Evaluating the residual stresses and fracture behavior of glass-ceramics by numerical modeling

Residual stresses often arise after glass crystallization due to the residual glass and crystal phases` thermal and elastic properties mismatch. Using the Positional Finite Element Method , we developed a computational tool for nonlinear 2D geometric analysis to simulate residual stresses from crystal growth in a glass matrix. We implemented a damage model in which interface elements are introduced into the mesh. These elements` elastic modules were penalized after reaching a tensile stress limit to simulate crack propagation. The crystal mesh was generated separately and included in the glass mesh via kinematic compatibility without introducing degrees of freedom nor requiring mesh conformity. Results were consistent with analytical calculations using Selsing`s model. The fracture mode in crystal-glass composite microstructures with different signs of thermal expansion mismatch is closely in accordance with the microstructure pictures in the literature. The adapted damage model showed excellent potential in evaluating and predicting crack patterns due to residual stresses in glass-ceramics.