Modeling Residual Stresses in Ceramic Plates

The generation of residual stresses during cooling of layered ceramic plates has been modeled. Each plate comprises a body and two thin layers (engobe and glaze). The model takes into account two types of stresses: thermal stresses, resulting from temperature gradients inside the plate during cooling, and the stresses produced by the mismatch of the coefficient of thermal expansion (CTE) of the layers. The body has been simulated using a linear viscoelastic constitutive equation. The engobe and the glaze layer have been considered as elastic solids below a certain temperature (setting temperature: Ta). Above Ta these two layers have no mechanical influence on the body.