Preparation of glass-ceramic glazes in the SiO2-Al2O3-CaO-MgO-K2O-Na2O-ZnO system by variable content of ZnO

This paper is focused on glass-ceramic glazes from the SiO2-Al2O3-CaO-MgO-K2O-Na2O system with ZnO additions (2.5, 5, 10, 15, 15, 20 and 25 wt%). The compositions were designed based on constant molar ratio of SiO2/Al2O3. In the resulting glazes diopside (CaMg[Si2O6]), willemite (Zn2SiO4) and vitreous phase were identified by X-ray diffraction. Morphological and structural date of these glazes were supplementary determined by EPMA, FTIR and Raman Spectroscopy. DSC analysis was carried out to characterize thermal properties of the materials.