Internal Stresses in Model Ceramic Systems

Model ceramic systems of crystals and glass fabricated by vacuum hot compaction were used to study methods of detection of internal stress on the crystalline phase. Effects of the volume fraction of the glass, compaction temperature and time, and crystal particle size in modifying induced internal stress are presented. These effects, together with X‐ray diffraction and wetting studies, indicate that internal stress development is closely connected to wetting of the crystal by the glass and the formation of a second crystalline phase. Limited results regarding influence of internal stress on strength of ceramic bodies indicate that increasing internal stress on the crystal phase decreases the modulus of rupture when the particle size of the crystal component remains constant. The results of this work indicate that the full potential of ceramic systems may not be realized with the presence of internal stress.