Gradual Degradation of Initially Porous Polycrystalline Ceramics Subjected to Quasi-Static Tension

Abstract

Ceramic materials exhibit under loading non-linear and inelastic response due to existence of initial porosity, plastic strains and growth of internal microdefects. These defects induce local stress concentrations and generation of micro and macrocracks. The concentration of defects usually occurs at intergranular boundaries, thus inducing anisotropic response of the representative element. The continuum models of damage growth account for these defects and provide the framework for material analysis, eg. [1,2,3]. In the paper the analysis of progressive damage of Al₂O₃ and MgO ceramic will be performed including R-curve effect.