Micromechanical modeling of compressive behavior in freeze‐casted ceramic

Abstract

In this study, a novel computational micromechanical framework is proposed to predict the effective mechanical properties of the ice‐templated ceramics under off‐axis compressive loading. The mechanical behavior is simulated by a computational micromechanical model and validated against experimental results. Smeared cracking approach was used to describe failure in ice‐templated alumina. The representative volume element (RVE) was developed based on the honeycomb analogy of lamellar walls considering the morphology of the material. The periodic boundary conditions were applied in RVE to simulate bulk behavior of the material. The compression testing was conducted on the ice‐templated alumina samples to obtain the effective compressive moduli and strength with different loading angles. Digital image correlation method was used to measure strain field during the experiment and quantify the effective misalignment angle corresponding to porous material. The effective stiffness and strength obtained from RVE analysis compared well with experimental results. The proposed micro‐mechanical RVE model allows for determining the properties of the ice‐templated porous ceramic for various off‐axis angles.