Advanced Ceramics. VOCABULARY. Vitrification. Fired clay that has fused together completely, so that the pores between refractory particles are filled with glass and the body is impervious to water. Reaches temperature maturity, turns into a glass like substance, and loses all porosity.
The creation of ceramic forms by casting slip in plaster molds.
Adjustable tool for measuring inside/outside diameters, as in making lids.
A measurement of a material’s tendency to expand when heated and contract when cooled. The higher the coefficient of expansion, the lower the thermal shock resistance. In firing dissimilar materials in contact with one another the coefficient of expansion must be matched.
Process of reducing the upper diameter of a thrown form by working the walls of the rotating form inwards with fingers or rib, as in a bottle shape.
Fe2O3—powdered rust—refractory red in oxidation, converts to black iron (flux) in reduction and/or high-fire.
The process of returning dry unfired clay to a slip by soaking in water.
Hand-operated turntable for applying wax resist and banded decoration.
Rigid flat disc of wood, plastic, or plaster placed on wheelhead. When throwing is finished, bat is lifted off wheelhead, avoiding damage or warpage.
The process of cooling a heated object gradually to allow internal shrinkage stress to equalize without damage.
Machine that forces plastic clay through a die to produce extruded clay shapes.
Working the clay up and down in a cone shape on the wheel to align the platelets in a spiral formation and thus increase control in centering and throwing.
Fracture zone that results when clay components are pressed straight together without disrupting the surface (by scoring and adding slurry or by smearing together) to intermix the platelets. Parts hold together while wet and tacky, but will separate easily when dry or fired.
Decorating technique where textured or patterned material or object is pressed into clay surface.
Decorating technique where design is formed by cutting or carving shallow lines in clay surface.
Low-relief clay shapes added to scored, slurried leather-hard surface for decoration.
Using any tool to poke any type of hole in clay surface.
Method of achieving a shine by rubbing clay or slip with smooth hard object.
Surface decorating technique in which small coils or balls of clay are affixed to the damp or leather-hard surface, usually with a layer of slip.
Colored slips formulated to have low drying shrinkage, allowing application to bone-dry or bisque-fired surface before glazing. Commercial underglazes are available in a wide palette of colors primarily for low-fire, but many will survive high-fire.