Investigation of sintering behavior of sanitaryware ceramics by controlling glassy phase

The focus of this study was to investigate the effects of glassy and crystalline phases in sintering behavior of the sanitaryware body. To achieve this aim, two different phase analysis methods, the ratio of slopes and Rietveld methods, were compared. This research was carried out in three steps by using X-ray analysis values. In the first step, different amounts of metallic Si were added to pure mullite and quartz materials and their reference analysis lines were drawn. Secondly, sanitaryware samples were analyzed and their analysis lines were also drawn and compared with references. Therefore, a comparison between the slopes of the reference and analysis lines was allowed for the determination of the amount of quartz, mullite, and amorphous phases as 22.1, 18.8, and 59.1 wt.%, respectively. These results were used to estimate the chemical composition of the glassy phase that formed in standard sanitaryware microstructure. In the last step of research, new glassy phase compositions were prepared based on a standard sanitaryware glassy phase composition. Different mixture ratios of alkaline and earth alkaline oxides (Na2O/K2O, Na2O + K2O, SiO2/Al2O3, and MgO/CaO) were used to modify the glassy phase compositions. Results show that softening point and viscosity of the glassy phase can be controlled by controlling these certain parameters, and this helps to consume energy in the sintering process.