The usage of derbent dolomite in ceramic production


Aras A.

EURO CERAMICS VIII, PTS 1-3, ss.1443-1446, 2004 (SCI İndekslerine Giren Dergi) identifier

Özet

The aim of this paper is to search the usage of dolomite occurred in the Neogene stratigraphy in the region of Derbent village as a ceramic raw material. Five different mixtures containing Derbent dolomite and tile clays were prepared to study the effect of dolomite in ceramic body. The firing shrinkages, green shrinkages, firing bending strength, green bending strength, water absorption and fired color parameters (L*, a*, b*) were measured from green bodies and ceramic bodies fired at 1150degreesC. It was shown that increasing the proportion of dolomite in starting composition increases the dry and firing shrinkages, dry and firing bending strengths and decreases the water absorption. After firing at 1150degreesC, the firing colors evolve from light beige to beige by increasing dolomite content. The firing beige colour is characterized by high CaO+MgO contents of whole chemical composition. By increasing firing temperature to 1150degreesC, the amount of glassy phase increases and Ca-Mg silicates phases occur. But, the total shrinkage of the bodies containing more than 10 % dolomite is higher than industrial limits. Another negative property of these bodies is their slight warpage at 1150degreesC.