Sintering and Technological Properties of Dry Pressed Ceramic Body Containing Kastamonu Mud and Clay

Abstract

Kastamonu is a city built on the valley of Karacomak River in Turkey. There is a mud which is used inside of the kiln for repairing kilnbricks. In this study, Kastamonu mud (KM) and clay were used in the ceramic recipe as raw materials to produce dry pressed ceramicbodies. Firstly, chemical compositions of used raw materials were determined by using XRF analysis. Ceramic mixture containingKastamonu mud and clay was prepared. It was mixed for 3 hours. Prepared mixture was dried and granulised by using sieve. AfterthenKastamonu mud containing 20 wt% and 30 wt% clay were shaped by dry pressing method using metal mold with 45 MPa pressingpressure. The samples were then sintered at 1050, 1100 and 1150 sintering temperatures. Green and sintered density, firing shrinkageand water absorption of samples were determined. Sintered density of the samples were measured by Archimed method. It wasconcluded that this material with the addition of clay can be used as a new ceramic raw material due to its suitable technologicalproperties at 1150C sintering temperature. Some coloured glaze recipes were applied on to the Kastamonu mud (KM) containing 20wt% clay body sintered at 1150°C. Especially, this dry pressed body is suitable for industrial forms with its artistic glazes. Sinteringand technological properties such as density, water absorption, firing shrinkage of each body were measured. Scanning electronmicroscopy (SEM) studies were carried out to analyse the microstructure and to see ceramic body-glaze interactions. The best firingshrinkage, water absorption and density values were obtained with KM 20 samples sintered at 1150°C as 12.9%, 5.2% and 2,57 g/$cm^3$, respectively.