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Development of process parameters for Selective Laser Melting technology for processing of aluminum alloy AlSi7
Zvoníček, Josef ; Dočekalová, Kateřina (referee) ; Koutný, Daniel (advisor)
The diploma thesis deals with the study of the influence of process parameters of AlSi7Mg0.6 aluminum alloy processing using the additive technology Selective Laser Melting. The main objective is to clarify the influence of the individual process parameters on the resulting porosity of the material and its mechanical properties. The thesis deals with the current state of aluminum alloy processing in this way. The actual material research of the work is carried out in successive experiments from the welding test to the volume test with subsequent verification of the mechanical properties of the material. Material evaluation in the whole work is material porosity, stability of individual welds, hardness of the material and its mechanical properties. The results are compared with the literature.
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Friction components produced by rapid prototyping
Pečenka, Tomáš ; Škaroupka, David (referee) ; Omasta, Milan (advisor)
The main aim of this bachelor thesis is to make an overview of use of additive technology for production of friction components. The first part is concerned on review of additive methods and type of materials. In the second section are situated applications of this technology for fabrication of friction components. The main goal of last part is research in area of tribology of parts manufactured by additive technology.
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Electrospinning of polyvinylidenfluoride based fibers
Hošek, František ; Šťastný, Přemysl (referee) ; Částková, Klára (advisor)
Electrospinning is one of the rapidly developing methods for obtaining fibers of very small thickness. There is a wide-scale use of nanofibers, and it has a great potential in many fields, such as in medicine, biology, chemistry, electronics, environmental protection, energy-harvesting, and other. Polyvinylidene fluoride (PVDF) appears to be a promising material for fiber production for its excellent mechanical and chemical properties. It is a chemically inert substance, very resistant to thermal stress. The aim of this bachelor thesis is the preparation of PVDF fibers by electrospinning and the study of the influence of three different surfactants on the spinnability of PVDF, on the arrangement and the shape of fibers which are formed during electrospinning. The effect of surfactant concentration (1 wt%; 0.5 wt%; 0.25 wt%) on the spinning process at electrical voltages of 25 kV and 50 kV was studied. The theoretical part describes the properties and the division of polymers and looks at polyvinylidene fluoride (PVDF) as a source material in more detail. Furthermore, the electrospinning method is described, including process conditions and external parameters influencing the process of obtaining fibers. The experimental part describes the preparation of samples by electrospinning and their characterization. Fiber thickness, its appearance, arrangement, and the occurrence of defects when using individual surfactants were evaluated. It was found that the used ionic surfactants affect the thickness of the fibers and their morphology. Homogeneous fibers with a predominant arrangement in one direction, without defects, were obtained.
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Additive manufacturing of spatial trusses from polymeric materials
Křivohlavý, Petr ; Němeček, Stanislav (referee) ; Škaroupka, David (advisor)
This thesis is focused on creating polymer lattice struts without any necessary support in full length using robotic 3D printing. The aim of the thesis is to find suitable process parameters and printing strategies with respect to the accuracy of the polymer struts. A statistical model of effects of individual process parameters has been produced to achieve stated objectives. The model enables finding optimal process parameters. The printing strategies for thus established process parameters are tested to increase the accuracy of the finished print and the quality of the bonds between individual struts. The accuracy assessment is executed using optical 3D metrology. The maximum deviation from the nominal shape 0.54mm has been accomplished using discovered process parameters and printing strategies.
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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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Microstructure of Mg alloys prepared by SLM process
Handl, Jiří ; Vašáková, Kristýna (referee) ; Nopová, Klára (advisor)
The main aim of this bachelor thesis was to research for theoretical part dealing with additive manufacturing and magnesium alloys focused on alloy AZ91D. The experimental work analyzed samples processed by Selective laser melting (SLM) technology with different process parameters. The porosity was measured on the individual samples and the microstructure of alloy AZ91D processed by SLM method was described. The results were linked to the process parameters used and, also to the available literature.
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The study of the influence of process parameters on the roughness of the cut for flame laser cutting of structural carbon steel
Macháč, Patrik ; Hála, Michal (referee) ; Mrňa, Libor (advisor)
This bachelor thesis deals with the cutting of material with laser in an oxidizing environment. It is divided into two parts, theoretical and practical. The theoretical part describes general methods for cutting materials, their advantages and disadvantages, further current industrial lasers are described, as well as the influence of parameters on cutting quality. In the experimental part has been processed the influence of process parameters on the quality of the cut and comparison with ISO 9013. Material used in the practical part is the structural carbon steel called S235JRG2, which was cut in the oxidizing environment. Based on the evaluation of surface, the price of lasser cutting of one meter was selected and then as th best option of settings process parameters for achieving good surface quality was selected. At the conclusions of the thesis there are compared changes in proces parameters and their evaluation
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Processing of high-strength aluminum alloy AlSi9Cu3 using selective laser melting technology
Suchý, Jan ; Hutař, Pavel (referee) ; Paloušek, David (advisor)
Method selective laser melting can produce metal parts by using 3D printing. This diploma thesis deals with the influence of process parameters on the workability of AlSi9Cu3 high-strength aluminum alloy using selective laser melting. The theoretical part deals with relations between process parameters and identifies phenomena occurring during the processing of metals by this technology. It also deals with conventionally manufactured aluminum alloy AlSi9Cu3. In the work, material research is performed from single tracks tests, porosity tests with different process parameters and mechanical testing. Here are showing the trends of porosity change at scanning speed, laser power, individual laser stop distance, bulk energy, and powder quality. The workability of the material can be judged by the degree of relative density achieved. Simultaneously the values of the achieved mechanical properties of the selected process parameters are presented. The data obtained are analyzed and compared with literature.
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Experimental chamber for testing of special materials using SLM technology
Malý, Martin ; Dočkal, Aleš (referee) ; Koutný, Daniel (advisor)
The thesis deals with the influence of process temperature and pressure on 3D printing using Selective Laser Melting. The aim of the thesis is the design, manufacture and testing of the experimental chamber for SLM 280HL from company SLM Solutions. The main task of the experimental chamber is to increase the temperature of the preheating of the powder bed from the original 200 °C to at least at 400 °C. The device will be used to investigate the influence of high process temperature on the properties of printed materials. The thesis also deals with the design of the powder applicator for elevated temperatures.
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