Glossary

The thermal expansion of the glaze and body must match. In the ideal case, the thermal expansion of the glaze is equal to or less than the thermal expansion of the body. Otherwise, cracks in the glaze are to be expected. Once the body used is a porous earthenware, your ceramic will no longer be waterproof. If, on the other hand, the thermal expansion of the glaze is significantly below that of the body, this can lead to the glaze flaking off (this case is usually very rarely).

 

Specified as a measure of thermal expansion for the so-called TEC (coefficient of thermal expansion). In many cases, excessive thermal expansion of the glaze can be reduced by using 5-15% of a corresponding low-TEC frit. Especially with effect glazes, the use of this additional frit can sometimes result in a change in colour and effect.