Iznik tiles: A new production technology and respective characterization

This study investigated a new production technology for Iznik tiles. High quartz content of Iznik tiles was kept as it was and hydraulic pressing instead of tapping was used for shaping. Besides the traditional pouring technique, tiles were also glazed by spray coating. Characterization of the Iznik tiles were approached using different methodologies, including scanning electron microscopy plus energy dispersive X-ray spectrometry (SEM-EDX), Raman spectroscopy, atomic force microscopy (AFM), X-ray diffractometry (XRD) and dilatometry. Characterization results revealed that thermal expansion coefficients (TECs) of body, slip layer (thinned siliceous clay) and frit are 8.41, 8.48 and 8.32 x 10(-6) K-1, respectively, and matched which is fundamental to achieve increase in strength and keep the glaze in compressive stress. Raman signatures of the Iznik tiles agreed with the literature information. By double layer spray coating, smoother surfaces can be obtained on Iznik tiles than by traditional method of glazing.