The study of firing process of kaolinite-illite ceramic mixtures

Firing process of kaolinite-illite ceramic mixtures was studied. High purity illitic and kaolinitic clays were mixed in ratios 1:9, 3:7, 5:5, 7:3, and 9:1. The prepared samples were linearly heated from room temperature up to 1100 °C and down to the room temperature at the heating rate of 5 °C/min. Firing process was studied by thermodilatometry, thermogravimetry, development of bulk density and dynamic Young’s modulus. The final values of Young’s modulus increased linearly with increasing illite content. A more complicated relationship was observed by thermodilatometry. The best ratio between firing shrinkage and final value of Young’s modulus was found for the mixture 5:5.