Woven fabrics mechanical properties

De Jong, S. and Postle, R. An Energy Analysis of Woven-Fabric Mechanics by Mean of Optimal-Control Theory Part 1 Tensile Properties. J. Text. Inst., 68, 350-361 (1977). 

Drape of woven fabrics induced by gravitational force is influenced by a combination of certain deformation properties and structural characteristics. Stiffness, shear and extension are the relevant measure of deformation, while fabric weight and thickness are the appropriate structural characteristics. The type of woven construction (for example, plain, matt, twill, satin) is also a factor influencing the drape of woven fabric. Many researchers tried to find out the relationship between the fabric drape behaviors with the fabric mechanical properties. A brief of their findings are discussed below. 

Commercially available membranes are usually reinforced with woven, synthetic fabrics to improve the mechanical properties. Several hundred thousand square meters of IX membranes are now produced aimuaHy, and the mechanical and electrochemical properties are varied by the manufacturers to suit the proposed appHcations. The electrochemical properties of most importance for ED are (/) the electrical resistance per unit area of membrane (2) the ion transport number, related to current efficiency (2) the electrical water transport, related to process efficiency and (4) the back-diffusion, also related to process efficiency. 

As with tissue, woven glass cloth is used for decorative or acoustic purposes. Additionally, close-woven fabrics give improved fire-safety properties and are resistant to mechanical abuse. Glass cloth or scrim of an extremely open weave is used on insulants as a key for mastic or hard-setting finishes. 

Commercial membranes are usually reinforced with woven, synthetic fabrics to improve the mechanical properties. Several hundred thousand... 

Different yarns of different physical and mechanical properties can be woven into the same fabric by adding creel behind the weaving machine or by adjusting filling yarn feeders. 

The key fibre property that determines pill loss is the flex life of the anchor fibres. The higher the flex life, the longer the pill remains on the fabric surface. The specific details of these curves depend on fabric and yam characteristics as well as on the particular mechanical forces acting on the fabric. The pill curves for a knit and a woven fabric made from the same polyester yams are shown in Fig. 11.3. 

Table I shows the mechanical properties of the carbon fiber-reinforced PTFE (PTFE composite non-crosslinked) and the carbon fiber-reinforced PTFE with fluorinated-pitch (PTFE / FP composite thermo-chemical crosslinked). For the tensile test with a direction of 45 ° for plane-woven carbon fabric, the tensile strength of the PTFE / FP composite was about 2.3 times higher than that of the non-crosslinked PTFE composite. Moreover, the Young s modulus of the crosslinked composite was about 2.6 times higher than that of the PTFE composite. The tensile strength and Young s modulus are results of 0 ° or 90 ° direction for the fabric reflected the carbon fiber strength and the modulus.

Harpa, R., Piroi, C., Cristian, I., 2008. In Study Regarding the Physical—Mechanical Properties of Coton/Amicor Woven Fabrics for Medical Use., ITC and DC Book of Proceedings of the 4th International Textile, Clothing and Design Conference — Magic World of Textiles, pp. 769-774. 

Fabrics woven from Kevlar 49 aramid fiber are often used as composite reinforcement, since fabrics offer biaxial strength and stiffness in a single ply. The mechanical properties of Kevlar 49 aramid are dependent on the fabric constmction. The composite properties are functions of the fabric weave and the fiber volume fraction (typically 50%-55% with ply thickness 5-10 mils, depending on fabric constmction). In 1987, Du Pont introduced high-modulus Kevlar 149. Compared to Kevlar 49 it has higher performance (47% modulus increase) and lower dielectric properties (65% decrease in moisture regain). 

All these mechanical results demonstrate the ability of 3D woven fabrics to be adjusted to requirements and cover a wide range of mechanical properties by modifying weaving or manufacturing parameters such as spacing between yams or fibre volume fraction of the composite. Databases of materials can be built in order to help design or selection of these 3D textile reinforced composites. 

Most carbon fibre reinforced plastics (CFRP) used and investigated to date are produced from preimpregnated continuous carbon fibre prepregs. Polymers reinforced with aligned short carbon fibres have certain advantages as materials for structural components, because they can easily be formed into complicated shapes with satisfactory mechanical properties. Woven fabrics produced from carbon fibres find increasing application in the aerospace and many other industries, because they are easy to handle, they have the ability to conform to complicated shapes and the in-plane properties are more isotropic than those of equivalent unidirectional materials. 

In this study the yam pullout test is applied to investigate internal mechanical properties of the plain woven fabrics. In the first step an analytical model was developed, inputs of which employs simple mechanical properties such as the fabric modtrlus, the weave angle, and the fabric deformation angles during the pullout test. This model predicts important mechanical parameters such as the weave angle variations, the yam-to-yam friction coefficient, the normal load in crossovers, the lateral forces, and the opposed yam strain within the fabric. This approach may be extended to other types of the woven fabrics. 

Acceptable agreement between the experimental and the theoretical resrrlts reveals that the reported can predict the yam pullout behavior to an admissible extent. Besides, it proves that the equations of the force balance method are snitable enongh to be used for determining some important stractural and mechanical properties of the woven fabrics. Simplicity of the model principals and the few nnmbers of the experimentally required factors are the main achievements of this model. 

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