Investigation on bending and shear rigidities of plain woven fabrics having similar areal density

Purpose Bending and shear rigidities of woven fabrics depend on fibre, yarn and fabric-related parameters. However, there is lack of research efforts to understand how bending and shear rigidities change in woven fabrics having similar areal density. The purpose of this paper is to investigate the change in bending and shear rigidities in plain woven fabrics having similar areal density. Design/methodology/approach A total of 18 fabrics were woven (9 each for 100 per cent cotton and 100 per cent polyester) keeping the areal density same. Yarns of 20, 30 and 40 Ne were used in warp and weft wise directions and fabric sett was adjusted to attain the desired areal density. Findings When warp yarns become finer, keeping weft yarns same, bending rigidity remains unchanged but shear rigidity increases in warp wise direction. When weft yarns are made finer, keeping the warp yarns same, both the bending and shear rigidities of fabric increase in warp wise direction. Similar results for fabric bending and shear rigidities were obtained in transpose direction. There is a strong association between fabric shear rigidity and number of interlacement points per unit area of fabric even when fabric areal density is same. Originality/value Very limited research has been reported on the low-stress mechanical properties of woven fabrics having similar areal density. A novel attempt has been made in this research work to investigate the bending and shear rigidities of woven fabrics having similar areal density. Besides, it has been shown that it is possible to design a set of woven fabrics having similar bending rigidity but different shear rigidity.

Analysis of shear characteristics of woven fabrics and their interaction with fabric integrated structural factors

Behavior of woven fabrics during complex deformations is most influentially affected by their shear behavior. Shear characteristics of woven fabrics can be explained by fabric shear rigidity and shear hysteresis. In this study, the effects of weft density, weft count, and fiber type on shear behavior of woven fabrics in the principal directions of fabric were statistically evaluated. Statistical methods such as multiple linear regression analysis, univariate test, and correlation analysis were also applied. The univariate test results confirmed that the weft density is the most dominant parameter that affects fabric shear properties. Multiple linear regression results point to poor shear behavior in woven fabrics with cotton weft yarns. In addition, correlation between the shear rigidity of the fabrics along principal directions with the Milasius fabric firmness factor and the fabric cover factor as integrated structural parameters was established. High correlation was found to exist among Milasius fabric firmness factor, fabric cover factor, and shear rigidity of fabrics along principal directions.

Prediction of Certain Low Stress Mechanical Properties of Knitted Fabrics from Their Structural Parameters

Knitted fabrics are preferred as clothing materials because of of their outstanding comfort quality. 16 plain knitted fabric samples were produced from 4 combed ring spun yarn of linear densities 29.5 Tex, 23.6, Tex 19.7 Tex and 17.4 Tex and 4 different stitch lengths from each yarn linear density were selected for this study. The fabric samples were relaxed and then tested for tensile shear and bending properties using Kawabata tester's. KES- FB1and KES- FB2. The effect of various fabric structural parameters on fabric low stress mechanical properties was studied. The fabric shear rigidity, bending rigidity, shear hysteresis, bending hysteresis, and tensile linearity were positively correlated with the fabric GSM, thickness, and tightness factor and negatively correlated with fabric linear Stitch modulus, areal stitch modulus, volume stitch modulus, and porosity. The fabric tensile elongation was positively correlated with the fabric linear stitch modulus, areal stitch modulus, volume Stitch modulus, and porosity and negatively correlated with the fabric GSM, thickness, and fabric tightness factor. The above properties were higher in course direction than in wale direction. Separate prediction equations were developed for fabric low stress mechanical properties from Tightness factor, Volume Stitch modulus, and Porosity

Shearing Deformation Research on Annular Woven Shaped Fabrics

shaped weaving is a method which using unequal length of the warp and weft to weave shaped fabrics on the ordinary weaving frames. After multi-layer wound and resin solidified, these shaped fabrics can be formed into whole three-dimensional preform parts, such as oval-shaped pressure vessels, conical tube, ring, etc. because the batch roller on frame is cone frustum, not cylinder, which makes the shear deformation happens when tuck-in fabrics. In this paper, through the establishment of shear deformation model of the annular shaped woven fabric, and theoretical derivation on shear deformation, then calculate the weft deformation angle by theoretical formula. By contrast, we found the calculated shear deformation angle is very near to that measured on the shape fabrics. This proves the shear deformation model and theoretical derivation are correct, accord with the real situation of the shear deformation. Key words: shape woven fabric, shear deformation, theory model,shear angle