scholarly journals Prediction of Fabric porosity from Yarn Diameter and effect of different spinning techniques and process on porosity

Author(s):  
Nusrat Bibi ◽  
M. Umar Abdullah Makhdoom
Keyword(s):  
2019 ◽  
Vol 3 (2) ◽  
pp. 35 ◽  
Author(s):  
Miguel Reis Silva ◽  
António M. Pereira ◽  
Nuno Alves ◽  
Gonçalo Mateus ◽  
Artur Mateus ◽  
...  

This work presents an innovative system that allows the oriented deposition of continuous fibers or long fibers, pre-impregnated or not, in a thermoplastic matrix. This system is used in an integrated way with the filamentary fusion additive manufacturing technology and allows a localized and oriented reinforcement of polymer components for advanced engineering applications at a low cost. To demonstrate the capabilities of the developed system, composite components of thermoplastic matrix (polyamide) reinforced with pre-impregnated long carbon fiber (carbon + polyamide), 1 K and 3 K, were processed and their tensile and flexural strength evaluated. It was demonstrated that the tensile strength value depends on the density of carbon fibers present in the composite, and that with the passage of 2 to 4 layers of fibers, an increase in breaking strength was obtained of about 366% and 325% for the 3 K and 1 K yarns, respectively. The increase of the fiber yarn diameter leads to higher values of tensile strength of the composite. The obtained standard deviation reveals that the deposition process gives rise to components with anisotropic mechanical properties and the need to optimize the processing parameters, especially those that lead to an increase in adhesion between deposited layers.


2017 ◽  
Vol 88 (24) ◽  
pp. 2810-2824 ◽  
Author(s):  
Ning Jiang ◽  
Hong Hu

Textile structures with negative Poisson’s ratio (PR) behavior are called auxetic textile structures. They have received increasing attention in recent years and have been designed and fabricated through spinning, knitting, weaving and non-woven methods. However, auxetic textile structures fabricated using braiding method have not been reported so far. This paper reported a novel type of auxetic braided structure based on a helical structural arrangement. The geometry of the structure and its deformation mechanism were first introduced and described. Then a special manufacturing process was developed by the modification of commonly used tubular braiding technology. Various auxetic braids were fabricated with different structural parameters and yarns and tested under uniaxial extension conditions. The results showed that all manufactured braids exhibited high negative PR behavior and maintained this behavior until the fracture of the component wrap yarn. Among three structural parameters discussed, namely wrap angle, braiding angle and braiding yarn diameter, the wrap angle had more effects on the tensile properties of auxetic braided structure than the other two parameters. The success of fabricating auxetic braids with commercially available yarns in this study provides an alternative way to manufacture auxetics from positive PR materials.


2022 ◽  
Author(s):  
BELETE BAYE Gelaw ◽  
Tamrat Tesfaye ◽  
Esubalew Kasaew

Abstract Decreasing waste materials through recycle has in the recent contributed to sustainable manufacturing in many textile industries for better resource utilization in textile mills. This has been given first priority in manufacturing, processing and finishing operations. Most of the time the yarn manufacturing and proper utilization of this material didn’t give attention in most companies. Especially yarn length variation of packages, weaving beams and copes have very critical impact on those companies which manufacture and utilize yarn products. This variation problem has great impact on their productivity and profitability. This paper describes the application of a new formula in the yarn packaging process and it is accomplished by derivation a new formula that can determine the radius of any package. The formula has integrated the basic characteristics of yarn and fiber including yarn diameter, yarn/ fiber density and mass of the yarn coiled on the cop. Finally we have concluded that package radius is the quadratic function of yarn density and package mass on the cope.


2014 ◽  
Vol 84 (18) ◽  
pp. 1948-1960 ◽  
Author(s):  
Mohamed Eldessouki ◽  
Sayed Ibrahim ◽  
Jiři Militky

The yarn diameter is an effective property in determining fabric structure and processing settings. There are different systems of measuring the yarn diameter; among them is the image analysis of the yarn’s microscopic images. This method is considered to be more precise than other methods, but it is “static” in nature as it measures the property at scattered intervals and does not reflect the continuous variation of the yarn diameter. The goal of the current work is to measure the yarn diameter and its variation over a long length of yarn at fixed intervals to consider the “dynamic” change in the property. To achieve this goal, a high-speed camera (HSC) with a proper magnification was used to capture the images of the yarn and a new robust algorithm was developed to analyze the massive amount of yarn pictures in a reasonable time. The collected data for the yarn diameter were analyzed and compared to the results of the commercial Uster Evenness Tester IV. The results of the HSC were very comparable to the results of Uster and they were able to detect the short-term, the long-term, and the periodic variation of the yarn diameter.


2009 ◽  
Vol 100 (2) ◽  
pp. 158-164 ◽  
Author(s):  
Mounir Jaouadi ◽  
Slah Msahli ◽  
Faouzi Sakli
Keyword(s):  

2017 ◽  
Vol 88 (14) ◽  
pp. 1628-1640 ◽  
Author(s):  
Tong Zhao ◽  
Hairu Long ◽  
Tianqi Yang ◽  
Yanping Liu

Three-dimensional spacer fabrics which have a sandwich structure are formed in a single knitting process without any additional joining treatment. They consist of two separate multifilament outer layers connected by arrays of spacer monofilaments. This paper presents an experimental study on the relationships between the cushioning properties and structural parameters of weft-knitted spacer fabrics in order to lay a foundation for the development of seamless shaped impact protectors for human body impact protection. Sixteen spacer fabrics of different structural parameters were knitted on a computerized flat knitting machine and tested on a universal mechanical testing machine. The cushioning properties of the spacer fabrics were analyzed in terms of their structural features, compression stress–strain curves, energy absorption, and compression resilience. It was found that multifilament fineness, spacer yarn diameter, and spacer yarn pattern should be matching in order to form effective binding structures between the outer layers and spacer monofilaments. The results also showed that spacer fabrics knitted with a shorter spacer yarn span distance, coarser monofilaments, and higher spacer yarn density have better compression resistance and absorption energy but inferior compression resilience if their binding structures are effective. This study has practical significance in promoting the application of this type of fabric as a cushion material for human body protection.


e-Polymers ◽  
2017 ◽  
Vol 17 (3) ◽  
pp. 221-226 ◽  
Author(s):  
Chaojing Li ◽  
Xiaoming Wang ◽  
Fan Zhao ◽  
Fujun Wang ◽  
Zou Ting ◽  
...  

AbstractTubular braiding fabric is widely used in developing tissue-engineered scaffolds, and is especially suitable for connective tissues like ligaments and tendons. The pore size and porosity of braiding structure scaffolds not only highly affect cell adhesion and proliferation, but also influence the mechanical behavior of those scaffolds. It is important to develop braiding scaffolds with controllable pore size and distribution. The purpose of this work is to add insight to the mechanics of this passive pore structure control system. Thus, some constitutive equations were established to reveal the relationship between braiding technical parameters (including the number of spindles, braiding structure, cylindrical mandrel radius, and yarn diameter) and the pore size, the porosity of tubular braiding fabric by the mathematical modeling method. Through this model, pore size and the porosity of the tubular braiding scaffold can be precisely controlled by quantitatively adjusting braiding technical parameters. Furthermore, the reliability and accuracy of this model were verified by the experimental data.


2008 ◽  
Vol 33-37 ◽  
pp. 477-482 ◽  
Author(s):  
Xi Tao Zheng ◽  
Jian Feng Zhang ◽  
Fan Yang ◽  
Ya Nan Chai ◽  
Ye Li

To quantify the effect of structural through-thickness reinforcement in foam core sandwich composite panels, an experimental study was carried out which included three-point bending tests, core shear tests, flatwise tensile and compression tests, as well as edgewise compression tests. Standard test procedures based on ASTM guidelines are followed to test the behavior of the stitched panels with reinforcement at 90 degree orientation with respect to the sandwich faces. The test specimens were manufactured by using polyurethane foam Rohacell 71 IG and carbon fiber reinforced composite facesheets. The dry perform facesheets and foam core were then assembled in a dry lay-up already stitched. Kevlar 29 yarn was used to stitch both sets of panels. The results showed a significant effect of the stitching on the in-plane Young’s modulus which was attributed to local displacements of the in-plane fibers and changes in the fiber volume fraction. Stitching of sandwich panels significantly increases the maximum failure loads under flexure, core shear, flatwise tensile, flatwise compression, and edgewise compression loading. A finite element based unit-cell model was developed to estimate the elastic constants of structurally stitched foam core sandwich composite panels taking into consideration the yarn diameter, the stitching pattern and direction as well as the load direction. Depending on these parameters, local changes of the fiber volume fraction as well as regions with undisturbed and disturbed fiber orientations within the laminate plies are taken into account. A good match between the finite element modeling and the experimental data was obtained. The present work should be considered as a step towards developing a more sophisticated numerical model capable of describing mechanical behavior of sandwich structures.


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