Projectile Impact Research Articles

Design, Manufacturing, and Analysis of Periodic Three-Dimensional Cellular Materials for Energy Absorption Applications: A Critical Review.

Cellular materials offer industries the ability to close gaps in the material selection design space with properties not otherwise achievable by bulk, monolithic counterparts. Their superior specific strength, stiffness, and energy absorption, as well as their multi-functionality, makes them desirable for a wide range of applications. The objective of this paper is to compile and present a review of the open literature focusing on the energy absorption of periodic three-dimensional cellular materials. The review begins with the methodical cataloging of qualitative and quantitative elements from 100 papers in the available literature and then provides readers with a thorough overview of the state of this research field, discussing areas such as parent material(s), manufacturing methods, cell topologies, cross-section shapes for truss topologies, analysis methods, loading types, and test strain rates. Based on these collected data, areas of great and limited research are identified and future avenues of interest are suggested for the continued maturation and growth of this field, such as the development of a consistent naming and classification system for topologies; the creation of test standards considering additive manufacturing processes; further investigation of non-uniform and non-cylindrical struts on the performance of truss lattices; and further investigation into the performance of lattice materials under the impact of non-flat surfaces and projectiles. Finally, the numerical energy absorption (by mass and by volume) data of 76 papers are presented across multiple property selection charts, highlighting various materials, manufacturing methods, and topology groups. While there are noticeable differences at certain densities, the graphs show that the categorical differences within those groups have large overlap in terms of energy absorption performance and can be referenced to identify areas for further investigation and to help in the preliminary design process by researchers and industry professionals alike.

Mechanical responses and damage characteristics of the high-velocity impact of ice projectiles on foam sandwich structure

The integration of composite sandwich structures in aircraft design necessitates consideration of hail impacts within aerospace applications. This investigates the dynamic response and damage characteristics of a carbon fibre/PMI foam sandwich structure under hail impact through both experimental and numerical simulation methods. These methods analyse the impact velocity, fibre panel thickness, and angle of incidence of the ice projectiles. The study establishes relationships among various parameters such as ice projectile impact force, foam absorption energy, and target plate deformation in relation to the impact velocity and angle of incidence. The damage sustained by the carbon fibre/PMI foam sandwich (CPS) structure due to ice projectile impact was systematically categorized and examined. Additionally, the effects of normal and tangential impact velocities on the target plate's dynamic response during oblique impacts were investigated. This research serves as a valuable reference for understanding the dynamic response and damage characteristics of composite foam sandwich structures subjected to ice projectile impacts, With a focus on the carbon fibre/PMI foam sandwich structure.

Damage characteristic of electronic devices caused by products generated by Al/Ep/KMnO4/TiH2 active material projectile hypervelocity impacting on aluminum target

As the space environment becomes more competitive, space offense and defense are increasing every day. Projectiles made of reactive materials can achieve highly effective target destruction due to their good penetration, ignition and detonation capabilities as the kill element in space attacks. When a spacecraft encounters a hypervelocity impact from a projectile of active material, it will have a serious impact on the surface material and internal electronics (logic chips, super-capacitors, etc.), leading to anomalies in the spacecraft's on-orbit operation. In order to study the damage characteristics of internal typical logic chips and super-capacitor modules caused by the hypervelocity impact of active material projectiles on the surface of spacecraft, the simulated satellite experiment of Al/Ep/KMnO4/TiH2 active material projectiles hypervelocity impacting on aluminum target was performed. By using the self-built experimental loading system, plasma characteristic parameter diagnosis system, radiation temperature measurement system and electronic device function detection system, the characteristic parameters of plasma, light flash radiation temperature, temperature evolution process of logic chip and super-capacitor at specific position under different impact velocities are obtained. When the damage behavior of Al/Ep/KMnO4/TiH2 active material projectile impacts on the surface of simulated satellite, the main reasons affecting electronic devices and the damage characteristics of impact products on logic chip and super-capacitor are analyzed. The experimental results show that the plasma is the main reason for interfering with the operation of logic chips and super-capacitors. When the active material projectile impacts the simulated satellite at the speed of 1.26 km/s, 1.67 km/s and 2.13 km/s, the charge and discharge time of the super-capacitor increases by 3.28 times, 4.57 times and 6 times, respectively, and the maximum operating voltage performance decreases by 12.23%, 14.44% and 18.15%, respectively. When the impact velocities are 1.67 km/s and 2.13 km/s, the output signal of the CD74HC00 chip appears transient damage due to the injection of the plasma generated by the impact, which last 0.4 ms and 1.8 ms, respectively.

Evaluating the performance of ceramic/fabric composite panels against simultaneous steel projectile impacts: An experimental and numerical study

In order to evaluate the ballistic performance of ceramic/fabric composite panels developed using 99.5 % alumina, Kevlar® and carbon fiber fabrics; a series of experiments were performed on the physical samples. The composite-projectile interaction was investigated in detail by means of finite element analysis using LS-DYNA®. The validated numerical model of the ceramic/fabric composite system was tactically modified to investigate the composite/projectile interaction for simultaneous projectile impacts at different impact velocities. The numerical model predicted the failure mechanism of the composite panel and the exit velocity of the projectile piercing through the composite accurately. This study reveals the important aspects of ballistic impact on composites under simultaneous multiple projectile impact condition which in turn, is a much more complex and critical case as compared to sequential multiple projectile impacts.

Analysis of bullet impact test on aluminum alloy plates at varying thickness and velocities

Analysis of bullet impact test on aluminum alloy plates at varying thickness and velocities

Failure pattern in ceramic metallic target under ballistic impact

The ballistic resistance and failure pattern of a bi-layer alumina 99.5% - aluminium alloy 1100-H12 target against steel 4340 ogival nosed projectile has been explored in the present experimental cum numerical study. In the experimental investigation, damage induced in the ceramic layer has been quantified in terms of number of cracks developed and failure zone dimensions. The resultant damage in the backing layer has been studied with variation in the bulge and perforation hole in the backing layer with the varying incidence velocity. The discussion of the experimental results has been further followed by three dimensional finite element computations using ABAQUS/Explicit finite code to investigate the behaviour of different types of bi-layer targets under multi-hit projectile impact. The JH-2 constitutive model has been used to reproduce the behaviour of alumina 99.5% and JC constitutive model has been used for steel 4340 and aluminium alloy 1100-H12. The total energy dissipation has been noted to be of lesser magnitude in case of sub-sequential impact in comparison to simultaneous impact of two projectiles. The distance between the impact points of two projectiles also effected the ballistic resistance of bi-layer target. The ballistic resistance of single tile ceramic front layer and four tile ceramic of equivalent area found to be dependent upon the boundary conditions provided to the target.

Study on Dynamic Mechanical Properties of Sandwich Beam with Stepwise Gradient Polymethacrylimide (PMI) Foam Core under Low-Velocity Impact.

Different PMI foam materials of 52, 110, and 200 kg/m3 were used to design stepwise gradient cores to improve the impact resistance of the sandwich beam. The stepwise gradient core consists of three layers arranged in positive gradient, negative gradient, and sandwich-core (e.g., 200/52/200). These sandwich beams were subjected to the impact of a steel projectile under impact momentum of 10 to 20 kg·m/s, corresponding to impact energy in the range of 12.5 to 50 J. During the test, the impact force was recorded by an accelerometer, and the different failure modes were also obtained. Subsequently, the influence of the layer arrangement on the energy absorption and load transfer mechanism between the different layers was analyzed. The results showed that the top layer with a large density can improve the impact force, but the middle/bottom layer with a low density promoted specific energy absorption. Thus, based on these two points, the negative gradient core (200/110/52) had an excellent specific energy absorption because it can transfer and expand the area to bear the load layer by layer, which improved the energy absorption in each layer. Combined with the failure modes, the load transfer and deformation mechanisms between the layers were also discussed. The present work provided a valuable method to design an efficient lightweight sandwich structure in the protection field.

Computational studies on hyper velocity impact of spherical projectiles on whipple shield with hybrid Newtonian fluid-filled core

Satellites orbiting in low Earth orbits face potential threats from space debris. To mitigate this risk, a Whipple shield is employed to shield satellites from potential hyper-velocity impacts caused by debris of varying sizes and speeds. Typically, these protective systems use spaced aluminum plates affixed to the satellite’s exterior. Ongoing advancements in this field include exploring alternative materials such as foam, cellular cores, and ceramics to replace aluminum in plate construction. This study introduces a hybrid configuration featuring a Newtonian fluid-filled, high-performance fiber-reinforced polymer core positioned between the aluminum alloy plates, aiming to enhance the Whipple shield’s overall shielding effectiveness. The analysis of hyper-velocity impacts was performed numerically using ANSYS Autodyn® computational software. Spherical projectiles made of stainless steel, ranging in diameter from 2 mm to 4 mm, were selected for direct collision simulations with the Whipple shield at velocities of 5 km/s, 7 km/s, and 9 km/s. The front and rear plates, each 1 mm thick, were constructed using AA6061-T6. The core, measuring 10 mm in thickness, incorporated multiple plies of Kevlar fiber-reinforced polymer (KFRP), with interplay spacing between successive KFRP plies filled with a Newtonian fluid (water). It was observed that spherical projectiles made of stainless steel with diameter ≥ 3 mm penetrated the rear plate of the whipple shield at the lower velocity of 5 km/s, with enhanced damage as the initial velocity of the projectile was increased from 5 km/s to 9 km/s. The debris cloud was found to scatter the fluid droplets, rupture the successive KFRP layers, with the initial kinetic energy playing a significant role in the severity of the damage.

Dynamic failure behavior of 7B52 laminated aluminum alloy subjected to deformable projectile impact

The ballistic response and failure mechanisms during the impact of a 304 steel-core projectile on a 7B52 laminated aluminum alloy plate were investigated. The impact resistance of the target plate was obtained through ballistic testing, and a detailed analysis of the fracture mechanism was conducted using microstructure characterization. Furthermore, an enhanced Gurson-Tvergaard-Needleman (GTN) model was employed to simulate the ballistic impact process, as well as the initiation and propagation of fractures. The results revealed significant deformation following the impact of the 304 steel-core projectile on the 7B52-T6 laminated plate. The target plate exhibited spalling failure, shear failure, and ductile hole expansion, with spalling failure being caused by intergranular fracture mechanisms. In the high stress triaxiality regions of the 7A62 alloy, intergranular cracks are prone to occur, and shear stress influences the expansion of the cracks. Fragments following layer cracking adhere to the 7A52 layer, thereby increasing the ballistic resistance surface area. The 7A52 layer on the rear side of the target plate effectively absorbed the projectile's energy through bending and stretching deformation, thereby offering enhanced protection. Furthermore, the spall resistance of the 7B52 laminated plate eliminate secondary damage caused by spall fragments.

Numerical and Experimental Analysis of the Influence of Projectile Impact Angle on Armour Plate Protection Capability

This research manuscript describes the process of degradation of an Armox 600 armour plate during the impact of a 5.56×45 mm SS109 projectile. The creation process of the numerical FEM model of the projectile is presented. The projectile impact angle is set between 15° and 90°, and this phenomenon is investigated via numerical and experimental approaches. The experiment is conducted under the same conditions as the numerical approach to validate the FEM model. The experiments are conducted using a high-speed camera. This research manuscript presents the influence of the projectile impact angle on the degradation of the armour plate and its protection capability for different angles. The results demonstrate the dependence of the transferred energy on the armour plate, speed of the particles after impact, and trace dimensions on the armour plate for different impact angles.

Dynamic response of clamped metallic thin-walled cylindrical shells under lateral shock loading

A combined experimental and numerical study was carried out to explore the dynamic response of Q235 thin-walled cylindrical shells under lateral shock loading. The machined Q235 specimens were clamped on both sides and subjected to centered lateral simulated shock loading via foam projectile impact tests, with their dynamic deformation evolution, mid-point deflections, and final deformation modes experimentally measured. The mid-point deflections of the impact side are all positive (the direction of deformation is the same as the impact direction) while those of the rear side all exhibit negative values (the direction of deformation is opposite to the impact direction). To further explore this phenomenon, the method of finite element (FE) was employed to simulate the foam projectile impact, with good agreement against experimental measurements achieved. Using the validated numerical model, the effects of impact velocity, length-to-diameter ratio, and thickness-to-diameter ratio on the dynamic response of the thin-walled cylindrical shell were further analyzed. The direction of both side deflections and deformation modes are significantly affected by the impact level and the shell geometries. For the rear side, within the given range of impact momentum and geometric parameters, the numerically predicted deflection varies from −1.775 mm to 2.45 mm. Thereupon, the coupling of indentation and bulge deformation patterns are indicated, and their corresponding contribution changes are considered the main mechanism for determining the final deformation of the thin-walled cylindrical shell's rear side.

Optimization of multi-layered composites against ballistic impact: A mesoscale approach

There has been an urgent need to develop and analyse multi-layered composite structures with varying material properties to withstand projectile impact. The proposed study focuses on the optimization of the multi-layer composite to achieve maximum resistance/energy dissipation. This study investigates the mechanical performance of the proposed multi-layered composite configuration under high strain rate loading through a computational approach. The proposed multi-layered structure incorporates layers of reinforced concrete, boulders, an elastomer layer, an ultra-high-performance concrete panel, and a layer of steel plate. A mesoscale-based approach has been developed for the layer comprising boulders and mortar. A total of six different configurations have been considered to arrive at the most efficient one against projectile impact. Optimization of the proposed configurations has been done by utilizing the concepts of specific energy absorption and shock impedance. Additionally, the fracture and damage characteristics of each configuration are also studied. Ductile hole enlargement in the sandy soil layer, fragmentation failure in the boulders, petaling failure in the steel plate, and spalling failure in the concrete layer have been observed. Based on the specific energy absorption and shock impedance approaches, the optimum laying sequence for the ballistic impact of each material is suggested.

Stress wave attenuation in ultra-high performance fibre-reinforced concrete during ballistic impact

Depending on material properties and boundary conditions, various waves propagate within the target, during an impact event. Stress wave attenuation during ballistic impact can be expressed in strain profiles regarding time and distance from the impact point. The design of a ballistic-resistant structure thus depends on the stress wave attenuation. This present study focused on stress wave attenuation under projectile impact in ultra-high performance fibre-reinforced concrete (UHPFRC). 3 mm strain gauges were found suitable for such measurements. Two different types (steel fibres) of UHPFRC (Single fibre (S2): 2 % of 6 mm steel fibre and Hybrid fibre combination (S0.5L1.5): 0.5 % of 6 mm + 1.5 % of 13 mm steel fibres) were used for investigation. During the ballistic impact event, strain profiles at specific distances from the point of impact on both the front and rear surfaces of UHPFRC targets were recorded. The scabbing damage due to tension was captured and analysed in this study through stress wave attenuation. The impact performance of hybrid (Short and Long fibres) S0.5L1.5 UHPFRC combinations was much better than S2 (only short fibres) UHPFRC targets. The hybrid steel fibre UHPFRC also shows higher strain attenuation (than short fibre based UHPFRC) in the range of 10-30 µε/mm. It was concluded that the efficiently designed ballistic-resistant UHPFRC should have higher wave attenuation, implying the concrete has enhanced capacity to absorb and localise energy, thereby mitigating the extent of damage inflicted upon the overall concrete slab.

High velocity steel spheres impact and damage analysis of graphene doped T700 composite shielding panels

Composite materials are increasingly being used in aircraft components such as fuselage panels which are subject to collision with debris during take-off/landing or in flight. This article provides an analysis of the impact resistance capability of graphene doped T700 (T700G) multilayer composite, when subjected to steel projectile impacts. Test coupons with 300×300 mm were impacted by steel spherical projectiles, with impact energies ranging from 34 J to 338 J, using a compressed air operated cannon. Test data, such as impact and absorbed energy were determined through impact and residual projectile velocity, acquired using ballistic chronograph and two high speed cameras. Damage assessment was performed using non-destructive techniques such as Ultrasonic testing before and after impact test. Through modelling and simulation, using ABAQUS/Explicit, and recording the change of projectile velocity, the energy loss of projectile is calculated, and the impact resistance is judged together with damage extent. T700G has similar impact resistance to AL2024, underperforming when impacted by larger projectiles and presenting an overall higher damaged area.

Study on projectile impact resistance of carbon-glass hybrid bioinspired helical composite laminate

Mantis shrimp dactyl clubs have excellent impact resistance due to their special helical structure. Meanwhile, hybrid fibre has become increasingly popular to improve the mechanical properties of composite materials. Based on the helical structure of the periodic region of mantis shrimp dactyl clubs and hybrid fibres, in this study, a hybrid fibre helical lay-up laminate (HHL) is designed. The laminates are prepared using unidirectional carbon fibre prepregs and unidirectional glass fibre prepregs. To study the protective performance and damage process of HHL, a light gas gun impact test and numerical simulation calculations were carried out on the specimens. The harvested protective capability of the HHL specimen was then compared with those of carbon fibre unidirectional lay-up laminate (CUL), carbon fibre helical lay-up laminate (CHL), and hybrid fibre unidirectional lay-up laminate (HUL) specimens. The ballistic protection capability of HHL at different helical lay-up angles was also explored. The testing results show that HHL has the best ballistic protection performance. HHL’s ballistic limiting velocity is 228.5 m/s, which is 49.5%, 30.8%, and 19.9% higher than those of CUL (152.8 m/s), CHL (174.7 m/s), and HUL (190.5 m/s), respectively. Finally, hybrid fibres with a 90° interlaminar helix angle were found to have the highest ballistic limiting velocity. The reason is that the larger interlaminar angle allowed more fibres to be involved in the protection, increasing the energy loss of the projectile and enhancing the protection of the laminate.

Penetration resistance of corrugated hybrid structures with ceramic insertions against steel projectile impact

Ceramic-metal corrugated structures have attracted extensive attention because of their strong penetration resistance. In this study, the effects of geometric features and boundary constraints on corrugated structures consisting of a TC4 frame and five SiC ceramic prisms were explored by performing a series of ballistic tests. Deformation results were obtained using a three-dimensional scanner, and the dynamic response was observed using a high-speed imaging system. Numerical models of these tests were established and validated using experimental results. The results suggest that increasing the support and confining strength of ceramics delay their failure and increase their degree of breakage, thereby increasing the internal energy conversion ratio of the projectile and the energy absorption ratio of ceramics by 14% and 10%, respectively. Notably, a reasonable reduction in the strength of the frame partition expands the plastic deformation range of the frame and increases its energy absorption ratio by 10%. The conclusions of this study provide a reference for designing corrugated composite structures.

Numerical Study of the High-Speed Impact of a Steel Projectile on a Concrete Target

Numerical Study of the High-Speed Impact of a Steel Projectile on a Concrete Target

Research on the high-speed impact of projectiles on reinforced concrete equivalent targets

Due to the prolonged production cycle of reinforced concrete target plates and the need for a series of preparations and tests before use, it is essential to study the equivalent relationship between reinforced concrete target plates and steel target plates. Numerical simulations of the process of projectiles vertically penetrating reinforced concrete target plates were conducted using LS-DYNA software. Models for both reinforced concrete and steel targets were established, and the equivalent thickness conversion relationship between the two was obtained. Simulation results indicated an inverse proportional relationship between projectile residual kinetic energy and target thickness. Curve fitting using Origin software was performed to obtain the conversion relationship between the thicknesses of reinforced concrete target plates and steel targets. The simulation results were validated, showing an error in concrete target plate thickness conversion of less than 10%. The research results provide theoretical support and data references for the equivalent study of reinforced concrete target plates and steel target plates.

Experimental and numerical study on projectile impact damage of EBC-SiC/SiC

The ingested particles or debris will cause high-speed & low-energy impact to the hot end components of aeroengine. Few literature focus on the projectile impact of SiC/SiC with Environmental Barrier Coating(EBC). The impact of 2 mm projectile was specially studied for Si/Yb2Si2O7/Yb2SiO5-SiC/SiC. Gas gun system was used to conduct impact testing at the speed of 3 m/s∼353m/s. The optical microscope, Scanning Electronic Microscope(SEM), micro CT were used to observe the impact and tension after impact(TAI) damage. For TAI, Digital Image Correlation (DIC) was used to conduct the full-field strain detection around the impact point. Meanwhile, the Smoothed Particle Hydrodynamics (SPH) methodology was programmed in C++ and developed to simulate SiC/SiC impact problem by introducing modified Hashin-Rotem criteria, extending interface method to 3D and adding GPU accelerated algorithm. The results indicate that threshold velocities of EBC huge peeling and SiC/SiC penetration are different, TAI residual strength also has extinct threshold at the velocity of 246 m/s with 37.1% declining extent, and the impact pit depth of SPH simulation is in good agreement with the experiment.

Identification and quantification of projectile impact marks on bone: new experimental insights using osseous points

Shifts in projectile technology potentially document human evolutionary milestones, such as adaptations for different environments and settlement dynamics. A relatively direct proxy for projectile technology is projectile impact marks (PIM) on archaeological bones. Increasing awareness and publication of experimental data sets have recently led to more identifications of PIM in various contexts, but diagnosing PIM from other types of bone-surface modifications, quantifying them, and inferring point size and material from the bone lesions need more substantiation. Here, we focus on PIM created by osseous projectiles, asking whether these could be effectively identified and separated from lithic-tipped weapons. We further discuss the basic question raised by recent PIM research in zooarchaeology: why PIM evidence is so rare in archaeofaunal assemblages (compared to other human-induced marks), even when they are explicitly sought. We present the experimental results of shooting two ungulate carcasses with bone and antler points, replicating those used in the early Upper Paleolithic of western Eurasia. Half of our hits resulted in PIM, confirming that this modification may have been originally abundant. However, we found that the probability of a skeletal element to be modified with PIM negatively correlates with its preservation potential, and that much of the produced bone damage would not be identifiable in a typical Paleolithic faunal assemblage. This quantification problem still leaves room for an insightful qualitative study of PIM. We complement previous research in presenting several diagnostic marks that retain preservation potential and may be used to suggest osseous, rather than lithic, projectile technology.