bluuebunny/crossref_metadata_2025_split huggingface dataset:
Simulation and experimental analysis of explosive reactive armor collateral damage
Authors: Peng X F , Xiang H , Liang J Y , Zhong Y W , Bai F Q , Huang W B , Gao Y L , Yang Y 
Published: December 2024

Abstract
Addressing the issue of collateral damage caused by the structural design of explosive reactive armor (ERA) containers to close-combat units, this study combines simulation with experimental validation to focus on the damage intensity and range of ERA package side strips on target plates at different distances and positions during the defense against long-rod penetrators. Simulation analysis shows that the main collateral damage of the explosive reactive armor is the side strip of the cartridge flying in the normal direction of the target plate, and the fragmentation speed is about 760m/s. The experimental results show that collateral damage is relatively minor to the rear-side but concentrated primarily on the frontal-side. Under the action of explosion, the flight path of the side strip of the plate cartridge is stable, and the degree of collateral damage caused by it is the greatest. The flight path of the side strip is mainly in the range of the vertical scattering Angle of about 33° and the horizontal scattering Angle of about 31°. The distance attenuation of shock wave is much greater than the velocity attenuation of fragment, making debris the primary factor in collateral damage. The fragment speed range is 700m/s∼800m/s, the diameter (or length) of the penetrated hole is about 8mm∼20mm, and the fragment size is about 6mm∼10mm
Experimental study on the effect of energy absorption and wave attenuation of sand wall in ground motion under explosion
Authors: Song Shiqian , Shi Yongxiang , Li Zengyue , Huang Xiaofei , Xing Yuanding 
Published: December 2024

Abstract
Sand walls have a good energy absorption and wave attenuation effect on explosion shock waves, which can also have an impact on the seismic waves generated by the evolution of shock waves. In order to study the effect of sand wall in energy absorption on the results of explosive ground motion, four repeated explosion experiments were conducted by using different sand wall configurations. A ground motion measurement system was designed to measure the velocity at different distances from the explosion center. The measurement and analysis results showed that under the action of the sand wall, the peak velocity and the total energy based on vibration velocity both significantly decreased, fully demonstrating the energy absorption and wave attenuation effect of the sand wall. The sand wall also has an impact on the cube root similarity rate, resulting in the distribution of ground motion parameters no longer strictly following this law, but the sand wall has no significant impact on the frequency distribution. Under different sand wall configurations, the circle shaped sand wall has a better energy absorption and wave attenuation effect, while the circle shaped sand wall with nested circle shaped ends can enhance the energy absorption and wave attenuation effect by 21%.
Determination and verification of parameters in the dynamic constitutive for Inconel 718 superalloy
Authors: Yang L F , Wen H M 
Published: December 2024

Abstract
Inconel 718, which is a nickel-based superalloy material used in aero engines, may be subjected to intense dynamic loading in an accidental engine failure. However, the material models for Inconel 718 employed in existing studies can not describe the mechanical behaviors under complex stress states, high strain rates and elevated temperatures satisfactorily. In this paper, various parameters of a previously proposed dynamic constitutive model for Inconel 718 are determined and verified. First, the parameters of strength, strain rate effect, temperature effect and failure for precipitation hardened Inconel 718 are calibrated against various material tests. Then, the parameters are verified by comparing the numerical results obtained from the dynamic constitutive model with the corresponding ballistic test data. It transpires that the numerical results agree well with the test data, which demonstrates the accuracy and effectiveness of the dynamic constitutive model for Inconel 718. It can also be concluded that the consideration of Lode angle effect and precise descriptions of strain rate and temperature effects are significant for the reproduction of mechanical responses of Inconel 718 plates under intense dynamic loadings in numerical simulations.
Novel damage criterion in database form based on component-level vulnerability assessment
Authors: Feng Bo , An Fengjiang 
Published: December 2024

Abstract
Target vulnerability assessments commonly involve large and complex components such as engines exhibiting a lack of systematic and comprehensive representation of damage criteria. This study presents a novel approach to characterizing the damage criteria of large and complex components when impacted by fragments in the form of a database. The damage criteria are formulated based on component-level vulnerability assessments and presented in tabular format, providing information on the component damage probability under the impact of fragments with different velocities, masses, and directions, as well as the residual velocity and mass data for fragments passing through the component. A servo is chosen as a representative component to establish damage criteria in the form of a database. Steel fragments, with masses ranging from 4 g to 7 g and velocities from 100 m/s to 1800 m/s, are employed to impact the servo component from 26 different directions. A total of 1144 sets of vulnerability data for the component are collected, including the damage probability of the servo and the residual mass and velocity of fragments. These data serve as comprehensive damage criteria for the servo component. A comparison between these component damage criteria in a database form with those derived using an equivalent target method shows that the former approach offers greater accuracy and adequacy in representing the damage characteristics exhibited by large and complex components than the latter. the proposed method in this study to represent damage criteria for large complex components in the form of a vulnerability database has broad application prospects and provides new ideas for future research on damage criteria for components.
Experimental and numerical study on jet penetrating multi-layer metal rubber air-spaced composite target
Authors: Qiong Qi , Lei Zhang , Xun-cheng Guo , Dong-jiang Zhang , Yun-hui Hou 
Published: December 2024

Abstract
A multi-layer metal rubber air-spaced composite target was designed. Based on the 140 mm caliber shaped charge, the penetration test and simulation study were carried out. By analyzing the damage of the target plate and the interaction process between the jet and the target plate in the simulation, the interference mechanism of the composite target to the jet is revealed. The equivalent armor thickness and anti-jet penetration ability of the composite target under oblique penetration with large inclination angle are obtained by using the equivalent criterion of residual penetration depth. It is concluded that the multi-layer metal rubber air-spaced composite target can not only reduce the load of the armored vehicle, but also has good anti-jet penetration performance, which can provide support and basis for the design of other rubber composite target structures.
Study on the Damage Effect of Shaped Charge Jet Penetrating Multi-layer Spaced Inclined Target Plates
Authors: Wang M , Qiu J W , Chen X W , Wang Y S , Liu F 
Published: December 2024

Abstract
This study aims to investigate the formation characteristics and penetration performance of multi-layer spaced inclined target plates by shaped charge jets. Based on a multi-material fluid-structure interaction algorithm, a three-dimensional simulation model of a shaped charge jet penetrating multi-layer spaced inclined target plates was established. The process was numerically simulated using a nonlinear finite element program. Relevant validation experiments were conducted, and the causes of discrepancies between numerical simulations and experimental results were analyzed. The effect of the target plate placement angle on the damage effect of the shaped charge jet penetrating multi-layer spaced inclined target plates was discussed. The results show that the numerical simulations are in good agreement with the experimental results. The impact of the shaped charge jet on the spaced inclined target plates diminishes as the placement angle increases. The penetration time and velocity reduction values of the jet on various target plates at different angles were measured. It was found that the size of the openings in the target plates positively correlates with the placement angle, and the symmetry of the opening shapes degenerates with increasing placement angles.
Study on the blast resistance of concrete reinforced with multi-scale hybrid fibers
Authors: Chengyuan Wang , Zhijun Wang , Zhijun Cheng 
Published: December 2024

Abstract
Hybrid fibers can greatly improve the toughness of concrete and enhance the blast resistance of concrete. In this study, nano-sized multi-walled carbon nanotubes, micron-sized calcium carbonate whiskers, and millimeter-sized steel fibers were added to the concrete to improve the cracking resistance of the concrete on a nano-micron-millimeter multi-scale. The blast resistance of multiscale hybrid fiber-reinforced concrete with different TNT equivalents and the volume content of steel fiber were investigated by numerical simulation methods. The results showed that, with the addition of multi-scale hybrid fibers, the concrete plate in the TNT equivalent of 200 g occurred in a moderate degree of delamination failure, in the 400 g TNT equivalent, the MSHFPC plate penetration damage occurred, compared with the plain concrete plate, the blast resistance significantly improved; the explosion pit diameter with the increase in the TNT equivalent increased; with the increase in the volume content of steel fibers, the number and length of cracks in concrete plates significantly decreased, and the blast resistance performance significantly increased.
Damage Patterns and Boundary Research on the Internal Explosion of Shell-Encased Warhead within Compartments
Authors: Deyang Zhang , Xingxing Wu , Juan Chen , Nu Zhang , Yanjie Zhao 
Published: December 2024

Abstract
This paper primarily focuses on basic ship compartment as the research object, conducting experiments on internal explosion of shell-encased warheads to ascertain the corresponding damage patterns and the damage boundaries under current conditions. Additionally, numerical computation methods are employed to gain a more detailed understanding of the entire transient testing process and to validate the reasonableness of the computational models. Based on the experimental data, observed phenomena, and simulation results acquired, this paper draws the following conclusions: for internal explosion test of shell-encased warhead, the theoretical formula provides good prediction for the shock pressure, but there is a considerable discrepancy in the quasi-static pressure; a comparison between simulation and test results shows that the damage pattern from the internal explosion of an equivalent mass of bare charges within a compartment is consistent with the experiment, although the damage boundary is underestimated; under the current test condition, the damage boundary of the warhead extends beyond three compartment walls. The research presented in this paper can better inform the design of naval structures and provided foundational experimental data for the internal explosion of shell-encased warhead within compartments.
Study on the Constitutive Relationship and Mechanical Properties Fitting of SFRC Based on Optimized BP Neural Network
Authors: Ma Pengsheng , Zhou Fengjun , Liu Li , Li Feng , Kang Huaiqiang , Gao Hang , Sun Yunhou 
Published: December 2024

Abstract
In order to accurately characterize the complex mechanical behavior of steel fiber reinforced concrete (SFRC) under high-speed impact and accurately describe the constitutive relationship of its mechanical behavior, the dynamic compression test of plain concrete and SFRC with two different fiber contents, 0.5% and 1.5%, was carried out based on the split Hopkinson pressure bar (SHPB). Firstly, the stress-strain curves and their failure morphology at different strain rates in the range of 47s−1-214s−1 are obtained; Next, a back propagation (BP) neural network prediction model optimized by particle swarm optimization (PSO) algorithm was established based on SFRC stress, taking strain rate, fiber content, and true strain as input parameters, and outputting the true stress; Finally, the fitted constitutive relationship of SFRC is obtained by inference based on the established model. The results show that SFRC has a strong strain rate enhancement effect in strength, and its peak stress will be continuously enhanced with the increase of strain rate. The steel fibers can effectively inhibit the generation and expansion of cracks, thereby improving the impact resistance of concrete. The PSO-BP neural network model proposed in this paper can effectively fit the constitutive relationship of SFRC, and the deviation of the model inference results is less than 10%, with the model correlation coefficient R of 0.9563 and the average relative error E of 5.92%. At the same time, the proposed model can also be used for the prediction of the performance indexes of elastic modulus and ultimate compressive strength, and the model has a good generalization ability and good fitting accuracy.
Compressive Mechanical Properties of a New High Density NiW Alloy
Authors: Yang Jincheng , Chen Chunlin , Ma Kun , Cao Jin , Yin Lixin , Gao Pengfei , Feng Na 
Published: December 2024

Abstract
In order to apply a new high density NiW alloy to hollow kinetic energy penetrators, the mechanical properties of the alloy at high temperature and high strain rate are studied by Hopkinson pressure bar. The results show that the strength of the alloy decreases significantly with the increase of temperature, and the decreasing rate between 900°C to 1200°C is about 4 times that between 25°C to 900°C; the alloy has a strain rate strengthening effect, and the strain rate sensitivity increases with the increase of temperature under dynamic loading; unlike normal metals, the tangent modulus of the alloy does not decrease monotonously with the increase of temperature due to the precipitation of Ni4W phase, the solid solution strengthening mechanism and the dynamic recovery mechanism jointly determine the trend of the tangent modulus.
Numerical study on the effect of initial detonation points on energy output structure
Authors: Ying Yuan , Guotao Yang , Yongxin Wen , Yilei Li 
Published: December 2024

Abstract
A numerical simulation was employed to investigate the influence of initiation modes on the energy output structure of cylindrical explosives. Based on the numerical simulation results of the response behaviours of identical explosive configurations under different initiation scenarios, including one-end initiation, two-end detonation, centre point detonation, and axial detonation, combined with the development and propagation rules of detonation waves as well as the response behaviour of the shell, the temporal and spatial distribution characteristics of the output energy distribution of explosives under various initiation modes were obtained. The research findings provide a theoretical foundation for the design of explosive initiation points, the regulation of the directional energy output of warheads, and the enhancement of energy utilization efficiency.
The Protective Capability of Helmet Against Blast Wave to Prevent Traumatic Brain Injury
Authors: Wenchao Zhang , Bin Qin , Liang He , Yang Wu 
Published: December 2024

Abstract
Blast-induced traumatic brain injury (b-TBI) is a kind of prevalent military injury in combat casualty care, yet little is known about the protective capability of typical helmet structure against blast wave. In this study, a head model under blast was used for experimentally and numerically research. A finite element model with a typical human head structure was established. Tests on the distribution of air pressure field of the unprotected head, typical combat helmet protected head, combat helmet protected head with face shield, motorcycle helmet protected head were carried out after the explosion of 50gTNT action at 1m. Various test conditions were analyzed by numerical simulation method. The interaction law between the blast wave and the head under the protection of different helmet structures was obtained. Combined with the brain tissue pressure, the protective effect of different helmet structures on the blast wave was analyzed. The results show that increasing the helmet protection area is a good protection strategy for blast wave and the research suggests a possible protection strategy for blast wave often associated with military concussions.
Effect of considering thermoplasticity of gun steel on thermomechanical coupling response of barrel
Authors: Wang Haoyu , Fu Jiawei , Chen Longmiao , Liu Nailin , Pang Jianing 
Published: December 2024

Abstract
To explore the effect of considering thermoplasticity of gun steel on the thermomechanical coupling of the barrel during artillery firing, the thermoplastic coupling behavior of the barrel under transient thermal and mechanical loads is investigated. A thermomechanical coupling finite element model of the barrel was established. The transient temperature field and stress field of the barrel during the gun firing process were analyzed. By comparing the results of the thermoelastic model with that of thermoplasticity model, the effect of considering thermoplastic of gun steel on thermomechanical coupling response of barrel was investigated. The results show that the peak of Mises stress evolution considering thermoplasticity of material in the bore of the barrel is significantly reduced during the gun firing process, and the hoop stress evolution appears double-peak phenomenon. In addition, at the peak moment of bore pressure, the peak values that the hoop and Mises stress distributions along the radial direction at the midpoint of the land are reduced by 14.5 % and 20.9 %, respectively. This paper can provide a reference for the design of a large-caliber barrel.
The attenuation characteristics and optimization design of polyurethane foam bulkhead to blast wave
Authors: Shouren Wang , Pengwan Chen , Chuan Zhao 
Published: December 2024

Abstract
Polyurethane foam has the characteristics of low density, nonlinear mechanics and energy absorption, and has been widely used in the research of shock wave attenuation. In order to realize the effective attenuation of the blast wave, the attenuation process of the shock wave in the medium is simulated by Autodyn. The impact ignition simulations were carried out for the Comp B impact ignite TNT under the bulkheads. The results show that the explosion-proof performance of the composite bulkhead is signi2icantly better than that of the single medium bulkhead. The combination of PR 6720 (polyurethane foam) and 45#steel can greatly attenuate the blast wave. The impact impedance matching relationship of the bulkhead and the medium on both sides should be used as an important design factor when designing the bulkhead.
Study on the Formation Characteristics of Composite Damage Elements
Authors: Zheng Juhong , Yu Rui , Wang Yajun , Zhao Junmin 
Published: December 2024

Abstract
More innovative and high technologies are being emerging endlessly, and more requirements for comprehensive damage effect have been further proposed. As a results, the single usage method and damage effect can no longer fully fit the future trends. In this paper, the formation characteristics of EFP and the scattering characteristics of prefabricated fragments was studied on the basis of the structure with composite damage elements, such as prefabricated fragments and explosively formed penetrator (EFP). The results show that the composite damage elements can form high-velocity projectiles with an initial velocity of 2230 m/s in the axial direction and a tungsten ball array with the scattering velocity in the range of 750 to 840 m/s. Moreover, if prefabricated fragment structures are removed, the change of EFP formation characteristics is not obvious. However, shaped-charge structure play an evident influence in the scattering velocity of fragments. Compared to the structure with single damage elements, the average velocities of fragments of composite structure are higher and its scattering angles are more widely, maximum scattering angle increasing from 16° to 20.1°.
Fragmentation Process and Combustion Performance of the Grain-molded Gun Propellant
Authors: Jia ZJ , Hu XB , Liu ZY , Yan WR , Wen XM , Cui HL , Li CH , He L 
Published: December 2024

Abstract
In order to research the impact fragmentation and combustion behavior of the grain-molded gun propellant and guide the design of ammunition charge structures, experiments were conducted using constant-volume gas pressure impact and closed bomb tests. Tests were conducted and results were obtained, including the combustion pressure variation curves of the grain-molded gun propellant as well as its disintegration and fragmentation states under different termination pressures. The study analyzed the impact fragmentation process and the progressive combustion characteristics of the grain-molded gun propellant.. The results show that the combustion of the molded gun propellant does not follow the parallel layer combustion rule; The molded gun propellant exhibits inconsistencies in burning rate and disintegration fragmentation, making it difficult to achieve simultaneous ignition and combustion. Additionally, the molded gun propellant can reduce the gas generation rate during the initial stage of cartridge firing, thereby extending the combustion duration.
Study on the forming of eccentric sub-hemisphere tungsten tantalum alloy liner
Authors: Yu Wang Zhe , Bing Li Wei , Bin Li Wen , Ming Wang Xiao 
Published: December 2024

Abstract
In order to obtain a tantalum tungsten alloy rod penetrator structure with good performance indicators, LS-DYNA numerical simulation software is used to study the effects of different structural parameters (such as curvature radius of liner, liner thickness, liner thickness variation rate, eccentricity, and the height of charge) of the eccentric sub-hemispherical structure liner on the formation of Ta-2.5W rod penetrator, and the optimal range of each structural parameter is determined. Through orthogonal optimization design, the primary and secondary order of the influence of various structural parameters on the formability of Ta-2.5W rod penetrator is obtained, and the optimization scheme for Ta-2.5W rod penetrator is determined (the internal curvature radius R2
of the liner is 0.9571Dk
, the top thickness t of the liner is 0.0286Dk
, the eccentricity d of the liner is 0.0429Dk
, the thickness variation rate s of the liner is 1.25, the diameter Dl
of the liner is 0.9Dk
, and the charge height l is 1.0Dk
, where Dk
is the charge diameter). The results show that the optimized Ta-2.5W rod penetrator scheme has good performance indicators, with a speed V of 1830.7m/s, an aspect ratio L/D of 7.13, a compactness N of 0.84, and a necking ratio M of 0.30. Compared to pure tantalum, the Ta-2.5W rod penetrator is superior because pure tantalum will break under the same working conditions.