Ballistic Resistance Research Articles

Experimental and Numerical Study on the Ballistic Resistance of Heterogeneous Double-Layered Aluminum Alloy Targets Against Blunt Projectiles

Experimental and Numerical Study on the Ballistic Resistance of Heterogeneous Double-Layered Aluminum Alloy Targets Against Blunt Projectiles

Numerical Analysis of SiC and UHMWPE Composite Ballistic Plates against 0.5 Caliber BMG Projectile

The aim of this study was to determine the optimal configuration of silicon carbide-ultrahigh molecular weight polyethylene (SiC-UHMWPE) plates to effectively withstand 0.5 caliber Browning Machine Gun (BMG) projectiles. Six composite plates with varying thicknesses were 3D modeled and assessed for ballistic resistance using finite element analysis in Ansys Explicit Dynamics simulation software. These plates were subjected to high-velocity impacts at 930 m/s using 7.62 mm projectiles. The findings revealed that an 11 mm SiC/80 mm UHMWPE plate provided comparable bullet-stopping performance to a standard 8 mm steel 4340/60 mm UHMWPE plate, but with a significantly lower areal density. The primary mode of failure observed in penetrated samples was petaling, consistent with known behaviors of composite armor under high-impact conditions.

Numerical Study of Ballistic Performance in Level III SiC Ceramic Multilayered UHMWPE Ballistic Plates

This study investigates the ballistic resistance of composite plates composed of a silicon carbide (SiC) strike face and ultra-high molecular weight polyethylene (UHMWPE) layers against 7.62 mm NATO caliber projectiles using Ansys Explicit Dynamics. Five ballistic plate samples were numerically modeled, featuring 40 to 60 UHMWPE layers and a 4 mm SiC strike face. The simulation assessed the plates' response, including backface signature, bullet penetration depth, absorbed kinetic energy, and deformation mechanisms. The findings revealed that increasing the UHMWPE thickness reduces both the backface signature and bullet penetration depth. Plates with 50 to 60 layers of UHMWPE met level III NIJ standards, demonstrating lower backface signatures and bullet penetration compared to those with 40 or 45 layers. Thicker UHMWPE layers were associated with reduced deformation, with the plate featuring 60 layers of UHMWPE and an overall thickness of 25 mm emerging as the optimal configuration for level III ballistic protection.

Experimental and numerical study on CuO/ZnO-modified aramid fabric for ballistic and UV radiation protection

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

Ballistic resistance of ceramic and metal target plates impacted against different projectile’s nose shape: A numerical investigation

Layered ceramic/metal plates are investigated for ballistic impact against projectiles with different nose shapes. Explicit finite element method is used to model the target and projectile. This study examines the effect of nose shapes on the ballistic performance of target. This includes replacing the metallic layer with a ceramic plate of the same thickness to identify the best ceramic-to-target plate ratio for maximum BLV. Ballistic performance is compared between two different configurations having equal total thickness of ceramic and metallic layer. Increased ceramic layer thickness upto certain thickness-ratio may significantly improve the target plate’s ballistic resistance for all bullet types.

Biomimetic 3D-printed Composites: Ballistic Impact Resistance with Nacre-Inspired and Tubulane Structures

This research delves into nature-inspired designs for creating materials with exceptional impact resistance, leveraging cutting-edge 3D printing techniques. Our composite design features a nacre-like outer layer combined with a tubulane-resembling core, aiming to enhance energy dissipation significantly. By emulating the dense aragonite structure found in natural nacre and the unique porosity of tubulane, to enhance ballistic impact resistance. To validate its effectiveness, we conducted ballistics tests using a 40-grain lead-tipped .22 LR bullet at an initial velocity of 330.7 m/s, with a specialized chronograph setup to measure both initial and post-penetration bullet velocities, quantifying energy absorption precisely. This study opens new frontiers in aviation safety, structural engineering, and personal protective equipment, showcasing the transformative potential of biomimicry and additive manufacturing in advancing public safety and material science.

Penetration resistance of Al2O3 ceramic-ultra-high molecular weight polyethylene (UHMWPE) composite armor: Experimental and numerical investigations

To enhance the protective performance of ceramic composite armor, ballistic penetration experiments were conducted on Al2O3 ceramic-ultra-high molecular weight polyethylene (UHMWPE) composite armor with different thickness configurations. The damage and failure modes of hard projectiles and ceramic-fiber composite targets were analyzed. The recovered projectiles and ceramic fragments were sieved and weighed at multiple stages, revealing a positive correlation between the degree of fragmentation of the projectiles and ceramics and the overall ballistic resistance of the composite targets. Numerical simulations were performed using the LS-DYNA finite element software, and the simulation results showed high consistency with the experimental results, confirming the validity of the material parameters. The results indicate that the projectile heads primarily exhibited crushing and abrasive fragmentation. Larger projectile fragments mainly resulted from tensile and shear stress-induced failure. The failure modes of the composite targets included the formation of ceramic cones and radial cracks under high-velocity impacts. The UHMWPE laminated plates exhibited interlayer separation caused by tensile waves, permanent plastic deformation of the rear surface bulging, and perforation failure primarily due to shear forces.Through extended numerical simulations, while maintaining the same areal density and configuration of 9 mm Al2O3 ceramic + 12 mm UHMWPE laminated composite armor, the thickness configurations of the Al2O3 ceramic and UHMWPE laminated backplates were varied, and various thicknesses of UHMWPE laminates were simulated as the cover layer for the ceramic panels. The simulation results indicated that the composite armor configuration of 10 mm Al2O3 ceramic + 8 mm UHMWPE composite armor increased energy absorption by 13.48 %. When altering the cover layer thickness, a 4 mm UHMWPE + 9 mm Al2O3 + 8 mm UHMWPE composite armor demonstrated a 27.11 % improvement in energy absorption, showing a relatively significant enhancement.

An experimental and numerical investigation of ballistic penetration behaviors of deployable composite shells

Bistable composite shells are suitable candidates for deployable space structures due to high stiffness to weight ratio as well as large volume reduction. Nevertheless, impact performance of bistable composite shells conflicting with space debris have been rarely studied. In this paper deployable hybrid composites constructed with combinations of carbon–carbon, carbon–kevlar, kevlar–kevlar, high-energy-absorption graphene-reinforced polyurethane elastomers are developed, and their ballistic penetration behaviors are experimentally and computationally studied. The influences of ballistic velocity on the absorbed energy, the residual velocity and damage morphology of the targets are investigated in both deployed and coiled stable states. The results show that severe local damages were observed for the carbon–carbon and carbon–kevlar samples after penetration with various velocities even first cosmic velocity, and the sample of deployable hybrid composite shell yielded the best ballistic impact resistance. The total energy absorption performance of the hybrid composite structure was greatly improved by introducing graphene-reinforced polyurethane elastomers without losing the deployability. Additionally, investigation on the energy absorption capability of deployed laminated shells with various curvature radii indicated that the curvature radius had a significant effect on the anti-penetration performance.

Enhancing concrete’s ballistic impact resistance using Alfa fiber

Natural fibers are gaining interest in recent years due to the increasing calls for eco-friendly materials production. Concrete reinforcement with Alfa fiber is attracting attention to take benefit of natural fiber advantages in the construction sector. The mechanical and physical characteristics of concrete reinforced with Alfa fibers have been primarily investigated. The current study seeks to analyse the ballistic protection performance of Alfa-reinforced concrete in response to the emerging need to withstand bullet impacts and protect occupants in light of the increasing armed hostilities. Eight formulations were selected for the concrete preparation by varying the Alfa fiber content from 0 to 100 kg/m³. After determining the mechanical characteristics of the concrete such as compressive, flexural and tensile strength, ballistic resistance to bullet impacts is determined by measuring the penetration depth, the crater area and the lost mass after impact in concrete slab 10 and 15 cm thick. The formulations of Alfa-reinforced concrete exhibited lower penetration depth, crater area, and lost mass compared to the reference concrete. Optimal values were achieved with 15 kg/m³ of fibers. A dependency between the ballistic response on the fibrous concrete and flexural strength of concrete is also remarked. In conclusion, the study demonstrates that incorporating Alfa fibers into concrete significantly enhances its ballistic resistance, with optimum performance observed at 15 kg/m³ of fiber inclusion. These findings underscore the potential of Alfa-reinforced concrete for use in military constructions and structures vulnerable to impact risks, paving the way for further research and practical applications in enhancing structural and occupant safety.

Predicting ballistic resistance based on the mechanical properties of armored ceramics

The relationship between the mechanical and ballistic properties of armored ceramics was studied using a numerical method that combines finite element simulation and machine learning. A dataset containing the physical properties, mechanical properties, and ballistic performance of ceramic was built through numerical simulation with the JH-2 model. The machine learning method was employed to establish a relationship between residual penetration depth and ceramic’ properties, including its density, elastic modulus, Poisson's ratio, Hugoniot elastic limit (HEL), dynamic compressive strength, quasi-static compressive strength, and bending strength. Through finite element simulation and machine learning, univariate analysis of the physico-mechanical properties of ceramics was achieved by predictive modeling. It was found that density, dynamic compressive strength, quasi-static compressive strength, and HEL had the most significant impact on the residual penetration depth, making them the key controlling parameters for the ballistic performance of ceramics. By combining the prediction results of the machine learning model with the influence patterns of the parameters, a predictive formula for the ceramic protection coefficient based on the key parameters was established.

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 thermoviscoplastic material models in predicting the thermomechanical behavior of rolled homogenous armor steel

This paper studies the dynamic and elevated temperature behavior of rolled homogeneous armor steel, which is crucial for applications such as blast, impact, crash, and ballistic resistance. The deformation behavior is analyzed through tensile tests. The tensile tests of RHA steel are conducted at quasi-static 10−4s−1≤εṗ≤10−1s−1 to dynamic 10−1s−1≤εṗ≤36.439s−1 strain-rates and at high temperatures ranging from room temperature (RT,27°C) to 500°C. Phenomenological Johnson-Cook (JC) models and semi-physical Rusinek-Klepaczko (RK) material models are employed in finite element (FE) simulations of tensile tests. The JC failure model, with a small modification, is used along with the material models to simulate the loss of load-bearing capacity of the component. All necessary material parameters are extracted from the test data. The material models and the damage model are integrated into ABAQUS CAE FE software through a user-defined material subroutine (UMAT). The simulated outcomes acquired from diverse material models are validated with relevant experimental findings, and the effectiveness of each material model is evaluated through qualitative and quantitative assessments. Observations reveal limitations in the existing models to accurately replicate material behavior under tension, particularly in the dynamic strain rate, and elevated temperature range. Consequently, a modified version of the JC model (MJC) is explored to better account for the impact of temperature on strain hardening and strain rate hardening. The proposed modification in the material model significantly enhances the predictive accuracy of FE simulations of tensile deformation across the entire spectrum of studied strain rates and temperatures compared to the original JC and RK models.

Dynamic response of UHMWPE/polyurea composite plates under combined blast and ballistic impact

Combined load caused by blast impulse and fragmentation impact poses a synergetic damage threat to the protective structure. To improve the blast and ballistic impact resistance of Ultra-high molecular weight polyethylene (UHMWPE), polyurea coated Ultra-high molecular weight polyethylene structure was proposed, and the composite structures with different coating thickness and coating position were prepared. Composite projectiles formed by combining foam projectiles and steel projectiles were launched by light gas gun to simulate the combined load of explosion impact and fragmentation. Comparative experimental studies were carried out. The experimental results show that the polyurea layer has good elastic properties, preventing the excessive deformation of the PE layer. The polyurea coating position and the time interval of the combined load show significant influence on the impact resistance of the composite structure. When the load was relatively low, PE plate with polyurea coating on booth face has both the advantages of PE plate with coating on the front and back face, but when the load increased, the impact resistance potential of polyurea layer was not fully developed. With the increase of the combined load, structures with polyurea coating on the back face has a good resistance of combined impact.

Mechanical and ballistic studies of boron carbide filler reinforced glass fiber composites

AbstractOwing to the outstanding properties of boron carbide (B4C) particles, material researchers have shown potential in filler‐reinforced polymer composites. The present work studied the implication of B4C fillers on the mechanical and ballistic properties of glass fiber epoxy reinforced composites. Two different weight percentages of 2 and 4 wt% B4C fillers were used to modify the epoxy resin. The composite samples with glass fabric woven were made through compression molding. The results show that the tensile, flexural, interlaminar, impact strength and hardness of glass fiber composite were improved by addition of 2 wt% of B4C. The high‐velocity ballistic tests were conducted on the unfilled and B4C filler‐reinforced composites using a 9 mm parabellum projectile with an initial striking of 372 ± 15 m/s. The least back face signature (BFS) and highest specific energy absorption (SEA) were observed for 2 wt% B4C filler composite. Adding B4C filler enhanced matrix toughening and interfacial bonding between fiber and matrix. Matrix cracking and fiber breakage result in the least ballistic resistance for unfilled composite. Fracture behavior was studied on tensile, impact, and ballistic‐tested samples using scanning electron microscopy. The fractured surfaces of filler‐reinforced composite demonstrated good interfacial bonding, matrix hardening, and fiber pullouts.Highlights The addition of B4C with epoxy up to 2 wt% improves the mechanical and ballistic properties of the composites. The least back face signature and highest specific energy absorption were observed for 2 wt% B4C filler composite. B4C filler enhanced matrix toughening and interfacial bonding between fiber and matrix. Failure of unfilled glass fiber composites is a combination of matrix cracking, fiber pullout, and interface debonding.

Determination of ballistic resistance model of finite thickness material based on Artificial Neural Network

Ballistic resistance behavior of finite thickness material is affected by factors of target thickness, projectile nose shape, and impact angle. The widely used ballistic limit velocity (BLV) model can only reflect the ballistic resistance behavior of a target in a single given impact scenario. The collected BLV from different impact scenarios can only partially reflect the effect of those factors on the ballistic resistance. A general model of BLV considering these factors simultaneously is desired.In this study, numerical impact models are first verified by a significant number of experiments. A guided random sampling method is proposed to collect numerical BLV data for training/validating usage. BLV data from experiments and simulations are then assembled by this method and subsequently trained by Artificial Neural Network (ANN). k-Folder Cross Validation (K-CV) technique designed for evaluating small sample training network is introduced to validate and test the network. The ANN-predicted results are decomposed by proper singular value decomposition methods. It is found that the Rank-1 decomposition results (with highest singular value) can fully reveal the decoupled relationship between BLV and its independent factors (MAPE < 6 %), with which analytical ballistic models are established. The results show that our proposed model can quantitatively describe the fully decoupled effect of target thickness, impact angle and projectile nose shape on the BLV with high accuracy.

Enhanced ballistic resistance of SiC ceramic-fiber composite armor: an investigation of fiber laminate backing effects and fragmentation dynamics

Enhanced ballistic resistance of SiC ceramic-fiber composite armor: an investigation of fiber laminate backing effects and fragmentation dynamics

Energy absorption and impact response of ballistic resistance laminate

Abstract High-speed impact performance has significantly expanded over the past few decades. The target response based on the impact conditions has been more difficult to visualise and evaluate. In this article, Ansys model analysis has been used to measure, visualise, and predict the projectile and target responses of Kevlar® (K) and Ramie® textile-reinforced unsaturated polyester resin (UP) matrix. The laminate thickness threshold was detected experimentally based on the highest stress intensity factor and energy release rates. Furthermore, tensile strength and bending of the laminate were found. The impact conditions have a significant impact on the target response; thus, an explicit dynamic analysis was used to visualise the impact response based on the number of target fixed supports (FSs). Two FS (2 FS) target absorbs 11% more energy than four FS (4 FS) target. Additionally, the target size has a major effect on the projectile and laminate responses, and a successful arrest of the projectile was detected in both cases. The smallest targets with 2 FS have the highest and wider response, where a successful change in the projectile trajectory was obtained.

Numerical simulation of composite materials with sisal and glass fibers for ballistic impact resistance

Numerical simulation of composite materials with sisal and glass fibers for ballistic impact resistance

Experimental and theoretical study of cone angle in alumina tiles under ballistic impact

The ceramic cone formed within the ceramic tiles provides effective ballistic resistance. Although the critical velocity of ceramic cone formation has been extensively studied, the cone angle in ceramic tiles after crack initiation is still unclear, which is important for understanding the anti-penetration process. In this paper, the cone angle in ceramic tiles is systematically investigated both experimentally and theoretically. First, the dynamic failure process of ceramic tiles is characterized by means of ballistic impact experiments, and the results show that the cone angle gradually decreases with the increase of the thickness of the ceramic tile, while it is independent of the impact velocity. Then, based on the minimization of deformation energy and fracture energy, a theoretical model is established for the first time to predict the cone angle, which takes into account the strain rate effect on tensile strength. This model can well explain the effect of the thickness, impact velocity and fracture properties of the ceramic material on the cone angle obtained in experiments. Increasing the thickness of the ceramic tiles results in larger ceramic fragments while the generated fracture energy declines. This leads to a decrease in the cone angle. Moreover, an increase in the fracture toughness or tensile strength of the ceramic material enhances the resistance to crack propagation, and the generated fracture energy decrease, resulting in a decrease in the cone angle. However, the cone angle does not change much with impact velocity because the impact velocity does not change the stress field distribution of the ceramic tile. This study is meaningful for understanding the ballistic resistance of ceramic tiles.

Design, Fabrication and Performance Test of an Effective Body Armor

Aims: This original research paper targets an easy but efficient design and fabrication of a safe body armor. A test bed with weapons was another key aim. Therefore, it is essential to verify the vest’s capability to withstand rigorous stab tests as prescribed by the standard. Background: The most widely used armor piece is the torso-protecting overt (worn over the uniform or clothing) one. The main concern of this work was to design and develop such a stabresistant soft body armor made from readily available materials to protect against threats such as knives, blades, and sharp-tipped objects. Objectives: From the Mechanical Engineering point of view, the present research goals for such an armor vest were: low cost, moderately lightweight, comfortable, made from easily available materials, simple forward design, easy to fabricate, and the ability to adjust the level of protection without altering the primary design structure. The effectiveness of the vest needed to be verified through rigorous testing following relevant standards. Methods: The prototype of the stab-resistant armor was fabricated with two different configurations and their performance was rigorously tested in accordance with the NIJ Standard-0115.00 to determine its level of protection. Nylon-based panel elements covered with rubber and cotton-based panels were compared in terms of their ability to stop stab threats. Taking into account the key point of strike energy levels during the stabbing, test beds were created in the laboratory to rigorously conduct the required tests. Blades of two types were made, attached with fixtures, and dropped on the armors (upon backing material) in the test bed. Results: The ‘Complete Armor’ showed excellent performance against stab attacks. The tests revealed that the nylon-based panel elements covered with rubber were more successful in stopping stab threats compared to cotton-based panels. Conclusion: The designed and fabricated prototype of the stab-resistant soft body armor achieved the desired level of protection against stab threats. The armor is also cost-effective, it can be fabricated using locally available materials, at a cost of only 10 USD compared to 300 USD for commercially available armor. Other: However, it should be noted that stab resistance does not necessarily imply ballistic resistance, and no armor can provide invincibility against all types of threats.