Polycrystalline materials with pores:effective properties through a boundary element homogenization scheme

In this study, the influence of porosity on the elastic effective properties of polycrystallinematerials is investigated using a formulation built on a boundary integral representation of the elasticproblem for the grains, which are modeled as 3D linearly elastic orthotropic domains with arbitrary spatialorientation. The artificial polycrystalline morphology is represented using 3D Voronoi tessellations. Theformulation is expressed in terms of intergranular fields, namely displacements and tractions that play animportant role in polycrystalline micromechanics. The continuity of the aggregate is enforced throughsuitable intergranular conditions. The effective material properties are obtained through materialhomogenization, computing the volume averages of micro-strains and stresses and taking the ensembleaverage over a certain number of microstructural samples. In the proposed formulation, the volume fractionof pores, their size and distribution can be varied to better simulate the response of real porous materials. Theobtained results show the capability of the model to assess the macroscopic effects of porosity.