Experiments and Model Simulations of the Viscosity and Dilatation of Glass Coatings with Temperature Dependence

Glass coatings on ceramics or metals are microcomposite materials, consisting of granular oxide phases as pigments and small bubbles that are distributed in glass. Knowledge of dilatation and viscosity versus temperature is essential for applications and simulation methods are necessary. However, the significance of the models depends on the specificity of the compositions and microstructure of glass-containing pigments. In this study, the viscosity and dilatation of glass coatings were characterized by dilatometry and the sessile drop method. The results show how the physical properties vary with the quantity of zircon grains and bubbles. Simulations with calculation methods for bulk glasses show discrepancies with the experiments, which are caused by the presence of zircon grains and bubbles. We provide evidence that improved models can be obtained by adding equations describing the behavior of glasses containing rigid inclusions and bubbles. The resulting methods provide the opportunity to discover new composition areas of glass coatings having predefined combinations of properties.