The formation of ceramics takes the fine, platy morphology of clay particles which is then used to advantage the forming of any clay-based ceramic products.
Entirely dependant on the amount of water that is added, clay-water bodies can be stiff or plastic. Plasticity is caused by the clay plate-shaped particles crossing over each other during the flow. If there is a higher water content paired with dispersing agents to keep clay particles in suspension, readily flowable suspensions can be produced. These suspensions are called slips or slurries and are used in the slip casting of clay bodies.
Following drying, the clay-based ceramics will be put through gradual heating to remove any structural water, burn off any organic binders used in forming, to decompose, and also to achieve consolidation of the ware.
Batches of products i.e a special range, are produced in smaller volumes and can be cycled up and down in batch furnaces. However, the majority of mass-produced traditional ceramics are fired in tunnel kilns. Tunnel kilns are made up of continuous conveyor belt or railcar operations, with the ware traversing the kiln and gradually being heated from room temperature, though a hot zone and then back down to room temperature.
If the fired ceramic ware is porous and the desire i fluid impermeability, or a decorative finish is desired, the product can be glazed.
During the process of glazing, a glass-forming formulation is ground and suspended in an appropriate solvent. The fired ceramic body is dipped in or painting with the glazing slurry. It is then refired at a temperature that’s lower that its initial firing temperature but high enough to vitrify the glass formulation.