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Influence of tempering to dimension of two-component polycarbonate molding
Svobodová, Hana ; Dočekalová, Julie (referee) ; Sedlák, Josef (advisor)
This bachelor thesis is focused on changing the dimensions of two-component polycarbonate holding during the tempering process. In the thesis there is a complete description of the production of the external lens for the automobile headlight. The experimental part is focused only on the part of the process, the tempering. The subject of the experiment is to determine the effect of the temperature in the tempering furnace and the effect of the used slats on the dimensions of the polycarbonate molding. 3D measurements are used to evaluace dimensionality. The influence of the slats is examined with free types of slats.
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Corrosion resistance of PA and PC components
Mikel, David ; Pospíšil, Ladislav (referee) ; Jančář, Josef (advisor)
The influence of two lubricating and cleaning agents and diesel fuel on environmental stress cracking of polyamide reinforced by glass fibers and polycarbonate was studied in this master thesis. Testing of environmental stress cracking was performed by the method of critical bending deformation. Bergen elliptical strain jig was used for testing. The test liquids caused varying levels of environmental stress cracking of amorphous polycarbonate, but they did not cause environmental stress cracking of glass fiber reinforced polyamide. The test method used allows testing the resistance of both materials against environmental stress cracking of any liquid. The results can be used to design products that are expected to be exposed to corrosive liquids. Quantification of the influence of stress free corrosion on the static and impact properties of polycarbonate and glass fiber reinforced polyamide was performed by accelerated test. Specimens were exposed to test liquid and an elevated temperature of 70 °C. The mechanical properties of the tested materials were significantly affected by elevated temperature exposure. The yield strength of the polycarbonate has increased and the toughness has decreased due to physical aging. The tensile strength of glass fiber reinforced polyamide has increased due to a decrease of the moisture content of the material.
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Elimination of internal stress in the polycarbonate moldings
Selucký, Jaroslav ; Hrbáček, Jan (referee) ; Chladil, Josef (advisor)
This diploma theses raises the issue of internal tension in two-component outer lense, which are made by injection of polycarbonate. The theses gives a more detail view on treatment of the lenses in heating ovens. Heating ovens have been used for decreasing the internal tension in lenses. The subject of the experiment is to determine the influences of the adjustable parameters of the heating oven. The Experiment will be taken by DoE method. The influence of the adjustable parameters is researched and compared among the two types of outer lense with different type of design.
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Effects of structural and processing parameters on th eproperties of polymer nanocomposites
Zárybnická, Klára ; Žídek, Jan (referee) ; Jančář, Josef (advisor)
The work deals mainly with preparation protocol of nanocomposites. The task of this work is to study structural and procedural parameteres that control the dispersion of nanoparticles in polymer solution to be able to prepare desired spatial organization of nanoparticles. The work resolves the effect of various components such as polymer matrices, nanoparticles and solvent, in which matrices and nanoparticles are blended. Used components control final dispersion state of nanoparticles and it influences also properties of investigated materials such as glass transition temperature, stiffness and rheological properties.
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Design of manufacturing technology for plastic mount carbon
Fojtík, Jakub ; Mořkovský, Václav (referee) ; Kandus, Bohumil (advisor)
This master thesis deals with design of injection moulding technology for plastic holder of carbon brushes made of polycarbonate labelled Lexan 945A. The injection is performed into injection mould with hot runner system. Initially there is general study related to plastics and injection moulding technology. Further the study continues with injection moulds with hot runners and ends with computer analysis of injection moulding process. The designed injection mould for production of plastic holders is three-plate, double cavity mould with four hot nozzles and one parting plane, where one of the plates serves for mounting of the hot runner system inside the mould. This work contains part of the drawing documentation and item list of the injection mould. The selected injection moulding machine is Arburg Allrounder 370 U labelled 700-290 according to EUROMAP.
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Replacement of headlamp parts screw fixation by a plastic nail
Lysa, Bohuslav ; Píška, Miroslav (referee) ; Polzer, Aleš (advisor)
The master thesis covers several issues linked to a substitution of headlamp screw fixation by a plastic nail. The thesis includes an analysis of the headlamp technology, including description of the prescribed durability tests. On the basis of the analysis some new designs of plastic nails are proposed, consistent with characteristics of plastic materials. Selected outcomes of the analysis have been tested as prototypes and verified with Finite Elements Method in SimDesigner including 3D modeling capabilities provided by the Catia V5. The feasibility study regarding a casting form of the new design of plastic nails and technical economic valuation for contingent assembly mounting is included in the thesis.
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Polyethylenterepthalate Copper Plating for Conductive Structures Realisation
Chmela, Ondřej ; Zatloukal, Miroslav (referee) ; Starý, Jiří (advisor)
The content of this master’s thesis are methods of pretreatment and coating of the surface of PET to produce conductive copper structure and quality control. Thesis also includes theoretical analysis of these methods. Physical and chemical techniques of surface pretreatment methods are discussed in the theoretical part as well as methods making surface of substrate conductive, the subsequent galvanic copper plating and quality control of coating and testing of the adhesion between layers. The experimental part focuses on two methods of the polymer material surface pretreatments. The properties of these pretreatments were evaluated by using the atomic force microscopy and detection of surface energy by wetting and contact angle measurements. The surface is making conductive with cathode sputtering and electrochemical coating of copper. Adhesion of layers is tested mainly with scratch test and other methods. The results of these sub-operations are used for the realization of multi-layer conductive structures.
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Polymer nanocomposites for interior car body parts
Miškolci, Michal ; Bálková, Radka (referee) ; Jančář, Josef (advisor)
This bachelor’s thesis is interested in the problem of scratch resistance of interior car body parts. In this thesis, the solution is seen in using polycarbonate – based nanocomposites. In theoretical part, a literature search of this theme was made. In experimental part, the samples based on polycarbonate were prepared, and their tensile modulus was tested, as one of the main parameter affecting the scratch resistance.
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Design and production of a plastic komponent
ČÍŽEK, Václav
The theoretical part is focused on evaluation of chosen ?essential? plastics used in the car industry. The principles of construction and proportioning of plastic components, basic conception of injection moulding and measuration follow. Another section of the theoretical part presents a summary of possible CAD systems, which are used. The practical part is focused on a particular plastic moulding. It includes the main description of a component with its material choice in dependence on the component function. Another section contains evaluation of the component complexity from the viewpoint of moulding, and a possible substitution of constructions, which could be productively simpler, is shown. The whole thesis is completed for better lucidity by pictures, drawings, and mechanical drawings.
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