Effect of gelatin gel strength on microstructures and mechanical properties of cellular ceramics created by gelation freezing route

Macroporous ceramics having unique pore morphologies with ceramic bridges, unidirectional cellular pores, and bamboo-like cells were fabricated by freezing gels with ceramic powder and various gelatin contents. Varying gel strengths were found to be effective for control of the pore architecture from open to closed pore channels. The proposed process is a relatively simple and versatile way to produce tailored pore configurations via a gelation freezing route. In addition, the relationship between the microstructure and mechanical properties of the resulting ceramics was discussed using a multiscale modeling technique, in which a homogenization method was conducted with microscopic models created from three dimensional images, global stress distributions in macroscopic samples by finite element method and local stress distributions. The simulation results were relatively consistent with the experimental results. The multiscale modeling technique was thus confirmed to be a strong tool for the prediction of the mechanical responses of porous ceramics.