About this Abstract |
| Meeting |
MS&T24: Materials Science & Technology
|
| Symposium
|
Phase Transformations in Ceramics: Science and Applications
|
| Presentation Title |
Evolution of Phase Composition and Elastic Properties in Kaolin-Based Silicate Ceramics with Mullite Addition |
| Author(s) |
Petra Springer Simonova, Eva Gregorova, Willi Pabst, Petr Bezdička |
| On-Site Speaker (Planned) |
Petra Springer Simonova |
| Abstract Scope |
Kaolin-based silicate ceramics with mullite addition can be considered as model systems for high-alumina refractories. The suitability of these materials as potential candidates for high-temperature energy storage is currently investigated in a EU-co-funded project (OP JAK MATUR, project No. CZ.02.01.01/00/22_008/0004631). This contribution presents a study of kaolin-based ceramics with mullite additions, prepared by uniaxial pressing and firing in the temperature range 1100–1500 °C. The evolution of the phase composition, as determined via X-ray diffraction, including the X-ray amorphous alumina-silica phase, and the temperature dependence of Young’s modulus, as determined via the impulse excitation technique, is reported. It is shown that the mullite content formed from the amorphous phase shows a steep increase between 1100 and 1200 °C and a weakly increasing trend between 1200 and 1500 °C, with concomitant changes in stoichiometry. The surprising fact that relative Young’s modulus are consistently lower than theoretical predictions is discussed in detail. |