The dried crucible should be inspected according to the standard of semi-finished products. Qualified products will come into the glaze coating process. The glaze will be loaded and fired after it is dry and solid. The purpose of firing is to enhance the density and mechanical strength of the crucible and improve the quality of the product. The glaze is anti-oxidation glaze to protect the crucible from oxidation during sintering
Sometimes cracks and blisters and pockmarks occur in the glazed surface, which has no effect on the service life of the crucibles. The reasons for this phenomenon are: the glass content in the glaze proportion is large, the glaze particles are big, the mixing is not uniform, there are many organic components in the glaze, and bubbles are produced during sintering and melting. At a certain temperature, the bubble is damaged to form pockmarks. The cracking of glaze layer is a natural phenomenon after sudden cooling, which is caused by the rapid cooling of crucible in the kiln and the different shrinkage of glaze glass and crucible embryo.