What are the defects and overcoming methods of custom glaze for bone china cups?

Defects of custom glaze for bone china cups and how to overcome them:

Mainly include: glaze corrugation, glaze matt, glaze shrinkage, glaze bubbles and pinholes, etc.

The main ways to overcome it are: when the glaze surface is corrugated, the specific gravity of the glaze slurry can be reduced, the high-temperature viscosity of the glaze can be reduced, the temperature difference in the kiln can be reduced, and the reduction flame can be used for firing. When the glaze surface is matte, rationally prepare the glaze formula and set the frit firing temperature to reduce the impurities brought in during ball milling. It can be fired with a reducing flame to shorten the high-temperature cooling time. When shrinking the glaze, the drying shrinkage of the glaze layer is reduced, and the preheating stage is slow. When glaze bubbles and pinholes, reduce the large amount of pyrolysis products contained in the raw materials, reduce the specific gravity of the glaze slurry, and avoid over-firing.

Reasons for custom shrinkage of bone china cups and how to overcome them:

Reasons for glaze shrinkage:

1. The wettability of the glaze to the base is poor, the viscosity is high at high temperature, and the surface tension is large.
2. The glaze layer dries and shrinks.
3. The adhesion of the glaze layer to the body is poor.
4. The storage time of the body glaze is long.
5. When the glaze is fired, the temperature rises too quickly in the initial stage of preheating.

Overcoming methods:

1. Reduce the content of clay, zinc oxide and aluminum oxide.
2. Increase the particle size of glaze slurry and reduce the specific gravity of glaze slurry.
3. Increase the firing preheating time.