A Mechanical Model for the Lateral Compression of Woven Fabrics

Abstract

A mechanical model for the lateral compression of woven fabrics is derived from Van Wyk's compression law for fiber assemblies. The pressure ( P ) and thickness (v) relationship is P = a/ ( v -v')3. The parameter v' refers to the core of the fabric, which is incompressible over the pressure range 2-5000 gf/cm 2 . The parameter a refers to the compressible surface layers and is dependent on the mass of fibers in the surface layers and their orientation.A comparison is made of the results obtained with the KES-F fabric compression tester and the standard fabric thickness tester. The energy of compression is proportional to the cube root of the parameter a. The compressibility of the fabric is proportional to the energy of compression per unit volume of fabric. The changes that occur in the fabric surface layers during a typical fabric finishing process are investigated.The measurement of the lateral or thickness compression properties of fabrics forms an integral part of objective measurements currently being considered internationally for wool fabrics [ 12,17]. These objective measurements are intended to help maintain consistent quality in finished wool fabrics and to aid in product engineering of wool fabrics. An early paper [2] described the thickness-compression curve of fabrics. The effects of finishing treatments on the lateral compression curves of fabrics have been described [3,9,13], but the thickness-compression curves of fabrics have not been analyzed mechanically. An analysis of the mechanics of fabric compression may help in developing compression test methods and interpreting results. In this paper, we present a mechanical model that describes the compression curves measured on a large number of woven fabrics over the pressure range of 2-5000 gf/cm2. The model reduces the fabric to three layers -a relatively incompressible core layer in contact with a much more compressible surface layer on either side. The model is reconciled with both electron microscope evidence and optical measurements made on the fabrics.The model indicates that the DIN standard [6] for measuring fabric compression is very simply related to the compression test performed on the Kawabata evaluation system for fabrics . The change in the compression properties of wool fabrics in some commercial worsted fabric finishing processes is presented and interpreted in terms of the model.

Digital element simulation of aligned tows during compaction validated by computed tomography (CT)

“…Based upon these facts, the compaction process is taken as an important parameter of the manufacturing process (Robitaille and Gauvin, 1998). Extensive research has been done on the compaction behaviour of textiles (Chen and Chou, 1999;Chen et al, 2001;Chen et al, 2006;De Jong et al, 1986;Gutowski and Dillon, 1992;Latil et al, 2011;Nguyen et al, 2013;Pearce and Summerscales, 1995). Van Wyk (1946) was probably the first to treat the fibres under compression as a system of bending units.…”

Influence of Tow Architecture on Compaction and Nesting in Textile Preforms

“…Extensive research work has been reported in the literature on the compaction behaviour of different fabrics [4][5][6][7][8][9][10][11][12][13][14][15]. Van Wyk [16] was probably one of the first researchers to treat the fibres under compression as a system of bending units.…”

Effect of Finishing on Woven Fabric Structure and Compressional and Cyclic Multiaxial Strain Properties

“…Pressing and decatizing [4] leads to flattening of the compressive surface fabric layers. Therefore it is expected that finishing will reduce fabric compressibility and the compressive index and increase the linearity of compression.…”