Experimental and numerical estimation of strength and fragmentation of different porosity alumina ceramics

Highlights: • The tensile strength of ceramic disks vs the porosity was found as exponential law. • Voxel element mechanical properties were appointed by local porosity. • Stochastic voxel model of ceramics is able to get realistic fragmentation. - Abstract: Ceramics are widely used in many applications as construction material. However, their strength and fragmentation details under tensile loading are not fully understood. In this work, the results of experimental and numerical strength investigations of hot-pressed alumina ceramics are presented. The disk-shape specimens with different porosities were subjected to bending test up to failure. Finite element analysis was performed for estimation of ceramic disk tensile strength. Elastic properties of porous ceramics for numerical simulations were determined with use of existing modulus–porosity relations and current experimental data. Three-dimensional models of test specimens with random distribution of strength and porosity based on voxel discretization were created by C ++ program and implemented in LS-DYNA. Then they were used to simulate the specimen fracture and fragmentation. Obtained numerical data are in a good agreement with experimental results.