Failure analysis of glazed LAS glass-ceramic containing cerium oxide

In this study a deep investigation of the correlation between microstructure and mechanical properties was performed on glass-ceramic materials containing cerium oxide. The glass-ceramic materials investigated were lithium-aluminum silicate based (LAS), obtained through different thermal cycles from the same parent glass. The mechanical properties were tested on the glass-ceramics with and without the application of a glaze. All the glass-ceramics were characterized by means of scanning electron microscopy (SEM), also in field emission guns geometry (FEG), energy-dispersive spectrometry (EDS), X-Ray diffraction (XRD), and 3-points mechanical flexural strength resistance test. This study has revealed that the microstructure of the glass-ceramic is mainly affected by the heating treatments holding times. The application of a glass coating leads to the formation of cerium oxide crystals at the glaze/glass-ceramic interface. This phenomenon is one of the main principal causes of the mechanical properties failure when a glaze is applied.