enable the study of the impact of additional imperfections in a range that was previously unattainable.
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