Effect Of High Temperature Liquid Phase Viscosity On High Temperature Plastic Deformation In Sanitary Ceramics

Because the clay-based ceramics produce a large amount of liquid at high temperatures,the blanks are softened and deformed.The deformation of the blanks is related to the thickness of the blanks.The thicker wall of building ceramics has smaller high-temperature plastic deformation,but this causes the construction sanitary ceramics to be heavier.The large consumption of clay resources will directly lead to a sharp deterioration of the ecological environment.The relationship between the liquidus viscosity generated in ceramic bodies at high temperatures and the plastic high temperature plastic deformation variables is unknown.In this dissertation,the liquid-phase viscosity of K-Al-Si system was measured and a suitable viscosity model was found.At the same time,the mullite area of 1300°C and 1400°C in K₂O-Al₂O₃-SiO₂ phase diagram was redefined.Isotherms provide theoretical guidance for improving the resistance of ceramics to plastic deformation at high temperatures,and provide technical means for energy conservation,emission reduction and sustainable development of the building sanitary ceramics industry.In this paper,XRD,XRF and EPMA are used to analyze the phase and chemical composition of the sample.The main research results are as follows:?1?The viscosity model that is most suitable for the K-Al-Si system is discussed,and the relationship between the high temperature liquid viscosity and the high temperature plastic deformation variables of the sanitary ceramics is studied.A series of ceramic samples were prepared using kaolin,potash feldspar,albite,calcite and quartz as raw materials.After the sample was fired,the water absorption,porosity and bulk density of the sample were measured,and the plastic deformation of the strip sample was measured.The sample glass phase was analyzed by EDS and the glass phase of the sample was measured.chemical composition.The Riboud model was selected to predict the high temperature liquidus viscosity of sanitary ceramics.According to the Riboud model's prediction,when the high temperature liquid viscosity is less than 2×10⁴Pa·s,the deformation index increases significantly with the decrease of viscosity;when the high temperature liquid When the phase viscosity is greater than 2×10⁴Pa·s,the change in the deformation index does not change as the viscosity decreases.The high temperature plastic deformation of sanitary ceramics is related to the high temperature liquid viscosity.?2?In order to study the viscosity model that is most suitable for the K-Al-Si system,the high-temperature liquid-phase viscosity of the hygienic ceramic was measured and a suitable model was found to predict the liquid-phase viscosity of the K-Al-Si system.Potassium feldspar,shale and silica,alumina,iron oxide,calcium carbonate,sodium bicarbonate,and potassium bicarbonate are used as raw materials,and the chemical composition corresponding to the test results is matched.With a rotational viscometer,the viscosity was measured at high temperatures.After the measurement,the quantitative XRF analysis was performed on the quenched sample and calculated using the viscosity formula.For liquid phase viscosity of sanitary ceramics,the viscosity decreases with increasing temperature;the higher the Al₂O₃and SiO₂ content,the greater the viscosity;the higher the alkali metal oxide content,the lower the viscosity;when the high temperature liquid viscosity is less than5000Pa·s When the temperature changes,it will bring about a significant change in viscosity;when the high-temperature liquid viscosity is greater than 5000Pa·s,with the increase of temperature,the change of liquid viscosity is not very obvious.When some fine solid particles are suspended in the liquid phase,the viscosity of the liquid phase rises sharply and the pure liquid viscosity model no longer applies.The viscosity predicted by the Urbain model is larger than the actual viscosity,which is not suitable for the prediction of the viscosity of the K-Al-Si system.The results show that the Riboud model is also not suitable for predicting the viscosity of the hygienic ceramic silicate melt.In the A21,A22 and A62 samples,the SW model had the best prediction effect,while in the A23,A61 and A63 samples,the M-SW model had the best prediction effect.?3?The liquidus at 1300°C and 1400°C in the mullite region of the K₂O-Al₂O₃-SiO₂ phase diagram was redefined.Using silica,alumina,and potassium bicarbonate as raw materials,the chemical composition of the 1300°C and 1400°C isotherm points in the mullite zone of the K₂O-Al₂O₃-SiO₂ system was matched.XRD and WDS were used to analyze the chemical composition of the phases and phases of the samples.The 1300°C and 1400°C isotherms in the mullite zone of the K₂O-Al₂O₃-SiO₂ system were determined.The results show that the re-determined two isotherms are close to the previous isotherms,but the re-determined isotherms are shifted a little further to the left than previously determined isotherms.