INFLUENCE OF FLY ASH ADDED TO A CERAMIC BODY ON ITS THERMOPHYSICAL PROPERTIES.

We study thermal expansion, mass changes, heat capacity, and thermal diffusivity and conductivity for a ceramic body with 20 mass% and without fly ash content, using the thermodilatometric analysis, thermogravimetric analysis, differential thermal analysis, differential scanning calorimetry, and flash method. The measurements were performed: (a) for green samples either isothermally or by a linear heating up to a temperature 600 °C, 1050 °C, or 1100 °C, depending on the measurement method; (b) at the room temperature for samples preheated at 100 °C, 200 °C, ..., 1100 °C. In case (a) addition of fly ash changes the final contraction only above ~900 °C, while the thermal properties remain almost unchanged. In case (b) the final contraction of samples at 1100 °C is the same. The thermal diffusivity is nearly identical up to 700 °C, and fly ash causes the diffusivity to stay almost constant up to 1000 °C. [ABSTRACT FROM AUTHOR]