Image-based modeling and elastic analysis of porous ceramics by the homogenization method

A three-dimensional elastic analysis system for porous ceramics has been built. In this system, three-dimensional morphology of pores is modeled using voxel (volume pixel) elements from digital images. Elastic analysis with this image-based finite element model is performed by the homogenization method. In order to investigate this analysis system, the elastic properties and behavior of porous Al₂O₃ with spherical pores on the order of 1% by volume were computed. Young's moduli obtained by the homogenization method were consistent with both experimental and theoretical values. Using computed moduli of elasticity, the state of local stress concentration around the pores in a bending test was calculated together with the global stress in the sample. It was found that the dependence of the bending strength upon porosity can be described by taking into account local stresses around the pores. The combination of image-based modeling and homogenization method is a useful way to analyze the mechanical behavior of porous ceramics especially with inhomogeneous morphology.