The Influence Factors And The Mechanism Of Ceramic Glaze Abrasive Resistance

China is the largest country in the production of building ceramics.In recent years,the annual output of ceramic tiles has exceeded 9 billion square meters,most of which are glazed products.The ceramic body of glazed tile can be made from low-quality raw materials with deep color and huge storage,because it covers the surface with the glaze.Therefore,the proportion of glazed tiles in wall and floor tiles is encouraged to be increased in the national policy.The glaze wear resistance is a key performance of ceramic tiles.Enhancing wear resistance not only benefits the improvement of the glazed tiles quality,but also helps to reduce the consumption of high-quality resources,which has important social and economic significance.There are many shortcomings in the ISO standard and other standards for determining the glaze wear resistance in practical application,and thus the wear resistance of various glazes cannot be objectively and accurately evaluated.In this paper,through a large number of comparative experiments and analysis concerning various existing glaze wear resistance test methods,a test method for characterizing the glaze wear by weighing the mass loss of the surface wear method was first proposed,and at the same time,its working parameters were determined.This method requires the low surface flatness of the sample and is featured with wide adaptability and low error.It is not only objective and accurate,but also can be used for determining the wear resistance of the ultra-thin glaze layer with a thickness of only 30?m.This method can be used to test the wear resistance of tiles,and it is hopeful that glazed tiles and unglazed tiles can be integrated into a unified evaluation system through this test method.The effect of ZrSiO₄ content,grain size and the preparation process on the glaze wear resistance was investigated,because ZrSiO₄ is the most commonly used reinforcing phase in abrasion-resisting glazes.The results showed that compared with the basic glaze,the glaze wear resistance increased by 43%,73%,and 140%respectively when the addition amount of zirconium silicate was 10 wt%,20 wt%,and 30 wt%accordingly.The grain size also had a significant effect on the glaze wear resistance.The abrasive resistance of the glaze containing the zircon with an average grain size of about 1.5?m was 28% higher than that with an average grain size of 11.1?m.Compared with the zircon raw glaze with the same ZrO₂ content,the grain size in the glaze was smaller and the grain coverage uniformity was higher.Thus the wear resistance was significantly improved.A ZrO₂ and ZrSiO₄ grains intergrown glaze was prepared by the addition of zirconia in the frit glaze.The wear resistance of the glaze with 13.4 wt%ZrO₂ addition was 107%higher than that with 20 wt%ZrSiO₄?with equivalent zirconia?.In the K₂O-Na₂O-CaO-Al₂O₃-SiO₂-ZrO₂ frit glaze system,by increasing the amount of[AlO₄]in the glass network structure,the diffusion of Si⁴⁺was limited,thereby suppressing the formation of ZrSiO₄ from ZrO₂.Thus,submicro zirconia grains can be intergrown in the zircon opaque glaze,and the opaque glaze with low ZrO₂ content?5 wt%?and high whiteness?L^*value of 96?was prepared.Compared with the similar whiteness zircon glaze,more than 40%of the ZrO₂ content was decreased.The effect of compressive stress on glaze wear resistance was systematically studied by adjusting the thermal expansion of ceramic body with fused quartz.The elastic modulus and Poisson's ratio of the ceramic body and the glaze were measured by a Two dimension-Digital Image Correlation?2D-DIC?system,and the prestress due to the different thermal expansion of the glaze and the body was calculated.The prestress value of the glazed tile was also gauged by DIC and stress-release method.It is the first time to quantitatively confirm that the prestress on the glaze caused by the different thermal expansion and the rapid cooling can reinforce the glaze wear resistance.The results showed that the glaze weight loss was increased as reducing the prestress.Finally,the high wear resistance transparent glaze was prepared by the compound reinforcement of prestress and grain,where cordierite with high hardness,low thermal expansion and refractive index close to the glass phase served as the main grain phase.The obtained prestress of glaze was 239.4 MPa and its wear resistance was improved by 92.1%?128.2% when compared with that of the transparent glazed tile products.