Graphite

Graphite is typically applied as a dry powder, spray suspension, or paste to the pressing die surfaces. During pressing, the graphite particles form a lubricating film at the die-ceramic interface, reducing friction forces during pressing and ejection, preventing surface damage to the pressed ceramic body.

Yes. Graphite is used as a coating material on kiln furniture (setters, saggers, props) to prevent ceramic ware from sticking to the kiln furniture during firing. The graphite coating burns off at higher temperatures without leaving residue on the ceramic surface.

Graphite used on mould surfaces is generally not incorporated into the ceramic body. However, if applied to the ceramic surface, graphite burns off at firing temperatures above 400°C in oxidising atmospheres. Care must be taken to ensure complete burn-off before the ceramic body reaches densification temperature to avoid carbon-related defects.

Graphite's combination of excellent lubrication, thermal stability, chemical inertness, and clean burn-off behaviour makes it uniquely suited for ceramic pressing operations. Organic lubricants may leave residues that cause glazing defects, while graphite burns off cleanly without contaminating the ceramic.

Graphite is most commonly used in the dry pressing of wall and floor tiles, electrical insulator forming (extrusion and pressing), refractory ceramic pressing, and technical ceramic component manufacturing where consistent demoulding and surface quality are critical processing requirements.