Weave Density Research Articles

The Analysis of Vibration Resistance of the Shape and Braided Laminated Manufactured Structure Using Taguchi Method

In this study, the L934 orthogonal table of the Taguchi method is used as a systematic parameter analysis. A rapid prototyping machine (RPM, manufactured by the research team) and fused deposition modeling (FDM) are used to make anti-vibration test specimens and to analyze the effect of different process parameters, such as weaving and shaping, on vibration resistance. Hopefully, various application fields will be extended via the deposition method. The impact test is executed by dropping a steel ball onto each test piece which is connected to an accelerometer and a PW700 spectrometer for extracting the frequency response during the impact. The vibration performance under different process parameters is analyzed. Several parameters that may affect anti-vibration performance are selected under the existing process, namely weaving method (A), deposition thickness (B), weaving density (C) and cross weaving per n-layer (D). The policy is to evaluate the required time period to restore to the steady state after impact. Hence, the shorter the convergence time is, the better the specimen resists the vibration. The experimental results show that the build-up layer thickness and the weaving density are the main control factors that affect the anti-vibration ability most. The process parameter A3B1C1D2 obtains the best vibration resistance performance.

Archaeology and Hauntology: An Ongoing, Stalled Conversation

It is certainly possible that we might learn to better acknowledge the spirits of our ancestors who came before us, as well as to recognize them in such ways that we also learn to embrace the ‘woven density’ of our own lives, our histories and our communities. By doing so, we might begin to discover that the spirits we had thought were removed from our modern, secularized world never fully left us, just as the irrationality of our humanity cannot be fully tamed via a reductive, rational and scientific outlook on life. There are, as Bruno Latour had frequently argued, many modes of human existence that interact in complex networks of relations. To fall back on any one particular mode as if it could dominate over others would only grant us a mistaken impression of our own humanity, even though this is what has been practiced for centuries in order to legitimate a particular, sovereign configuration of power. It is to the credit of archaeologists and hauntologists alike that we are more able than ever to take account of the complexity of ourselves in ways that we had previously ignored or repressed.

Variable density points pressure sensor with wide sensing range and spatial pressure mapping

Wearable flexible pressure sensors are a novel class of human activity detection device. However, the preparation of pressure sensors with high sensitivity and wide sensing range still faces great challenges. This study reveals an flexible heat-resistant variable density point pressure sensing array (PSA) with ultra-wide sensing range based on Ti3C2Tx-MXene. MXene containing polar oxygen-containing functional groups coated polyester fiber fabricated the pressure sensing layer while a stainless steel wire core is used as a flexible electrode for signal collection. The signal processing device rapidly converts the mechanical signal into electrical signal output to increase the transmission speed and range. Experimental results show that the PSA can effectively sense dynamic and static pressures with high sensitivity (0.14–0.87 kPa−1 over a pressure range of 7.2 Pa–2000 kPa), a wide sensing range (0–15000 kPa), fast response time (80 ms), 10,000 cycles (2000 kPa) stability and maintains a 81.25% current response. The noval fully woven structural flexible PSA exhibited larger area, of which the weave density is varied to control resolution and the pressure mapping is referenced to each pixel point to qualitatively and quantitatively analyze shape and pressure distribution. Variable density points pressure sensor with wide sensing range and spatial pressure mappinghas promising applications in healthcare.

Optimization of Uniaxial Tensile Stress-Strain Response of 3D Angle Interlock Woven Fabric Composite using Weft Density and Draw-In Plan Variables

Currently, 2D woven composites are extensively incorporated into a variety of technical automotive body parts and protective body armor owing to their excellent fabric strength performance. However, there is still a lack of attempts to utilize 3D woven fabrics for the same technical application. Hence, it is vital to examine the fundamental tensile strength of woven fabric composite materials when determining their suitability for end-use applications. This study aimed to investigate the novel effects of two parameters on the uniaxial tensile strength of a high-tenacity polyester three-layer 3D angle interlock (3DAI) woven fabric composite, namely, weave drafting draw-in insertion and weave density. Four different drafting patterns were considered: pointed (DRW 1), broken (DRW 2), broken mirror (DRW 3), and straight (DRW 4), for weft density at 14 and 25 pick.cm-1. Samples of the 3DAI woven fabric reinforced with epoxy composite at different drafting patterns and weft density combinations were produced and tested. Consequently, the maximum tensile stress and strain were recorded in the woven fabric composite sample with DRW 4 and 25 pick.cm-1 at 113 MPa and 11%, respectively. The study shows that different weft densities and draw-in plan settings play a significant role in the tensile strength performance of the 3DAI woven composite.

Prediction of optimum alkaline hydrolysis conditions for imparting superhydrophobicity to large-area fabrics using three-dimensional modeling

This study proposes a fabric-specific alkaline hydrolysis method to impart stable water repellency to large-area polyester fabrics, regardless of yarn type or weave pattern. The geometries of 120 virtual fabrics with varying yarn properties, weave patterns, and weave densities are modeled, and their surface-etching efficiency and superhydrophobicity are predicted. While the alkaline hydrolysis-derived nano-structuring efficiencies of fabrics are predicted based on the Kallay and Grancaric model (1990) with changes to reflect the fiber volume fraction F as a major variable for fabric structures. For predicting superhydrophobicity, the fabric meso-structure contact angle is calculated based on the Michielsen and Lee model (2007); the fixed yarn distance used in the original model is replaced by the simulated inter-yarn porosity P to exclude error caused by structural variability. The final virtual fabric contact angle is predicted reflecting the effect of nano-roughness, which is validated by comparing the predicted contact angle with a physical sample having identical geometries. The contact angle of any fabric can be predicted using structural simulation, given the alkaline treatment conditions are adjusted according to the unique geometry of each fabric to express superhydrophobicity. Moreover, even for samples with low predictive contact angles, superhydrophobicity can be achieved by maximizing the effect of the nanostructure through strong alkaline treatment. An ISO 5 water repellency is achieved for all large-area polyester fabrics.

Active Textile Fabrics from Weaving Liquid Crystalline Elastomer Filaments.

Active fabrics, responding autonomously to environmental changes, are the "Holy Grail" of the development of smart textiles. Liquid crystal elastomers (LCEs) promise to be the base materials for large-stroke reversible actuation. The mechanical behavior of LCEs matches almost exactly the human muscle. Yet, it has not beenpossible to produce filaments from LCEs that will be suitable for standard textile production methods, such as weaving. Based on the recent development of LCE fibers, here, the crafting of active fabrics incorporating LCE yarn, woven on a standard loom, giving control over the weave density and structure, is presented. Two types of LCE yarns (soft and stiff) and their incorporation into several weaving patterns are tested, and the "champions" identified: the twill pattern with stiffer LCE yarn that shows the greatest blocking force of 1-2Ncm-1 , and the weft rib pattern with over 10% reversible actuation strain on repeated heating cycles. Reversible 3D shape changes of active fabric utilize the circular weaving patterns that lead to cone shapes upon heating. The seamless combination of active LCE yarns into the rich portfolio of existing passive yarns can be transformative in creating new stimuli-responsive actuating textiles.

Investigation of flow and pressure drop through porous metallic screens with different weave densities

Metallic screens have been frequently used for cryogenic propellant management system under microgravity conditions due to the superior properties to separate the liquid and vapor phases. The flow through screens (FTS) characteristics as the main factor to determine the separation performance is greatly influenced by the pore structure of metallic screens. However, the actual flow behavior through the pore structure cannot be readily observed by the experiments and macroscopic simulation. Therefore, in the present study, three-dimensional pore-scale models are established to investigate flow behavior through the pore structure, and meanwhile the FTS characteristics for four of types Dutch Twill Weave (DTW) screens with different weave densities are presented. The influence of cryogenic temperature on the volume porosity and specific surface area of the metallic screens with different weave densities are firstly examined based on periodic structure unit for accurate estimation in the following study. Based on the pore-scale model, numerical simulations of laminar flow through screens for various liquid are carried out, and the accuracy of the model is verified by comparing to the experimental results. The simulation results show that the cross-sectional hydraulic diameter of the screen in the thickness direction imposes a significant effect on local FTS pressure drop. Moreover, the dimensionless correlations of the FTS pressure drop for the DTW screens are obtained based on the simulation results. Furthermore, the permeability and Forchheimer coefficient of the screen are acquired on the basis of the Darcy-Forchheimer law for facilitating the design of Liquid Acquisition Device (LAD).

Effect of the Geometrical Structure on the Superhydrophobicity and Self-Cleaning Properties of Plasma-Treated Polyvinylidene Fluoride Fabrics.

The purpose of this study is to develop superhydrophobic polyvinylidene fluoride (PVDF) fabrics to increase their water repellency and self-cleaning properties and to investigate the effects of the inherent fabric roughness on these properties. A PVDF fabric, composed entirely of electrospun PVDF filament yarns, and two PVDF/polyester (PET) fabrics with different weave densities are used. After treatment with O2 plasma for 12 min and CF4 plasma for 4 min, superhydrophobicity is achieved in all fabrics, resulting in an increase in water repellency and self-cleaning efficiency. The PVDF fabric with the lowest shedding angle exhibits the most pronounced droplet rebound behavior and the highest self-cleaning efficiency. Increases in surface inclination angle and droplet volume and a decrease in the drop fall height all contribute to conditions more favorable for water droplet repellency. The self-cleaning efficiencies of the plasma-treated PVDF fabric and high-density PVDF/PET fabric are higher for hydrophilic dust, in contrast to those of the untreated ones. The findings of this study are expected to enable the design of weaving or nano-structuring conditions that enhance the water repellency and self-cleaning properties of PVDF fabrics, for the development of stable energy-harvesting smart textiles.

Effect of cotton fabric properties on fiber release and marine biodegradation

The effects of cotton fabric structure and finishing on fiber emissions during washing and degradation were studied. Fabrics with different combinations of yarn count, weave structure, or weave density, and the fabrics dyed, water-repellent or peach skin finished were prepared. Significant fabric structural factors and resultant physical properties influencing the fiber release were statistically driven. The results showed that, on average, 16 wt% of the fibers was filtered through a washing machine, and the filtration rate increased when the discharged fibers were on average longer. It was found that the cotton fabric with a higher yarn count or weave density and more compact weave structure released a lesser amount of fibers and that their average length tended to be shorter. Compared to the untreated fabric, the fabric with peach skin finish released more fibers and the average fiber length was longer, whereas the fabric with water-repellent finish released fewer fibers that had a shorter length. It was demonstrated that cotton fiber emission could be reduced when the fabric had a larger weave parameter, low fuzziness, high abrasion resistance, and low water absorbency. Cotton fibers submerged in seawater exhibited a lower primary degradation than that of fibers buried in soil. In addition, the cotton fibers submerged in seawater maintained at 7°C exhibited a lower biodegradability than that of fibers submerged in seawater at 20°C. Moreover, in seawater, water-repellent fabric was biodegraded less than untreated fabric.

Water Repellency/Proof/Vapor Permeability Characteristics of Coated and Laminated Breathable Fabrics for Outdoor Clothing

This study examined the water repellency (WR), waterproof, and water vapor permeability (WVP) characteristics of twelve types of laminated and coated woven fabrics for outdoor clothing. These characteristics were compared with the fabric structural parameters, such as cover factor, thickness, and weight, and surface modification (finishing) factors, such as coating, laminating, and Teflon treatments. In addition, an eco-friendly process for surface modification was proposed followed by a summary. Superior waterproof-breathable characteristics with 100% water-repellency were achieved in specimen 3 in group A by treatment with a hydrophilic laminated finish using nylon woven fabric with a cover factor between 0.7 and 0.9 in a 2.5-layered fabric, which was the best specimen with waterproof-breathable characteristics. A high WVP in the coated and laminated fabrics was observed in the fabrics with a low weave density coefficient (WDC) and low thickness per unit weight of the fabric, whereas superior water repellency and waterproof characteristics were observed in the high-cover-factor (WDC) fabric with appropriate fabric thickness. The determination coefficient (R2) from regression analysis between the WVP and fabric structural parameters indicated a higher contribution of the fabric structural parameters than surface modification factors, such as coating and laminating to the WVP in the coated and laminated fabrics. Furthermore, the cover factor was the most important factor influencing the WVP of the waterproof-breathable fabrics. Of twelve coated and laminated fabrics, the laminated nylon and nylon/cotton composite fabrics showed superior WVP with high WR and waterproof characteristics. Accordingly, based on the WR, waterproof, and WVP characteristics of the coated and laminated breathable fabrics, the laminating method, as an eco-friendly process, is recommended to obtain better waterproof-breathable fabrics.

Cryogenic wicking of liquid nitrogen in the metallic screens with different weave densities

Liquid wicking in porous media has been applied to the management and transportation of propellant in microgravity. The flow and heat transfer characteristics during wicking of cryogenic fluid in the metallic screens play significant roles in determining the wicking performance. However, the experimental investigations of cryogenic wicking are relatively rare due to experimental difficulties. In the present study, the experimental visualization of wicking of liquid nitrogen is carried out, where five typical Dutch Twill Weaves (DTW) with different weave densities are employed as the test samples. The evolutions of the wicking front during cryogenic wicking are experimentally traced. Moreover, the cryogenic wicking in the DTW has been numerically investigated by considering the thermal non-equilibrium equation in the porous media, which yields a good agreement between the experimental and numerical results due to better accounting the evaporation of liquid nitrogen resulted from the heat conduction of the DTW. As an example, the wicking height of liquid nitrogen in the DTW 200 × 1400 reaches a maximum wicking height of about 0.0851 m, which is improved by about 36.4% ∼ 75.0% compared to the results in the literature. Furthermore, the effect of the weave densities of the DTWs on the flow and heat transfer characteristics are investigated, which provides useful information for the screen channel liquid acquisition device of cryogenic propellant.

Liquid wicking flow characteristics in metallic screens with various weave densities

Liquid wicking flow characteristics in metallic screens with various weave densities

The Mechanistic role in production linen fabric using different Piqué Technique.

Each fabric material has its unique existence; for instance, the Linen fabric is popular not only for its attractive appearance and rich history but also the manufacture of this fabric is characterized by complicated interlacing techniques to shows its splendor. When it comes to varieties of piqué technique to production most linen fabric in markets, it is worth understanding about realizing process owing to a decade's worth of learning from its manufacturing experience. This study intends to analyze the respective effect of the mechanistic role at weaving machines as shed angle, warp tension and weave density with different pique techniques on Linen fabrics propriety. It is founded that Clear Positive and Opposite relationships between measured parameter give clear judgment for assessing the behavior of blended linen fabrics for textile manufacturers in terms of mechanical and physical properties with customer satisfaction is intended; as well as an indicator for reasoning cluster of excellence integrative production and economical aspects, which is a factor in markets

Determining the visual Impression of cotton fabrics while Rotating.

In order to identify the light reflectance from cotton fabrics produced from various (spun yarn., ( carded – open end ) ,an attempted measured Light reflectance distribution (CIELAB L*) by using a (GCMS-4 Gonio)-( Spectrophotometric color measurement system) at various Illumination angle (θi) and Viewing angle(θv) with turning point(θw) from ( 0-90)o in both direction .Results clarify the relations between the distribution pattern (L*) with fabrics made from different spun yarn which had an effect for fabrics on visual sense of hymen and indicate more about aesthetics of cotton fabric while rotating. Therefore, the results indicate that L* reflectance measurement for cotton woven fabric shows that lightness values depended on method of spinning but in closer values, weave density also give parameter in light reflectance from woven fabric in weft direction , Illumination angle and Viewing angle also indicate an important parameter for visual sense from fabrics and its related to aesthetic properties. In shorts: (θw) was found to be the most accurate parameter for determining the change of lightness from shiny to dull in visual assessment for cotton woven fabrics.

Development of Energy-Efficient Superhydrophobic Polypropylene Fabric by Oxygen Plasma Etching and Thermal Aging.

This study developed a human-friendly energy-efficient superhydrophobic polypropylene (PP) fabric by oxygen plasma etching and short-term thermal aging without additional chemicals. The effect of the microroughness on the superhydrophobicity was examined by adjusting the weave density. After the PP fabric was treated with oxygen plasma etching for 15 min and thermal aging at 120 °C for 1 h (E15H120 1 h), the static contact and shedding angles were 162.7° ± 2.4° and 5.2° ± 0.7° and the energy consumption was 136.4 ± 7.0 Wh. Oxygen plasma etching for 15 min and thermal aging at 120 °C for 24 h (E15H120 24 h) resulted in a static contact and shedding angle of 180.0° ± 0.0° and 1.8° ± 0.2° and energy consumption of 3628.5 ± 82.6 Wh. E15H120 1 h showed a lower shedding angle but had a higher sliding angle of 90°. E15H120 24 h exhibited shedding and sliding angles of less than 10°. Regardless of the thermal aging time, superhydrophobicity was higher in high-density fabrics than in low-density fabrics. The superhydrophobic PP fabric had a similar water vapor transmission rate and air permeability with the untreated PP fabric, and it showed a self-heading property after washing followed by tumble drying and hot pressing.

Predicting air permeability of multifilament polyester woven fabrics using developed fuzzy logic model

The number of filaments in yarn cross-section, weave density, and weave type are considered the most important factors that affect the property of air permeability of multifilament woven fabrics. Microfilament yarns significantly affect the air permeability property of this type of fabric because of the low porosity between the filaments. This study deals with the development of a fuzzy logic model for predicting the air permeability of multifilament polyester woven fabrics produced from conventional and microfilament yarns. The polyester multifilament yarns used in this study were produced with three different microfilament fineness and two conventional filament fineness levels. The woven fabric samples used in this study were obtained in three weave types: plain, twill, and satin, and with five different weave densities. In accordance with the experimental test results, both regression analysis and fuzzy logic system were built. The air permeability results generated from the developed fuzzy model and the regression equations were compared with the experimental values. Satisfactory and accurate prediction results were obtained with the developed fuzzy logic model. The mean absolute error of the fuzzy model and regression analysis were found to be 2.32%, 12.59%, respectively. Therefore, it was confirmed that the fuzzy model was superior in predicting air permeability.

Aerosol Filtration Efficiency of Common Fabrics Used in Respiratory Cloth Masks.

The emergence of a pandemic affecting the respiratory system can result in a significant demand for face masks. This includes the use of cloth masks by large sections of the public, as can be seen during the current global spread of COVID-19. However, there is limited knowledge available on the performance of various commonly available fabrics used in cloth masks. Importantly, there is a need to evaluate filtration efficiencies as a function of aerosol particulate sizes in the 10 nm to 10 μm range, which is particularly relevant for respiratory virus transmission. We have carried out these studies for several common fabrics including cotton, silk, chiffon, flannel, various synthetics, and their combinations. Although the filtration efficiencies for various fabrics when a single layer was used ranged from 5 to 80% and 5 to 95% for particle sizes of <300 nm and >300 nm, respectively, the efficiencies improved when multiple layers were used and when using a specific combination of different fabrics. Filtration efficiencies of the hybrids (such as cotton–silk, cotton–chiffon, cotton–flannel) was >80% (for particles <300 nm) and >90% (for particles >300 nm). We speculate that the enhanced performance of the hybrids is likely due to the combined effect of mechanical and electrostatic-based filtration. Cotton, the most widely used material for cloth masks performs better at higher weave densities (i.e., thread count) and can make a significant difference in filtration efficiencies. Our studies also imply that gaps (as caused by an improper fit of the mask) can result in over a 60% decrease in the filtration efficiency, implying the need for future cloth mask design studies to take into account issues of “fit” and leakage, while allowing the exhaled air to vent efficiently. Overall, we find that combinations of various commonly available fabrics used in cloth masks can potentially provide significant protection against the transmission of aerosol particles.

Influence of fabric architecture on energy absorption efficiency of soft armour panel under ballistic impact

This study aims to optimize fabric architecture of soft armour panel in order to improve ballistic performance without increasing weight. Finite Element (FE) analysis, in conjunction of ballistic test, was used to investigate ballistic responses of fabrics with different weave parameters under ballistic impact. In an individual layer, the yarn crimp effect on energy absorption exhibits significant in the consideration of yarn count, weave density and areal density of fabric. FE results indicate that the stress on the high crimp fabric fluctuated more severely at the crossover and fail earlier than that of the fabric with low crimp. In a multi-layer panel, the yarn crimp is still influential on energy absorption of each fabric layer, Backface Signature (BFS) and perforation ratio of the whole panel. The panel combining low crimp fabrics shows that the energy absorption efficiency of each layer is higher than that of the panel composed of high crimp fabrics. However, the panel with low crimp fabrics possesses enlarged BFS and increased perforation ratio. These findings are greatly meaningful for the design of soft armour panel.

Contribution of constituent yarns of the worsted woven fabrics in various directions during the tensile loading

Despite the fact that tensile behavior of woven fabrics has been previously explored, the nonisotropic material qualities of fabrics can be considered from various points of view. From this perspective, this study is carried out to comprehensively inspect the tensile behavior of woven fabrics. Since worsted fabrics are considered in outwear clothing and their extension under low loads determines their shaping on the body, the extension behavior of the worsted woven fabrics in various directions was probed thoroughly. It was found that fabric stress variations in terms of time in all directions trace in a parabolic manner but the shape of the curve (open or close form) depends on the fabric direction. The above mentioned phenomenon is related to weft and warp yarn crimps and their contribution to tolerating the tensile load. In all fabric directions, it is possible to identify the tensile behavior index, which is the time of change in the fabric’s tensile behavior. The value of tensile behavior index against fabric direction follows a sinusoidal function, and it is affected by fabric weave structure and density.

Finite Element Study on the Influence of Structural Parameters on the Ballistic Performance of 3D Networked Fabrics

Networked fabrics are a type of three-dimensional multilayer fabrics having predetermined interconnections between layers by combining yarns from two adjacent sublayers into one. This paper reports the research on the influence of structural parameters on the ballistic performance of networked fabrics using finite element analysis in parallel with experiment. The widths of separate and combined sections are found to affect the energy absorption (EA) of regular networked fabrics against high-velocity impact. Separate sections of networked fabrics generally outperform combined sections. The optimal width of the separate section is around 9.5 cm for both dense and loose networked fabrics when impacted at the separate section. The optimal width of combined section decreases from 2.38 cm to 1.15 cm with the decrease of weave density in this area. For the studied structural parameters, highest EAs of dense and loose networked fabrics are around 13.3% and 17.1% higher than those of their counterpart layups of dense and loose plain-woven fabrics, respectively. These findings suggest networked fabrics could be engineered to improve the ballistic performance of flexible fabrics.