Separate measurement of the expansion behavior of ceramic bodies and the glaze cannot record the effects of interactions and formation of intermediate layers that occur in practice. In the GST 420 PC glaze stress tester, a glazed rod is subjected to stress during heating and cooling and the bending that results is recorded. The direction and extent of bending make it possible to estimate the tensile and compressive stress and to define the temperature ranges over which pronounced changes in the state of stress occur during firing of a glazed ceramic.

The application is the same for enameled metal articles.

The target applications for the GST 420 PC glaze stress tester are primarily in production control for glazed ceramic articles and associated glaze processing.