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Study of inorganic matrix composites for FRP
Svora, Petr ; Rovnaník, Pavel (referee) ; Puliš,, Pavel (referee) ; Šubrt,, Jan (referee) ; Bodnárová, Lenka (advisor)
During a whole period of time which fibre-reinforced polymers have been used in the building industry, in dominating bonding agent has been the organic resins. There is no doubt about their advantages, but at the same time, they have two weaknesses: they are not fire resistant and they have no resistance to high temperature. Those are the reasons why the research on alternative materials which could replace organic matrix has been undertaken. The goal of the work is to maintain mechanical properties of fibre-reinforced polymer with organic matrix. Of course, an emphasis is placed to fulfilling ecological standards which are required from ecological material. An aluminosilicate inorganic matrix can meet them all. It is non-flammable, does not produce any toxic matter in contact with fire and the energy consumption during production process is lower than in case of the organic matrix. This work includes study and analysis of selected raw materials as well as their influence and impact on final reaction products which are created in inorganic matrix. A part of this work is also a design of the inorganic matrix recipe.
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Phosphate binders
Kalina, Lukáš ; Ptáček, Petr (referee) ; Šoukal, František (advisor)
The work deals with the preparation and study of polyphosphate composites. Aluminum phosphates provide some unusual properties like high-heat resistance in terms of inorganic binders. The addition of chromium in the form of Cr2O3 or directly the bond with the aluminum-chromium-phosphate can improve the properties of this binder. Highly viscous Al2Cr(H2PO4)9 and Al3Cr(H2PO4)12 binders were prepared by dissolving Al(OH)3 and CrO3 in 85% phosphoric acid, and mixed with Al2O3 and Cr2O3 fillers. The composites were cured in the furnace at 150 °C for 24 h under pressure of 10 MPa. During the annealing at temperatures up to 1 500 °C changes in chemical structure of the cured composites were observed, leading to the understanding of the creation of crystalline phases and their eventual changes. The characterization of binders was mainly based on FT-IR, EDAX, TG-DTA and optical microscopy analyses.
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Preparation and characterization of highly filled composite materials for dental applications
Gavroňová, Ivana ; Bystřický, Zdeněk (referee) ; Poláček, Petr (advisor)
Master thesis deals with highly filled particulate composite materials for dental applications. In the practical part, the dimetacrylate matrix was filled with a mixture of particles of different types and different sizes to achieve the maximum possible packing. Moreover, filler content and the influence of filler on composite material was studied. Hydrolytic stability was also tested on composite materials. The methods used to characterize composite materials were bending test, thermogravimetric analysis (TGA), differential scanning photocalorimetry (DPC), dynamic-mechanical analysis (DMA) and scanning electron microscopy (SEM). Curing of the matrix was characterized by the degree of conversion, the heat of polymerization and the polymerization rate. Furthermore the polymerization shrinkage was measured. The glass transition temperature, the dynamic modulus at 40 °C and 100 °C, the modulus of elasticity, the strength, the critical value of the stress factor and the critical energy release rate were found in the tested samples.
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Composite materials used in the manufacture of cars
Rendek, Marek ; Juliš, Martin (referee) ; Němec, Karel (advisor)
Bachelor’s thesis deals with various types of composites used in the spheres of automotive industry. In the first section, it’s focused on the introduction to issues of composite materials, methods of production, their advantages and disadvantages. The second part of thesis focuses on specific applications in the automotive industry. In the final part there is a future evaluation and an overall view of the composite materials in the automotive field.
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Analysis of composite sandwich panel under conditions simulating placement on a rocket carrier
Král, Martin ; Horníková, Jana (referee) ; Majer, Zdeněk (advisor)
This work deals with composite sandwich panels, which are currently used as supporting structures for satellites. This type of panel contains an aluminum honeycomb core and two thin laminate coatings, reinforced with carbon fibers. Laminate sandwich panel coatings offer an alternative to conventional aluminum coatings, which is advantageous mainly due to the reduction of weight and increase of the flexural stiffness of the panels. The work is a parametric study of mechanical properties for several variants of the coating of sandwich panels. These are laminate coatings, differing in the orientation of the fibers in the individual layers, as well as an aluminum alloy coating. The study is divided into two parts. The first part examines the deformation-stress response of a sandwich panel, which is simply supported at the edges and loaded with pressure. The response calculation is performed using FEM and verified by the method of sum of an infinite series. The second part investigates the deformation-stress response of the joint, (node) of two sandwich panels, which is loaded by random vibrations, aimed at simulating the mechanical environment of the rocket carrier during the takeoff of the launch vehicle. The response is calculated using FEM and verified by an experiment on a vibrating stool for a selected variant of the laminate coating of sandwich panels. The results of the work can be used for the design of baffle of the X-ray imaging device (SXI), which is part of the equipment of the space satellite of the SMILE project.
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Composites Application in Automotive Industry
Bačovský, Marek ; Dundálek, Radim (referee) ; Ramík, Pavel (advisor)
This bachelor´s thesis deals with the use of composites in the automotive industry. The first part of the thesis processes overview of the basic properties of composites, their structure, characteristics, advantages and disadvantages. The second part focuses on their application in series manufacture and in racing cars, incl. Formula Student. The final section provides a view into the future and the overall evaluation of composite materials.
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Optimisation of cement-bonded particleboard matrix composition by using alternative raw material sources
Roháček, Lukáš ; Vacula, Miroslav (referee) ; Bydžovský, Jiří (advisor)
The diploma thesis deals with possibility of utilization raw materials from alternative sources for production of cement-bonded particleboards. In theoretical part the possibilities of modifying composition of cement-bonded slabs with emphasis on their matrix are discussed in detail. On basis of the findings and their evaluation, waste from the formatting of cement-bonded particleboards, micronized limestone, heat sink and high temperature fly ash were selected to the composition modification. The mentioned raw materials were analyzed and subsequently tested as substitutes for the matrix of cement-bonded particleboards in the experimental part. The properties of the proposed materials were tested even in the longer term, including the microstructure.
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Application of thermoplastic composite materials on aircraft structures
Vráblíková, Lucie ; Symonov, Volodymyr (referee) ; Klement, Josef (advisor)
This bachelor thesis deals with thermoplastic composite materials in aircraft industry. The aims of the thesis are divided into three parts. The first part contains an overview of the basic properties of fibre-reinforced thermoplastics, their structure and characteristics. In the second part, there are introduced different technologies of manufacturing thermoplastics. The last part deals with applications of thermoplastic composite materials in aircraft industry.
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Design of the Timber-Concrete Composite Ceiling Structure
Válek, Jakub ; Horák, David (referee) ; Švaříčková, Ivana (advisor)
The reconstruction of existing houses is currently a frequent issue. This work deals with the possibilities of reinforcing wooden ceilings with the focus on ceiling reinforcement using an over concrete slab. This suggested ceiling reconstruction work is desirable from the point of view of the rigidity of the object in the horizontal direction. The work includes the proposition for the composite, according to various norms and their comparison regarding the economic side of the design. The work further provides a description of the experiment, its preliminary results and its comparison with the theoretical calculation.
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