Determination of the porosity in a bifacial fabric using micro-computed tomography and three-dimensional reconstruction

Fabric porosity affects the performance of textile materials, and characterization of the pore size in fabrics is a particularly difficult task. In this study, micro-computed tomography and reconstructed three dimensional (3D) images were used to accurately measure the fabric porosity and to determine the number, diameters, and locations of the pores. To validate the flexibility of the proposed technique, we analyzed woven, knitted, and bifacial fabrics made of wool/acrylic and polyester. Distributions of pore diameters and pore connections in the bifacial fabric confirmed that this fabric comprises a combination of woven and knitted structures. The volume porosities of the woven, knitted, and bifacial fabrics obtained from 3D reconstruction were similar to those calculated based on other techniques such as mathematical models. While the different fabric structures used in this study showed similar volume porosities, they had different air permeability. However, porosity analysis suggested new evidence to validate permeability measurements in fabrics. A new method for determining fabric surface and measuring fabric thickness is proposed, which accesses the number and diameters of inter-fiber pores. Having access to this type of information can potentially be used to engineer and to tune the performance of textiles.