Dynamic Puncture Research Articles

Being thin-skinned can still reduce damage from dynamic puncture.

The integumentary system in animals serves as an important line of defence against physiological and mechanical external forces. Over time, integuments have evolved layered structures (scales, cuticle and skin) with high toughness and strength to resist damage and prevent wound expansion. While previous studies have examined their defensive performance under low-rate conditions, the failure response and damage resistance of these thin layers under dynamic biological puncture remain underexplored. Here, we utilize a novel experimental framework to investigate the mechanics of dynamic puncture in both bilayer structures of synthetic tissue-mimicking composite materials and natural skin tissues. Our findings reveal the remarkable efficiency of a thin outer skin layer in reducing the overall extent of dynamic puncture damage. This enhanced damage resistance is governed by interlayer properties through puncture energetics and diminishes in strength at higher puncture rates due to rate-dependent effects in silicone tissue simulants. In addition, natural skin tissues exhibit unique material properties and failure behaviours, leading to superior damage reduction capability compared with synthetic counterparts. These findings contribute to a deeper understanding of the inherent biomechanical complexity of biological puncture systems with layered composite material structures. They lay the groundwork for future comparative studies and bio-inspired applications.

Quasi-static and dynamic stab behavior and damage mechanisms of the spiral/laminated structure of CFRP

Stab resistance depends on the material’s strength and stiffness. Puncture energy is absorbed mainly through fracture and friction in the damaged area. To reduce stress concentrations and diffuse impact energy, this paper proposes a spiral CFRP inspired by spiral grass. Comparison of the puncture resistance of spiral CFRP and laminated CFRP by quasi-static and dynamic puncture. After separating the puncture process into longitudinal piercing and transverse cutting, it was found that spiral CFRP had excellent cutting resistance, with a maximum cutting force 44% higher than laminated CFRP. However, the detachment of the central structure leads to weaker perforation resistance of spiral CFRP than laminated CFRP. Laminated CFRP was found to undergo internal delamination damage after perforation by microscopic characterization and finite element analysis. Spiral CFRP has a helical yarn path and the interface distribution parallel to the impact direction, resulting in a greater susceptibility to delamination damage and rapid spiral crack propagation. The damaged area of spiral CFRP is up to 416% larger than that of laminated CFRP. The structural instability also resulted in a higher penetration depth for spiral CFRP than for laminated CFRP. The composite structure provides better puncture resistance than a single structure. Due to the combined advantages of the passivation of spiral CFRP and the structural stability of laminated CFRP, Sprial/laminated CFRP has the highest puncture resistance, with a maximum puncture load of 1,467 N, and is not penetrated at a puncture energy of 24 J. The spiral structure incorporating crack-inducing and transverse damage resistance could offer a promising approach to developing stab-resistant materials.

Stab resistance mechanism of lightweight PLA/CFRP hybrid composite structures

The preparation of lightweight and high-performance material is of great significance for developing stab-resistant clothing. This paper proposes a stab-resistant composite structure combining lightweight polylactic acid (PLA) and carbon fiber reinforced polymer (CFRP). The effect of stacking sequence and filling density on the puncture resistance of composite structures was investigated by dynamic puncture and quasi-static puncture. Puncture load, energy and depth are studied as key parameters of puncture resistance. This paper investigated composite structures' failure process and damage morphology using high-speed camera photography and microscopic imaging techniques. The results show that the composite structure exhibits the strongest puncture resistance when CFRP is designed on the top layer of PLA. The higher the filling density, the lower the puncture depth of the composite structure, but the increase in the overall weight eventually leads to a decrease in the puncture specific energy (PSE). The introduction of the bottom PLA delays the penetration point of the composite structure and increases the absorption of the penetration energy by the CFRP before penetration. The final damage modes of composite structures include fiber fracture, slip and pull-out, matrix fracture and peel damage, as well as fracture damage and plastic deformation of PLA materials.

Investigation of the rate-mediated form-function relationship in biological puncture

Puncture is a vital mechanism for survival in a wide range of organisms across phyla, serving biological functions such as prey capture, defense, and reproduction. Understanding how the shape of the puncture tool affects its functional performance is crucial to uncovering the mechanics underlying the diversity and evolution of puncture-based systems. However, such form-function relationships are often complicated by the dynamic nature of living systems. Puncture systems in particular operate over a wide range of speeds to penetrate biological tissues. Current studies on puncture biomechanics lack systematic characterization of the complex, rate-mediated, interaction between tool and material across this dynamic range. To fill this knowledge gap, we establish a highly controlled experimental framework for dynamic puncture to investigate the relationship between the puncture performance (characterized by the depth of puncture) and the tool sharpness (characterized by the cusp angle) across a wide range of bio-relevant puncture speeds (from quasi-static to sim 50 m/s). Our results show that the sensitivity of puncture performance to variations in tool sharpness reduces at higher puncture speeds. This trend is likely due to rate-based viscoelastic and inertial effects arising from how materials respond to dynamic loads. The rate-dependent form-function relationship has important biological implications: While passive/low-speed puncture organisms likely rely heavily on sharp puncture tools to successfully penetrate and maintain functionalities, higher-speed puncture systems may allow for greater variability in puncture tool shape due to the relatively geometric-insensitive puncture performance, allowing for higher adaptability during the evolutionary process to other mechanical factors.

Optimizing the Anti-stab Performance of Fiber Composites by Using Ceramic Particle Reinforcements

Fiber reinforced composite is widely used in current stab-proof equipment, the high performance and light weight have always been pursued for a long time. The present study optimizes the anti-stab performance of fiber composites by using silica and silicon carbide ceramic particle reinforcements. The anti-stab performance of different composite processes and composite structures were characterized. Silica particle reinforcements were added to the fiber fabric in the form of a shear thickening fluid (STF). Quasi-static puncture tests results revealed that the puncture force of the fiber composite prepared by STF dilution process was significantly higher than that of the sample prepared without dilution. Under the same areal density, the puncture force of the sample with a dilution ratio of 1:2 had been improved by 79.9% higher than that of pure fiber fabrics. Silicon carbide particle reinforcements were added to the fiber fabric in the form of particles/epoxy resin coating. After coated with SiC particles, the aramid fiber fabric not only greatly improves the puncture force, but also significantly increases the wear of the tool. The dynamic puncture test results further showed that the SiC coated / STF aramid plain weave fabrics exhibited excellent stab-resistant performance.

Thermoplastic Laminated Composites Applied to Impact Resistant Protective Gear: Structural Design and Development

Laminated composites have been commonly applied to all fields. When made into laminated composites, Kevlar woven fabrics are able to provide the required functions. In this study, two types of TPU are incorporated to improve the intralayer features of Kevlar/TPU laminated composites. Hence, the Kevlar/TPU laminated composites consist of firmly bonded laminates while retaining flexibility of the fabrics. Being the interlayer of the laminated composites, the TPU layer provides adhesion while strengthening the tensile property, dynamic puncture resistance, and buffer strength of Kevlar/TPU laminated composites. The test results indicate that with a blending ratio of two types of TRU being 85/15 wt%, the Kevlar/TPU laminated composites exhibit a tensile strength of 18.08 MPa. When the stacking thickness is 1 mm, the tensile strength is improved to 357.73 N with the buffering strength reaching 4224.40 N. Notably, with a thickness being 1.2 mm, the laminated composites demonstrate a dynamic resistance being 672.15 N. In the meanwhile, functional Kevlar fabrics are allowed to keep the fiber morphology owing to the protection of TPU composite films. Considering the composition of protective gear, Kevlar/TPU laminated composites possess a powerful potential and are worthwhile exploring.

Puncture resistance of STF impregnated MWCNTs-grafted carbon fabrics

In this study, STF with the silica concentration of 20 wt% was fabricated. Functionalized multi-walled carbon nanotubes (MWCNTs) were chemically bonded onto the carbon fibers by using grafting technique. In grafting technique, DMF/PAN fiber/MWCNTs suspension sprayed onto each surface of carbon fabric and MWCNTs were grafted by a thermal treatment at 250 °C. Neat and MWCNTs-Grafted carbon fabrics were impregnated with STF with the silica loading of 20 wt%. Then, dynamic and quasi-static puncture resistance of neat, STF impregnated, MWCNTs-Grafted and MWCNTs-Grafted-STF impregnated carbon fabrics were examined. STF impregnation was detected to lead to a decrease in dynamic puncture resistance and an increase in quasi-static puncture resistance. Dynamic puncture resistance of MWCNTs-Grafted carbon fabric was found to be less than neat fabrics due to larger gaps between yarns occurred after thermal stabilization. Also, due to the greater gap between yarns, complete perforation occurred at lower penetration depth in MWCNTs-Grafted carbon fabrics than neat carbon fabrics in quasi-static puncture tests.

Dynamic puncture behavior of the calendered geotextile compound fabrics: optimization using the Taguchi design of experiment

For improving dynamic puncture resistance (cone drop test) of the needle-punched nonwoven geotextile fabrics, employing a calendered compound tri-layer sandwich-structure of nonwoven/woven/nonwoven was aimed by reinforcement of the nonwoven fabric with incorporating a high strength low extensible woven fabric. For this purpose, five main variables including woven fabric structural characteristics, compound punch density and fundamental adjustments of the calendering treatment, individually in three levels were statistically investigated using Taguchi design of experiment. In addition to conventional measuring diameter of the hole created by the dropping cone, a high-speed video processing technique was also used to calculate the expansion energy of the formed hole using MATLAB-designed software. A comprehensive review of the results showed while the studied reinforcement leads to an increase in the puncture resistance, the calendering parameters have the highest effect on the hole diameter and the expansion energy is also more affected by the woven fabric variables.

Dynamic puncture modeling of polyester needle-punched nonwoven geotextile fabrics using finite element method

Investigating the properties of the needle-punched nonwoven geotextile fabrics in order to improve their performance is important, not only from economical aspects, but also for their multipurpose applications. One of these properties is their resistance to puncture, especially in the dynamic state. Experimental study of this behavior requires the use of special equipment, time, cost, etc. which can be also affected by the unpredictable errors. Therefore, in this study, a finite element based model for prediction of the cone drop dynamic puncture behavior of needle-punched nonwoven geotextile fabrics has been proposed. In order to compare the results of the model with the real situation, a number of four samples with different specifications, including basis weight, thickness, needle penetration depth and punch density were prepared and tested according to EN ISO13433:2006 method. The root mean square error of the cone velocity results as well as the diameter of the hole created indicates a significant agreement between the experimental and the model results. Moreover, the obtained results are confirmed by a validation sample. The proposed model can also be used to estimate the velocity change of the cone, the momentary forces exerted by the fabric to the cone, the stress distribution on the geotextile fabric and to forecast how the puncture happens and the created hole expands during the puncture.

Synergistic Effects of Needle Punching and Shear-Thickening Fluid on Sandwich-Structured Composites Made of Nonwoven and Woven Fabrics

This study explores the influences of needle punching and a shear-thickening fluid (STF) on the stab resistance sandwich-structured composites made of nylon nonwoven and aramid fabrics. Needle punching and different treatments of aramid fabric are conducted to obtain the composites. The effects of needle punching and different treatments of aramid fabrics on the sandwich-structured composites were examined using quasi-static puncture resistance, quasi-static stab resistance, dynamic puncture resistance, and bursting property tests. Results show that needle punching and incorporation of STF positively influence the stab resistance of the composites. This study provides an innovative method to reduce the number of lamination layers and decrease the weight.

Fabric Composites Reinforced with Thermally Bonded and Irregularly Aligned Filaments: Preparation and Puncture Resistant Performance.

This study proposes fabric composites with improved static and dynamic puncture via increasing a friction force to restrain the slide of filaments as well as the compression and abrasion between the fibers and the puncture probe. The the bi-layered shell layers of composite fabrics are composed of aramid staple fibers and nylon staple fibers and a layer of low-melting-point polyester (LPET). The nonwoven layer consisting of recycled aramid and nylon staple fibers provides a shear effect to dissipate part of the puncture energy. Reinforcing interlayers include a woven fabric and PET filaments that are circularly aggregated between the surface layers, providing isotropic filament reinforcement and strengthening the resistance against the tip of the puncture probe. The reinforcing filaments may slide after the employment of needle punching, and to compensate for this disadvantage, the LPET layers are used to thermal bond the composite fabrics and the total thickness is controlled at 2 mm. The thermally bonded fabric composites are evaluated in terms of puncture resistance, thereby examining the effects of fabric structure and thermal bonding. According to the test results, the optimal composite structure is the sample N/L/W/F/L/N, which was reinforced by the LPET adhesive layer and irregularly aligned filaments. The sample which used the LPET adhesive layer had a positive influence on static puncture resistance and dynamic puncture resistance, preventing the slide of filaments, but the poor interfacial combination only contributed to limited reinforcement.

Optimizing the processing parameters of mechanical and hydraulic conductivity of geotextile liner

ABSTRACTGlass geotextile reinforcement and needle-punch bonding are applied to compensate for the low mechanical strength of a geotextile clay liner (GCL) and reduce damage under complicated service conditions. Moreover, the effects of glass fibers embedded in the bentonite on hydraulic conductivity are investigated. A hybrid-structure glass geogrid-reinforced GCL (GGCL) is constructed by needle punching the bentonite laminated by a glass geogrid layer and separated by a 0.3 mm thick meltblown nonwoven layer. The central composite design (CCD) is proposed to discuss the effects of needle punch density (ND) and depth of punch (DP) on the tensile properties, quasi-static and dynamic puncture resistances, and hydraulic conductivity of the GGCL, and an empirical regression model of these properties is established. Results show that ND and DP significantly affect tensile the properties and puncture resistances while DP insignificantly affects the hydraulic conductivity of the GGCL. Glass fibers embedded into the bentonite improve the hydraulic conductivity of the material. At the 95% confidence interval, the process parameters can be optimized by the empirical regression model. The proposed regression model is consistent with experimental results and can thus be used to predict the mechanical properties and hydraulic conductivity of GGCL.

Using unwrapped filament tows to strengthen sandwich composites: Puncture and bursting resistance

The combination of appropriate materials and structural design can compensate for flaw of a single pattern, providing the products with better functionalities. In this study, the custom-made nonwoven fabric machine can unwrap the filament tows before needle punching stage. Sandwich composites are proposed, consisting of two nonwoven fabrics as surface layers and laminated loops of filaments as the core. The puncture resistance of the sandwich composites are examined in terms of weight of filament loops and needle-punching depth, examining their influences. The employment of filaments has a remarkable influence on the mechanical performance of the composites. GF4G has static puncture resistance, dynamic puncture resistance, and bursting strength that are 89%, 30%, 88% higher than those of GF1G; 332%, 127%, and 500% higher than those of 2G; and 671%, 400%, and 1260% higher than those of G. Using filaments to reinforce nonwoven fabrics only requires simple equipment and easy operation. Furthermore, based on the requirements of different final products, diverse filaments and multiple parameters can be combined, thereby providing the composites with efficient production, solid reinforcement, and broad applications.

An Investigation into Dynamic Puncture Resistance of the Polyester Needled Nonwoven Geotextiles using Video Processing Technique

Abstract In this study, the dynamic puncture behavior of nonwoven needle-punched polyester geotextiles has been studied using video processing technique. Twenty-seven needle-punched geotextile samples were produced by changing areal weight, needle penetration depth and punch density as independent variables. Cone drop test was carried out on the samples. In addition to measuring the hole diameter (HD), the video processing technique with a high frame rate camera was employed to calculate the energy absorbed by geotextile fabric up to puncture point (Ep) and the hole expansion energy (Ee). Multiple linear regression method was used to develop the predicting relationships between independent and reply variables. The models showed that an increase in areal weight results in an increase in Ep, whereas it causes a decrease in Ee and HD. Moreover, increasing punch density and needle penetration depth, leads to less Ep, and more Ee and HD. In addition, it was also found that significant relationships exist for Ep-HD and Ee-HD.

Mechanical and physical properties of puncture-resistance insole made of Kevlar® recycled selvages

The polyester (PET) fibers and Kevlar® staple fibers, which are recycled from discarded selvages of PET and Kevlar® woven fabrics, are made into nonwoven fabrics using a needle-bonded process. The PET/Kevlar® nonwoven matrices are used as the surface layers, while a glass fiber woven fabric is used as the interlayer. The sandwich-structured composites are saturated with waterborne PU resin and then hot pressed, forming puncture resistant PU-reinforced PET/Kevlar® sandwiches. The sandwiches are evaluated in terms of the tensile property test, the bursting property test, the constant-rate puncture test, the dynamic puncture test, and the drop-weight impact test. The test results indicate that increasing the pick-up rate of PU resin can significantly improve all mechanical properties, suggesting that PU-reinforced PET/Kevlar® sandwiches have protective functions and make good candidate for insoles.

Numerical simulation of dynamic puncture behaviors of woven fabrics based on the Finite Element Method

Research on the simulation and modeling of dynamic puncture penetration is more complex problem due to full consideration of the tightness of the fabric and the sharp profile of the puncture. This study presents numerical simulation of complicated dynamic puncture behaviors on the basis of the roles of extension and stress-wave transmission on the deformation. The unit cell model was used to simulate the yarn crimp and extension during the uniaxial dynamic puncture process. In addition, the puncture deformation and stress distribution of woven fabrics with different elastic modulus and friction distance were simulated followed with dynamic puncture penetration. The result shows that dynamic puncture damage critically depends on the elastic modulus of yarns and the distance between yarns; the inter-yarn distance affects dynamic puncture resistance more significantly. Dynamic puncture stress nonlinearly increases with the elastic modulus, and linearly decreases with yarn distance. The research result indicates that weaving density can be increased to improve dynamic puncture resistance more obviously.

Static and dynamic puncture properties of intra-/inter-laminar reinforced multilayer compound fabrics by needle-punching and thermal bonding

A new approach for intra-/inter-laminar reinforcement using needle-punching and thermal bonding was proposed for improvement of puncture resistance of multilayer compound fabrics that were composed of different kinds of nonwovens and woven fabrics. Effects of woven fabric orientation and thermal bonding on static and dynamic puncture properties were explored. Multilayer compound fabrics with different compositions of nonwoven and sequence of woven fabrics were comparatively discussed to confirm fabric and nonwoven influencing on static and dynamic puncture resistances. Puncture resistance mechanism of plied orientation and thermal bonding was analyzed for multilayer compound fabrics. The research result shows that woven fabric orientation affected static and dynamic puncture resistances more significantly when multilayer compound fabrics were comprised of high-modulus nonwovens and woven fabrics. Plied orientation correlated with the yarn density of woven fabric that was contained in compound fabrics. Contact length between woven fabric and nonwoven, as well as specific fiber toughness from nonwoven, was respectively responsible for static and dynamic puncture resistances of multilayer compound fabrics.

Modeling and optimization of dynamic puncture behaviors for flexible inter-/intra- reinforced compound fabrics

In this article, the new model of dynamic puncture behaviors of intra-/inter- reinforced compound fabrics which are fabricated by nonwovens and reinforced fabrics using needle-punching and thermal bonding technique is constructed by the maximum deformation and stress-wave transmission theory. Moreover, the number of layers for E1 puncture protection is optimized based on numerical analysis of penetration depth. Dynamic puncture model shows that the dynamic puncture resistance depends on elastic modulus of reinforced fabrics, deformation radius and thickness of compound fabrics. The maximum puncture resistance and penetration depth both have parabola relations to number of layers. This study provides the accurate prediction model of puncture force and safety layers for designing puncture-resisting body armor in the future.

Quasi-static and dynamic mechanical responses of hybrid laminated composites based on high-density flexible polyurethane foam

Hybrid laminated composites were fabricated based on high-density flexible polyurethane foam and reinforced with inter/intra-ply hybrid laminates. Transient responses of hybrid composites under quasi-static and dynamic loadings with various thicknesses and expansion factors were comparatively investigated. Experimental results revealed that foam cell collapse and hybrid laminates rupture were dominant mechanisms of energy absorption. Interlaminar stress and composite tensile strength determined the compressive potential energy and double-peak behavior. Quasi-static bursting and puncture resistances exhibited totally different relationships to various constructions and expansion factors. Energy dissipation capacity is influenced more significantly by the constant rate of transverse (CRT) puncture than dynamic puncture process. CRT puncture resistance is superior to the corresponding dynamic puncture resistance for all constructions. The hybrid laminated composites contributes to eliminate more than 95% of the incident force in the drop weight impact test. Compared with non-laminated panel, the hybrid laminated composites exhibited higher resistance to static and dynamic loadings.

Puncture-resisting, sound-absorbing and thermal-insulating properties of polypropylene-selvages reinforced composite nonwovens

In order to realize recycling of polypropylene selvages, polypropylene nonwoven selvages with different plied orientation were inserted between Kevlar/Nylon/low-melting polyester nonwoven fabrics forming composite nonwoven. Low-melting polyester content of nonwoven fabric and hot-pressing temperature of composite nonwoven were both optimized after static and dynamic puncture resistances. Moreover, effects of hot-pressing and plied orientation on static and dynamic puncture resistances, sound absorbing and thermal insulating properties of composite nonwoven were discussed respectively. Result shows that, optimal low-melting polyester fiber content was 30%, and best hot-pressing temperature for composite nonwoven was 180°C. Polypropylene nonwoven selvages improved static puncture resistance, sound absorbing and thermal insulating properties. Hot-pressing slightly increased puncture resistance and obviously improved thermal insulation, but decreased sound absorption coefficient significantly. Plied orientation affected static and dynamic puncture resistance insignificantly, but influenced on sound-absorbing and thermal-insulating properties significantly. When composite nonwoven was plied with 90°/90° polypropylene selvages and hot-pressed at 180°C, the static and dynamic puncture resistances reached 120 N and 80 N, respectively, and thermal conductivity was 0.047 W/mK. Five layers of composite nonwoven before hot-pressing had sound absorption coefficient of above 0.94 at frequency of higher than 1890 Hz.