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The interlaminar strength and designability of three-dimensional shallow straight-joint woven fabrics make them a promising material for personal protective armor. This study investigated the influence of clamping methods on the ballistic mechanism of three-dimensional shallow straight-joint woven fabrics. The study used a mesoscopic yarn-level full-size model developed based on the finite element method to analyze the energy absorption patterns, back face deformation, and damage morphology of the three-dimensional shallow straight-joint woven fabrics under different clamping methods. The results show that the clamping method has a significant influence on the ballistic performance of the fabric. With the weft-sides clamped, its ballistic limit velocity and failure morphology are similar to four-sides clamping, with more negligible energy absorption and failure area. Warp-sides clamped is second, while the corner held undergoes the maximum out-of-plane displacement and energy absorption, exhibiting an utterly different failure mechanism. This study shows that the clamping method of a fabric affects its ballistic performance through interaction with the fabric's internal structure. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) woven fabrics have emerged as an effective structure for ballistic protection due to their flexibility, multi-impact resistance, and ability to form complex shapes. However, the influence of different 3D fabric architectures on ballistic performance is not fully understood. This study investigates the ballistic response of three types of 3D angle-interlock woven fabrics (3DTAWF, 3DSSWF, 3DSBWF) using numerical simulations with experimentally validated material models. Full-scale fabric models enable examining the dynamic behavior at the yarn level. Results show 3DSBWF exhibits the best ballistic performance with higher ballistic limit and energy absorption compared to 3DTAWF and 3DSSWF. Damage evolution indicates 3DSBWF and 3DSSWF have better structural integrity during penetration. The higher warp density and straighter warp path contribute to balanced warp-weft energy absorption and improved impact resistance in 3DSBWF. This study elucidates the role of 3D fabric structure on energy absorption patterns and failure morphology. The findings provide valuable insights into 3D woven fabric designs for optimizing ballistic protection performance. [ABSTRACT FROM AUTHOR]

In this research, an investigation was conducted to ascertain the impact of boron carbide (B4C) microparticles on soft and hard armor configurations, utilizing two distinct high‐performance fabrics namely, Kevlar and Ultra‐high Molecular Weight Polyethylene (UHMWPE), also this work discerned the optimal fabric for protection against dagger attacks and 9 mm full metal jacket (FMJ) projectiles. Initially, rheological tests on four shear thickening fluid (STF) samples revealed that 70% of nano‐silicate (SiO2) content was the optimal ratio. Besides, scanning electronic microscope (SEM) tests showed that B4C affected the nano‐silicate dispersion. Hence, the use of STF as a matrix, led to complete protection in low‐velocity stab test and behavior improvement when subjected to NIJ ballistic test for both fabric types. On the other hand, the dynamic mechanical analysis (DMA) of the thermosetting epoxy resin‐based composites reinforced by B4C indicated that the 10% ratio offered maximum rigidity, resulting in improved ballistic performance. This study revealed that Kevlar fabrics exhibit superior behavior in soft protection, while UHMWPE hard composite display further rigidity against high‐velocity impacts. Overall, this work contributes novel insights into the efficiency of B4C integration within soft and hard armor configurations using two ballistic fabrics, highlighting their performance characteristics in ballistic shielding. Highlights: Investigation of B4C microparticles: The research examines the impact of B4C microparticles on soft and hard armor configurations.High‐performance fabrics: Kevlar and UHMWPE uses.The use of STF as a matrix for soft and thermosetting epoxy resin for hard armor: enhanced composite performance.Low‐velocity and high‐velocity impact tests investigations; microparticles B4C incorporation: superior mechanical characteristics.Remarkable energy absorption: promising shielding uses. [ABSTRACT FROM AUTHOR]

The purpose of the research discussed in this article is to explore the possibility of creating hybrid soft ballistic panel (BP) package variants by integrating into their composition layers of graphene-modified para-aramid fabrics in combinations with the different ballistic Kevlar textiles to improve the durability of the first layers of the soft ballistic panel. To address this goal, the liquid-phase exfoliation (LPE) method was used for integrating dispersions into composites to solve a number of topical problems in the stages of the technological sequence development of processing methods and optimizing processing parameters in accordance with the processing specifics of aramid textiles to achieve the desired properties of modified ballistic fabric, including the provision of coating adhesion to the surface to be modified. To test the results, ballistic experiments were performed and the back-face signature (BFS) of bullet impact on a backing material was analysed according to standards. Bullet impacts on the first ballistic protective fabric layers were also studied. [ABSTRACT FROM AUTHOR]

The incorporation of microcapsule particles (MPs) into fabrics offers the potential to enhance both the friction between fabric yarns and the bulletproof impact performance. In this study, MPs were prepared using the interfacial polymerization method. Furthermore, an innovative modification of the AF fabric was achieved by introducing a silane coupling agent and MPs. This resulted in the development of a microcapsules‐aramid fibers (MPs‐AF) composite material exhibiting excellent protective performance. The characterization experiment demonstrated the successful adhesion of MPs to the AF fabric, forming a robust bond between the fiber and the particles. Importantly, the modification process did not have any adverse effects on the fiber structure. The study further investigated the ballistic performance and protection mechanism of the modified fabrics through mechanical performance tests and ballistic impact tests. The yarn pull‐out experiment revealed that the MPs‐AF composite material exhibited a significant increase in pull‐out force, with a remarkable improvement of 175.6% compared to AF fabric. In the ballistic impact experiments, the MPs‐AF composite material demonstrated a substantial increase in ballistic limit velocity, rising from 52 to 118 m/s when compared to the AF fabric. These findings highlight the potential application of the MPs‐AF composite material in the field of wearable protection. Highlights: Fiber surface modification grafting reaction.A simple and novel solution impregnation method was used to prepare modified AF.Preparation of microcapsule particles by interfacial polymerization.Green new fiber bulletproof material.Chemical grafting produces strong chemical bonds to increase interfacial resistance. [ABSTRACT FROM AUTHOR]

This study investigates the influence of various clamping methods on the ballistic performance of 3D shallow bend-joint woven fabrics (3DSBWF). Utilizing a mesoscopic yarn-level full-size model based on the finite element method (FEM), we analyze energy absorption patterns, backface deformation (BFD), and damage morphology under different clamping conditions. The results demonstrate that clamping methods significantly impact the ballistic performance of 3DSBWF. Specifically, fabrics clamped on the weft side exhibited ballistic limit velocities around 170 m/s and failure morphologies similar to four-side clamping, with minimal energy absorption and failure areas accounting for 25% and 15% of the total energy absorbed, respectively. The warp-side clamped scenario, with a ballistic limit velocity of approximately 220 m/s, ranked second in performance, while the corner-held configuration, with the highest ballistic limit velocity of around 260 m/s, experienced the highest out-of-plane displacement and energy absorption (55%), indicating a distinct failure mechanism. This study highlights the critical role of clamping methods in optimizing the design and performance of ballistic protective fabrics. [ABSTRACT FROM AUTHOR]

Copyright of Industria Textila is the property of Institutul National de Cercetare-Dezvoltare pentru Textile si Pielarie and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Though the transition from disposable to reusable surgical gowns holds substantial promise, successful implementation faces challenges. This study investigated tactile and thermophysiological comfort in surgical reusable gowns, comparing them with their disposable counterparts. Parameters such as surface roughness, compression, heat flux, and material rigidity were tested using a Fabric Touch Tester. Additionally, the water vapour permeability and static charge of the gowns were assessed. Thermophysiological comfort of the gowns was evaluated by measuring the temperature and relative humidity (RH) on test subjects during wear trials where they were engaged in an activity that mimics a surgeon's performance. Skin temperature was monitored using iButton sensors and a thermal camera, and the impact on heart rate during the task was analysed. Following each test, participants provided subjective feedback through a questionnaire. The results indicated that reusable gowns boasted a smoother texture, translating to reduced friction on the skin and better heat transfer compared to the disposable fabrics, as indicated using FTT. They also exhibited higher water vapour permeability compared to their disposable counterparts. The wear trials revealed minimal differences in comfort between disposable and reusable gowns. While performing the activity, an increase in body temperature led to decreased RH, yet this rise did not adversely affect subject comfort, as validated using heart rate and questionnaire survey data. From a comfort point of view, switching from disposable to reusable gowns would not have drawbacks, meaning hospitals should be able to switch provided logistics and costs can be managed. [ABSTRACT FROM AUTHOR]

The feasibility of applying the new technology of atmospheric pressure multi-color bath dyeing on woven fabrics was verified from the aspects of yarn selection, fabric organization, color matching, dyeing process, and fabric performance evaluation, etc. According to the expected design requirements, fabric samples were first woven out and dyed, and then the air permeability, color fastness to rubbing and color fastness to soaping of the obtained fabrics were tested. The results show that woven fabrics interwoven with cationic modified polyester and other fibers of different structures can achieve atmospheric pressure multi-color one-bath dyeing, with a high dye uptake rate, and the residual dyeing liquid is clear and reusable. The color fastness to rubbing and color fastness to soap-washing of the fabric are both at grade 4 and above, and the sample cloth has good dyeing fastness. The fabric has good air permeability, and the novel atmospheric pressure cationic dyeable polyester fabric with a triangular cross-section microstructure is more conducive to air circulation than conventional polyester fabrics with a circular cross-section. [ABSTRACT FROM AUTHOR]

This study proposes a process for the preparation of composite laminates using the shear thickening fluid (STF) impregnated aramid fabric and presents some fabric panel configuration strategies. Firstly, this study prepared two kinds of STF using 20 nm and 500 nm silica particles. Then, the STF‐impregnated Kevlar fabrics were laminated and hot‐pressed to form the fabric panels. After that, the ballistic performance of the fabric panels was evaluated by firing the 9 mm steel core projectile using a gas gun. The ballistic tests showed that the ballistic performance of the hybridized configuration panels using STF‐20 treated fabrics as the front panels and STF‐500 treated fabrics as the backing panels was superior, with a reduction of 36.1%–37.6% in the number of perforated layers (4.7–5 layers) compared to a single STF‐treated panel. This study provides a new idea and method for applying STF in protective equipment. Highlights: Shear thickening fluid (STF) and aramid fabric are better combined by hot pressing lamination process;The ballistic properties of fabric panels are significantly improved by hybrid configuration;The ballistic performance enhancement mechanism of composite bulletproof plate was revealed. [ABSTRACT FROM AUTHOR]

In this paper, a new type of core-spun compound aramid yarn has been applied in the construction of UD fabric to investigate if the ballistic performance of the whole fabric could be positively influenced. Three types of fabrics (Fa, Fb and Fc) herein have been developed. Fa is the traditional type of UD fabric with two layers laying at the angle of 0°/90°. Fb is made by adding new CSC aramid yarns inside of Fa at the angle of 0°/90°. Fc is further developed from Fb via changing yarn-ply directions as 45°/-45°, to analyze if the yarn-ply directions would influence on the ballistic performance of new UD fabric. The result is quite positive, as it shows that Fb and Fc have apparent energy absorption capability than Fa, and Fc is the best. This indicates that the introduction of core-spun compound aramid yarns could indeed improve the ballistic performance of UD fabric, and the yarn-ply direction of 45°/-45° is better than that of 0°/90° to absorb more energy. This research has been investigated with the assistance of both the ballistic test and the FEA model. Energy absorption and penetration resistance mechanism are the two major aspects to analyze to reflect the ballistic performance of these fabrics. [ABSTRACT FROM AUTHOR]

It has been reported that the ply gap influences the ballistic resistance of spaced multi-ply fabric systems, but its working mechanism was not well-understood. This paper reports the experimental and numerical approaches and results of an investigation on the mechanisms that enable the improved ballistic performance of spaced multi-ply systems. Penetration tests were performed over a range of impact velocities ranging from 200 m/s to 400 m/s. The results confirmed that the ply gap is beneficial to the energy absorption capability of the systems. This is because the front plies tend to absorb more energy when they are not immediately constrained by the rear plies. During a ballistic event, the gap relieves the reflection of the compressive pulse, prolonging the projectile engagement time with the front plies; on the other hand, the rear plies become increasingly less active in dissipating energy as the gap increases. When the gap is sufficiently widened to avoid any interference between the plies before the failure of the front ply, the responses of the whole system no longer vary. It was also found that the ballistic performance of the spaced systems is influenced by ply thickness, impact velocity, and the stacking order of the ply gap. [ABSTRACT FROM AUTHOR]

Copyright of Estudios Gerenciales is the property of Universidad ICESI and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to improve the impact resistance of bulletproof materials, the warp-knitted axial fabric formed by the warp-knitted inlay yarn and the full-width inlay yarn is analyzed and three-dimensional simulation is carried out. The weaving principle and structural characteristics of warp-knitted axial fabrics for bulletproof are studied by establishing a general digital mathematical model of padding yarn, a mathematical model of threading yarn and a basic model of coil. According to the established digital mathematical model of padding yarn, the position of dodging padding yarn in this kind of warp-knitted axial fabrics for bulletproof is judged, so as to assign the position of dodging padding yarn, and then the force analysis of the weft insertion guide bar is carried out to obtain the offset consistent with the object. The research results show that JavaScript and C# are used as computer programming languages to realize the simulation of this kind of bulletproof warp-knitted axial fabric, which provides a quick and effective method for the structure exploration and mechanical analysis of bulletproof warp-knitted axial fabric. [ABSTRACT FROM AUTHOR]

This research investigated the ballistic response of homogenous and hybrid multi-ply fabrics toward developing a full-scale hybridized soft armor system. Fabrics with varying yarn and thread counts were manufactured from para-aramid and ultra-high molecular weight polyethylene yarns through a plain-woven architecture. Homogeneous fabrics used the same yarn and thread count for two- and three-ply systems. For hybrid systems, two- and three-ply stacks were assembled in various sequences including increasing and decreasing cover factor (Cfab) and varying yarn types as the strike face and rear face. Ballistic impact testing was performed on all fabrics at low (340 m s−1) and high velocity (620 m s−1). Observations and measurements were performed to determine failure mechanisms, energy absorption, transverse wave propagation, and system effects of multi-ply systems. Hybrid systems showed significant differences in specific energy absorbed (SEA), dependent on the layer order. The para-aramid hybrid systems impacted at 340 m·s−1 showed a significantly greater SEA when the fabrics were ordered with an increasing rather than a decreasing cover factor. At 620 m·s−1 the difference in SEA was less pronounced or absent entirely. It was concluded that hybridization would enhance the performance of a soft armor system and was likely to be most effective for the rear layers of the system where fabrics with a progressively increasing cover factor that were manufactured of fine (550 dTex) para-aramid yarns would offer an advantage. The front layers of the system, subjected to higher strain loading, would benefit from low cover factor fabrics (0.76), which maximize the dissipation of strain from the point of impact. [ABSTRACT FROM AUTHOR]

To explore the decay performance of flexible sensors and promote the application of flexible sensors in daily life, PEDOT: PSS/PET flexible fabric sensors were prepared by impregnation coating process with PEDOT: PSS as conductive filler. The effects of thermal oxidation, water washing, acid, and ultraviolet light treatment on the flexible sensors were studied, and the structure and performance of the sensors were characterized. The results show that PEDOT: PSS/PET flexible fabric sensor has a wide sensing range (0% ~ 70%) and good cycle stability (> 1 000 cycles). The resistance signal measured by fitting the sensor to different parts of the human body shows that the prepared sensor has good performance in real-time monitoring of human joint movement. However, under the influence of external factors such as water washing, acid, heat, and ultraviolet, the prepared flexible sensor has been damaged to varying degrees, and its stability declines or even there is no sensing response. [ABSTRACT FROM AUTHOR]

Medical textiles, including surgical gowns, masks are used as obstacles to prevent the risk of infection for both doctor and patient. The widespread of bacteria and viruses, e.g. chronic hepatitis B, hepatitis C and currently Covid-19 viruses in the patient population is very common. In this work, multifunctional eco-friendly polyester fabrics have been produced by in situ impregnation of 2-((E)-(2-(2,4-dinitrophenyl)hydrazono)methyl)-4-((E)-phenyldiazenyl)phenol disperse dye onto magnetic iron oxide nanoparticles. The technique endowed polyester fabrics with a new color as well as magnetic and antibacterial functionalities. The colored magnetic nanoparticles showed high affinity toward fabrics. Besides, the unbound dye could be easily collected from wastewater by a magnet, significantly facilitate the wastewater treatment. The treated fabrics were analyzed by energy dispersive X-ray spectroscopy, scanning electron microscopy, X-ray diffraction and vibrating sample magnetometry. Colorimetric values, tensile properties and fastness of the composite fabrics were also measured. The tensile properties of the composite were increased after functionalization. The wettability features of the fabric were investigated and showed a significant improvement. Also, the toxicity of the resulted fabric was exhibited low toxicity against wi-38 cell line. These results indicate the potentiality of the suggested technique in producing multifunctional fabrics with various applications, especially as medical textiles. [ABSTRACT FROM AUTHOR]

The importance of inter-yarn friction to ballistic fabric has been widely investigated. However, the couple effects of inter-yarn friction, fabric structure and number of layers have not been explored. Therefore, this paper put forward to investigate the ballistic performance of multi-layer fabric panels with different weave structure and inter-yarn friction. Three different structures (plain, sateen and UD-like), various number of layer (1-layer, 4-layer, 8-layer and 12-layer) and three levels of coefficients of friction were considered and their effects on the ballistic performance will be discussed through finite element (FE) method. The impact velocity is set as 475 m/s and the projectile is a 1 g steel flat cylinder with both the diameter and height of 5.5 mm. It has been found that the sateen fabric structure with 12-layer and higher coefficients of friction firstly reduces the projectile velocity to zero, while the corresponding plain structure and the UD-like structure reduce the projectile velocity to 125 m/s and 200 m/s individually, which indicates that when the number of layer and coefficients of friction are both much larger, the sateen fabric shows the best ballistic performance among the three structures. The reasons behind are as following. As far as the structure concerned, sateen structure has more interlacements than UD-like fabric and more straight sections than plain fabric. In addition, at higher coefficients of friction, this structure enables higher stress distribute in more layers and in larger areas than plain fabric and UD-like fabric and give rise to a layer-by-layer fracture but not fracture simultaneously. [ABSTRACT FROM AUTHOR]

This study encompasses the impact of fabric construction, seam angle, and impact force on the behaviour of the parachute canopy. The ripstop and plain-woven fabric stitched at 0° and 45° seam angles have been subjected to the three levels of tensile impact forces derived through a scale-down approach of the C-9 parachute and the behaviour is analysed using a high-speed digital camera. Results indicate that seam angle has a major influence on the performance of the specimen under impact load. The plain-woven samples showed more ability to absorb impact force but higher damage, especially at seam lines of 0° seamed specimen than the ripstop samples. Both the fabric specimens of 0° seam angle induce a form of seam line damage due to the corresponding higher impact force. In contrast, the 45° seam bias angles are quite stable at seam lines and also produce higher work done under varying impact forces. [ABSTRACT FROM AUTHOR]

Estimating the applied power during a stabbing incident, or estimating the minimal force necessary to penetrate the body with a certain weapon is a challenging task in forensic practice. A thorough forensic evaluation of stabbing forces needs objective numerical experimental data. Stabbing tests of 12 different weapons – including knives, a pair of scissors, a fork, screwdrivers, a rasp, a corkscrew, and a utility knife blade – were performed with a Mecmesin MultiTest‐dV material tester on pork loin and ballistic gel to estimate the stabbing forces and dynamics. Penetration force (Fp) and maximal force (Fmax) were recorded, and the registered force curves were analyzed. Fmax was 159.8–212.07 Newton (N), 30.56–30.58 N, 168.9–185.48 N for various knives; 171.39–190.43 N for the pair of scissors, 233.6 N for the fork; 532.65–562.65 N, 370.31–367.19 N and 314.51–432.89 N for various screwdrivers, 44.14–56.62 N for utility knife during pork loin stabbing. The butter knife, corkscrew and rasp were not able to penetrate the pork loin, and the curved fork bent during stabbing. The results prove that weapon characteristics greatly influence the force necessary for penetration. Maximal stabbing force depends mostly on tip sharpness, and the force sharply decreases after penetration occurs, which indicates that edge sharpness is not as important as tip characteristics during stabbing perpendicular to skin surface. The penetration force during stabbing with a pair of scissors is comparable to the penetration force of knives. Stabbing with screwdrivers generally needs larger force than average knives but depends greatly on screwdriver size. [ABSTRACT FROM AUTHOR]

Ballistic clothing is a crucial safety element that helps to save lives of its wearers. According to the protection level, the ballistic vest is reinforced by one or two armor panels designed to resist to attacks destinated to upper parts of the body. The resistance behavior of ballistic body armor depends on several factors. The most important factors are related to the ballistic fabric properties such as the type of fabric, its thickness, its structure, its strength and strain, and the type of the employed resin. In this review paper, the factors influencing the ballistic performances of soft armor panel and hard armor panel are presented. They are investigated based on an in-depth review of previous research studies and experimental test results. This paper also reports the various methods developed by the researchers to improve the performance of ballistic materials. Thus, ballistic material manufactures and researchers could find some guidelines on promising materials and structures that can be used to build efficient body armors. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Textiles & Engineers / Tekstil ve Mühendis is the property of Union of Chambers of Turkish Engineers & Architects, Chamber of Textile Engineers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In previous studies, ballistic impact on the fabric panel was usually simulated at the yarn level, which failed to capture ballistic responses of fibers. This study aims to employ a finite element model based on fiber bundle level to investigate the influence of fabric architecture on ballistic responses. The ballistic performance of fabrics with different architectures was investigated first through ballistic tests. The architecture parameters including aspect ratio of the yarn cross-section and yarn crimp ratio were found to be the dominant factors, which were further investigated through finite element modeling. Finite element results showed that finite element modeling at the fiber bundle level can lead to an increase of frictional energy dissipation during ballistic impact. For the yarn cross-section shape, reduction of the aspect ratio was beneficial on energy absorption due to better fracture synchrony of fibre bundles under impact. The crimp yarn path had a negative effect on stress wave propagation. When yarns were interlaced, the yarn cross-overs in fabric have further hindered the stress wave propagation. In comparison with the low crimp fabric, the fabric with the higher crimp ratio possesses a wider transverse deformation area under impact. Correspondingly, in the high crimp fabric more yarns were involved in the transverse deformation, which resulted in higher energy absorption. However, high stress concentration on the high crimp yarns can result in premature failure of fibers at the impact area. Such results contribute to a further understanding of ballistic responses from different hierarchies of fabric during ballistic impact. [ABSTRACT FROM AUTHOR]

Aiming at the problem of efficient removal of Cr（Ⅵ) in water, this paper adopted the method of surface co-deposition and post-crosslinking, introduced polyethylenimine containing a large number of amino groups onto the surface of polypropylene non-woven fabric, prepared a new kind of efficient Cr（Ⅵ) adsorbent PP-E-PEI,and studied its adsorption performance of Cr（Ⅵ） in water.The results showed that polyethylene-imine successfully reacted on the surface of polypropylene fiber, and the structure was stable in acidic solution.Amino protonation is a necessary condition for Cr（Ⅵ） adsorption.Only when pH≤3.0 can Cr（Ⅵ） be effectively adsorbed.The charge quantity and concentration of coexisting anions are the main factors affecting the adsorption selectivity of Cr（Ⅵ).When co-existing with the univalent anions such as Cl- and NO-3,the selectivity coefficient（K) of the adsorption material for Cr2O72- can reach more than 400.The selectivity coefficient（K） of the adsorbed material for Cr2O72- is between 7 and 54 when it coexists with the bivalent anions such as HPO42- and SO42-.Using polypropylene non-woven fabric as the substrate, the adsorbent is in the form of fiber film, easy to be separated from the solution after the completion of adsorption. [ABSTRACT FROM AUTHOR]

[Display omitted] The outer shell of the bulletproof fabric is one of the important parts that help the shield in performing its function of protection in the best way. In this paper, there are two types of high-performance materials used as the outer shell and finished with knife coating with fluorocarbon and polyurethane coating to improve the performance of the two materials. Five laboratory tests were conducted for both materials to show their functional performance efficiency, the ballistic test was applied using two types of calibers 7.62x54MSC and 7.62x54API. A scanning electron microscope was conducted to show the coating effect on samples. Paired sample T-tests were used to show the differences between variables. An improvement was shown in the performance for both ballistic nylon and Cordura after treatment. Finally cordura is more durable, as it recorded the highest value in Puncture test and less damaged, while ballistic nylon recorded the highest value in the abrasion resistance after the same treatment. [ABSTRACT FROM AUTHOR]

One of the challenges in improving the protective performance of flexible body armor is optimizing woven fabric, so it is critical to understand how different fabrics and fabric arrangements with the same areal density affect their ballistic resistance. An object of this article is to comparatively investigate the ballistic resistance of single-layer and multi-layer woven fabrics with the same areal density. Four single-layer fabrics with areal densities of 70, 125, 200, and 280 g/m² were selected, and multi-layer fabrics (comprising two, three, and four layers) were assembled by folding a single-layer fabric with an areal density of 70 g/m2 . Ballistic impact tests were carried out on the single-layer and multi-layer fabrics to compare their ballistic resistance. The results show that the specific energy absorption of the multi-layer fabric assembly is more than 7% higher than that of the single layer fabric; the multi-layer fabric mainly improves the ballistic resistance by increasing dynamic in-plane force, while the single-layer fabric does so by increasing the maximum transverse deflection. Moreover, from the perspective of fabric application in the flexible body armor, the energy absorption at ballistic limit of the single-layer and multi-layer fabrics was transformed into energy absorption per unit transverse displacement, and the index of the multi-layer fabric is obviously better than that of the single-layer fabric. [ABSTRACT FROM AUTHOR]

The threat posed by buried explosive charges and their explosive dispersal of environmental debris is associated with a variety of debilitating injuries. The dispersion profile of such threats includes particulate in a broad range of particle length scales, which are more destructive to ballistic fabrics than larger particles alone. Smaller particles are initially dispersed at higher speeds, degrading armour fabrics prior to the arrival of the larger penetrating particulate. In the present work, we present a low-cost industrial abrasion test method to investigate the abrasive wear in neat and polymer-coated ballistic fabrics to determine the level of degradation of the fabrics under the abrasive load. These fabrics were subjected to the impingement of an abrasive jet with average particle velocity of 187 ± 20 m/s. The results showed evidence of significant degradation and failure within the ballistic fabrics, that would certainly influence their subsequent ballistic performance. The addition of polymer coatings was able to reduce the abrasive degradation of the fabrics. The failure modes of the polymer composites are similarly described. This methodology shows promise as a means of armour material screening for this particular threat. [ABSTRACT FROM AUTHOR]

In this paper, multi-scale numerical modelling analysis is proposed to study the ballistic responses of a Kevlar KM2 woven fabric. Three meso-microscopic multi-scale numerical models are conducted by varying the number of microscopic primary yarns in the impact zone from 2 to 10. In each model, we analyse the evolution of the contact force, the projectile velocity and the fabric energies. An analysis of the failure modes of each configuration is also performed. Results of the three multi-scale models and a mesoscopic model are compared in order to find the optimal number of microscopic primary yarns to predict the fabric's ballistic behaviour. It is highlighted that the multi-scale model consumes a reasonable computation cost. Furthermore, with the primary yarns modelled in the fibre scale, this model can fully describe the complex physical phenomena, such as fibre failure and the interaction between fibres, fibres and yarns, that occur during the impact. [ABSTRACT FROM AUTHOR]

In this paper, multi-scale numerical modelling analysis is proposed to study the ballistic responses of a Kevlar KM2 woven fabric. Three meso-microscopic multi-scale numerical models are conducted by varying the number of microscopic primary yarns in the impact zone from 2 to 10. In each model, we analyse the evolution of the contact force, the projectile velocity and the fabric energies. An analysis of the failure modes of each configuration is also performed. Results of the three multi-scale models and a mesoscopic model are compared in order to find the optimal number of microscopic primary yarns to predict the fabric's ballistic behaviour. It is highlighted that the multi-scale model consumes a reasonable computation cost. Furthermore, with the primary yarns modelled in the fibre scale, this model can fully describe the complex physical phenomena, such as fibre failure and the interaction between fibres, fibres and yarns, that occur during the impact. [ABSTRACT FROM AUTHOR]

This study aims to investigate the energy absorption of seam areas in sportswear. Weft knitted fabrics with two structures of plain and rib were fabricated by polyester/Lycra and viscose/ Lycra yarns. Fabrics were stitched in two stitch classes. Moreover, two types of seams were considered. A pull-out test was carried out on all samples to determine the energy absorption values. Furthermore, a finite element model was applied to predict the energy absorption of each structure. The unit cell of each sample was created in ABAQUS software and the tensile load was applied to the stitch yarn. The unit cells of the fabric and the stitched section were modeled in the meso-scale and then elastic and viscoelastic properties of the yarns were assigned to the model. The energy absorption of the sample with rib pattern, lapped seam, and 607 stitch class was more than other samples. Also, the numerical and experimental results showed a high correlation with each other in samples with 304 stitch class and flat seam type. [ABSTRACT FROM AUTHOR]

The importance of inter-yarn friction to ballistic fabric has been widely investigated. However, the couple effects of inter-yarn friction, fabric structure and number of layers have not been explored. Therefore, this paper put forward to investigate the ballistic performance of multi-layer fabric panels with different weave structure and inter-yarn friction. Three different structures (plain, sateen and UD-like), various number of layer (1-layer, 4-layer, 8-layer and 12-layer) and three levels of coefficients of friction were considered and their effects on the ballistic performance will be discussed through finite element (FE) method. The impact velocity is set as 475 m/s and the projectile is a 1 g steel flat cylinder with both the diameter and height of 5.5 mm. It has been found that the sateen fabric structure with 12-layer and higher coefficients of friction firstly reduces the projectile velocity to zero, while the corresponding plain structure and the UD-like structure reduce the projectile velocity to 125 m/s and 200 m/s individually, which indicates that when the number of layer and coefficients of friction are both much larger, the sateen fabric shows the best ballistic performance among the three structures. The reasons behind are as following. As far as the structure concerned, sateen structure has more interlacements than UD-like fabric and more straight sections than plain fabric. In addition, at higher coefficients of friction, this structure enables higher stress distribute in more layers and in larger areas than plain fabric and UD-like fabric and give rise to a layer-by-layer fracture but not fracture simultaneously. [ABSTRACT FROM AUTHOR]

This study is devoted to reveal the influence of weaving architectures and impact locations on the ballistic resistance of UHMWPE (ultrahigh high molecular weight polyethylene) fabrics. Firstly, a mesoscopic model of UHMWPE fabric is established and the accuracy of the numerical method is verified. Subsequently, the models with different weaving architectures are further established, and the impact resistance performances are evaluated. Finally, the influence factors on the fabric ballistic resistance is explored. It is proved that the ballistic resistance of UHMWPE fabric mainly dominated by the tensile strength of yarn under high-velocity impact. The plain fabric shows best anti-ballistic performance, while basket and woven fabric are slightly inferior. The damage pattern of fabrics with different weaving architectures changes greatly. In addition, this study proposes a residual impact velocity correction model for projectile based on the probability distribution of impact positions, which can better characterize the protective ability of fiber fabrics. [ABSTRACT FROM AUTHOR]

Aramid fabrics are widely used in bulletproof armor because of their excellent mechanical properties. Previous studies have shown that ultraviolet radiation has a negative effect on the mechanical properties of aramid yarn, so improving the mechanical properties and impact resistance of aramid fabrics under ultraviolet radiation has become a research focus. In this work, aramid fabric was modified with CuO and ZnO particles to improve its ballistic performance under ultraviolet radiation. The ballistic impact resistance response and microscopic failure mechanisms of aramid fabrics under ultraviolet radiation were analyzed in detail. Under ultraviolet radiation, the ballistic limit velocity (v bl) of the CuO/ZnO-modified aramid fabric was 185.1 % greater than that of a neat fabric with a similar areal density. The v bl of the single-layer modified fabric was 45.6 % greater than that of the two-layer neat fabrics. The decrease in the ballistic performance of the aramid fabric under ultraviolet radiation was attributed to surface damage caused by the fracture of the chemical structure of the fibers, which weakened the mechanical properties of the fabric. The numerical simulation results were highly consistent with the ballistic impact test results, and the error between the numerical simulation and experimental results was within 10 %. The effects of changes in the mechanical parameters of the fabrics on the protection mechanism and energy absorption structure during ballistic impact were investigated. The energy dissipation of the modified fabric was at least 147.7 % greater than that of the neat fabric, further explaining the significant improvement in the ballistic performance of CuO/ZnO-modified fabrics under ultraviolet radiation. • The effects of ultraviolet radiation on the ballistic properties of aramid fabrics were analyzed. • The macro and micro ballistic degradation mechanisms of aramid fabrics were highlighted. • A new and efficient modification method for improving ballistic performance of aramid fabric under ultraviolet radiation was introduced. • The energy absorption structure of fabrics under ultraviolet radiation were described. • Author statement. [ABSTRACT FROM AUTHOR]

The focus on advancing armor systems, combining enhanced ballistic resistance properties with reduced weight, has gained considerable attention as nations recognize the need to fortify sophisticated self-defense mechanisms against prospective military confrontations and threats. The evolving landscape of protective body armor necessitates innovative materials that combine flexibility with high-strength performance. This review article delves into the advancements and potential of carbon nanotubes (CNTs) based soft body armor materials, assessing their structural, mechanical, and protective properties. Beginning with an overview of the unique characteristics of CNTs that make them promising candidates for soft armor applications, the paper scrutinizes the incorporation of CNTs via different techniques to prepare composites for ballistic protection. These methods includes dispersion of CNTs within polymer matrix to impregnate ballistic fabrics, interleaving of CNTs macroform in between the layers of fibers, growth of CNTs over the surface of fabrics, and CNTs based fabrics. Additionally, the review highlights recent experimental studies and computational models, providing insight into the initial and residual velocity, absorbed energy, ballistic limit, and back face deformation characteristics of armor materials incorporating CNTs. Moreover, a comprehensive analysis of the challenges, such as scalability, cost-effectiveness, and environmental concerns associated with CNTs integration, is presented. By consolidating insights from diverse research endeavors, this review aims to offer a comprehensive insight into CNTs-based soft body armors, elucidating their potential to redefine the future of protective materials for both defense and civilian applications. [Display omitted] • Inter yarn friction is crucial to improve impact resistance of soft body armors. • Introducing various techniques for incorporating CNTs in soft body armors • Improvement in impact performance of body armors on incorporating CNTs [ABSTRACT FROM AUTHOR]

This study aims to identify the influence of resin permeation on ballistic responses of fabric laminates. According to experimental results, when the resin permeation degree was improved, the yarn mobility was greatly constrained due to increasing of the bonding force, and the specific energy absorption of laminates under ballistic impact was degraded in comparison with that of the neat fabric. Different resin permeation states in a single yarn and fabric were simulated through Finite Element (FE) modeling at a fiber-bundle level. For a given resin ratio of 15%, semi-permeation of resin in a single yarn was benefit for energy absorption due to even distribution of impact load at the early impact, but full-permeation of resin resulted in energy absorption degradation due to high stress concentration and premature failure. For laminate models, the yarn mobility was severely constrained not only by resin bonding but also by yarns interlacement. In comparison with the neat fabric, stress distribution area on laminates was decreased 30–70%. Yarns contribution to energy absorption was significantly reduced in particular for principal yarns. Such results indicated that perfect resin permeation in armor-grade composite played a negative effect on ballistic energy dissipation due to low material utilization efficiency. [ABSTRACT FROM AUTHOR]

As a ubiquitous paradigm of instabilities and mixing that occur in instances as diverse as supernovae, plasma fusion, oil recovery, and nanofabrication, the Rayleigh–Taylor (RT) problem is rightly regarded as important. The acceleration of the fluid medium in these instances often depends on time and space, whereas most past studies assume it to be constant or impulsive. Here, we analyze the symmetries of RT mixing for variable accelerations and obtain the scaling of correlations and spectra for classes of self-similar dynamics. RT mixing is shown to retain the memory of deterministic conditions for all accelerations, with the dynamics ranging from superballistic to subdiffusive. These results contribute to our understanding and control of the RT phenomena and reveal specific conditions under which Kolmogorov turbulence might be realized in RT mixing. [ABSTRACT FROM AUTHOR]

This paper discusses the novel multimaterial arbitrary-Lagrange-Euler (MM-ALE) based approach for modeling shear-thickening fluid (STF)–treated fabric under ballistic impact. The friction-based model of fabric implements the effect of interyarn friction on the ballistic performance of the neat and STF-treated fabric. Furthermore, this paper presents the limitations of friction-based modeling of STF-treated fabric under a wide range of projectile velocities. Such a limitation is the exact prediction of interyarn coefficients of friction for STF-treated fabric for the complex phenomenon of ballistic impact. The results obtained from the friction-based model for the ranges of interyarn coefficients and fabric sett showed that there is an enhancement in the ballistic performance due to an increase in the coefficient of friction up to a critical value of friction coefficients. It was observed that beyond the critical level, there was no improvement in the ballistic performance of the fabric. However, there was a decrease in the ballistic performance beyond the critical friction level. Moreover, the numerical model of neat fabric using friction-based models as validated and implemented in the development of MM-ALE-based modeling of STF-treated fabric. The novel MM-ALE-based modeling approach will enrich the understanding of the STF mechanism under ballistic impact for STF-treated fabric systems. The limitations of friction-based models shall be handled using the MM-ALE based technique. [ABSTRACT FROM AUTHOR]

As destructive power of firearms raises over the years, ballistic armors are in continuous need of enhancement. For soft armors, this improvement is invariably related to the increase of stacked layers of high-strength fiber fabrics, which potentially restrains wearer mobility. A different solution was created in the early 2000s, when a research work proposed a new treatment of the ballistic panels with non-Newtonian colloidal shear thickening fluid (STF), in view of weight decreasing with strength reinforcement and cost-effective production. Since then, databases reveal a surge in publications generally pointing to acceptable features under ballistic impact by exploring different conditions of the materials adopted. As a result, several works have not been covered in recent reviews for a wider discussion of their methodologies and results, which could be a barrier to a deeper understanding of the behavior of STF-impregnated fabrics. Therefore, the present work aims to overview the unexplored state-of-art on the effectiveness of STF addition to high-strength fabrics for ballistic applications to compile achievements regarding the ballistic strength of this novel material through different parameters. From the screened papers, SiO 2 , Polyethylene glycol (PEG) 200 and 400, and Aramid are extensively being incorporated into the STF/Fabric composites. Besides, parameters such as initial and residual velocity, energy absorbed, ballistic limit, and back face signature are common metrics for a comprehensive analysis of the ballistic performance of the material. The overview also points to a promising application of natural fiber fabrics and auxetic fabrics with STF fluids, as well as the demand for the adoption of new materials and more homogeneous ballistic test parameters. Finally, the work emphasizes that the ballistic application for STF-impregnated fabric based on NIJ standards is feasible for several conditions. [ABSTRACT FROM AUTHOR]

The aims of our investigation are to increasing inter-yarn friction by using polyurethane resin for superior ballistic protection without affecting the weight. In our concentration, we have used three different resin impregnated (25 × 25 cm) (Type-A), (4.5 × 4.5 cm) (Type-B), (9 × 9 cm) (Type-C) structure to treat our Kevlar fabrics and 12% wt. PU solution as resin. Grounded on our three different resin-impregnated fabric, we have been evaluated the weight increase percentage to analyze our core objectives maintaining the less weight escalation ratio with better ballistic performance. As the resin impregnation amount increases, the yarn or fiber dimensions lead to fabric stiffness. Later on, the yarn pull-out installation was created and the yarn (single and multiple) pullout tests were performed on both plain and resin impregnated structures to find the differentiation. The result of the investigation shows high-density resin-impregnated fabric indicates a higher pull-out force contrasted with those of low-resin impregnated fabric structure. Fabric displacement at max. Force during multiple-end pull-out indicated a higher fabric displacement (mm) rate contrasted with that of the single pull-out. Optical microscopic examination is done to observe the progressions on pulled out regions. During our observation, no implication variety was found in the surface at a specified loading rate except adjacent yarn displacement grounded on the amount of yarn pulled out. Utilization of resin impregnation builds the commitment of more yarns as the slippage of yarns is limited thus leads to the higher energy required rate. Finally, by ballistic perforated impact parameters, it is affirmed that expanding inter-yarn friction can improve ballistic performance of fabrics. Ultimately, it is concluded in the way that these new ballistic resin-impregnated structures come up with higher inter yarn friction, low expense, less weight, considerable stiffness of the fabric and the reliable ballistic performance on the finished result. [ABSTRACT FROM AUTHOR]

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3D woven fabric has great application potential in military armor systems. Here we report numerical simulation of 3 D angle interlock woven fabric(3DAWF) subjected to the ballistic impact using LS-DYNA. We employed membrane elements to construct the mesoscale yarn-level 3DAWF model to improve computational efficiencies and accuracy. The simplified Johnson-Cook (SJC) material model was proposed for simulating yarns' dynamic behaviors under high-speed impact loadings. The SJC material model and commonly used strain-rate dependent material model Cowper-Symonds (CS) were taken into the FEA model to simulate the fabric's ballistic impact behaviors separately. The ballistic impact tests of 3DAWF subjected to the Full Metal Jacket (FMJ) projectile under the strike velocity 190 ∼ 320 m/s were carried out to validate the new material model. Comparing the results between the tests and theoretical model found that the FEA model using the SJC material model can accurately predict projectile's residual velocities and fabric's deformation and damages. The numerical model using SJC yarn constitutive models can precisely capture the impact mechanism of 3DAWF. [ABSTRACT FROM AUTHOR]

Textile ballistic shields are the basis of protection against bullets and fragments with low kinetic energy. They are usually made of para-aramid fabrics or unidirectional structure (UD) sheets of ultra-high molecular weight polyethylene (UHMWPE). The aim of the research presented in the article was to obtain ballistic packages made of embroidered structures and to compare their ballistic properties with those of woven structures in terms of deformation of the standardized ballistic substrate after impact with a 9 mm bullet at a velocity of 380 ± 3 m/s. Using the tailored fiber placement method, embroidered structures were fabricated by embroidering two sets of para-aramid threads at an angle of 90°. As the woven structures, the use of para-aramid fabric made of the same yarn and with a surface weight comparable to that of embroidered structures was adopted. Ballistic packages consisted of 26 layers in five variants, also taking into account the hybrid arrangement of woven and embroidered layers. Ballistic tests have shown that the best ballistic properties have hybrid packages made by folding 13 woven and then 13 embroidered layers, where the maximum deformation of the plasticine substrate is below 23 mm. The conducted research confirmed that embroidered structures in appropriate combination with woven structures can significantly improve the ballistic properties of textile packages. [ABSTRACT FROM AUTHOR]

This study compared error rates during the personal protective equipment (PPE) removal process under different base-layer cooling conditions while performing the doffing procedures. Ten participants were recruited and received training on the standard doffing procedures before participating in the experiments. The participants were randomly assigned to one of the three base-layer conditions and ran on a treadmill for 30 min. Their physiological biometrics were monitored during exercise trials, and error rates were calculated. The results revealed a significant difference in error rates when PPE was worn over base-layer scrubs made of a cooling fabric versus when it was worn over the conventional medical scrubs. Further, there was a strong negative relationship between the body coverage amount with the cooling fabric and error rates occurring during the doffing procedures. Findings suggested practical considerations for the operational monitoring system and improved PPE design to avoid unintentional errors during the doffing procedures. [ABSTRACT FROM AUTHOR]

• Both experimental and modeling techniques to characterize the ballistic performance of woven fabrics are comprehensively introduced. • The underlying mechanisms of energy absorption and influencing factors are presented from a full-scale discussion. • The recommendations for the future design and research work of flexible armor systems are proposed. With the advancement of firearms and explosive weapons on the battlefield or during law enforcement, the requirements of flexible protective systems have been made more challenging, primarily in that the protective armor should provide better protection with reduced weight and limited restriction on mobility. Confronted by such a challenge, engineering design of ballistic fabrics and panels becomes a reasonable approach to provide better protection using fibers and structures that are currently available for this application. The currently most used commercially available high-performance fibers are aramid and Ultra-high-molecular-weight polyethylene (UHMWPE). Most ballistic fabrics are manufactured by weaving and cross-plying, though knitting, braiding, and nonwoven techniques catch up or even move ahead very fast. In this paper, a comprehensive review of the ballistic impact of woven fabric is presented. The first section of this paper introduces the background of this topic and the relevant previous review papers summarizing the numerous publications in this field. This is followed by the presentation of the experimental techniques used to characterize the performance and responses of woven fabrics. Apart from experimental work, a summarization of the modeling techniques, such as early semi-empirical, analytical, and most recent numerical models are considered. In addition, the underlying mechanisms of energy absorption and their corresponding influencing factor that bias the responses is discussed. Based on the influencing factors, approaches to further improve the penetration resistance of woven fabrics is highlighted in the final section. [ABSTRACT FROM AUTHOR]