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Biocomposites based on polyhydroxybutyrate for 3D printing
Horálek, Matyáš ; Tocháček, Jiří (referee) ; Přikryl, Radek (advisor)
The submitted diploma thesis deals with preparation and characterization of biocomposite based on poly-3-hydroxybutyrate. Biocomposites were fabricated with respect to later use in 3D printing. The methodology for testing different kinds of materials and their suitability for 3D printing as well as evaluation of mechanical and thermal properties was established. The first part of this work was focused on the experiments with print temperature and the material flow rate and its influence on the look of 3D printed object and on the material tendency to warp during 3D printing. The design of the experiment method was used for the analyzing of obtained data. It was proven that the amount of kaolin and tributyl citrate has positive influence in reducing warping. By optimization of the biocomposite recipe it was achieved improvement in tensile modulus of elasticticity, ductility, tensile strength, notched and unnotched toughness.
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Modern Materials for Automotive Industry
Vaníček, Jan ; Fojtášek, Jan (referee) ; Hejtmánek, Petr (advisor)
This work is focused on the description of conventional and unconventional materials that are used to build a car. Individual types of materials are sorted according to their application and characterized in terms of properties and real use. The end of each chapter is devoted to possible future trends.
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Mechanical response of glass fiber-reinforced polymer composite
Širjovová, Veronika ; Svěrák, Tomáš (referee) ; Čech, Vladimír (advisor)
The bachelor thesis is concerned with mechanical properties of glass fiber-reinforced polymer composites depending on the surface modification of fibers and the volume fraction of fibers in the composite. The tested samples in a form of composite beams were consisted of polyester matrix reinforced with long glass fibers without surface treatment (unsized) and with commercial sizing. Shear and flexural tests were employed to evaluate adhesion at the fiber-matrix interface. The theoretical part focuses on literary search for composites, their components (matrix, reinforcement, interphase) and methods of testing their mechanical properties. The experimental part describes used materials, procedures and methods. In the result part, an assessment of the influence of the given conditions on the shear and flexural strength of the composite is summarized.
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Mechanical properties of fiber reinforced composites for automotive applications
Bayer, Adam ; Žídek, Jan (referee) ; Jančář, Josef (advisor)
Bachelor’s thesis deals with studying mechanical features of fiber composites. As a matrix was chosen PMMA and as reinforcement was chosen glass fabric. Theoretical part sums up contemporary issues of polymer composites in automotive industry such as their production techniques and methods of impregnation. In experimental part were prepared samples by block polymerization of 30 % solution PMMA in monomer with initiator by 65° Celsius warmth oath, when was fabric directly unfolded in pre-polymer solution. On these samples were executed tensile tests by testing device Zwick and these samples were compared with results of theoreticaly calculated values.
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Surface treatment of a composite part
Bahenský, Štěpán ; Žák, Ladislav (referee) ; Kubíček, Jaroslav (advisor)
This diploma thesis focuses on composite materials and the possibility of their surface treatment with a focus on painting. The aim was to create a layer on the surface of the material that would serve as protection against UV radiation and subsequent degradation. The first theoretical part is devoted to the material composition. In the subsections, the different types of functional components of the composites are presented. Their possible applications as well as their advantages and disadvantages are described. In addition, the theoretical part is supplemented by the types of methods used for the production of composite materials and the subsequent surface preparation in order to improve the adhesion properties of the material to the paint. The second part, which was developed in cooperation with GDP Koral, s. r. o., deals with the chosen type of surface treatment for composite materials produced by the pultrusion method. The UV coating method was chosen, where the wet layer of the varnish is cured by UV radiation. Two sets of samples were created, which differ in both the method of varnish application and the parameters of the curing process. Mechanical tests were then performed on each sample to verify the resulting adhesion capability of the paint system. The practical part also includes the design of possible technologies for the implementation of the surface treatment in the production line. In the third part, a techno-economic evaluation is presented, which focuses on the cost comparison of standard painting and painting with UV varnishes. The final section contains a summary of the findings and an evaluation of the chosen type of coating with respect to the results of mechanical tests and the possibilities of application in a pultrusion production process.
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Design VUT 022 Aircraft with Jet Engine according to CS-22 Regulation
Matěják, Vladimír ; Popela, Robert (referee) ; Juračka, Jaroslav (advisor)
The diploma thesis deals with the design, load calculation and stress analysis of a composite wing construction of an airplane based on the construction of the airplane VUT 001 Marabu in order to fulfil conditions of CS-22 specifications. As a part of the thesis are basic mass, moment and aerodynamic characteristic of the airplane analyzed. Also the modification of the center part of the fuselage is designed in order to enable a jet engine instalation inside the construction.
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Modification of the filler in cement-bonded boards with alternative filamentous fillers
Dywor, Michal ; Vacula, Miroslav (referee) ; Bydžovský, Jiří (advisor)
The cement boards are commonly used as a filler fir or spruce chips-profit wood. The increasing demands for construction materials forcing technology to develop new types of composite materials using an alternative source of fillers. In this work in the context of theoretical knowledge about the specified fibers in composite systems are discussed properties of cement binder and filler for cement – bonded particleboards and alternative materials. The practical part describes the test methods designed recipes and then made boards of which were carved specimens intended for testing the properties of boards with alternative fillers.
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Manufacturing Process and Applications of Composite Materials for buses parts
Rusek, Jan ; Julišová, Martina (referee) ; Němec, Karel (advisor)
The aim of the bachelor’s thesis is the evaluation and demonstration of the usability of composite materials in the bus industry. The first chapter provides an overview of selected types of composite materials, basic classification, description of their parts and demonstrations of methods of production. The second part of the bachelor’s thesis is focused on the evaluation of the advantages and disadvantages of using composite materials. The last part is focused on the producion of the sample from fiberglass.
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Composite materials with silica matrix in the environment of high temperatures
Lisztwanová, Ewa ; Luňáček,, Martin (referee) ; Bydžovský, Jiří (advisor)
This thesis deals with the study and design of composite materials based on silica matrix suitable for extreme conditions, eg. for the repair of concrete structures with anticipated increased risk of fire. The theoretical part summarizes basic knowledge concerning the fire resistance of structures and the behavior of the composite system during extreme conditions. Theoretically oriented section also contains information on alkali-activated materials and their use in high temperature environments. Based on the evaluation of the theoretical part of the experiment were designed and tested different types of composite materials with increased content of raw materials from alternative sources. Laboratory research has been based on testing of basic physico-mechanical parameters including phase composition and microstructure of the proposed formulations before and after thermal exposure of 1200 ° C. Also considered was the effect of different cooling conditions.
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