Morphological implications on the mechanics of porous materials

Abstract

The mechanical properties of open-porous cellular materials are guided by their pore-network connectivity and their pore-wall morphologies. In this contribution, both these aspects will be discussed. First, the effect of the pore-network connectivity will be addressed. Here, the scaling exponent as observed in the power scaling relations between e.g., Young’s modulus and the relative density will be explored. While the open-cell foam model calculates the exponent to be 2 [1], many porous materials demonstrate an exponent between 3 and 4 [2]. The morphological implications towards this observation will be illustrated through computational modeling and finite element calculations. Moreover, many open-porous materials show a pearl-necklace-like pore-wall morphology [3]. There, the inter-particle necks play a significant role in determining the mechanical features of such materials, particularly their mode of deformation and failure [4]. This aspect will also be explored in detail.

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