Macroscopic Properties of Inhomogeneous Material with Randomly Distributed Pores

Abstract

Porous materials such as engineering ceramics and metal foams have a specific feature such that internal structure has a significant influence on the mechanical properties from the viewpoint of porosity and morphology. This paper discusses the relationship between microscopic morphology and macroscopic properties of the porous materials based on the homogenization technique, in which pores are randomly distributed over the domain. Various types of pores are examined and the conjunction between different elemental types is discussed. A wide range of porosity is covered from a low porosity of 5% such as engineering ceramics to 80% of foam-like materials within the same numerical strategy. It is found that the macroscopic property with low porosity shows good agreement with both experimental curve and micromechanics prediction, in which the elasticity coefficient is affected by morphology of internal structure. In contrast with the low porosity, the morphology effect diminishes and is hardly observed in high porosity region where the macroscopic stiffness is almost linear on the porosity.