There is a glazing process in the production of ceramic products. Glazing refers to spraying a certain amount of glaze slurry, that is, glaze suspended in water, onto the surface of green body with compressed air. The green body quickly absorbs the water in the wet glaze to form a certain hard surface, and a 300-400 micron thick glaze layer is formed on the surface of the fired product. However, when many ceramic products are glazed, the glaze will shrink, that is, the glaze on the surface of ceramic products is missing in a large area. How to prevent glaze shrinkage in ceramic production?
1. Before spraying glaze, carefully clean the product to ensure smoothness and cleanness;
2. Spray green cloth with water before glazing, which helps to mix the residual dirt and soluble salts on the surface of the green body and put them on the glaze. However, if the green body has been scrubbed with sponge containing water within 2 hours before glazing, it is not necessary to spray water;
3. Use clay with low soluble salt to keep the model and floor clean. 03 BaC03 should be removed when reused.
4. Avoid getting oil or lubricating oil on the green body. The use of compressed air in the process of cleaning the green body before glaze spraying may bring in grease, so the compressed air should filter out the grease;
5. Avoid contacting or scraping the glaze layer after spraying glaze;
6. The use of micron fine raw materials can reduce the rate of glaze water penetrating into the green body. When the glaze on the surface of the green body is dried, the drying shrinkage is large and cracks are easy to occur. Therefore, the addition of clay in the glaze should not exceed 5%.
