Ballistic Applications Research Articles

Composites in Ballistic Applications Focused on Ballistic Vests—A Review

The development of ballistic materials has improved very rapidly in the last few years. Body armor plays an important role in protecting individuals during military threats. Body armor can be divided into hard and soft variants depending on the trade-offs between protection levels and wearer agility. Current research aims to optimize strength-to-weight ratios by using different combinations of synthetic or natural fibers or their combinations to achieve increasingly demanding requirements for ballistic materials. Moreover, it examines the various types of fibers utilized in the construction of body armor, ranging from traditional materials like metal and ceramic to synthetic and natural fibers. This paper discusses ongoing research efforts aimed at further enhancing the performance of these materials, such as the incorporation of modified natural fibers into advanced composite systems. The review provides a comprehensive analysis of the current state of the materials utilized in ballistic protection.

Agro-Based nanoparticles composite: A novel approach for enhanced ballistic applications

The field of material science has witnessed a paradigm shift with the emergence of agro-based nanoparticles composites demonstrating remarkable potential for advanced applications. Agricultural by-products, such as cellulose, lignin, and chitin, are selected as the base materials due to their abundance, renewability, low adverse environmental impact and acceptable mechanical properties. The developed composites exhibits superior specific mechanical properties compared to traditional materials. This review explores the synthesis, characterization, and application of agro-based nanoparticles in composites development for ballistic purposes. The eco-friendly nature and synthesis of agro-based composite aligns with the current sustainability goals, offering a green alternative to conventional materials being used in ballistic applications. The utilization of agricultural by-products not only mitigates environmental concerns but also promotes the circular economy by repurposing waste materials into high-value products. This review presents a novel approach in the field of ballistic materials by harnessing the potential of agro-based nanoparticles composites. The superior specific mechanical properties make this composite material a promising candidate for ballistic applications, thereby, opening avenues for sustainable advancements in defense and security technologies. Keywords: Agro-based, Nanoparticles, Composites, Green Technology, Ballistic Application.

Damage of thin target plates impacted by conical projectiles with varying apex angles in ballistic application: experimental, FEA and ANN integrated approach

In the current study, an experimental setup consisting of smoothbore 30-caliber powder gun was employed to launch spherical projectiles (3 g/ϕ9) in the ballistic range of velocities from 500 to 1700 m/s and obliquity (0, 33 and 65°), impacting 2 mm thin Steel 1006 target plates. Crater dimensions (major and minor dia.) obtained from series of FE simulations run for the above configuaration was validated by corresponding experimental data. Subsequently, a fullscale 3D FE model considering 8-noded hexahedral elements was used to discretize SS304 conical projectiles (replacing spherical projectile) with various apex angles viz. 40°, 60°, 80° and 100° impacting on single (3 mm) and double layer (1.5 mm each) steel 1006 targets (replacing 2 mm target) in LS dyna. The material behavior was characterized using J–C strength and damage models, along with Gruneisen Equation of State. An erosion algorithm was used in the explicit FE code LS-DYNA to remove undesirable elements. In the next stage, Adam and Nadam optimizers have been employed in ANN models developed using Python code within the Tensor-Flow framework. The Keras Tuner library in the Tensor-Flow framework was used for hyper parameter tuning. The ANN models trained using simulation data successfully predicted the residual KE of conical projectiles with intermediate apex angles of 90°, 70°, and 50° across twelve different impact scenarios. The models with Adam and Nadam optimizers achieved mean squared error (MSE)/coefficient of determination (R2)/mean absolute percentage error (MAPE) values of 109.44/0.998/6.72 and 91.19/0.998/7.76, respectively.

Ballistic performance of aluminum alloy plates with polyurea coatings for high-speed train structures

Polyurea coatings have been widely promoted in explosion and ballistic impact protection applications due to their excellent hyper-elasticity performance. In rail transportation, high-speed trains face potential impact threats from track ballast, which can affect the strength performance of the base material. To address these challenges, we examined the ballistic performances of aluminum alloy plates with polyurea coatings under large-scale impact (>30 mm). Four different configurations of target plates were investigated: A, P-A, A-P, and P-A-P. We fabricated samples and performed dynamic impact tests using an air cannon system to demonstrate the feasibility. Results show that ballistic performance is significantly improved by applying polyurea coatings on aluminum alloy plates. In particular, the growth rate of limit velocity of configuration A-P, P-A, and P-A-P to that of configuration A are 5.5 %, 19.4 %, and 22.8 %, respectively. The enhancement mechanism was further uncovered through stress wave propagation analysis and lateral energy diffusion effect. Explicit formulas for predicting the limit velocity and residual velocity were derived and demonstrated with reasonable accuracy over a wide range of parameter spaces. The observed enhancement in ballistic performance through polyurea coatings on aluminum alloy plates offers promising ways to design and implement more resilient and impact-resistant high-speed train structures.

Comparison of iron aluminide Fe3Al with armour steel in ballistic behaviour

Intermetallic aluminide compounds possess several potential advantages compared to alloyed steels, like enhanced oxidation resistance, lower density and the omittance of critical raw materials. Iron aluminides, compared to other transition metal–aluminides of TM3-Al type, although having a higher density compared to titan-aluminides, have a lower density compared to nickel-aluminides, but also a higher ductility than both alternatives, making this material potentially effective in ballistic protection application. Density–wise, this material may be a worthy alternative to armour steels, which was the aim of this study. Two materials, Fe3Al intermetallic compound (F3A-C) and Armox 500 armour steel were ballistically tested against tungsten-carbide (WC) armour-piercing ammunition, in accordance with STANAG 4569. After ballistic testing, microhardness and metallographic testing were performed, revealing differences in strain hardening, crack propagation mode and exit hole morphology. F3A-C ballistic resistance is similar to that of armour steel, in spite of the lower tensile and impact mechanical properties, relying on a considerably higher strain hardening rate, thermal properties and a lower density.

Effectiveness of ballistic exercises for increasing upper body explosive power in physical education lessons for university students

Background and Study Aim. Explosive power is an important element of fitness levels, with fast muscle contractions being required in most physical activities. Study implements and verifies the effects of ballistic exercises with medicine balls of various weights on upper body explosive strength for non-sporting university students. Material and Methods. The study involved 184 male and 143 female undergraduate students, all 21 years old. These students had no medical contraindications to participating in the activities required by the physical education program. The development of upper body explosive strength was conducted using ballistic exercises, specifically various types of medicine ball throws, over one academic year. The evaluation comprised six tests: Overhand Ball Throw, Overhead Medicine Ball Throw-forward, Overhead Medicine Ball Throw-backward, Medicine Ball Chest Throw, Shot Put - Track and Field, and 30 s Plyometric Push-Ups. These tests were scheduled at three different times during the academic year: October, December, and May. Results. The results of the Analysis of Variance (ANOVA) with repeated measurements indicate F values associated with statistically significant thresholds (p < 0.05). In contrast, partial eta squared (η²p) values demonstrate a stronger effect of ballistic exercise application for the male group. Significant improvements in results were observed for both genders from one test to another. The differences were notably larger between the test conducted before the winter holiday (December) and the test at the end of the second semester (May) compared to those between the test at the beginning of the academic year (October) and the one before the winter holiday (December). This pattern indicates a clear improvement in muscle strength in the second semester (January-May). The only test where high percentages of men, and especially women, encountered problems was the 30-second Plyometric Push-Ups. In the final tests, 10% of males and 40% of females scored zero. Conclusions. Ballistic exercises based on various medicine ball throws prove to be an attractive and effective solution to improve upper body muscle strength for non-sporting university students. The application of these exercises can significantly enhance physical education programs by providing clear benefits in terms of strength development. This is particularly evident in environments aimed at general student populations rather than athletes. Furthermore, while the exercises are broadly beneficial, they may require modifications to address the challenges some students face.

Comparative study of effect of fragment nose shapes on damage characteristics of thin target plate in ballistic applications

Experimental and numerical investigations in ballistic applications have predominantly focused on determining the ballistic limit of target plates for various projectile shapes. However, limited attention has been given to the influence of projectile nose shapes at high impact velocities. To address this gap, 3D FE simulations were carried out on a 1 mm thin target plate using J-C material model, the Gruneisen equation of state (EOS), an erosion contact algorithm, and the explicit FE code LS-DYNA. The simulations involved impact of fragments of equal mass but different nose shapes. The results revealed a significant influence of fragment shape on both the ballistic limit and overall plastic deformation of the target plate. Particularly, the target plate impacted by a hexagonal pyramid fragment shape exhibited the highest ballistic limit and global plastic deformation. Further, it was also observed that at higher impact velocities, the former fragment shape caused the maximum damage to the target plate, while at lower impact velocities, the cubical fragment shape demonstrated the highest lethality. This difference in target damage is known to be governed by the energy required to erode the target and fragment material. The results from the current study offers valuable insights into how different fragment shapes influence the damage inflicted on target plates in ballistic scenarios. The findings presented in this study also offer guidance on selecting suitable fragment shapes for future use in Fragment Generator Warheads (FGW) in order to maximize the damage or lethality inflicted on targets.

Interfacial reinforcement of aramid composites through amino SiO2 interphase for ballistic application

Interfacial reinforcement of aramid composites through amino SiO₂ interphase for ballistic application

Investigation on para‐aramid fiber‐reinforced poly‐ether ketone‐ketone high‐performance composite for ballistic application

AbstractThis investigation highlights the performance of high‐performance polymeric composite for ballistic application. Therefore, reinforcement of para‐aramid fiber in poly‐ether‐ketone‐ketone (PEKK) resin film has been made. The surface of PEKK and para‐aramid fiber was modified by low‐pressure plasma to enhance the surface energy of the polymeric film and reinforcement fiber. The polymeric composite was manufactured by compression molding with a pressure of 2 bar, temperature of 310°C with holding time of 15 min. Due to low‐pressure plasma treatment of PEKK film and para‐aramid fiber, the tensile strength of the composites increases considerably. In the accelerated aging test, the tensile specimens are dipped into concentrated HNO3 and NaOH medium for 15 days. It is observed that there is a decrease in tensile strength. The ultimate tensile strength (UTS) of the virgin specimen was compared to the environmentally aged for 15 days and in this case, also there was a decrease in tensile strength. Two types of composite panels were made (i) 25 layers of PEKK film with 24 layers of para‐aramid fabric and (ii) 45 layers of PEKK film with 44 layers of para‐aramid fabric with 15 mm × 15 mm. The composite panel was tested with four 9 mm handgun bullets fired from a distance of 5 meters with a speed of 430 m/s. In the case of 25 layers of PEKK film with 24 layers of para‐aramid fabric, the composite failed under ballistic test, however, in the case of 45 layers of PEKK film with 44 layers of para‐aramid fabric, the composite was successful under ballistic test.Highlights Film stacking method of PEKK and Aramid fiber. Ballistic composite panel with layers of PEKK and Aramid fiber. Enhancement of mechanical properties of the composite panel with plasma surface treatment. Ballistic testing of composite panel.

State-of-the-Art Polyurea Coatings: Synthesis Aspects, Structure-Properties Relationship, and Nanocomposites for Ballistic Protection Applications.

This review presents polyurea (PU) synthesis, the structure-properties relationship, and characterization aspects for ballistic protection applications. The synthesis of polyurea entails step-growth polymerization through the reaction of an isocyanate monomer/prepolymer and a polyamine, each component possessing a functionality of at least two. A wide range of excellent properties such as durability and high resistance against atmospheric, chemical, and biological factors has made this polymer an outstanding option for ballistic applications. Polyureas are an extraordinary case because they contain both rigid segments, which are due to the diisocyanates used and the hydrogen points formed, and a flexible zone, which is due to the chemical structure of the polyamines. These characteristics motivate their application in ballistic protection systems. Polyurea-based coatings have also demonstrated their abilities as candidates for impulsive loading applications, affording a better response of the nanocomposite-coated metal sheet at the action of a shock wave or at the impact of a projectile, by suffering lower deformations than neat metallic plates.

Development of Kevlar-ultrahigh molecular weight polyethylene composites for ballistic applications

Development of Kevlar-ultrahigh molecular weight polyethylene composites for ballistic applications

Improving the mechanical performance of low graphene content epoxy nanocomposites: investigation of hybrid and chemically modified nanofillers

Graphene is a promising nanofiller for producing polymer nanocomposites with enhanced mechanical, electrical, thermal, electromechanical, and flame retardancy properties, leading to applications in aerospace, automotive, ballistics, medicine, electronics, and smart materials. Solvent-assisted top-down methods, including mechanical exfoliation of graphite, show great potential for scale-up and mass production of graphene dispersions for use in the fabrication of nanocomposites. However, these approaches can suffer from poor efficiency, which limits the concentrations of graphene/polymer dispersions that can be produced using in situ methods. As such, it is important to find new ways of making more effective use of these low concentrations of graphene nanofillers. Possible approaches include chemical modification of the graphene or finding synergies with other nanofillers to form hybrid nanocomposites. In this work, we demonstrate results that make use of each approach. Specifically, we demonstrate a low-cost and simple method for producing carbon nanotube dispersions and creating hybrid nanocomposites with substantial enhancements to mechanical properties. We also extend the scope of our previously reported semi-in situ exfoliation method by demonstrating its application in the production of a nanocomposite that incorporates chemically modified graphene. The superior mechanical properties exhibited by the nanocomposite are attributed to increased interaction strength between the polymer and nanofiller.

Determination of the Worst Case for the Ballistic Test of the Soft Armour System Using the 9mm FMJ Bullets Differing in the Structure

Abstract Ballistic tests require significant rigor and the development of a worst case model during the research processes. The purpose of this study was to evaluate the effect of bullet type (manufacturer) on V50 and Behind Armor Blunt Trauma (BABT) results for two ballistic applications: p-aramid and UHMWPE fibre. The results confirmed the thesis that the source of the bullets implies the test results obtained in terms of the number of penetrated layers in the ballistic system, backface signature deformation profiles (p-BFS) and the level of residual energy transferred to the user of the personal protection.

B4C-SiC composites with tuneable mechanical properties: Role of Al2O3 - Y2O3 sintering additives

While outstanding properties of boron carbide (B4C)-silicon carbide (SiC) composites make them potential candidates for ballistic and wear resistance applications, the applicability is rather limited due to processing challenges to obtain high density and superior mechanical properties. In the present work, B4C-10 wt% SiC composites are spark plasma sintered without additives and with 6 wt% (Al2O3 -Y2O3) additives at 1600 °C, 1700 °C and 1800 °C. When sintered at 1600 °C, the relative density increased from 94% for the composites without additives to ∼99% with Al2O3-Y2O3 additives. The formation of liquid phase comprising Al-Y-Si-O improved density and mechanical properties of the composites. TEM analysis of the composite sintered with (2 wt% Al2O3 - 4 wt% Y2O3) additives at 1800 °C confirmed clean grain boundaries between B4C, SiC and liquid phase precipitates. When sintered at 1700° C, the indentation fracture toughness increased from 4.3 MPa.m0.5 for the composite without additive to 6.0 MPa.m0.5 for the composite with 6 wt% Al2O3 additive due to increased instances of crack splitting, bridging and deflection.

Finite Element Analysis of Ceramic–Composite Structures for Ballistic Applications: Effect of Ceramic Thickness and Cell Structure

This study employs finite element simulation to conduct a numerical modeling of ceramic–composite structure armors. The numerical armor models consist of a ceramic plate and a composite backing plate. Alumina oxide and silicon carbide ceramic materials with two different cell structures are used: hexagonal and square cell structures, respectively. A Kevlar composite is used as the back plate. The ceramic plate's thickness is altered among 7, 8, and 9 mm to explore its influence on the ballistic performance of the armors. The damage fracture is compared with experimental results, and the ballistic resistance is further examined by determining the projectiles’ velocities at the conclusion of the simulation and the evolution of the average velocity during the impact period. The findings of the numerical modeling reveal that the ceramics sustain damage consistent with the experimental damage. However, as perforation is observed in every sample, the overall performance of the samples is deemed unsatisfactory.

Design and Development of Novel AA7075-T6 based Armor Plate through Numerical and Experimental Approach

The materials used for ballistic applications have always taken a special spot in the manufacturing and study of protective amours. Although metals like steel provide adequate ballistic protection, they compromise the mobility of the soldier and since high mobility is a primary requirement for soldiers during combat. Therefore, at present most of the researchers are currently focusing on materials with properties like high impact resistance and high strength to weight ratio. In recent times, Aluminum alloys are recognized as the alternative materials which can provide good impact resistance and have a high strength to weight ratio and having better corrosion resistant properties which ultimately make it a suitable material for several military applications. In this research, one of the toughest aluminum alloys AA7075-T6 is considered for designing an armor plate and studied for its ballistic resistance. Initially, the monolithic AA7075-T6 alloy of 18 mm was tested for its ballistic resistance limit and further it is designed with the ceramic plate of 3 mm and base alloy AA7075-T6 of 15 mm was tested to evaluate. Later the monolithic alloy of 18 mm was surface reinforced up to a thickness of 3 mm with different types of reinforcements and evaluated the bullet residual velocity after penetration of the armor piercing projectile. Numerical simulation was conducted using the prominent non-linear dynamic analysis software i.e., Ansys AUTODYNE version 19.2 and the respective values for the surface reinforced metal matrix composites revealed excellent results for the depth of penetration and residual velocity of the projectile.

Influence of Tic on Density and Microstructure of Al2O3 Ceramics Doped with Nb2O5 and Lif

Ceramic matrix composites are widely studied in the ballistic sector due to their high hardness, fracture toughness, and improved ballistic performance in multilayer shielding systems. However, the presence of dopants in ceramics can pose challenges during processing and potentially compromise the final properties of the sintered material. This study focused on the ceramic processing of Al2O3-based ceramic matrix composites by adding 4 wt.% Nb2O5 (niobium oxide), 0.5 wt.% LiF (lithium fluoride), and 38.5 wt.% TiC (titanium carbide). The composites were produced using cold uniaxial pressing and conventional sintering at 1400 °C for 3 h. The composites were characterized using Archimedes’ principle and scanning electron microscopy (SEM). The results revealed that the samples to which TiC was added exhibited low initial densities, indicating that the applied pressure of 50 MPa during cold pressing was insufficient to adequately densify the green bodies. Moreover, the presence of TiC led to a significant reduction in densification, making it challenging to apply a conductive coating for SEM analysis. Adjustments to the intensity of the electron beam were necessary to conduct the analysis successfully. Conversely, the samples to which TiC was not added exhibited high density values in the green state and yielded consistent results after sintering in line with previous research, indicating a satisfactory degree of sintering in the absence of TiC. These findings highlight the importance of carefully considering the addition of TiC in ceramic matrix composites during processing, which can have a significant impact on densification and subsequent material properties. The results contribute to the understanding of processing parameters with regard to the production of ceramic composites with desirable characteristics for ballistic applications.

Material design for ballistic applications: A numerical analysis of surface reinforced AA6061-T6 metal matrix composite

Several studies have been carried out to develop lightweight materials with enhanced ballistic properties to develop appropriate armor shields for the military to increase system mobility while maintaining safety. Of all the lightweight materials, aluminum is the better alternative because of its high strength-to-weight ratio, stiffness, resistance to corrosion, etc. Ballistic protection against projectiles can be aided further with the help of suitable ceramics. They combine relatively high strength and elastic modulus with high-temperature capability and general freedom from environmental attack, making them attractive as reinforcements in high-temperature structural materials. AA6061-T6 is considered the most commercially available of all aluminum alloys and has better impact toughness properties. Therefore, this research focuses mainly on evaluating the ballistic protection of the AA6061-T6 with 18 mm thickness using different reinforcements. Numerical analysis was conducted initially on the monolithic AA6061-T6 18 mm thickness plate and then with the 3 mm ceramic plate at the front and the base as 15 mm thick monolithic AA6061-T6 plate and evaluated the ballistic resistance individually. Finally, different reinforcements are induced in the top 3 mm thick AA6061-T6 layer and the base as the 15 mm thick AA6061-T6 plate and compared with the ceramic armor plates. The results revealed a prominent residual velocity after the bullet perforation into the target armor plate.

Ballistic Energy Absorption of Thermally Aged DGEBA/TETA System and Fique-Fabric Reinforced Epoxy Composite

Abstract: For many applications, such as vests or parts of vests, the fibers are used in fabric, mat, or mesh. Ballistic resistance properties are also improved by the development of special fabrics architectures. It is known that heat and oxygen are the main factors in the aging process of polymers. The mechanisms of aging by oxidation can be investigated by monitoring the mechanical properties of a material exposed to prolonged aging in an oven, which is called the accelerated aging process by thermal oxidation. In previous studies, the epoxy matrix composite reinforced with 40% by volume of fique fabric, already tested and with good ballistic performance, was developed and proposed for individual ballistic protection applications. However, the impact of different environmental conditions on the dynamic properties of the composite has not been studied. Therefore, the present study, for the first time, aimed to apply accelerated weathering through high temperature to the composite, as well as to the epoxy matrix, aiming to evaluate the influence of aging.

Nanocoatings for ballistic applications: A review

Abstract The manufacturing of ballistic impact-resistant (BIR) body armours has evolved over the years with the aim of reducing their weight and enhancing their energy-absorbing capacity upon ballistic impacts. The incorporation of nanoparticles into advanced BIR body armour systems is considered one of the promising techniques. The methods employed in incorporating various nanoparticles in the manufacturing of textile-based body armour systems face a research gap in the optimisation of the associated parameters. This article discusses the mechanism involved in the energy absorption of composites and nanocomposites upon ballistic impact. The current review article highlights the chemical, physical, and mechanical properties of various nanoparticles incorporated into BIR body armour systems. BIR nanocomposites consisting of carbon nanotubes, graphene nanoplatelets, nano-silica, nanoclays, nano-alumina, etc., have been discussed herein. In addition, the significance of various techniques for the dispersion of these nanoparticles was also highlighted. Various methods, such as sol–gel, PVD, CVD, thermal spray, and electroless methods for coating the nanoparticles on the surface of the fibre/fabric were also discussed.