Requirements For The Fineness of Enamel Slurry

Since the enamel frit is added with clay, water and electrolyte when it is ground into a slurry, the enamel slurry becomes a colloidal suspension system.

The finely dispersed particles of the enamel frit are ion-exchanged through the adsorption performance of the clay colloid for heterogeneous ions and some ions in the aqueous solution to form a water-soluble film with a certain thickness to enhance the suspending ability of the enamel slurry.
The composition of the enamel slurry and the particle size of the enamel slurry have a relatively important impact on the suspension performance, mainly depending on the amount of certain ions they can exchange.

The thickness of the enamel slurry has an impact on the enameling operation and the quality of the enamel products. Generally speaking, the finer the enamel slurry, the better its suspension, and the firing temperature will decrease accordingly, the enamel ground coat reacts more fully with the iron blank, and the adhesion strength of the ground coat will increase. However, when the enamel slurry is too fine, it is easy to increase the consistency of the enamel slurry, increase the thixotropy, it is not easy to paint, and it is easy to shrink. When the enamel slurry is too thick, the suspension is reduced, it is easy to precipitate, and the surface of the porcelain layer is poor in fineness, which affects the gloss.

Various enamel slurries have different requirements for the thickness of enamel slurries due to their different uses and enamelling requirements. For example, the mesh number of the ground coat and titanium enamel is 140 meshes, and the sieve margin is 1.0~1.5g; the crimped enamel is sieved 140 meshes, and the sieve margin is 3.0~4.0g; the bright base frit is sifted through the sieving steel plate at one time. 200 mesh screen with a sieve margin of 4.0~5.0; cast iron white ground coat screen with 200 mesh screen with a sieve margin of 0.5~1.0g; cast iron primary black bright ground coat with a 200 mesh screen with a sieve margin of 6.0~8.0g.