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Experimental Design for Ceramic Panel ProductionUmirova, Arailym January 2021 (has links)
This thesis work is a continuation of a project aimed at the consolidation of insulation material (IM) to produce porous ceramics with sufficient porosity and compression strength for post-insulation of buildings. The porous structure and contact points are tailored to produce IM with ultra-low thermal conductivity. One of the main goals is to introduce expandable microspheres, that are perfect lightweight fillers and blowing agents into production. They are relatively new materials in the market which are used to manufacture products with low weight and controlled foam structure. Therefore, it is of interest to be integrated into the construction field as a component for insulating materials. The project is built on the advanced structuring of porous materials with tailored porosity to offer 5-10 times lower thermal conductivity value providing adequate insulation with an insulation cover of 2-10 mm in thickness. Enhancing the insulating capacity allows to limit the use of energy to improve energy efficiency. Thus, less energy is required to heat or cool the indoor climate. The success in achieving such thin effective IM will eliminate the need for any modification of existing window frames, electrical and heating installations. In the first stage, it is necessary to confirm the entire concept of creating a thermal IM with a controlled porous structure using various compositions of materials and an assessment of the structure, porosity, and functional properties. This project focuses on developing a composition of ceramic panels. The various components of the ceramic panels including the type of ceramic are adjusted and their effects on the composition are described. Pure alumina, activated alumina and silica have been investigated to find the optimized quality and price. In addition, various methods and conditions have been implemented for panel fabrication. Prototypes of ceramic panels are prepared for demonstration, followed by upscaling at the facilities of industrial partners. The project has been performed in collaboration with companies i.e., Nouryon, HIPOR Materials AB, and LindePac AB as the industrial partner.
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Vývoj mikrostruktury pokročilých oxidových keramických materiálů při rychlém slinování / The microstructure evaluation of advanced oxide ceramics during fast sinteringPrajzler, Vladimír January 2017 (has links)
The diploma thesis deals with influence of fast pressure-less sintering on the microstructure of advanced ceramic materials, namely -Al2O3 and tetragonal ZrO2 (doped by 3 mol% Y2O3) with particle sizes ranging from 60 nm to 270 nm. Fast and controlled heating rate was enabled by utilization of the special superkanthal furnace with moving sample holder. Defect-free bulk and dense samples were prepared using heating rates in order of 100-200 °C/min. Higher densities reached the samples pressed by higher pressures; the specimens with densities higher than 99 % t.d. were prepared within tens of minutes for alumina as well as for zirconia with very low thermal conductivity. Different behavior was observed only for material TZ-3Y, which exhibited core-shell structure with dense surface and porous centre after sintering at heating rates higher than 10 °C/min. It was shown in this work that such behavior was not primarily caused by the high thermal gradient resulting from high heating rates. Its creation was probably caused by chlorine impurities. The mechanism of desintering of these samples was described and eliminated by calcination of the samples at 1000 °C for 10 hours prior to fast sintering at 1500 °C, so even this material could be fast sintered up to 99.9 % theoretical density.
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