High-velocity Impact Resistance Research Articles

Experimental study on the high-velocity impact resistance of Vitrimer-based carbon fiber composites

Experimental study on the high-velocity impact resistance of Vitrimer-based carbon fiber composites

Study on transverse high-velocity impact resistance of carbon nanotube films and their based composites

This paper investigates the resistance of Carbon nanotube (CNT) films and their based composites to transverse high-speed impact and explores the effect of resin content on the impact properties. The study utilizes light gas gun experiments and employs numerical simulation to determine the critical penetration velocities for pure CNT films and those films impregnated with 20 %, 50 %, and 80 % epoxy resin solutions. The results demonstrate that including epoxy resin can enhance CNT films' impact-resisting ability, with a noticeable improvement as the resin content increases The observed strengthening mechanism in CNT resin composite films subjected to high-speed impacts primarily is energy absorption. Based on the above results, CNT films were added to the interlayer of composite laminates. It was found that CNTs could help materials resist impact and ensure the integrity of the laminate structure.

An experimental review on enhancing the low and high-velocity impact resistance of NFCs through nanoparticle reinforcement

Nanoparticles are widely used in biocomposite materials due to their ability to improve the mechanical properties of composites. This comprehensive review analyzes the use of nanoparticles to enhance the experimental low and high-velocity impact resistance of natural fiber composites. Various nanoparticles like carbon nanofibers, carbon nanotubes, boron nitride, zinc oxide, and titanium dioxide were investigated as reinforcements at different loading levels. The addition of nano-ZrO2 alone or with graphene oxide yielded the highest impact resistance and interlaminar shear strength of basalt fiber/epoxy composites. Cloisite 20A clay improved the mechanical properties of an epoxy matrix. Carbon/epoxy laminates showed improved maximum impact force, energy absorption, and displacement with 2wt% carbon nanofibers loading. Nanoparticles were found to enhance moisture and temperature resistance by strengthening the fiber–matrix interface. The literature demonstrated that small amounts of well-dispersed nanoparticles can meaningfully improve natural fiber composites’ impact resistance, strength, stiffness, toughness, and energy absorption through mechanisms like crack arresting and bridging. Hybrid carbon-basalt fibers and calcium carbonate nanoparticles also enhanced composite performance. Balancing the nanoparticle loading is crucial to prevent agglomeration effects. Future studies on their toxicity and environmental impacts would be needed for widespread commercial applications of Biocomposites.

Numerical investigation on the high-velocity impact resistance of textile reinforced composite mesh designs inspired by spider web

The need for thin and highly deformable textile reinforcements is constant in sectors like thin composites, catching nets, and complex construction designs (like dome-shape). The conventional rectangular-patterned meshed wovens are used in thin composite structures as reinforcement at the commercial level. These woven textiles are bidirectional and exhibit approximately the same strength along both axes. However, these conventional rectangular-patterned mesh designs show poor impact stress distribution capacity. Interestingly, very thin and fine mesh designs are available in nature. One such example is the spider web structure. These structures have evolved with time and optimised their mesh pattern design for better impact damage resistance and load transfer. In this study, the basalt fibre reinforced mortar textile composites are considered for the investigation due to their growing interest in civil and construction applications. To demonstrate how the mesh geometry in textiles significantly influences the stress transfer, energy absorption, and deformation of reinforcements under various impact situations, three different geometries, (a) square shape mesh, (b) diamond-shaped mesh, and (c) bio-inspired spider web mesh, are modelled and meshed based on the reference geometry’s meshing pattern and dimensions. The results of numerical simulations show that a meshed reinforcement design inspired by spider-orb-web has improved mechanical features compared to conventional square and diamond shape mesh designs under high velocity impact loading.

High-velocity penetration impact characteristics of fiber metal hybrid cylindrical shells: Theoretical and experimental investigation

The high-velocity penetration impact characteristics of fiber metal hybrid (FMH) cylindrical shells are investigated. A finite element (FE) model of such a shell subjected to an internal high-velocity projectile impact is established based on ABAQUS software to predict impact parameters, in which the impact damage failures of FRP, metal, and virtual cohesive layers are considered, respectively. Both literature and experimental results are utilized to verify the current model, with the influences of critical parameters on the residual velocity and specific energy absorption properties being discussed. The outputs provide valuable references for evaluating the high-velocity impact resistance of such structures.

Dynamic impact and tensile strength characteristics of novel shear thickening fluid (STF)-treated fabric and modeling tensile strength using artificial intelligence

A series of shear thickening fluids (STFs) were prepared based on dispersed fumed silica in virgin polyethylene glycol (V/PEG) and modified PEGs by malonic acid (M/PEG) and tartaric acid (T/PEG). Rheological examination revealed that modification of PEG to a higher chain length of medium molecules remarkably improves STF peak viscosity and decreases the critical shear rate. High-velocity impact resistance of V/STF, M/STF, and T/STF-treated fabric was investigated at different layers and impact velocities and found significant improvement over neat fabric targets. Investigation of the results of two-layer samples showed the energy dissipation of V/STF, M/STF, and T/STF-treated fabrics at an impact velocity of 240 m/s is improved by 30.04%, 40.60%, and 46.06%, compared to the neat fabric, respectively. Furthermore, the tensile strength test revealed that these STFs fill the spaces between the fibers and make the fabric stronger and more resistant to breaking. In addition, a Linear/Nonlinear artificial intelligence regression analysis was performed. The results showed a strong correlation between composite mechanical response and speed. The proposed model can be further used to predict material behavior at other tensile speeds.

Effect of graphene oxide–iron oxide hybrid nanocomposite on the high-velocity impact performance of Kevlar fabrics impregnated with nanosilica/polyethylene glycol shear thickening fluid

In this paper, the influence of graphene oxide (GO) and GO–Fe3O4 hybrid nanocomposite (GFHN) as additives for nanosilica/polyethylene glycol shear thickening fluid (STF) was investigated on the fiber pull-out response and high-velocity impact performance of Kevlar fabrics. To fabricate GFHN nanofillers, the Fe3O4 nanoparticles were linked onto the graphene oxide surfaces using the electrostatic self-assembly method. The GO sheets and GFHN nanofillers were separately incorporated into STF containing fumed silica nanoparticles and the Kevlar fabrics were impregnated with the obtained STF-GO and STF-GFHN nano-mixtures. The pull-out test results of the impregnated Kevlar fabric indicated that the STF-GO nano-mixture decreased while the STF-GFHN nano-mixture increased the friction between the yarns of the impregnated fabric. This was in correlation with the high-velocity impact test results in which the STF-GO nano-mixture deteriorated while the STF-GFHN nano-mixture considerably improved the high-velocity impact resistance of the impregnated Kevlar fabric. The Kevlar fabric impregnated with STF-GFHN nano-mixture containing 0.4 wt% GFHN nanofillers experienced the maximum pull-out force and impact energy absorption with 163% and 73% improvements, respectively, compared to the neat fabric.

High-velocity impact resistance of stepwise gradient sandwich beams with metal foam cores

This paper aims to reveal the impact resistance of the graded sandwich beams subjected to high-velocity impacts experimentally. By using the one-stage gas gun system, the dynamic response and failure of the sandwich beams are analyzed by considering the effects of core gradient, impulsive loading, and boundary condition. The results show that the dynamic structural response of beams is noticeably influenced by the different initial failure mode under the fully clamped condition. The core gradient configuration is confirmed to have no significant effect on the impact resistance performance in terms of the dynamic central deflection, permanent deformation, and failure modes. Under the simply clamped condition, however, the core gradient effect is confirmed to be the predominant factor for the noticeably changed impact resistance performances of the sandwich beams. Due to the advantages on structural response and core compression, the graded sandwich beams have significantly better impact resistance than the uniform sandwich beam under the low-velocity impact. The negative correlation between this advantage and impulsive intensity indicates that impact resistance of the uniform sandwich beam is superior to that of the graded sandwich beams under the intensive impact. This study provides guidance of the gradient designation of the energy absorption sandwich structure and its subsequent engineering applications.

High velocity impact behavior of Hybrid composite under hydrostatic preload

The Hybridization concept creates a niche within the composite segment to customize materials for specific applications with reduced cost without sacrificing strength and durability. The composite structures develop strain during continuous operation, and any sudden impact on these preloaded parts might result in catastrophic accidents. Studying impact response during such conditions is essential in designing and developing structures. This study experimentally investigates the high velocity impact response of Hybrid (Carbon-Glass) composite under normal and hydrostatic preload conditions. Mechanical tests involving Tensile, Izod, and Charpy are conducted. High velocity impact testing is carried out with a vertical single-stage gas gun with additional provision for hydrostatic preloading. An oscilloscope with a laser source measures the initial velocity, and Photogrammetry using a high-speed camera measure the residual velocity of a projectile. The mechanical test results suggest that Hybridization resulted in a significant property enhancement. The high velocity impact resistance and energy absorption are higher for Hybrid under both normal and preloaded impact.

Parametric optimisation of shear thickening fluid treatment for ultra-high molecular weight polyethylene woven fabric

The shear thickening fluid (STF) treatment enhances the low and high velocity impact resistance performances of para-aramid woven fabrics for soft armour application. This research investigates the effects of important parameters on the STF add on and impact energy absorption with the aim to develop a hybrid soft armour. The STF add-on on ultra-high molecular weight polyethylene (UHMWPE) woven fabrics was varied by altering the silica particle size, dilution ratio of STF and padding pressure. The results of the full factorial design of experiment showed that the energy absorption is independent of the add-on. Further, a soft armour panel (SAP) was made from the STF treated woven fabric. The ballistic performance of the panel was evaluated in terms of back face signature (BFS) against a 9 × 19 mm lead core bullet and was compared to that of a weight equivalent untreated panel. A hybrid SAP with unidirectional (UD) laminates of UHMWPE as strike face layers and STF treated woven fabrics as backing layers was prepared, and the BFS was found to be equivalent to that of a SAP containing 100% UD laminates (∼30 mm). The results imply that a certain number of UD laminate layers can be replaced with STF treated flexible woven fabrics without compromising on the ballistic performance of SAP.

Ballistic impact experiments of titanium-based carbon-fibre/epoxy laminates

In this paper, high-velocity impact resistance of lightweight laminates with multi-layers of carbon-fibre/epoxy laminates sandwiched by two titanium alloy skins and aluminium alloy skins was extensively investigated by experiments with a total of 48 impact tests conducted. The ballistic limit of the titanium-based carbon-fibre/epoxy laminate was estimated to be between 241.6 m/s and 257.1 m/s. Impact velocity governed energy absorption and the corresponding damage modes were characterised and identified. The influence of fibre metal laminates configuration on the impact resistance was then experimentally investigated at a fixed impact velocity with full penetration in ten types of laminates. The results also showed that thicker skin and higher number of fibre layers favoured the specific energy absorption in the tested matrix.

Experimental and finite element study on high-velocity impact resistance and energy absorption of hybrid and non-hybrid fabric reinforced polymer composites

High-velocity impact resistance of FRP composites consisting of Kevlar, carbon and glass in hybrid and non-hybrid stacking sequences was studied through experimental and finite element analysis. Neat Kevlar/epoxy and Kevlar/glass/epoxy sandwich composites have the 1st and 2nd highest impact energy absorption percentage (100% and 97.99%, respectively). Carbon/epoxy composite exhibited the least energy absorption (38.78%). Other hybrid composites showed intermediate values of energy absorption in the range 38.58%–44.11%. Hybridization did not show any improvement in interlaminar shear strength of composites either. However, hybridizing Kevlar based composites with glass in the middle layer offered impact resistance close to Kevlar/epoxy composite while offering a 21% saving in material cost. Thus, such Kevlar and glass fabric-based sandwich composites possess a great potential as protective structures due to their ability to withstand impacts up to 200 m.s−1 velocity. These composites may also be considered for development of protective armor that are light-weight compared to conventional materials and more affordable. Finite element simulation results are in good agreement with that of experimental results with differences below 14%.

High-velocity impact resistance of doubly curved sandwich panels with re-entrant honeycomb and foam core

This work describes the high-velocity impact behavior of doubly curved sandwich panels. The sandwich panels are manufactured using carbon/fiber epoxy composite face sheets, polyurethane foam core and 3D-printed PLA plastic cellular auxetic (re-entrant) honeycombs. High-velocity impact tests are carried out by using a single-stage air gas gun test machine. A spherical steel projectile with the radius of 5 mm is impacted to the center of the specimens with the speed of 100 m/s. The experimental data are used to validate explicit finite element models of the doubly curved structures. An analytical model is also developed for the ballistic limit of the flat and doubly curved sandwich panels, and the analytical results are compared to those obtained from the numerical ones. Parametric numerical analyses of the high-speed impact of the curved sandwich panels are then carried out considering various radii of curvature of the panels. The results show that the energy absorption is increased as the curvature is decreased for the panels with both foam and re-entrant core. In addition, the core configuration provides a key role in the impact resistance of the sandwich panels. Re-entrant models show an increase in specific energy absorption (SEA) compared to the foam core types.

Design and finite element study of Kevlar based combat helmet for protection against high-velocity impacts

High-velocity impact-resistant helmets are used by police forces, law enforcement and military personnel, firefighters, as well as civilians working in construction, manufacturing, mining and material handling industries among other sectors as protection against impact damage caused by projectiles of various shapes and sizes. In this study, an attempt was made to investigate the impact-resistance of fiber-reinforced polymer composite based helmets through finite element analysis. The composite helmets were modelled in different sacking sequences using bi-directional woven fabrics such as Kevlar-129 (K), 3 K-Carbon (C) and EC9-Glass (G) fabrics as reinforcements and an epoxy matrix formulation. Investigation was focused to study the high-velocity impact resistance and energy absorption performance of composite helmets in hybrid and non-hybrid stacking sequences such as KKK, KGK, KCK, KCG and GCK subjected to high-velocity impact simulations at 398 m.s−1. It was observed that neat Kevlar and Kevlar-glass sandwich hybrid composite helmets withstood the projectile, while all other hybrid helmets were completely perforated during impact. It was also found that Kevlar-glass sandwich helmets offered cost savings of about 21% compared to neat Kevlar-epoxy composite. Hence Kevlar-glass sandwich composite can be used to develop protective helmets due to their attractive impact resistance properties and lower cost. The variation in helmet weight among all the considered composite material combinations was only about 5%.

Energy balance modelling of high velocity impact effect on composite plate structures

Purpose: In many military applications, composite materials have been used because of their high velocity impact resistance that helps absorption and dispersion energy. It is therefore used in armour and vehicles, aircraft and spacecraft that are subjected to impact of various shapes and velocities. Design/methodology/approach: In the theoretical part, the absorption energy equation for the sample was established by constructing an energy balance equation consisting of five types of energies, it is the compressive energy in the first region (the impact region), the tensile energy in the first region, the tensile energy in the second region, the energy of the shear plugging and the friction energy. Findings: It was found in the experiments that the tensile stress value increased by increasing the volume fraction of fibres to the polyester, and the value of compressive stress decreased. Also manufactured different types of impact samples with dimensions (20*20 cm2 ) and deferent thickness. The results were an increase in the amount of energy absorbed by increasing the ratio of the fibre to the polyester. It is found that the greatest effect in the equation of energy balance is the shear plugging energy, in which the value of the energy absorbed reached 38% of the total energy. And in the second degree friction energy, in which the value of the energy absorbed reached 27% of the total energy. while the other energies are relatively small but with important values, except for the tensile energy in the second region, the Kevlar-Polyester (40-60)%, so that the increase was more than four times the previous case. Research limitations/implications: Three types of reinforcing fibres were used: Kevlar, Carbon and Glass fibres with a matrix material as polyester. Six samples are made for tensile and compression testing, Kevlar-Polyester (30-70)%, Carbon-Polyester (30-70)%, Glass-Polyester (30-70)%, Kevlar-Polyester (40-60)%, Carbon-Polyester (40-60)% and Glass-Polyester (40-60)%. Practical implications: On the experimental part, experimental work tests were carried out to determine the mechanical properties of the samples such as tensile and compression tests as well as conducting the natural frequency test conducting the impact test by bullet to identify the effects and penetration incidence and compare this with the theoretical results. Originality/value: In this research high velocity impact is used with a bullet it diameter 9 mm, mass of 8 g, and a semi-circular projectile head with a specific velocity ranging from 210-365 m/s. The effect of the impact is studied theoretically and experimentally. The elastic deformation is increased for increasing the ratio of the fiber to the polyester and the depth of penetration is decreasing. The hybrid sample is affected in absorption energy and decreasing the penetration. Finally calculated for penetration behaviour theoretically and experimentally for different composite materials and comparison for the results calculated.

The Effect of Stacking Sequence on High-velocity Impact Resistance of Hybrid Woven Reinforced Composites: Experimental Study and Numerical Simulation

The Effect of Stacking Sequence on High-velocity Impact Resistance of Hybrid Woven Reinforced Composites: Experimental Study and Numerical Simulation

Experimental and Numerical Study of the Hybridisation Effect on the High-Velocity Impact Resistance of Thermoplastic Composites Based on Aramid Fabrics

One of the urgent tasks of the development of new protective structures is to improve the ballistic performance of thermoplastic composites reinforced with synthetic high-strength fibres. Hybrid composites based on various types of fibres or fabrics with different weaving could be a possible solution to this problem. This paper presents the results of computational and experimental studies of hybrid composites based on aramid fabrics with satin and plain weave structures. Numerical modelling based on the reduced ply-level approach was used for the design of hybrid composites. The results obtained during calculations were in good agreement with validation experiments.

Hygrothermal effect on high-velocity impact resistance of woven composites

The woven glass fiber reinforced composites (GFRP) subjected to high-speed impact is investigated to identify the hygrothermal aging effect on the impact resistance. Both the hygrothermal aged and unaged glass/epoxy laminates are subjected to different impact velocities, which is confirmed as a sensitive factor for the failure modes and mechanisms. The results show the hygrothermal aging effect decreases the ballistic limit by 14.9%, but the influence on ballistic performance is limited within the impact velocity closed to the ballistic limit. The failure modes and energy dissipation mechanisms are confirmed to be slightly influenced by the hygrothermal aging effect. The hygrothermal aging effect induced localization of structural deformation and degradation of mechanical properties are the main reasons for the composite undergoing the same failure modes at smaller impact velocities. Based on the energy absorption mechanisms, analytical expressions predict the ballistic limit and energy absorption to reasonable accuracy, the underestimated total energy absorption results in a relatively poor agreement between the measured and predicted energy absorption efficiency.

High velocity impact on composite sandwich panels with nano-reinforced syntactic foam core

Abstract In this work, an experimental investigation of the high velocity impact resistance of syntactic foam core composite sandwich panel has been undertaken. The syntactic foams filled with ceramic microballoons of three different sizes and three different volume fractions. Also, to enhance the matrix strength of the foam core, some specimens reinforced with nano particles. The high velocity impact tests have been carried out using a light gas-gun and a 10 mm blunt-head steel projectile and the ballistic limit was measured. The Impact behavior and the failure mechanisms are thoroughly investigated and also the absorbed energy during projectile perforation was correlated to the damaged area of specimens. The test results show that the ballistic resistance decreases with increasing the volume fraction of microballoons and the panel with 40% volume fraction of microballoons has the highest specific perforation energy. Moreover, nano-reinforcing the syntactic foam core increased the ballistic limit velocity up to 10%.

Analytical Prediction of High-Velocity Impact Resistance of Plane and Curved Thin Composite Targets

Resistance to ballistic impacts is a key requirement for an effective use of composite structures in many engineering applications. In fact, when fiber-reinforced composites are subject to high-velocity impacts (HVI), they are likely to suffer complete perforation, eventually causing the dramatic failure of the overall system. Moreover, elements with shielding requirements often feature nontrivial curvatures, so that their use in many engineering applications must undergo a precise evaluation of the effects of curvature on their resistance to impacts. The objective of the present work is to present an analytic formulation to model high-velocity impacts on both plane and curved (cylindrical and spherical) thin woven fabric composite targets, relying on the geometric and the elastodynamic characteristics of the target.