LAUSR

Characterising the microstructure of foams is an important task for improving foam manufacturing processes and building foam numerical models. This study proposed a method for measuring the thickness of individual cell walls of closed-cell foams in micro-CT images. It comprises a distance transform on CT images to obtain thickness information of cell walls, a watershed transform on the distance matrix to locate the midlines of cell walls, identifying the intersections of midlines of cell walls by examining how many regions each pixel on the midlines of cell walls connects with, disconnecting and numbering the midlines of cell walls, extracting the distance values of the pixels on the midlines (or midplanes) of cell walls, and calculating the thickness of individual cell walls by multiplying the extracted distance values by two. Using this method, the thickness of cell walls of a polymeric closed-cell foam was measured. It was found that cell wall thickness measured in 2D images shows larger average values (around 1.5 times) and dispersion compared to that measured in volumetric images. This paper proposed a novel method to measure the thickness of individual cell walls in micro-CT images of closed-cell foams. It mainly consists of three steps: 1) Identifying the midlines or midplanes (in volumetric images) of cell walls 2) Disconnecting the midlines or midplanes of cell walls at intersections 3) Computing the nearest distance of pixels on the midlines or midplanes to black pixels (representing void phase) This article is protected by copyright. All rights reserved.