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Influence of Process Parameters and Heat Treatment on the Structure and Properties of Cold Spray Method
Lindner, Patrik ; Řehořek, Lukáš (referee) ; Hutařová, Simona (advisor)
The bachelor thesis is a research of the state of knowledge focused on Cold spray technology and process parameters affecting the properties of coating, such as pressure, temperature, nozzle speed, sequence of individual layers, size of powder and others. This technology uses the kinetic energy of the impact of particles on the substrate. The main advantage of this method is possibility of forming a coating of large thicknesses (in millimeters) without oxides, with relatively low porosity and favourable mechanical properties. Aim of this work is to get acquainted with the Cold spray technology and the influence of process parameters on the quality of the spray. The influence of process parameters on properties is also demonstrated by own experimental results.
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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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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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ELECTRON BEAM WELDING OF HETEROGENEOUS WELDS OF Ti/Al ALLOYS
Havlík, Petr ; Dřímal, Daniel (referee) ; Schwarz,, Drahomír (referee) ; Foret, Rudolf (advisor)
The problematics of weldability of heterogeneous welds of aluminium and titanium alloys produced by electron beam welding is discussed in this work. Homogenous welds of selected alloys were analyzed in the first stage. Welding of these materials relates to formation of intermetallic phases at the interface of base materials due to differences in physical, chemical and metallurgical properties of base materials. One of the prerequisites for producing high quality weld joints is to find optimal process parameters. The influence of selected process parameters to integrity, structure and mechanical properties of heterogeneous Al/Ti joints is evaluated.
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