Abstract
The thermal expansion of ceramic samples prepared from the mixture of 50% kaolin, 25% feldspar and 25% quartz was studied in the temperature range of 20 - 1000 °C. The samples were cut from the surface layer of an extruded ceramic cylindrical body. The X-ray structural analysis showed that the basal planes of kaolinite crystals in the samples are predominantly perpendicular to the radius of the blank. The observed shrinkage of the samples is caused by evaporation of the capillary water, dehydroxylation, and high-temperature changes in metakolinite. The shrinkage is larger in samples with kaolinite crystals oriented predominantly perpendicular to the radius of the blank. High temperature firing does not eliminate the texture.