Simulation of the elastic properties of porous ceramics with realistic microstructure.
Résumé
Quasi-static discrete element method (DEM) simulations are used to model the elastic behavior of porous ceramic obtained by partial sintering. The porous ceramic is modeled as a set of particles bonded by solid necks. A new approach introducing bond interactions is proposed to allow, in particular, the correct prediction of Poisson's ratio. It leads to a simple formulation that takes into account the deformation of a particle subjected to multiple contact forces, without the complexity of a full finite element method (FEM) analysis. The advantage of this new formulation is demonstrated, first by a comparison with FEM calculations on a simple test case, and then by a comparison with experimental results and other models from the literature on random aggregates of partially sintered particles. The proposed model with bond interactions correctly predicts Poisson's ratio of porous ceramics and improves the accuracy of Young's modulus when compared with the DEM model without bond interactions.