Low-velocity Impact Response Research Articles

Recent advances in the AlSi10Mg materials fabrication by selective laser melting: process parameters, optimization, low-velocity and ballistic impact responses

Recent advances in the AlSi10Mg materials fabrication by selective laser melting: process parameters, optimization, low-velocity and ballistic impact responses

Numerical simulation of low-velocity impact response of functionally graded SiCp/Al6061 composite plate using mesoscopic modeling and considering porosity

Numerical simulation of low-velocity impact response of functionally graded SiC_p/Al6061 composite plate using mesoscopic modeling and considering porosity

Low-Velocity Impact Behaviour of Titanium-Based Carbon-Fibre/Epoxy Laminate.

This study investigated the low-velocity impact response of titanium-based carbon-fibre/epoxy laminate (TI-CF FML). A comprehensive experimental study was carried out with impact energies ranging from 16.9 J to 91.9 J. Finite element analysis, performed using ABAQUS, was employed to elucidate the failure mechanisms of the laminate. Three distinct damage modes were identified based on the impact energy levels. The energy absorption characteristics of the TI-CF FML were analysed, revealing that maximum energy absorption is achieved and remains constant after penetration occurs. The relationship between impact force and displacement was also explored, showing that the laminate can withstand a peak force of 13.1 kN. The research on the impact resistance, damage mechanisms and energy absorption capacity of TI-CF FML provides an in-depth understanding of the impact behaviour of the laminate and its suitability for various industrial applications.

Prediction of low-velocity impact responses for bio-inspired helicoidal laminates based on machine learning

The inherent capacity of natural protective systems to withstand impact loadings, attributed to their microscale helicoidal architectures, has garnered significant interest. Drawing inspiration from this mechanically robust design, this study aims to introduce the composite laminates with a helicoidal distribution and to accurately and efficiently predict their Low-Velocity Impact (LVI) responses. Initially, the Latin hypercube design (LHS) was employed to generate 500 samples representing various pitch angles. An experimentally verified finite element model was then established to capture the load-displacement curves and energy-time curves for these 500 samples. Subsequently, the Convolutional Neural Network (CNN) model was utilized to accurately predict the load-displacement curves and energy-time curves for bio-inspired helicoidal laminates across different pitch angles. The principal component analysis (PCA) was used to enhance the efficiency of learning the load-displacement and energy-time curves in a reduced dimensional space, and the SHapley Additive exPlanations (SHAP) method was employed to investigate the feature importance of pitch angle. Finally, the helicoidal laminate with the highest energy absorption for a given volume was obtained by the genetic algorithm (GA) combined with the CNN model. This optimized laminate demonstrates a remarkable 9.5 % improvement in energy absorption compared to the best-performing sample within the original data set. Furthermore, the "spiraling" delamination damage of the helicoidal laminates was studied, which indicates that the delamination with small pitch angle is more pronounced for that with large pitch angle. The proposed method offers significant advantages in terms of cost reduction and efficiency enhancement for predicting the LVI responses of helicoidal laminates, holding immense potential in structural design and optimization of composite materials.

Smeared fixed crack model for quasi-static and dynamic biaxial flexural response analysis of aluminosilicate glass plates

Glass materials are extensively used in load-bearing structures and impact-resistant components because of their distinctive physical and chemical properties. Accurate predictions and assessment of the mechanical responses of glass structures are crucial for structural design and reliability analysis. In this study, quasi-static and dynamic ball-on-ring (BOR) biaxial flexural tests are conducted on aluminosilicate glass. The smeared fixed crack model is calibrated for deformation and failure analyses. First, the model parameters are calibrated carefully, particularly for different failure criteria. Both the deformation field and fracture modes agree well with the experimental observations during the quasi-static tests. For the low-velocity impact biaxial flexural loading condition, three different numerical techniques, namely the initial scaling tensile strength criterion, non-local approach with energy criterion, and rate-dependent failure stress criterion, are implemented in the numerical models for dynamic failure analysis. Finally, the proposed smeared fixed crack model is compared with the widely used Johnson Holmquist Ⅱ (JH-2) model and demonstrates advantages for low-velocity impact response analysis of glass structures.

Low-velocity impact behavior analysis on composite double curved-shell reinforced with graphene platelet

ABSTRACT This research investigates the low-velocity impact behavior of a spherical rigid body on a composite shell reinforced with graphene platelets (GPLs), in which GPL have been uniformly dispersed and randomly arranged within each individual layer. The weight proportion of GPL has been altered across the thickness. The modified Halpin Tsai model is employed to analyze the Young's modulus and the effective material characteristics of a composite reinforced with graphene platelets (GPLRC). The mass density and Poisson's ratio of the viscoelastic multilayer composite are determined using the rule of mixture. The material parameters of each layer are defined according to the Kelvin–Voigt model. The governing equations have been derived by applying the first order shear deformation shell theory, Hamilton's principle, and modifying the Hertz contact law. The PDE problems have been transformed into ODE equations through the utilization of the Galerkin method. Subsequently, the ordinary equations have been solved utilizing the Newmark method. A parametric study is conducted to examine the effects of various factors, such as fraction weight, GPL distribution pattern, impactor mass, radius, viscoelastic modulus, and initial velocity, on the low velocity impact response of a composite shell reinforced with GPL.

Low-velocity impact response of hybrid sheet moulding compound composite laminates

This work presents a comprehensive study on the impact damage tolerance of Sheet Moulding Compounds (SMCs). The performance of glass, carbon and hybrid glass/carbon SMCs are compared by means of tensile, compression, low-velocity impact and compression after impact experiments. Damage analysis of the impacted laminates was performed by ultrasonic and X-ray methodologies. The glass SMC exhibited the highest damage tolerance in low-velocity impact with the smallest damaged area, crack density and loss in compression after impact (CAI) strength. On the other hand, the carbon SMC demonstrated superior in-plane stiffness and strength, but exhibited a large damaged area and crack density under impact. The hybrid SMC displayed an optimal compromise, exhibiting intermediate tensile in-plane performance and excellent damage tolerance at lower impact energy levels, but suffered from extensive delamination at the highest impact energy. Overall, the findings highlight the suitability of hybrid SMCs for structural applications with potential impact risks.

Low-velocity impact response and damage mechanism of cosine function cell-based lattice core sandwich panels

This study aims to investigate the impact response and damage mechanism of cosine-function cell-based (CFCB) lattice core sandwich panels. Several low-velocity impact tests were conducted to explore their advantages in impact resistance by comparing them with traditional body-centered cubic (BCC) lattice-core sandwich panels. The impact response and deformation patterns of CFCB lattice core sandwich panels with two different faceplate materials (aluminum alloy and carbon fiber reinforced plastic composite) were experimentally investigated. The CFCB lattice core sandwich panels exhibited higher impact resistance and energy absorption capacity than their BCC lattice core counterparts. Furthermore, sandwich panels with aluminum alloy faceplates provided better impact resistance capacity than those with CFRP faceplates. Subsequently, several numerical models were developed to explore the deformation mechanisms and energy absorption characteristics of CFCB lattice core sandwich panels. In addition, the effects of the core structural parameters on mechanical performance were numerically investigated. Results indicated that increasing the cell rod diameter and/or reducing the cosine period length could decrease the indentation depth and enhance crush force efficiency. Finally, based on the principle of minimum potential energy, a theoretical model was developed to predict the initial peak load of CFCB lattice core sandwich panels with isotropic faceplates. This study aimed to explore the impact response and provide design guidance for CFCB lattice core sandwich panels.

Study on low-velocity impact response and residual strength of ultralight all-CFRP sandwich structure

The all-CFRP sandwich structure with ultralight honeycomb is designed and manufactured by stretching process. Two scenarios, including global and local impact, are considered to reveal the characteristics of impact resistance. The effects of different impact energies and core densities on energy absorption and failure mechanism are thoroughly discussed. Meanwhile, the post-impact residual compressive strength is carried out to evaluate the influence of impact on structural strength and stability. The results show that under the global impact, the impact resistance is related to core density, and the energy absorption is mainly from honeycomb core. While under the local impact, as the impact energy increases, the failure mechanism of the structure changes from core crushing to penetration. The research provides a guidance for low-velocity impact performance and structural optimization design of sandwich structures.

Low-velocity impact response of sandwich plates with corrugation star-shaped honeycomb hybrid core

Compared with traditional lightweight corrugation and honeycomb cores, the novel cellular structure exhibiting a negative Poisson's ratio possesses distinctive mechanical deformation features, making it suitable for modeling lightweight sandwich structures. Therefore, the concept of combining the auxetic honeycomb core with folded corrugations is proposed to construct a new type of corrugation star-shaped honeycomb (SSH) hybrid core for studying the dynamic behavior of sandwich panels subjected to low-velocity impact. Integrate Hertz elasticity theory and first-order shear deformation theory (FSDT) to develop an equivalent analytical model, and derive the equations of motion through Hamilton principle. To model contact force interactions during dynamic processes, a spring-mass model is utilized. Analytical solutions are derived for predicting transverse displacement with Duhamel's principle and Navier's method. Numerical simulations are conducted using the Abaqus commercial software, and the validity of the results is confirmed by comparing them with findings in the existing literature. Based on this, effective strategies for enhancing the sandwich panel's resistance to low-velocity impacts are proposed by examining the influence of different side length ratios, thickness ratios, and cell concave angles. In comparison to the corrugation re-entrant hexagonal honeycomb hybrid core sandwich panel structure, the corrugation SSH hybrid core sandwich panel structure reduces transverse displacement by 33.6 % at the same impact velocity.

Rebound characteristics of flexible and stiff jute rubber/epoxy hybrid composite under low-velocity impact

This present work aims to assess the low-velocity impact response of novel configuration based on jute/rubber/epoxy flexible and stiff composites having varying layup sequences using an experimental study. The Charpy and drop weight impact tests are done according to the standards. Drop weight low-velocity impact test at an energy level of 15J was performed using a conical shape impactor. Carboxylated Nitrile Butadiene Rubber (XNBR) containing carbon fillers ( N330 and N550) consisting 35 phr concentration each is used in the stacking sequence of the composite due to its high toughness and energy dissipation property. During drop weight tests conducted at a 15J energy level, the flexible RJRJR composite exhibited a peak force of 486 N, whereas the stiffer RJEJR composite demonstrated a peak force of 1075 N. The flexible composite shows no damage for the energy level tested. However, the stiff composite made using epoxy in between jute layers fails due to the matrix cracking in the composite. The peak force and specific energy absorption is dependent on stacking configuration and increases with the addition of rubber interface in the stiff composite. The energy absorption of stiff composite is higher as compared to flexible composite as indicated by the peak force.

Simultaneous effects of different nanoparticles integrations on fiberglass sandwich panels under low-velocity impact

The incorporation of nanoparticles has been recognized as one of the methods of reinforcement of sandwich panels as an effective substitute for popular materials such as metals. This study has examined the low-velocity impact responses of two groups of nanocomposite sandwich panels at different energy levels. Clay-silica nanoparticles and nanoclay-carbon nanotube (CNT) were integrated as nanofillers into the face sheets of sandwich panels. The sandwich panel with glass fibers/epoxy face sheets and a PVC core was fabricated by the hand layup method. The Contact force-time and contact force-displacement curves were recorded at various energy levels of 15, 30, and 50 J. The simultaneous presence of nanoclay and CNT increased impact resistance by 43.2%, 19.8%, and 10.26% at energy levels of 15, 30, and 50 J, respectively, in comparison with the reference sample without nano-particle whereas the presence of nano-silica with nano-clay at some weight fractions weakened the impact resistance. The analysis of SEM images indicates the proper distribution of nanoparticles and the uniform distribution of CNT leading to the increase in impact properties, which are compatible with the mechanical results.

Low-velocity impact response and energy absorption of Menger sponge-inspired fractal structures fabricated by selective laser melting

An innovative cellular structure, the Menger Fractal Cube (MFC), is introduced and studied systematically for the first time for low-velocity energy absorption applications. Formed through a recursive process of removing smaller cubes from a larger one, the MFC exhibits a hierarchically repeating pattern of cubical voids, resulting in a lightweight and highly complex structure. MFCs of three orders were fabricated using Selective Laser Melting (SLM) with highly ductile AlSi7Mg material. These structures were subjected to dynamic compression tests at impact velocities of 5.7 ms−1, 8 ms−1 and 10 ms−1 corresponding to input energies of 100 J, 200 J and 300 J respectively, both experimentally and numerically. Results reveal a unique failure mode involving buckling, shearing, shear band localisation and tensile yielding, resulting in a smooth force response in the plateau region. In contrast to conventional cellular structures, MFC structures exhibit multi-stage yield platforms without force drops. Notably, higher-order MFCs demonstrate extensively improved load bearing, crashworthiness, and energy-absorbing properties under dynamic loading conditions. This study provides crucial insights for optimising Additive Manufacturing (AM) cellular structures for dynamic energy absorption scenarios, with implications for automotive, sports, aerospace, and defence applications.

Nonlinear low-velocity impact response of magneto-electro-elastic beams with initial geometric imperfection

Nonlinear low-velocity impact response of magneto-electro-elastic beams with initial geometric imperfection

Impact response and compression-after-impact properties of foam-core sandwich composites incorporating scrap tyre rubber particles

Integrating scrap rubber particles as fillers into polymer matrix composites offers a cost effective and environmentally sustainable pathway to manage tyre waste through the creation of value-added products. This research explores the low-velocity impact (LVI) response and compression after impact (CAI) properties of rubberised foam-core glass fibre-reinforced epoxy (GFRE) sandwich composites. Syntactic foam cores integrated with rubber particles were manufactured using vacuum-assisted resin transfer moulding (VARTM). The compression properties of rubberised foam core, vital for resisting impact damage during LVI, were examined. Results show more than 40% reduction in compression strength and modulus of the syntactic foam upon the inclusion of 33 wt.% rubber particles. The LVI response and residual compression properties of rubberised foam-core composites were also evaluated. Rubberised foam cores caused a marginal reduction in the peak impact force and led to approximately 60% reduction in the delamination area. The pre-impact compression strength was unaffected by rubber particles within the core as the GFRE face sheets carried most of the compression load. Post-impact compression strength was slightly higher in rubberised foam-core composites due to reduced delamination. Digital Image Correlation (DIC) analysis tracking of the strain evolution during CAI experiments revealed the stress-raising effect of the impact damaged region. This study showcases sustainable scrap tyre management through the inclusion of rubber particles into foam-core composites without substantially reducing in-plane compression properties before or after low-velocity impact.

Analysis of Free Vibration and Low-Velocity Impact Response on Sandwich Cylindrical Shells Containing Fluid

Analysis of Free Vibration and Low-Velocity Impact Response on Sandwich Cylindrical Shells Containing Fluid

Low Velocity Impact Response of Carbon Fiber Composite Laminates with Surface Glass Fibers

Low Velocity Impact Response of Carbon Fiber Composite Laminates with Surface Glass Fibers

Low-velocity impact response of hybrid core sandwich panels with spring and strut cores filled with resin, silicone, and foam

Advancements in the load-bearing capacity of composite panels open doors to high-performance applications. The integration of additive manufacturing allows for the creation of intricate core designs effortlessly. Hybrid cores, combining structural elements with infill materials, play a crucial role in enhancing panel impact resistance while maintaining its low weight. This study compares sandwich panels incorporating spring and octet strut structural elements infused with different materials—silicon, foam, and epoxy resin—evaluating their energy absorption capabilities. Additive manufacturing is employed to produce these panels with structural elements then subsequently filled with infills. The drop tower test is utilized to experimentally assess panel behavior under low-velocity impact. Design of experiments and statistical analysis are used to examine the influence of core height, impact height, core geometry, and filling type on the damaged area and impactor penetration. Results showed that the strut-based structure performed better than other structures in preventing penetration, with a damaged area reduction from 501.45 to 301.58 m2 compared to the spring core. The addition of foam or silicon reduced the impact damage to the front and the back sheets, with silicon infills proving to be the most effective, reducing penetration by reducing penetration by about 60%. The depth of impact was measured, with results indicating that the truss core displayed the smallest specific depth of penetration. A decision tree model predicted that a sandwich panel with a spring core would have a 100% chance of perforation while a filled core showed a significantly reduced penetration risk.

Comparison of the dynamic characteristics of GFRP, CFRP, and hybrid composites subjected to repeated low‐velocity impact

AbstractThe current study used the vacuum‐assisted hand lay‐up method (VAHLM) to manufacture glass fiber‐reinforced polymer (GFRP), carbon fiber‐reinforced polymer (CFRP), and glass/carbon fiber‐reinforced hybrid composites to examine the influences of fiber materials and hybridization on the repeated low‐velocity impact (LVI) responses. In this regard, the manufactured composites were exposed to repeated LVI loading at 3 m/s under 25.2 J impact energy, and thus dynamic characteristics such as total impulse, contact/bending stiffness, interaction time, peak force/displacement, and absorbed‐rebounded energies depending on the impact number were acquired. LVI tests were continued until penetration was observed in the composites, at which point the penetration threshold numbers for each composite type were acquired. Furthermore, the macro‐scale damage analyses depending on the impact number were gradually examined, and the impacts of hybridization and fiber material on the damage mechanisms were determined. The study found that GFRP, hybrid and CFRP composites had the highest impact resistance, respectively, and that glass fiber‐reinforcement is well‐suited for applications that require higher impact resistance. When the average penetration threshold numbers for the composites were examined, it was observed that GFRP composites had approximately five times higher penetration threshold numbers than CFRP composites and that hybrid specimens exhibited similar properties to CFRP composites in terms of impact resistance. This scenario was linked to the various deformation capabilities of glass and carbon fibers, and it was concluded that the high‐deformation capability of the fibers improved the penetration threshold numbers.Highlights Effects of hybridization and fiber material on LVI responses were examined. Fiber material has a significant influence on impact resistance. Penetration threshold number can be associated with the fibers' strain capability. The adhesion factor plays an active role in the damage of hybrid specimens.

On Low-Velocity Impact Response and Compression after Impact of Hybrid Woven Composite Laminates

This paper aims to study the low-velocity impact (LVI) response and compression after impact (CAI) performance of carbon/aramid hybrid woven composite laminates employed in marine structures subjected to different energy impacts. The study includes a detailed analysis of the typical LVI responses of hybrid woven composite laminates subjected to the impact with three different energies, as well as a comparative analysis of cracks and internal delamination damage within impact craters. Additionally, the influence of different impact energies on the residual compressive strength of hybrid woven composite laminate is investigated through CAI tests and a comparative analysis of internal delamination damage is also conducted. The results indicate that as the impact energy increases, the impact load and CAI strength show a decreasing trend, while impact displacement and impact dent show an increasing trend. The low-velocity impact tests revealed a range of failure modes observed in the hybrid woven composite laminates. Depending on the specific combination of fiber materials and their orientations, the laminates exhibited different failure mechanisms. Buckling failures were observed in the uppermost composite layers of laminates with intermediate modulus systems. In contrast, laminates with higher modulus systems showed early damage in the form of delamination within the top surface layers.