Ballistic Materials Research Articles

Laser-Induced Damage of UHMW-PE-Based Layered Ballistic Materials

Laser-Induced Damage of UHMW-PE-Based Layered Ballistic Materials

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.

Relationship between elastic properties and energy absorption of different types of aramid and UHMWPE composites used in ballistic protection

This study aimed to analyse composite materials' mechanical and elastic properties from various aramid and ultra-high- molecular-weight polyethylene fabrics used in ballistic armour materials. Furthermore, a comprehensive analysis was conducted to examine the correlations between the energy absorption data acquired from the low-velocity impact, dynamic compressive, and ballistic impact V50 tests performed in our prior investigations and the tensile test outcomes of these composites. The research revealed a notable correlation between Poisson's ratio, elasticity modulus values, and energy absorption capability. The composite material with the lowest Poisson ratio exhibited superior energy absorption performance in all tests. Composites reinforced with unidirectional textiles have attracted attention due to their low Poisson ratio and high elasticity modulus values, resulting in exceptional energy absorption capability.

Investigation of microstructure and mechanical properties of 45KH2NMFBA steel samples after thermal exposure

The analysis of the structure of ballistic materials was carried out and the optimal mechanical properties necessary to ensure the best bullet resistance and durability of armored steel were selected. A study of 45X2NMFBA armor steel was carried out under various heat treatment modes. The optimal modes of heat treatment have been determined to ensure an increase in mechanical properties. It was found that with an increase in the cooling rate of steel, a finer‑grained structure is formed, and an increase in the quenching temperature leads to an increase in the grain of primary austenite. The results of optical microscopy and mechanical properties of the studied steel samples are presented

Advanced Tactical Helmet for Military Use

Abstract: Advanced features on a tactical helmet designed for military use. Soldiers in today's military operations must have improved situational awareness, strong communication skills, and superior protection when fighting. A new generation of tactical helmets with enhanced features is required because the standard helmets now in use do not adequately fulfil these criteria. To improve army performance and survivability The helmet has several extra features in addition to its extensive ESP32 CAM for real-time data visualization, communication systems for seamless inter-squad communication, and improved ballistic protection materials. Among these characteristics include the incorporation of a helmet camera's First-Person-View (FPV) live video feed into a base station, along with the base station's face detection capabilities for enhanced identification. SolidWorks was used in the design process to produce a unique 3D-printed helmet, while ESP32 and ESP8266 were used to power a custom mainboard that effectively controlled the helmet's functions. this creative solution aims to significantly improve military operations, increase survivability, and ensure the safety of soldiers on the battlefield.

Advanced Transparent Glass‐Ceramics via Laser Anisotropic Nanocrystallization

AbstractTransparent glass‐ceramics, merging the attributes of both glass and ceramics, have diverse applications in ballistic protection, armor materials, dentistry, light‐emitting diode, and optical domains. A limitation of conventional methods for glass‐ceramic fabrication is their inadequacy in precisely controlling the morphology of crystallization, consequently constraining their prospective advancements in diverse areas. Here, a method that facilitates precise control over the formation and growth of polarization‐dependent nonperiodic anisotropic nanocrystals, with a short axis ranging from 15 to 280 nm, in Li2O‐Al2O3‐SiO2 (LAS) glass is proposed. The method utilizes the principles of near‐field anisotropy between light and matter, building upon the classical nucleation‐growth model of glass crystallization. Notably, the glass‐ceramics possessing laser‐induced nanocrystals within the Rayleigh size regime showcase an impressive 99.7% transmittance in the visible and near‐infrared wavelengths. Additionally, the glass‐ceramics with non‐periodic anisotropic nanocrystals macroscopically exhibit form‐birefringence properties, thus enabling transparent optical applications, such as polarization elements, geometric phase elements, and multi‐dimensional optical data storage. This work opens up new avenues for morphological manipulation of nanocrystallization, with potential applications in optics, nanophotonics, functional glass‐ceramics, and high mechanical performance devices.

Temperature and Strain Rate Related Deformation Behavior of UHMWPE Fiber-Reinforced Composites.

As they possess the qualities of high specific strength, high specific modulus, high specific energy absorption, and excellent designability, ultra-high molecular weight polyethylene (UHMWPE) fiber-reinforced composites have gradually replaced traditional materials such as ceramics and steel plates as the main ballistic protection materials. Using an improved test method, the uniaxial tensile tests of UHMWPE fiber-reinforced composites at two strain rates of 10-4 s-1 and 10-2 s-1 and a temperature range from -20 °C to 80 °C are carried out to study the effects of strain rate and temperature on the tensile behavior of UHMWPE fiber-reinforced composites. The experimental results indicate that the tensile responses exhibit nonlinear characteristics and the sensitivity of strain rate and temperature. The yield strength and modulus decrease with increasing temperature and increase with the increase in strain rate. A phenomenological viscoelastic constitutive model composed of a nonlinear spring and a nonlinear Maxwell element is proposed to characterize the temperature and strain rate dependent deformation behavior of UHMWPE fiber-reinforced composites before yielding. The results show that the model can accurately predict the tensile nonlinear viscoelastic responses of UHMWPE fiber-reinforced composites before yielding over a wide temperature range under quasi-static loading.

Study on the mechanical properties and ballistic resistance of interface-modified fabrics with environmentally friendly shear thickening liquid

Based on the modification of industrial solid waste and surface grafting of functional groups to prepare new ballistic composites with green shear thickening functionality, ammonia-modified silica (NH4-SA) particles were successfully prepared from industrial solid waste through APTMS surface modification, and the modified NH4-SA was used as the shear thickening dispersed phase to regulate the green shear thickening solution, and in order to better achieve the grafting loading of the particles of the dispersed phase, the aramid fabric (AF) was metal ion modified. Ballistic resistance was tested by combining a solid waste-based modified shear thickening fluid (NH4-SA@STF) with a metal ion modified AF fabric. Characterization tests confirmed that NH4-SA@STF exhibited a significant shear thickening effect due to the addition of reactive functional groups on the surface of NH4-SA. Yarn pull-out tests showed that NH4-SA@STF/Fe-AF had a 4-fold increase in pull-out force and better friction properties compared to AF fabrics. Ballistic tests demonstrated that NH4-SA@STF increased the ballistic limiting velocity (Vbl) of AF fabrics from 52 m/s to 99 m/s. Both layer impregnation modification and individual impregnation treatment of each layer showed strong ballistic performance, indicating that NH4-SA@STF/Fe-AF composites exhibited superior ballistic performance compared to AF fabrics. The doping of NH4-SA enhanced the friction between the yarns and increased the load-bearing area of the fabric, resulting in improved ballistic performance of NH4-SA@STF/Fe-AF composites. The study successfully achieved the regulation of ballistic properties in NH4-SA@STF/Fe-AF composites, providing a promising approach for the development of new ballistic materials with green shear thickening functionality.

Graphene nanoribbon woven fabric against the impact of a cylindrical projectile

Graphene nanoribbon woven fabrics (GNWFs) with excellent mechanical properties are promising for ballistic armor materials. The dynamic response of single-layer and bilayer GNWFs under nano-projectile impact at high-speed (4–5 km s−1) is investigated by molecular dynamics simulations. Results show that the woven structure is determined by the bandwidth and gap spacing, which influences the deformation/fracture and motion coupling effects of the crossed nanoribbons and the ballistic performance of GNWF. Owing to the perturbation of the van der Waals (vdW) interface between nanoribbons, the specific penetration energy of GNWFs reaches 16.02 MJ kg−1, which is much higher than that of single-layer graphene (10.80 MJ kg−1) and bilayer graphene (10.07 MJ kg−1). The peculiarities of woven structure minimize the damage of GNWFs, on the one hand, the reversibility of vdW interactions and the entanglement of nanoribbons provide GNWFs a certain self-healing ability. On the other hand, the porous nanostructure of twist-stacked bilayer GNWFs tends to be uniform and dense with the twist angle, which improves the impact resistance. This study provides more understanding of the ballistic properties of GNWFs and the design of nano-fabrics based on two-dimensional materials.

New Approach for Manufacturing Ti–6Al–4V+40%TiC Metal-Matrix Composites by 3D Printing Using Conic Electron Beam and Cored Wire. Pt. 2: Layered MMC/Alloy Materials, Their Main Characteristics, and Possible Application as Ballistic Resistant Materials

Bilayer samples comprised of hard metal-matrix composite top layer and ductile 10 mm Ti–6Al–4V plate are produced with 3D printing by conical electron-beam method using specially prepared core (powder) wire that allows forming hard top layer of metal-matrix (Ti–6Al–4V) composite (MMC) reinforced by means of fine TiC particles with thickness up to 4 mm. Ballistic tests performed with 7.62×51 AP ammunition show a good ballistic resistance of this protective structure, i.e., it is not perforated. Only minor penetration and partial fracture are occurred exclusively in the surface MMC layer. Either no traces of plastic deformation are found at the boundary with the base layer or inside it that indicates that the MMC layer absorbs the entire impact energy of the projectile. Based on studies of the fine structure and texture of the interface between the layers, a reasonable assumption is made that wavy geometry of MMC layer provides additional deflection and scattering of stress waves generated during impact. Comparing the results of ballistic tests of various metallic materials, it is concluded that the 3D-printed bilayer material consisting of the upper Ti–6Al–4V + 40% TiC layer and the base Ti–6Al–4V layer has an undeniable advantage in ballistic performance when it is tested with cartridges of this type.

Ballistic characterization of additively manufactured extrusion deposited thermoplastic composite plates

Additive manufacturing (AM) is rapidly emerging in high performance applications such as army ground vehicles, automotive and transportation. However, the response of AM parts/components to extreme loading such as high velocity impacts is less studied. In this work, the performance under ballistic impact of AM panels is evaluated using a medium velocity gas gun, generating projectile velocities up to 400 m/s. The preferential print orientation properties are considered in order to evaluate whether the panels exhibit isotropic or anisotropic behavior under impact. Surface morphology is investigated by milling the beads smooth on samples and comparing the impact on as-printed samples to those that are smoothed. The effect of nickel chromium micron (nichrome) wire embedded in the AM panels (during print) of polycarbonate-carbon fiber (PC-CF) and polycarbonate-glass fiber (PC-GF) are explored. Thermoplastic polyurethane-acrylonitrile butadiene styrene/carbon fiber (TPU-ABS/CF), Acrylonitrile butadiene styrene-carbon-fiber (ABS-CF) AM samples absorbed >50% of the impact energy. The ballistic performance was noted to be in the following order – ABS-CF > TPU-ABS/CF > PC. Scanning electron microscopy (SEM) was conducted to study the interface between the nichrome wire and the polymer-fiber matrix. This work is the first of its kind exploring into the capabilities of AM panels as ballistic materials. This study leads the way for developing AM panels that are easily manufactured and exhibit superior ballistic resistance.

A shield of defense: Developing ballistic composite panels with effective electromagnetic interference shielding absorption

The primary goal of this study is to develop cost-effective shield materials that offer effective protection against high-velocity ballistic impact and electromagnetic interference (EMI) shielding capabilities through absorption. Six fiber-reinforced epoxy composite panels, each with a different fabric material and stacking sequence, have been fabricated using a hand-layup vacuum bagging process. Two panels made of Kevlar and glass fibers, referred to as (K-NIJ) and (G-NIJ), have been tested according to the National Institute of Justice ballistic resistance protective materials test NIJ 0108.01 Standard-Level IIIA (9 mm × 19 mm FMJ 124 g) test. Three panels, namely, a hybrid of Kevlar and glass (H–S), glass with ceramic particles (C–S), and glass with recycled rubber (R–S) have been impacted by the bullet at the center, while the fourth panel made of glass fiber (G-S) has been impacted at the side. EMI shielding properties have been measured in the X-band frequency range via the reflection-transmission method. Results indicate that four panels (K-NIJ, G-NIJ, H–S, and G-S) are capable of withstanding high-velocity impact by stopping the bullet from penetrating through the panels while maintaining their structural integrity. However, under such conditions, these panels may experience localized delamination with variable severity. The EMI measurements reveal that the highest absorptivity observed is 88% for the K-NIJ panel at 10.8 GHz, while all panels maintain an average absorptivity above 65%. All panels act as a lossy medium with a peak absorptivity at different frequencies, with K-NIJ and H–S panels demonstrating the highest absorptivity. In summary, the study results in the development of a novel, cost-effective, multifunctional glass fiber epoxy composite that combines ballistic and electromagnetic interference shielding properties. The material has been developed using a simple manufacturing method and exhibits remarkable ballistic protection that outperforms Kevlar in terms of shielding efficiency; no bullet penetration or back face signature is observed, and it also demonstrates high EMI shielding absorption. Overall, the materials developed show great promise for various applications, including the military and defense.

Quantification of time-dependent deterioration in mechanical property and ballistic performance through Cunniff Number of poly (p-phenylene terephthalamide) fibers under UV irradiation

Poly (p-phenylene terephthalamide) fibers, a crucial constituent of soft body armor, experience significant deterioration in mechanical and ballistic performance due to UV exposure. However, photo-degradation by UV radiation involves complex chemical reactions and the difficulty in estimating the extent of damage that restricts the development of the predictive aging models or kinetics in such fibrous materials. Hence in this work, the photo-degradation kinetics of poly (p-phenylene terephthalamide) or KF-fibers is quantified by correlating the degradation behavior of different properties with time, thereby assessing the useful performance span of the UV-aged (UV-KF) fibers. The experimental trends indicate three stages of deterioration of any property (modulus, extension at break, Cunniff Number and crystallinity), i.e., an exponential decline followed by an increase over a short duration and finally, a steady and continuous drop. The suitable performance period of UV-aged fibers is estimated based on the initial two stages and presented as ‘favorable property region’ or ‘FPR-zone.’ Changes in V50 ballistic limit, theoretically derived from Cunniff Number, are also estimated, which show a good agreement with the literature data. It reveals that the energy absorption capacity of UV-KF fibers corresponds to initial two years as a span of considerable ballistic protection before continuing to function at 50% of its original protection level for lower aging temperatures. Besides, the apparent activation energy for all the studied properties is correlated to the microstructural and physico-chemical aspects. It indicates that relative changes in molar mass by bond scission/rearrangement and alterations in crystallinity are proportionally related to the degree of variation in modulus and extension at break, thus affecting the wave-velocities in terms of Cunniff Number. The proposed degradation model further can be extended to determine the rate of degradation and lifetime of various ballistic materials under other environmental conditions.

Energy balance model to assess the resistance of ballistic protection materials

NATO standards "AEP-2920 Procedures for the Evaluation and Classification of Personal Armor" and NIJ Standard – 0101.06, indicate the method to statistically assess the resistance of personal ballistic protection materials. To be validated and accepted through these procedures, a personal ballistic protection material should withstand an impact of a specific projectile with a probability of a partial penetration confidence level higher than 90%. The present study introduces an energy equilibrium method to assess the confidence level for the probability of partial penetration of ductile and brittle materials. The experiments performed in the Ballistics laboratory of the Royal Military Academy in Belgium, use a modified pendulum method that allowed the quantification of the energy balance before and after the ballistic impact. The results were then compared with the ones obtained using the method specified by the NATO standard and NIJ 0101.06, mentioned above. The outcome of this comparison shows the tendency of the values obtained by the pendulum method to faithfully follow the values obtained according to NATO and NIJ specifications. The presented method is not based on statistical estimations, but instead, an exact method, of computing the energy absorbed by the tested material. This is an advantage for the cases when the material to be evaluated is expensive or it is in the development phase and mass production is not possible.

Graphene Nanoplatelets on Multi-Scale Polymer Composites for Potential Ballistic Shielding

Continuous development, improvement and innovation of ballistic material systems with superior energy absorption performance has been the subject of numerous works nowadays. Some research has been carried out with the objective of replacing traditional metallic and ceramic materials and composites with high-performance polymeric composites. Due to their excellent properties, multi-scale polymer composites have been used in the most varied segments of the industry, being recently researched in applications such as ballistic materials. This work promotes the combination of high-strength three-dimensional woven aramid fiber fabrics with vinyl ester resin to produce a panel through the compression molding process. The resin was reinforced with graphene nanoplatelets (0.1, 0.2 and 0.3% wt). The impact, tensile and flexural strength were evaluated, along with dynamic-mechanical analysis by DMA and by Hopkinson split bar test, indicating a trend of better performance for the composite containing 0.1% of graphene nanoplatelets.

Effect of thermally induced microstructural changes on the mechanical properties and ballistic performance of poly (p-phenylene terephthalamide) fibers

Microstructural variations have a strong influence on the load transfer capacity of the high-performance polymeric fibers, which is also reflected in their ballistic property changes. The focus of the present study is to investigate thermally induced microstructural changes and their reflection on the mechanical properties and theoretical ballistic limit of poly ( p-phenylene terephthalamide) fibers by a correlation. From the quantitative analysis of XRD, thermally induced changes in unit cell a-dimension show profound sensitivity in affecting the tenacity and modulus of the fibers. Based on the physicochemical changes in FTIR and FESEM analysis, significant surface deterioration and changes in the chemical network are observed. However, dimensional variations of the crystal structure along a-direction show a stronger influence than the chemical and morphological changes, reflecting sigmoidal responses with tenacity, modulus and theoretical V50 by correlations. As an effect of unit cell dimensional variation, changes in crystallinity are resulted and lead to the loss in theoretical ballistic limit of the fibers by following first-order kinetics. Lastly, angular separation and (200) orientation angle are determined to build a global correlation with modulus and theoretical ballistic limit for quickly decoding macro-changes in terms of micro-properties. The given correlations can help to identify crystallographic transformations upon other induction techniques and view their effect on mechanical and ballistic parameters. In addition, the given approach can be extended for different ballistic materials under any environmental conditions.

An Experimental Investigation into Mechanical and Thermal Properties of Hybrid Woven Rattan/Glass-Fiber-Reinforced Epoxy Composites.

The investigation of hybrid, woven, natural fiber-reinforced polymer composites as a substitute reinforcement for fiber polymer composites has recently caught the interest of academics, industry, and researchers. Woven, natural fiber composites have been implemented in many different applications, including parts for automobiles, household items, flooring, aerospace, and ballistic materials. Therefore, this research seeks to establish the thermal and mechanical characteristics of composites made from rattan strips (RS) and glass fiber (GF)-reinforced epoxy resin (ER). Other than that, the impact of layering configurations with respect to the thermal and mechanical characteristics of the RS and GF will be determined. Hand lay-up and a hydraulic press machine produce hybrid, woven RS and GF laminates. The hybrid composite's mechanical properties will be investigated using impact, tensile, and flexural tests. The hybrid woven of the GF/RS/RS/RS/GF composite sequence demonstrated the highest mechanical properties in comparison to other sequences. The increase from one to three layers of RS in the core layer of GF hybrid composites enhanced the flexural, impact, and tensile properties. In addition, the hybridization of rattan and GF is more thermally stable, as recorded by the high decomposition temperature. As a finding of the research, the woven RS and GF hybrid is a potential material for automotive applications such as car bumpers, for example.

Rock characteristics of post-caldera volcanoes in Dieng volcanic complex (DVC), Central Java, Indonesia

The Dieng volcanic complex (DVC) has one of the densest post-caldera volcanisms activity presents in Indonesia, yet its population density is considerably high. Therefore, it is important to identify the rock characteristics produced by the DVC post-caldera volcanoes to understand the risks and future hazards (i.e., eruption style). Based on lithology, we have classified DVC post-caldera volcanoes as (1) pyroclastic domain (PD; including Pagerkandang, Merdada, and Pangonan), and (2) lava domain (LD; including Prambanan, Kendil, Pakuwaja, Sikunir, Sikarim, and Seroja). PD is characterized by the domination of pyroclastic materials (mostly ash and lapilli) with oxidized scoria and volcanic lithics (fresh and/or altered) as the main components. The oxidized scoria clasts are moderately vesicular (27–41 % vesicularity; ) and phenocryst poor (<5 % phenocryst crystallinity, ), with plagioclase, pyroxene, and oxides as the main phenocryst phases. The LD is composed predominantly of lava. The observed lavas are typically dense (mostly <1 % , phenocryst rich (21–47 % ), and include plagioclase, pyroxene, biotite, amphibole, and oxides as the main phenocryst phases. Such differences in mineralogy and textures (i.e., vesicularity and crystallinity) suggest that PD and LD were likely sourced from different magmatic sources with different eruption styles (explosive and effusive styles, respectively). We have suggested that civilization settlements near PD are facing major threats from explosive magmatic, phreatomagmatic, and phreatic eruptions that could produce significant fallouts, ballistic materials, and highly destructive pyroclastic density currents. LDs pose a threat in the form of effusive magmatic eruptions such as lava flows and/or domes.

Numerical and Experimental Study of Multi-Layer Armors for Personal Protection

With continuous of the wars and the rise of the killings, taking place in the world it was necessary for us as engineers and researchers that we step even slightest to reduction in killings, and the current research is an attempt in this direction. Composite ballistic body armor materials have become a better body armor protection when contrasted with conventional steel body armor as far as its diminishment in weight and a perfection in ballistic resistance. The current research attempted to design and manufacture a novel body armor from cheap and available materials. In this study, alternative materials were proposed to develop an armor consisting of modified rubber and ebonite, as well as pieces of ceramic from alumina as hexagons shape, Kevlar and Carbon woven, and modern technologies shear thickening fluids. The armor was numerically evaluated using (ANSYS) commercial software using different bullet velocities ranging from (740 to 940) m/s and different numbers of carbon and Kevlar woven soaking shear thickening fluids to reach the best arrangement of layers with the best performance and compare them in the experimental data. The numerical results showed the best performance for plate armor consisting of 23-layers, which were then experimentally tested using a weapon type (AK-47) rifle with bullet 7.62*39 mm. The experimental test showed no complete penetration, with a back deformation of 7.5 mm. When the shock of the double bullet into the plate at the same location showed no complete penetration with a back deformation of 11.3 mm. The experimental data confirmed well with the numerical results and the body armor exhibited superior protective performance and was compatible with standard NIJ Standard-0101.03.