Width-Wise Changes in Mechanical Properties of Warp Yarns and Woven Fabrics, Caused by Stresses and Strains in the Course of Weaving and Finishing

Abstract

Width-wise deformations of unsized warp yarns occurring in weaving and finishing are analysed. The analysis is performed on pure wool yarns and blends with polyester (PES) intended for warp. Tests are done on 3 fabric samples: on the yarn before warping, by pulling warp yarns from grey fabrics and by pulling warp yarns from the finished fabric throughout the fabric width. Samples of warp yarns are tested of grey and finished fabric throughout the fabric width. Two methods are used to analyse deformations occurring in weaving or finishing on warp yarns and fabric as a whole: testing breaking strength of both yarn and fabric and testing resistance of the yarn to wear. The results obtained are used to determine warp yarn and fabric deformations occurring in weaving and finishing throughout the fabric width, as based upon breaking strength and yarn resistance to wear. Highest level of deformation is found at selvedges or near them, being reduced in the direction of the centre of the fabric, with some oscillations.