This diploma thesis describes the design of composite structures rudder NG aircraft L410 based on the present Dural-weave construction. According to FAR 23 and circulars certification process is designed composite primary structure of the aircraft. It proposes the construction of a new rudder and selected materials design of a track composite materials. Program MSC Patran is this structure developed FEM model and using Nastran software Compost and the strength check.

In the doctoral thesis, the bi-layer ceramic bodies with core-shell geometry were prepared by thermoplastic co-extrusion method and for these composite bodies the mechanical properties were studied. For study of co-extrusion and mechanical properties were designed two composite systems. First system ZTA-A combined the dense core ZTA (zirconia-toughened alumina) and the dense shell Al2O3. Second system ZST-Z consisted of porous core and dense shell made from ZrO2 for both cases. In the thesis, the rheology of ceramic thermoplastic suspensions and their mutual influence during co-extrusion was studied. Subsequently, the debinding process and sintering were studied, and based on the optimization of all process steps were obtained defect-free bodies with core-shell geometry. The mechanical properties (elastic modulus, hardness and bending strength) were determined for sintered bodies. To estimate the stress path in the core shell bodies loaded in bending, the relationship considering different elastic moduli of the core and the shell was used. For bodies of ZTA-A system was increased the strength in comparison with monolithic bodies of the individual components. Thus, bodies with high surface hardness of shell from Al2O3 and moreover having high fracture strength in bending were obtained. The effective elastic modulus was decreased for bodies of ZST-Z system up to 25 % in comparison with the elastic modulus of dense monolithic samples. The same effective modulus of elasticity was possible to achieve with core-shell bodies while maintaining significantly higher fracture strength than monolithic porous bodies or pipes.

This work deals with the use of inorganic nanofibers in refractory castables. The thesis describes some of the results of previously conducted research on nanofibers. Also description of nanofibres, production and distribution. The experimental part is focused on studying the interaction of Al2O3 and SiO2 nanofibres with aluminate cement. The main subject of investigation is a dispersion of nanofibers using a surfactant and ultrasonication.

Reactive powder composites (RPC) have been recently a subject of many researches of modern concrete technology. This type of concrete is very fine and its behaviour exceeds the other types of concrete, therefore there are new possibilities of its use. The design and production of RPC is complex technology process which needs to gain new results in RPC research to get the best features regarding its higher price. This thesis is focused on design of reactive powder concrete (RPC200), which compressive strength is between 200 – 300 MPa. Next goal is to prove the influence of curing regimes like high temperature or pressure, and also check the possibilities of production of low cement reactive powder composite (LCRPC).

In the diploma thesis, an overview of the existing literature focused on the thermoplastic co-extrusion method was worked out and based on the findings, extrusion of the monolayer and homogenous bodies from ZrO2, Al2O3, ZTA a ATZ was studied. For thermoplastic extrusion the capillary rheometer was modified and the nozzle was designed and fabricated. Applying the co-extrusion method, homogenous ceramic rods and monolayer rods in structure core/layer: ZrO2/Al2O3, ZrO2/ATZ and ZTA/Al2O3 were fabricated. In monolayer rods, the interface quality and defects that originate during preparation were evaluated. Technological parameters and properties of homogenous rods were used to rate the structure and defects in monolayer rods. Monolayer rods ZrO2/ATZ and ZTA/Al2O3 with 2.5 mm diameter and 45 mm length (containing small defects) were prepared by thermoplastic co-extrusion.

Práce sleduje vliv velikosti částic na elastický modul a deformační chování za mezí kluzu. Bylo pozorováno, že jak elastická oblast, tak oblast za mezí kluzu ukazuje silnou závislost chování na velikosti částic. Cílem této práce je korelovat experimentální data a teoretické předpoklady které bylo odvozeny pro deformační chování v elastické oblasti a v oblasti za mezí kluzu pro amorfní polymery a konkrétně pro PMMA. Vše je motivováno propojit zatím oddělené oblasti kontinuální mikromechaniky a diskrétní nanomechaniky. Deformační chovaní PMMA plněného nano a mikro plnivem bylo pozorováno v elastické a plastické oblasti. Byl zkoumán vliv velikosti částic na velikost modulu a deformačního zpevnění. Mechanizmus vyztužení je interpretován s použitím teorie imobilizace řetězců, nanočástice mají silný vliv na molekulární dynamiku a kinetiku zapletenin. Mým příspěvkem k tomuto tématu je ukázat výraznou závislost na mechanizmu vyztužení v závislosti na velikosti částic. A to jak pod teplotou skelného přechodu tak nad teplotou skelného přechodu. Ačkoli pro velikost modulu byla publikována značná množství dat, která byla následně i interpretována, vliv částic na deformační zpevnění je poskrovnu. Během elastické deformace je primární struktura materiálu neměnná, jedná se o elastickou deformaci, za mezí kluzu již toto neplatí a primární struktura je zde nevratně poškozena. Bylo ukázáno, že obsah nano částic vede ke zvýšení meze kluzu a vyššímu deformačnímu zpevnění. Tento nárůst deformačního zpevnění je v korelaci s Guth-Gold rovnicí. Je předpokládáno, že nanočástice slouží jako další fyzikální zapleteniny a vedou k fyzikálně více zapletenému systému. Stejný efekt jako v elastické oblast tj. vliv velikosti částic na modul, byla pozorována i během deformačního zpevnění.

This master thesis shortly deals with properties and usage of the Resysta material. The main objective of this thesis is to determine a temperature influence on tensile strength of welded and glued joints made from the material Resysta, for an usage such as an outdoor furniture, temperature influence analysis of the joints and to present the results of the analysis obtained by measurements. Further objectives are: tensile strength experiment of material Resysta and to determine influence of placing the pieces in a desk in different directions. Results will serve as a basis for a specific firm; as a basis for deciding between technology of gluing and a technology of welding and also for input for a custom made single purpose machine made for welding of material Resysta. Tests were performed in exposure temperatures -30 °C, 20 °C and 60 °C. We will perform two tests; first test will focus on the tensile strength of glued and welded joints and second one will try to test of tensile strength of Resysta material. Experiments were conducted according to standards ČSN EN 205 and ISO 527-1 on the Instron 3365 testing machine. Laboratory tests showed that values of tensile strength were decreased while increasing the exposure temperature and this was consistent in every test performed. A statistical significance was also confirmed in work piece direction influence on a board. There were higher values of the tensile strength in longitudinal direction than in the transverse.

The aim of this work was to investigate the properties of bonded ballistic materialsBalistic composites are mainly glued to reduce weight while keeping their protective properties. On this basis, the materials used were ballistic steel, ceramics, rubber kevlar, non-gummed kevlar, Dyneema and fiberglass. For bonding used were a one-component adhesive Collano 36.104 and two-component adhesive Biresin U1305. The strength of the joint was measured in shear at tensile loads. From these results, deformation energy was further calculated.

This work was focused on the study of hydroxyapatite based bioceramic materials. These materials are generally very important for medical purposes, especially in the reconstruction and replacement of bone material. For medical applications, inert, bioactive or bioresorbable materials can be used. One of the common "bioactive" materials is hydroxyapatite, which forms a large part of human bone. Hydroxyapatite can be prepared by a wide variety of procedures, one of the most common methods is the precipitation reaction used in this work. To improve the biocompatibility of the bone replacement, porous structures with adequate mechanical stability are used. For the initial study of simulation of the behavior of biomaterials in the human body, called in vitro tests are used in solutions based on synthetic body fluids or cell media. The experimental part deals with the synthesis of hydroxyapatite powder and CA phase composite compounds. The reactions between the individual components were studied by thermal analysis and heat microscopy. The resulting products were analyzed for phase composition by X-ray diffraction. The prepared powders were further processed on foam structures by in situ foaming and sintering at a suitable temperature. In vitro tests, following the behavior of the prepared porous products in the synthetic body fluid, were performed for 7, 14 and 28 days. The monitored composites were then studied for biocompatibility by scanning electron microscopy. At the same time, the change in the concentration of Ca2+ and PO43- ions in the body fluids tested was monitored.

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.