μCT-Based Analysis of the Solid Phase in Foams: Cell Wall Corrugation and other Microscopic Features

Abstract

This work presents a series of three-dimensional computational methods with the objective of analyzing and quantifying some important structural characteristics in a collection of low-density polyolefin-based foams. First, the solid phase tortuosity, local thickness, and surface curvature, have been determined over the solid phase of the foam. These parameters were used to quantify the presence of wrinkles located at the cell walls of the foams under study. In addition, a novel segmentation technique has been applied to the continuous solid phase. This novel method allows performing a separate analysis of the constituting elements of this phase, that is, cell struts and cell walls. The methodology is based on a solid classification algorithm and evaluates the local topological dissimilarities existing between these elements. Thanks to this method it was possible to perform a separate analysis of curvature, local thickness, and corrugation ratio in the solid constituents that reveals additional differences that were not detected in the first analysis of the continuous structure. The methods developed in this work are applicable to other types of porous materials in fields such as geoscience or biomedicine.

Fatigue mechanisms of a closed cell elastomeric foam: A mechanical and microstructural study using ex situ X-ray microtomography

“…More recently, this 3D imaging technique became a promising tool to observe fatigue-induced fracture initiation and propagation in brittle foams [33] although it has never been used to study the fatigue of elastomeric foams. Beyond the preservation of the bulk structures of imaged samples, the technique offers the opportunity to quantify their 3D microstructural descriptors without extrapolation from 2D images such as with SEM or optical observations [34]. Thus, 3D in-situ observations using X-Ray microtomography were carried out during monotonic compression tests (and sometimes combined with finite element analysis or digital volume correlation) to quantify the deformation mechanism at the cell wall scale in elastomeric foams [35,36].…”