National Repository of Grey Literature 41 records found  beginprevious31 - 40next  jump to record: Search took 0.01 seconds. 
Testing of selected material properties for 3D printing
Čáslavský, František ; Mačák, Martin (referee) ; Vyroubal, Petr (advisor)
This thesis deals with 3D printing, materials used for 3D printing, testing of the materials and learning their real parameters. Goal of the thesis is comparing selected materials, executing series of mechanical test and selecting suitable material for printing high-quality plastic parts for use in automobiles, especially for reproduction of parts that are no longer made for oldtimers and for use in motorsport.
Experimental comparison of recycled and non-recycled filament of ABS plastic
Grygar, Filip ; Krčma, Martin (referee) ; Koutecký, Tomáš (advisor)
Plastic waste which arises from 3D print could be recycled. One of the most used materials is ABS with which this degree work deals. During recycling of ABS mechanical qualities rapidly deteriorate which is compensated by adding non-recycled ABS. This degree work dealt with a ratio of 25% of recycled to 75% of non-recycled material which is a ratio not have been tested so far, and most likely represents a boundary ratio when recycling still makes sense. Unfortunately, it was not possible to extrude from a recycled material a filament of high-quality enough which could be used for problem-free print. It was influenced by non-homogeneity of crushed components and the construction of an extruder. For improving the characteristics a more complex extruder would be needed, with a bigger screw diameter or with two screws, and also a cooling system with more zones. Professional grinders with screens would have to be used for improving homogeneity of the material. The melt flow index of the liquid alloy and the testing of the filament itself showed that this way is practicable and such a recycling is realistic.
Experimental comparison of filament produced from recycled and regular PET
Tomčová, Renata ; Vaverka, Ondřej (referee) ; Koutecký, Tomáš (advisor)
This bachelor thesis deals with the experimental comparison of filament made from recycled and common PET. Filament was made from commercial granulate of PET, PET-G and from recycled PET bottles. Sample pieces were printed using FDM technology from these filaments and then the sample pieces were tested using a tensile test. The sample pieces made from recycled PET filament had one third worse tensile strength than the sample pieces made from common PET and PET-G filaments. Thanks to this bachelor thesis it is possible to decide, if it is worthy producing filament from recycled PET bottles even at the cost of reducing the mechanical properties of final products.
Creating a 3D model and its realization on a 3D printer
LIŠKOVÁ, Markéta
The aim of this bachelor work is the creation of a 3D model and its realization. As the product of the 3D printing demonstration is chosen a bike bag for money and keys, which is placed under a seat on a seatpost. The theoretical part of the bachelor work presents a brief history about 3D printing, 3D printing technologies, editors for creating models and basic materials. The model is designed in an online editor TinkerCad. The printing is done by Fused Deposition Modeling (FDM) technology on the Original Prusa i3 MK3 printer. A part of the work is a simple handbook, which describes on a trolley coin with the JCU logo, how to create your own model and how to print it on the FDM printer.
The thermal conductivity of non-standard materials for HVAC
Běťák, Karel ; Rubinová, Olga (referee) ; Uher, Pavel (advisor)
The thesis is focused on the determination of the thermal conductivity coefficient on the group of thermoplastics used for 3D printing (PLA, ABS, PETG). The thesis describes the materials used for 3D printing and the design of air conditioning for the grocery store. A stationary method was used for the solution. The heat flux passing through the sample was measured and the thermal conductivity coefficient was calculated. By the chosen method, we determined the coefficient is = 0,11-0,13 W/(m·K). Comparison with the available results of other methods and authors has shown that the resulting coefficient is lower. Based on the data, it is possible to compare the thermal properties of 3D printing materials.
Remote control of 3D printer
Kajzr, Miroslav ; Jaššo, Kamil (referee) ; Vyroubal, Petr (advisor)
The essence of this work is to summarize the knowledge about 3D printing, especially with FDM technologies. Create an overview of used FDM printing materials, identify their advantages and disadvantages, technical parameters and usability. Another purpose of the thesis is to examine the print quality and its problems and specify types of surface finishes for selected materials. The content also includes remote control and monitoring of the 3D print process using the Raspberry Pi microcomputer and the print server named Octoprint.
Design and properties of low-frequency amplifier with vacuum valves
Piroha, Ladislav ; Musil, Vladislav (referee) ; Šandera, Josef (advisor)
The purpose of the bachelor’s thesis is explanation of theory and construction of low frequency tube audio amplifier with UV meter. Main focus is on history and development of vacuum circuits from its early beginning, on electrical parameters and applied physical principles. Explanation of operating characteristics of amplifier classes and comparison of vacuum tube sound acoustic performance against transistor amplifier one. Finally, there is build description of single ended amplifier class A.
Design and implementation of 3D printer with network printing support
Špringer, Radek ; Hošek, Jiří (referee) ; Krajsa, Ondřej (advisor)
The goal of this thesis is to design a 3D printer type delta. To describe 3D printing technologies used by this printer, basic printer features and commercially available material used at the print and its comparison. To define all hardware components, which are necessary for construction of the 3D printer type delta. To create a proposal and construct an expansion board to which all hardware components of the printer will be connected. To optimize the print space heating and cooling of the printout. To extend the 3D printer with a Web server, which will ensure the network printing possibility.
Graphic VFD display control using Atmel microprocessors
Hrubý, Michal ; Pust, Radim (referee) ; Hanák, Pavel (advisor)
This thesis discusses VFD displays; the operating principles, construction, applications, types of displayable information, power supply and control. The thesis explains means of communication and control of modern VFD modules with exemples code. The thesis also includes a selection of a particular graphic VFD display in accordance with the given requirements and design of power supply and control circuits on a printed circuit board.
Multi-filament yarns testing for textile-reinforced concrete
Kaděrová, Jana ; Seitl,, Stanislav (referee) ; Vořechovský, Miroslav (advisor)
The scope of the presented master thesis was the experimental study of multi-filament yarns made of AR-glass and used for textile-reinforced concrete. The behavior under the tensile loading was investigated by laboratory tests. A high number of yarn specimens (over 300) of six different lengths (from 1 cm to 74 cm) was tested to obtain statistically significant data which were subsequently corrected and statistically processed. The numerical model of the multi-filament bundle was studied and applied for prediction of the yarn performance and for later results interpretation. The model of n parallel filaments describes the behavior of a bundle with varying parameters representing different sources of disorder of the response and provides the qualitative information about the influence of their randomization on the overall bundle response. The aim of the carried experiment was to validate the model presumptions and to identify the model parameters to fit the real load-displacement curves. Unfortunately, due to unsuccessful correction of measured displacements devalued by additional non-linear contribution of the unstiff experiment device the load-displacement diagrams were not applicable to model parameters identification. The statistical evaluation was carried only for the maximal load values and the effect of the specimen size (length) on its strength was demonstrated. The size effect curve did not exclude the existence of spatial correlation of material mechanical properties modifying the classical statistical Weibull theory.

National Repository of Grey Literature : 41 records found   beginprevious31 - 40next  jump to record:
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