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Dynamical thermomechanical analysis of 5 illite-based clays from deposits in Slovakia, Estonia, Latvia, and Hungary is presented. The clays consist of illite (37&ndash, 80 mass%), quartz (12&ndash, 48 mass%), K-feldspar (4&ndash, 13 mass%), kaolinite (0&ndash, 18 mass%), and calcite (0&ndash, 3 mass%). Young&rsquo, s modulus is measured during the heating and cooling stages of firing (25 &deg, C &rarr, 1100 &deg, 25 &deg, C). The liberation of the physically bound water increases Young&rsquo, s modulus by &sim, 70% for all studied clays. By increasing the temperature, dehydroxylation and the &alpha, &rarr, &beta, transition of quartz take place without a significant effect on Young&rsquo, s modulus. Sintering, which starts at 800 &deg, C, leads to an intensive increase in Young&rsquo, s modulus up to the highest temperature (1100 &deg, C). The increase remains also in the early stage of cooling (1100 &deg, 800 &deg, C). This increase of Young&rsquo, s modulus is also the result of solidification of the glassy phase, which is finished at &sim, 750 &deg, C. A sharp minimum of Young&rsquo, s modulus is observed at around the &beta, &alpha, transition of quartz. Then, Young&rsquo, s modulus still decreases its value down to the room temperature. The physical processes observed during heating and cooling do not differ in nature for the studied clays. Values of Young&rsquo, s modulus vary at around 8 GPa, up to 800 &deg, C. During sintering, Young&rsquo, s modulus reaches values from 30 GPa to 70 GPa for the studied clays. The microstructure and composition given by the origin of the clay play a cardinal role for the Young&rsquo, s modulus of the final ceramic body.

Tungsten-based materials are the prime candidate plasma-facing materials for future fusion reactors, such as DEMO. Spark plasma sintering is a prospective fabrication technology with several advantageous features. The concurrent application of electric current, temperature and pressure enhances the sintering process, allowing for lower temperatures and shorter sintering times than traditional powder metallurgy processes. This in turn helps to avoid excessive grain growth and phase segregation in W-alloys. This study is focused on several factors that may influence the homogeneity of the sintered compacts&mdash, namely the diffusion of carbon from the graphite die, purity of the powder and sintering conditions. The following characteristics of spark plasma-sintered tungsten compacts were studied: composition (especially carbon and oxygen content), porosity, mechanical properties (hardness and fracture strength), and thermal diffusivity. The effects of the abovementioned processing factors were quantified, and local variations of selected properties were assessed.