Influence of Illitic Clays on the Sintering, Properties, and Structure of Ceramic Stone Materials

The results of investigations of the structure and properties of conventional ceramic stone bodies, including leaners, fluxes, and clay materials (36, 14, and 50% by weight, respectively) in the initial composition, on systematic variations of the ratios kaolinite- and illite-containing clays and firing temperatures/times in the temperature range 1000 - 1300 degrees C are presented. The optimal ratios of kaolinite and illitic clays and the sintering conditions under which the ceramic properties of the material materialize are determined by means of investigations of the structure and phase composition as well as the dilatometric and ceramic properties. It is shown that the maximum compaction of ceramic (open porosity/water absorption 2 - 5%, apparent density >= 2 g/cm(3)) is achieved in the sinter state range 1150 - 1250 degrees C and is realized when the equivalent weight ratios of both clays is kept close to 1 : 1 in the initial makeups.