Application of Microtomography in Textile Metrology

Abstract

Porosity represents one of the parameters of knitted fabrics, which signifi cantly aff ects their air permeabi lity and thus the overall physiological comfort of knitted clothes. X-ray computed microtomography (CT) is a relatively new but not yet widely used method for studying textile porosity. The paper discusses the use of a 3D image of the textile structure obtained by applying CT in the textile metrology. Specifi cally, it deals with the analysis of options for determining the 3D porosity of knitted fabric by CT and subsequent analysis of the relationship of porosity versus the fabric permeability to air. The fi rst part of the article was aimed to analyse the suitability of application of CT to determine the 3D porosity of textile materials and determination of appropriate measurement conditions. Obtained porosity data measured by the 3D device SkyScan 1174 was compared to the porosity calculated by the standard mathematical model. The research results show that CT system is suitable alternative method for 3D porosity measurement. There is very small diff erence (about 6%) between the percentage of the air volume of the examined knitted fabric obtained by CT (64.6%) and porosity expressed through the volume fraction by standard mathematical model (70.6%). The last part analyses the dependent relationship between porosity of the knitted structures obtained by using CT SkyScan 1174 and air permeability measured on FX device 3300 according to EN ISO 9237. Analysis between air permeability and measured porosity of others knitted structures verifi ed correctness of suggested measurement process of 3D porosity.