Structure and thermal properties of the fritted glazes in SiO2–Al2O3–CaO–MgO–Na2O–K2O–ZnO system

Abstract

In this work, the structure and thermal properties of aluminosilicate fritted glazes in SiO2–Al2O3–CaO–MgO–Na2O–K2O–ZnO system with (4.0 mol%) and without addition of ZnO were examined by GIXRD, FTIR, MAS-NMR and thermal methods (DTA, DIL). It has been found that the all experimental glazes are amorphous material (transparent glazes). On the base of spectroscopic investigations, it was found that zinc ions exist in the network glazes in the octahedral coordination—Zn2+ ions play a network modifier role in structure of glazes. An analysis of the data obtained from thermal tests showed that addition of ZnO into chemical composition results in decrease in glass transition temperature value (Tg) for all glazes (DTA, DIL). The coefficient of thermal expansion (α) is decreased as the whole measurement range for one series of fritted glazes.