bluuebunny/crossref_metadata_2025 huggingface dataset:
Failure analysis of semiconductor bridge component in humid and hot environment
Authors: Xie Rui Zhen , Li Ming , Fu Pei , Zhang Jing Xin , Bai Bing , Cheng Ni , Yao Hong Zhi
Published: December 2024

In order to solve the problem of failure during the storage of semiconductor bridge initiating explosive devices, the alternating humid and heat test of semiconductor bridge component was carried out according to GJB5309.30-2004 test method for initiating explosive devices -part 30: Humid and heat test. The semiconductor bridge component was characterized by means of resistance measurement, microscopic characterization, energy spectrum test, roughness test, etc. The resistance at the wires showed that the failure rate of Sample 1 and Sample 2 were 11% and 88%, respectively after 28 days of alternating humid and heat test, and the resistance of the failed sample at the solder pads did not change. The scanning electron microscope and energy spectrum test results show that there is significant corrosion at the wires end, and the component such as Fe, Co, Ni appeared at the wire end after the humid and heat test. The roughness test results show that the surface roughness of sample 1’s wire is smaller than that of sample 2. These indicate that the failure mode of semiconductor bridge components in humid and heat environments is atmospheric corrosion, and the surface state of the wire affects their failure efficiency.
Damage and Fracture Behaviour of Bearing Beam for the PyroMEMS Safe and Arming (S&A) Device
Authors: Wei Liu , Ren Xiao-Ming , Liu Lan , Chu En-Yi , Zhang Hai-Ying
Published: December 2024

A novel PyroMEMS safe and arm device (S&A) by using torsion spring to lock the slider are presented, and the S&A device is composed of an igniter layer, an actuation layer and a lid layer. Due to strength of the bearing beam determined the arming process of PyroMEMS S&A device, a simulation model was built by using commercial explicit dynamic software to calculate damage and fracture behaviour of the bearing beam. Critical sizes of the bearing beam were computed under different conditions. The results showed that damage behaviour between the normal and necked-shape bearing beams were quite different, and the double-beam structure could not realize the arming function compared to the single-beam structure. The critical fracture pressure increased from 62.5MPa ± 2.5Mpa to 102.5MPa ± 2.5Mpa, as the width of normal bearing beam increased from 100μm to 150μm. Only if the width of normal bearing beam was less than 149.4μm, or the angle β of necked-shape bearing beam was greater than 3.4°, the bearing beam could be broken to release the slider and furtherly realize the arming function. It is of vital importance to guide the design of PyroMEMS S&A device.
Analysis of mechanical properties of copper tantalum alloy material
Authors: Hong Bihui , Li Wenbin , Zhu Wei , Li Yiming , Chen Peng
Published: December 2024

Alloy material is one of the important factors affecting the penetration ability of shaped charge warhead. It is of great significance to study the mechanical properties of copper-tantalum alloy material for its application in shaped charge warhead. The mechanical tests of alloy materials at different temperatures and different strain rates were carried out by material universal testing machine and split Hopkinson pressure bar. The experimental results show that under quasi-static compression and dynamic compression, the plastic flow stress of Cu-40Ta material increases with the increase of strain rate, and has significant strain hardening effect. The plastic flow stress decreases with the increase of temperature, and there is thermal softening effect. The yield strength increases with the increase of strain rate, and the material has obvious strain rate strengthening effect.
PD Proportional Guidance Method for Strapdown Guided Air-to-ground Missile
Authors: Wang Dong , Zhao Yangyang
Published: December 2024

Aiming at the problem that the guidance accuracy of strapdown guided air-to-ground missile is poor and it is difficult to meet the demand of precise strike to ground target, a design method of strapdown guided PD proportional guidance law is proposed. Firstly, an improved α–β–γ filtering method is designed to estimate the angular velocity of line of sight(LOS) and angular acceleration of LOS of strapdown guidance. Then, the PD proportional guidance method is formed by using the estimated angular velocity of LOS and angular acceleration of LOS. Finally, the simulation compares the proportional guidance law based on the estimated angular velocity of LOS with the PD proportional guidance law based on the estimated angular velocity of LOS and angular acceleration of LOS. The simulation results show that the proposed PD proportional guidance law can effectively improve the strapdown guidance accuracy.
Research on Top-Down design of launcher fairing mechanism equipped on Air-to-Ground missile carried by UAV
Authors: Pang Yu , Li Zeyang , Zhang Qi , Yu Lei , Yang Li , Xu Yangyang , Liu Ruiqing
Published: December 2024

Reconnaissance/Strike Unmanned Aerial Vehicle (UAV) is advanced strike unmanned equipment with long range. Tube-launched technology is one of the commonly used launch technologies for air-to-ground missiles carried by UAVs. Traditional launchers sealed by sealing film have disadvantages in aerodynamic characteristic and launch safety, restricting the combat effectiveness of UAVs. In this article, the influences of airspeed and aspect ratio on aerodynamic characteristics of fairing are studied based on CFD. The relationship between the aerodynamic drag torque and the open angle of fairing is established. A top-down design method of fairing mechanism is proposed which is capable of reducing aerodynamic drag, opening transmission path and being reset automatically. The virtual prototype of the fairing mechanism is built and mechanical dynamics analysis is carried, verifying the rationality and feasibility of the design. The effects of the fairing mechanism on the lift-drag ratio and the range of one advanced reconnaissance/Strike UAV is displayed that the values are improved by 15.2% and 613 km, respectively.
Research on cavity evolution and motion characteristics of supercavitating projectiles during asynchronous parallel water entry
Authors: Qi Xiaobin , Wang Rui , Li Ruijie , Lu Lin , Wang Jiawen
Published: December 2024

To study the performance of supercavitating projectiles in asynchronous parallel entry into water, this paper establishes a numerical simulation method for supercavitating projectiles in asynchronous parallel water entry based on finite volume method, VOF multi phase flow model, and overlapping grid technology. At the same time, high-speed cameras and light gas guns were used to conduct high-speed water entry experiments on a single projectile, and the reliability of the numerical method was verified by comparing simulation results with experimental results. Subsequently, numerical simulations and analyses were conducted on the cavity evolution and motion characteristics of the front and rear projectiles under different initial spacing and different water entry sequences. The research results indicate that when the initial distance between the front and rear projectiles is 0.5 times the length of the projectile, the front projectile is unable to generate complete cavities to wrap the projectile body due to severe compression from the rear projectile, which seriously affects its movement and ultimately leads to instability. As the initial spacing increases, the influence of the rear projectile on the surrounding cavities of the front projectile weakens. Whether the upper projectile enters the water first or the lower projectile enters the water first, both move smoothly. For the rear projectile, due to the continuous effect of the front projectile cavity, its cavity is always asymmetric, and its motion stability is affected. When the spacing is 0.5 times the length of the projectile, the rear launched projectile deflects inward and becomes unstable. When the spacing is 1 time the length of the projectile, it moves steadily. When the spacing is 2 and 3 times the length of the projectile, it deflects outward and becomes unstable. Regardless of which projectile enters the water first, this motion pattern is basically consistent.
Experimental investigation of mechanical responses of helmeted headforms under the ballistic impact
Authors: Harmukh Atul , Ganpule Shailesh
Published: December 2024

Ballistic impact induced head injury is a massive concern in contemporary asymmetric warfare. The performance of the ballistic helmets and the associated mechanical responses of headforms against ballistic impact are highly sought. The ballistic assessment of the helmet is traditionally evaluated based on the perforation of the helmet and back face deformation (BFD) of the helmet. However, the link between BFD and head injury remains unclear. Toward this end, we have investigated the mechanical responses (BFD, head kinematics (linear and angular)) using rigid headform and flexible headform under the ballistic impact with using 9 mm bullet (bullet velocities: 430 ± 15 m/s). The front, oblique (30o̱ to the sagittal axis), right, back, and left orientations were considered for the ballistic impact. Our results indicate that the flexible headform influenced head kinematics significantly, although the differences in BFD between the rigid and flexible headforms were minimal. Overall, these findings offer insights and new data on the ballistic performance of helmeted headforms. This information is crucial for designing and developing next-generation helmets and for improving testing protocols to better evaluate the effectiveness of ballistic helmets.
Study on the Influence of Combustible Cartridge Force of Propellant on the Pressure Wave of Modular Charge
Authors: Guo Yinghua , Li Ruijing , Dong Yancheng , Chen Pengjie
Published: December 2024

In order to study the influence of the change of force of propellant of combustible cartridge case on the interior ballistic performance of gun, the combustion performance tests of four combustible cartridge case formulations were carried out, and the pressure-time curve of actual combustion process was obtained. On this basis, the combustion law of combustible cartridge cases with different force of propellant is obtained, and the combustion law is introduced into the two-phase flow simulation model of modular charge, and the influence law of combustible cartridge case force of propellant change on the pressure wave in the interior ballistic process of gun launching module charge is obtained by simulation. The research results have certain reference value for improving the design of combustible cartridge case with large-caliber modular charge.
Formation behavior of truncated hypervelocity shaped charge jet
Authors: Li P L , Wang K , Zhang X Y , Li Y L
Published: December 2024

Truncated liner shaped charge(TLSC) structure can form truncated hypervelocity shaped charge jet(THSCJ), which is significantly different from the ordinary shaped charge jet(OSCJ). The formation behavior of THSCJ is studied by numerical simulation and theoretical analysis. The results show that the additional liner can enhance the propagation of detonation wave and the improvement of jet velocity. The head velocity of THSCJ is obviously higher than that of OSCJ. The influence of liner structure on the formation performance of THSCJ is investigated by changing the protruding length of the additional liner and the height of the truncated liner. Within the given range of structural parameters, when the protruding length of the additional liner is 1.5mm, and the truncation height is 1/3 of the total height of the liner, the performance characteristics of THSCJ is more stable.
Scheme Optimization of Artillery Based on Combination Weighting Approach
Authors: Huang Ke , Yang Jianwei , Wei Jiqing , Tang Pengbo , Lu Yuxiang
Published: December 2024

The system efficiency method can be used to evaluate and select from the multiple schemes in the demonstration and scheme design stage. Taking the multi-scheme optimization of a new type of equipment carrying artillery with different calibres as the demand, the using requirements and combat environment of artillery are analyzed, and the inherent capability evaluation system composed of shooting capability and destructive capability is constructed. Due to the great difference in the judgment of indicator weights by experts from different industries, the combination of subjective weighting approach and objective weighting approach is used to determine the weight of each indicator, and the multi scheme evaluation model of artillery firing is established. The evaluation results show as follows: when using subjective weighting approach alone, the scheme with comparative advantage can’t be picked out because of the prefer to the maximum effective range by experts; when using objective weighting approach alone, the sample data vary greatly from indicator of maximum firing rate, but the change of the indicator has no significant impact on the combat effect; and when using the combination weighting approach, the evaluation results can avoid not only the preference of experts, but also the deviation of weights from the actual demand caused by the large difference between sample data.
Optimized design of a lightweight frame based on padded fabric
Authors: Chen Chen , Wang Hua-Ting , Zhang Tai-Ping , Huang Chen-Xu , Meng Fan-Zhe
Published: December 2024

In order to solve the problem of unreliable connection between the subframe and the chassis girder under the action of shooting load, which leads to the reduction of the stiffness and strength of the connection between the bodywork part and the chassis girder, and affects the shooting accuracy of the bodywork, combined with the structural characteristics of the rigid connection between the subframe and the chassis girder, the fabric filling and bolt preloading connection method is proposed, the finite element model is established, and the deformation of the connection between the original and the improved scheme is analyzed. The results show that under the action of shooting load, the deformation of the bodywork mounting surface can be effectively reduced and the shooting accuracy of the bodywork can be improved by bolt pretensioning and spinning fabric filling, which provides a certain reference for the optimal design of the lightweight frame.
Microstructure and mechanical properties of high nitrogen austenitic stainless steel welded joints using tandem gas metal arc welding
Authors: Li Jianguo , Jia Dongsheng , Cui Jianwei , Zhao Yinhu , Ji Huang , Zhang Hanfu , Wang Zhiyong , Wang Xu , Li Yi , Zhao Leicheng
Published: December 2024

High nitrogen austenitic stainless steel welded joints were obtained by gas metal arc welding and tandem gas metal arc welding, respectively. Compared with single wire welded joint, tandem welded joint was investigated. Although tandem welding has less welding pass than single wire welding, higher heat input and cooling rate are obtained. High heat input is the main impact factor on low fraction of δ-ferrite and high fraction of precipitates formed during tandem welding. Moreover, weld seam after tandem welding has higher dislocation density and Schmid factor along δ-ferrite, which results in the reduced tensile strength and yield strength, as presented in mechanical property testing. Less difference of elongation is obtained between single wire welding and tandem welding, as is consistent with Taylor factor results.
Method of missile formation positioning and tracking based on TDOA-DOA
Authors: Kong Weijie , Wang Yi , Dong Leiping , Li Yanzhao
Published: December 2024

With the development of science and technology, the battlefield environment of modern warfare has become complicated and complex, and it has become an important task to obtain information about enemy targets quickly and accurately. Accordingly, researchers from various countries have explored various positioning methods, which can be divided into active and passive positioning, among which passive positioning has received more attention due to its excellent concealment and anti-jamming ability. In this paper, the two methods of passive positioning, Direction of Arrival (DOA), and Time Difference of Arrival (TDOA), are used to study the positioning of missile formations in two- and three-dimensional space and to analyse the factors affecting their positioning accuracy.
Preparation and mechanical properties of 316L-Ti composites by Laser Powder Bed Fusion
Authors: Guo Xin , Li Xiaojun , Li Wei , Xie Changyou , Zhang Qiaoxin
Published: December 2024

To investigate the feasibility of additive manufacturing of energetic structural materials, this study fabricated 316L-Ti composites using Laser Powder Bed Fusion. The research examined the forming process parameters of 316L-Ti and analyzed the changes in relative density, defects, phases, and mechanical properties of the composites with varying laser energy densities. The results indicate that the primary defects in 316L-Ti composite samples are delamination and lack of fusion (LoF) pores. At high laser energy densities, delamination cracks are likely to occur, leading to significant delamination, warping, and even failure to form the samples. Conversely, at low laser energy densities, samples show minimal delamination but an increase LoF pores, leading to worsened mechanical properties. The addition of titanium results in the presence of both austenite and ferrite phases. Optimal results are achieved at a laser energy density of 120 W and a scanning rate of 1200 mm/s, yielding samples with minimal defects, achieving a density of 91.69% of the theoretical value, and demonstrating a compressive strength of 1191 MPa.
Determination of Relative Molecular Mass and Distribution of Methyl Vinyl Silicone Rubber by Gel Chromatography
Authors: Guo Wenjia , Hou Qianqian , Dong Yazhuo , Xu Feng , Zhu Tianyi , Zhang Wenshen , Song Lei , Li Shengkai
Published: December 2024

The relative molecular mass and distribution of methyl vinyl silicone rubber were determined by gel chromatography. The method was studied for single detector. The analytical conditions were established as follows: tetrahydrofuran as mobile phase, two PLgel MIXED-B columns in series, column temperature of 40 °C, and flow rate of 1 mL/min. The relative molecular mass of polystyrene standard substance was determined by this method. The relative standard deviation of the measured values was less than 3% (n=6), the relative error of the number average relative molecular mass was less than 10%, and the absolute value of the relative error of the weight average relative molecular mass was less than 1%.
Uncertainty based design methodology system for naval gun weapon
Authors: Li YD , Kang ZK , Ren G
Published: December 2024

With the continuous improvement of the requirements for progressiveness and economic affordability of naval gun weapon, the development of naval gun weapon is facing increasingly severe challenges. The current naval gun weapon are still based on deterministic design, but there is insufficient attention paid to the large number of random and cognitive uncertainty factors in the entire lifecycle process of naval gun weapon. These uncertain factors are often the root cause of a series of problems such as long R&D cycles, low manufacturing qualification rates, difficulties in use and maintenance, and low reliability. This article focuses on the current status of naval gun weapon design. Firstly, it analyzes the uncertainty factors and their impacts throughout the entire lifecycle of naval gun weapon. Then, it elucidates the method system and challenges encountered in uncertainty design. It points out that quantitatively evaluating and controlling performance dispersion in each stage of design is an effective method for formulating the optimal design scheme for comprehensive performance, reliability, robustness, and cost throughout the entire lifecycle.
Characterization of laser power on additive manufacturing of heterostructure parts
Authors: Li Shiyi , Feng Hengzhen , Lv Sining , Kan Wenxing
Published: December 2024

In order to meet the demand for low-cost and rapid prototyping of micro-small parts for highly dynamic microsystems, metal additive manufacturing technology has become one of the important means of manufacturing heterogeneous parts. In this paper, the residual stress and deformation generated by the rapid prototyping process of micro-small and complex parts under different laser frequencies are firstly simulated and analyzed, and then in order to check the resistance of the parts to high overload, the densities and hardnesses of the printed parts are experimentally tested. The results show that, on the basis of ensuring that the powder can be fully melted, the lower laser power, the smaller residual stress of the micro-small complex parts, the smaller deformation of the parts caused. The physical energy density also shows a certain correlation to the density and hardness of the specimen, the higher physical energy density, the higher density and hardness of the specimen.
Research on the performance optimisation method of linear array infrared detector based on pixel decomposition
Authors: Hu Shiyuan , Wu Yanjiang , Si Xinlu , Han Shaorong , Chen Huimin
Published: December 2024

Facing the background of proximity detection applications, this paper proposes an optimisation method based on pixel decomposition to improve the detection performance in view of the strong dark current and blind pixel rate problems brought by the increase of pixel size. By establishing the linear array infrared detection model, the influence of pixel size on detector system dynamic range, noise equivalent temperature difference, spatial resolution and other performance parameters is obtained. Based on the idea of pixel decomposition, a suitable resolution is chosen to decompose a large-size pixel, and the photoelectric conversion process of each sub-pixel is equated. The simulation verifies that the proposed optimisation method of the pixel decomposition improves the detection signal-to-noise ratio.
Application of 3D Gaussian Splatting target Reconstruction in short-range detection
Authors: Lou Wenzhong , Li Chenglong , Feng Hengzhen , Ding Nanxi , Zhang Zihao , Ma Wenlong , Wang Lin
Published: December 2024

The research presented in this paper successfully introduces the emerging 3D reconstruction technology to specific application scenarios, especially for the strict requirements of information authenticity and timeliness for reconnaissance equipment and platforms. Traditional methods have the problems of slow speed and damaged reconstruction quality in processing reconnaissance information. In order to solve the problem of limited computing power of aerial detection platform and improve the reconstruction quality and efficiency of complex scenes, this paper introduces three-dimensional Gaussian Splatting (3DGS) method for testing. Experimental results show that 3DGS has excellent performance in rendering accuracy and real-time performance, which can effectively meet the performance requirements of aerial detection platforms. We tested it on a virtual dataset, and the experimental results show that it can also maintain excellent performance in the real world.
Monte Carlo Analysis and Optimization of Inertial Switch Tolerance of a Proximity Fuze
Authors: Zhao Xin , Sa Haijing , Qiu Liliang , Zhang Wenyi , Song Rongchang
Published: December 2024

Aiming at the low operation rate of the firing mechanism of ammunition fuze, robustness analysis and probabilistic design methods were introduced into the fuze design to carry out system simulation research on performance prediction and optimization of the firing mechanism of ammunition fuze. In this paper, the dynamic model of the inertial impact switch of a proximity fuze is established, and the mechanism can be reliably triggered under nominal values by simulation method. Based on the Monte Carlo simulation of dimensional tolerance distribution, the trigger performance is evaluated. The contribution rate of each dimension variable to the target value is obtained by using the optimal Latin hypercube experiment design, and the variable tolerance with greater contribution rate is optimized by Pointer algorithm. After optimization, the range of variable Jdxh_f was optimized from 0.1274 to 0.1666 to 0.1274 to 0.1556. Finally, the optimized results were validated, with a uniform distribution yielding 0.003193517N, a bimodal distribution yielding 0.2230769N, and a normal distribution yielding 0.2778532N. The validation analysis of these results shows that the target value distribution data after optimization meets the design requirements. This study seeks a balance between performance reliability and manufacturing cost, which is of great significance to improve product performance and reduce manufacturing cost.
Research on aerodynamic and ballistic characteristics of rotary wing type aerodynamic layout rocket
Authors: Li Peng , Sang Manxian , Cao Wenjun , Tian Lin , Ma Yue , Zhang Kuan , Duan Tengfei , Cheng Yuyang , Du Meijie , Shi Yongpeng
Published: December 2024

Rockets with a rotating wing type pneumatic layout as the research object, using the method of numerical simulation of subsonic stage of the rocket was studied at different attack angles, Mach Numbers and aerodynamic characteristics under different conditions of rudder Angle, and obtained the corresponding pneumatic parameters, and the influence of the relationship between the aerodynamic parameters. The motion equations of rocket are established, the force and moment of rocket during flight are analyzed, and the ballistic characteristics under different muzzle velocity and different launch elevation are simulated and analyzed, and the ballistic effects of different muzzle velocity conditions are obtained.
Numerical simulation study on the matching of third-generation explosives and large-caliber reactive shaped charge
Authors: Yao Xiaoshuo , Yan Yueguang , Zhang Bo
Published: December 2024

In order to further study the matching problem between the third-generation explosives and the large-diameter active shaped jet charge, the jet forming characteristics and thermo-mechanical coupling characteristics were studied based on the AUTODYN-2D finite element analysis platform. The evolution behavior and distribution law of pressure field, velocity field and temperature field during the active jet forming process were analyzed, and the active jet forming law under different charge structures was analyzed. The numerical simulation results show that the large-diameter active energy-gathering structure under the condition of the third-generation explosive charge can form a stable active jet. With the extension of the jet forming time, the high-pressure zone and the high-temperature zone have obvious movement and diffusion phenomena. The high-speed zone moves from the middle of the axis to the head of the jet, resulting in a velocity difference between the head and tail of the jet. In addition, the penetration ability parameters of PTFE / AL active jet, such as head velocity and effective jet length, are significantly improved by the third generation explosives, especially CL-20 explosives, and are significantly affected by the charge type, the thickness of the active liner and the cone angle of the liner.
Graphene Composite Modified Manganese Dioxide Cathode Materials for Thermal Batteries
Authors: Shang X M , Wang F , Zhou S F , Shen B , Li Y M , Yan L
Published: December 2024

Limitations on rated voltage and discharge current density pose challenges to battery miniaturisation, affecting their application in missiles and other weapon systems. A modification method of graphene composite manganese dioxide (MnO2) cathode material has been proposed. This method enhances the performance of lithium manganese dioxide thermal batteries (heat activated reserve batteries) by achieving a continuous discharge time from milliseconds to seconds, with a single-cell voltage exceeding 2.6V and a cathode output of 160 mA/cm2. Experimental results indicate that graphene-composite modification improves the output performance of individual lithium manganese dioxide thermal cells and facilitates the reduction of thermal battery design volume. However, further research is necessary to address the relatively low output current density of this thermal battery system.
Fracture toughness of fibre failure modes in laminated composites under dynamic loading
Authors: He Rui , Cheng Longfei , Gao Yidi , Cui Hao , Li Yulong , Liu Jianhu
Published: December 2024

The fracture toughness regarding fibre tensile failure and fibre compression kinking was measured using compact tension and compact compression specimens on a uniaxial bi-directional electromagnetic Hopkinson bar system. During the dynamic tests, the strain/displacement fields were monitored using the digital image correlation technique with a high-speed camera. Digital and scanning electron microscopy were used to investigate the fracture faces of the tested specimens. The initial fracture toughness for fibre tensile failure under quasi-static and dynamic loading was 166 kJ/m2 and 113 kJ/m2, respectively. For fibre compression kinking, the initial fracture toughness was approximately 120 kJ/m2 for both loading conditions. Less fibre pull-out may be responsible for the decrease in fracture toughness for fibre tensile failure under dynamic loading. Whereas for fibre compression kinking failure, there was no significant difference in the fracture faces of the damaged specimens at different loading rates.
Optimization of Heat Treatment Process for the Improvement of Mechanical Properties in Metastable β Titanium Alloy
Authors: Chen Kai , Li Nan , Tao Zhiguo , Li Jishan , Wang Wanpeng , Shen Zhiwei , Wu Di , Pan Hongyun
Published: December 2024

Metastable β-type titanium alloys have garnered significant attention due to their microstructural diversity and excellent mechanical properties. In this study, the metastable β titanium alloy Ti-6Mo-3.5Cr-1Zr was subjected to the optimized heat treatment process. The optimization resulted in simultaneous enhancement of strength and ductility via grain refinement strengthening and transformation induced plasticity during plastic deformation. Furthermore, alloy microstructure analysis was conducted using Scanning Electron Microscope (SEM), Electron Back Scatter Diffraction (EBSD), and Transmission Electron Microscope (TEM) experiments. This work reveals the influence mechanism of solid solution time on the mechanical properties of titanium alloys, which provides theoretical guidance for the subsequent composition design and preparation of high-strength and high-ductility titanium alloys.
An improved LSSVM-based method for prediction demand for maritime logistics support material
Authors: Sun Jianxin , Liu Yuxuan , Tang Haonan , Shen Junyi , Zhang An , Bi Wenhao
Published: December 2024

The primary task of carrier formation maritime logistics support is to supply ammunition, oil, food, water, and other materials to carrier and formation ships at sea, ensuring strong survivability and sustained combat capability. To ensure adequate supplies for maritime missions, the logistics department needs to make an accurate scientific prediction of material consumption before the mission. In this paper, a method for maritime logistics support material demand prediction based on an improved least squares support vector machine is proposed, and the feasibility and accuracy of the method are validated through various arithmetic examples and realistic scenarios, demonstrating its practical applicability and accuracy in predicting material demands.
Research on the Aerodynamic and External Ballistic Characteristics of Bullets Based on Low-Temperature Meteorological Factors
Authors: Zheng Xu , He Liang , Wei Wei , Wang Haosheng
Published: December 2024

To further investigate the aerodynamic and ballistic trajectory characteristics of a certain type of ammunition under the influence of low-temperature meteorological factors, based on computational fluid dynamics and rigid body dynamic trajectory equations, numerical calculations and analysis of the aerodynamic characteristics and 6-degree-of-freedom rigid body ballistic trajectory, as well as low-temperature environmental ballistic trajectory flight tests, were conducted on this type of ammunition. The research shows that under constant atmospheric pressure, as the ambient temperature decreases, the pressure on the bullet surface increases, the aerodynamic parameters of the bullet decrease, and the convergence trend of the bullet’s ballistic trajectory angle of attack weakens significantly; under constant low-temperature, as the atmospheric pressure decreases, the pressure on the bullet surface decreases, the changes in the aerodynamic parameters of the bullet are small, and the convergence trend of the bullet’s ballistic trajectory angle of attack increases.
Stochastic evolution of projectile motion during artillery exterior ballistic
Authors: Mingming Wang , Rongjun Yang , Hongbin Chen , Jinsong Tang
Published: December 2024

In order to analyze the variation law of the flight distance error of the unpowered projectile with time, the probability density function (PDF) of projectile flight distance is calculated by the probability density evolution method (PDEM) based on 6 degrees of freedom rigid ballistic equation with random parameters of the projectile. A test example shows that the calculated results of PDEM are consistent with Monte Carlo (MC) method, which further verifies the effectiveness. In addition, the evolution of projectile flight distance and its error is analyzed within the given ranges of projectile parameter error, which provides a reference for the general design of artillery.
Study on the Beam Section and Joint Configuration of Payload Frame of Special Vehicle
Authors: Zhiwu Yan , Kun Wu , Zhiguang Bao , Hongwei Zhang , Fang Liu , Jiao Zhang , Dehai Wang , Ruoshi Zhao , Yin Zhang
Published: December 2024

With the increasing demand for series of special equipment, light-weight and high-payload capacity along with high mobility have become the major trends in the development of the new generation of special vehicles. The key to achieving high-payload capacity in thin-walled special vehicles lies in the successful application of annular frame beams. This paper focuses on the structural forms of typical annular frames of thin-walled special vehicle, with a particular emphasis on the study of beam cross-sections and beam joint configurations. By applying the Optistruct shape optimization method, improvements to configuration parameters were made to achieve the optimal structural form. A simulation comparison with traditional structural forms was conducted, and the results demonstrate that the new beam cross-section and beam joint configurations can significantly reduce the payload stress level and increase the payload strength while reducing thickness, meeting the high payload characteristic requirements of thin-walled special vehicles.
Influence of head surface conditions of projectiles on initial cavitation and supercavity
Authors: Na Xiaodong , Wang Hao , Huang Zhengui , Hou Yu , Chen Zhihua
Published: December 2024

To investigate the inception of cavitation, the morphology of supercavity, and the detailed flow field influenced by the surface morphology of underwater high-speed projectiles, a high-precision large eddy simulation method was developed. The method accurately simulates cavitation inception and its fine structure under the influence of small-scale changes, enabling the high-precision numerical simulation of the projectile’s supercavitating flow field. The results indicate that the diameter of the cavitator and the height of the rough belt significantly affect the initial cavitation flow field of the projectile. As the cavitator’s diameter decreases, the initial cavitation number of the projectile notably decreases. Compared to conditions without a rough belt, increasing the rough belt alters the distribution of the primary cavity and the flow field structure near the wall. When the rough belt height is minimal, the formation and collapse of the primary cavity occur farther from the projectile’s head and the near-wall region. Introducing a rough zone of appropriate height can increase the pressure in the near-wall flow field and enhance vapor content, thereby promoting cavitation inception. A small rough zone height inhibits cavitation inception, while a large rough zone height promotes it.
The Effect of Doped Diamond Particles on the Mechanical Properties of Tungsten
Authors: Zhu Rui , Chen Lin , Ma Ming-Hui , Wu Yi-Ding , Gao Guang-Fa
Published: December 2024

Tungsten, known for its high strength and excellent heat resistance, finds extensive application in military and industrial fields. However, its brittlenes at room temperature limits its broader use. Dispersion strengthening is one of the effective methods to improve the properties of tungsten and its alloys. This study investigates the dispersion strengthening of tungsten by uniformly distributing fine damond particles (0.5 μm) within the tungsten matrix. Quasi-static and dynamic compression tests were conducted on three types of tungsten materials: pure tungsten (W), tungsten with 0.05% carbon (W-0.05%C), and tungsten with 0.1% carbon (W-0.1%C). The test results demonstrate that, compared to pure tungsten, the tungsten-based composites doped with diamond particles exhibit higher strength and superior plastic deformation capability, along with pronounced work hardening behavior. As the diamond content increases, the strain rate sensitivity and toughness of the materials also increase. Among them, W-0.1%C shows the highest strength and plasticity. The study elucidates the strengthening mechanism of diamond particles within the tungsten matrix, providing scientific guidance for designing new tungsten-based composite materials that combine high strength with good toughness. This research further broadens the application scope of tungsten materials, meeting the higher demands of military and industrial sectors.
An Adaptive Procedure of Time Synchronization in Unstructured Multi-Hop Wireless Sensor Networks using Butterfly Optimization Algorithm
Authors: Abdul-Rashid Ramadan , Abd Rahman Mohd Amiruddin
Published: December 2024

Wireless sensor networks (WSNs) play a pivotal role in various applications, ranging from environmental monitoring to defence technology. This paper proposes a novel time synchronization protocol for WSNs inspired by the Butterfly Optimization algorithm. The time synchronization problem is formulated into an optimization problem for heuristic evolutionary algorithms, and the recently reported Butterfly optimization algorithm is used to optimize clock parameters and carry out global network synchronization. A working protocol is proposed for clock synchronization in multi hop WSN. The proposed protocol is evaluated experimentally against the Newton inspired Time Synchronization protocol and the Average Proportional Integral Synchronization protocol. Experimental results showed better performance in terms of synchronization accuracy as compared to the other protocols.
Fuze dual-channel ballistic height fusion and prediction algorithm based on FCI-KF
Authors: Wu Dan , Zhang Ke , Wang Xin , Xu Ruichen , Yang Jingang
Published: December 2024

To improve the measurement accuracy of the ballistic height and anti-interference ability of fuze in complex environments, the fuze dual-channel ballistic height fusion and prediction algorithm based on Fast Covariance Intersection fusion Kalman Filter (FCI-KF) is proposed. Firstly, the state model and observation model are established, the improved Kalman Filter (KF) algorithm is used to predict the height of the single-channel and then the Fast Covariance Intersection (FCI) algorithm is used to fuse the dual-channel data. This algorithm does not need to calculate the cross-covariance matrix between channels, hence the amount of calculation is small, which is convenient for engineering realization. Finally, the algorithm is simulated and verified, the simulation results show that the measurement accuracy of the proposed algorithm can be significantly improved compared with the original measurement, and the measurement accuracy of the ballistic height is better than that of the traditional methods using only one channel, which verifies the effectiveness of the algorithm.
Numerical Simulation Analysis on Anti-Penetration Characteristics of Al/UHMWPE Composite Plates Against Tungsten Alloy Fragment
Authors: Zhang Xinzhe , Wang Rentao , Hou Huidong , Yu Bin , Li Guoju
Published: December 2024

With the rapid growing demand for armor protection systems that prioritize reduced weight, Al/UHMWPE composite plates have become a promising option in armor protection field. In this work, the finite element model of the Al/UHMWPE composite plates against tungsten alloy fragment was established firstly to investigate the influence of the interfacial strength on the ballistic performance. In addition, both the failure mechanisms and energy-absorbing performance of AI/UHMWPE composite plates were also systematically explored. Numerical simulation results indicate that lower interfacial strength can more accurately simulate the phenomenon of sub-laminates separation under high-speed penetration conditions. The failure mechanisms of Al/UHMWPE composite plates involve sequential processes including deformation of the Al alloy plate, tensile deformation of the UHMWPE laminated plate, fracture of the sub-laminate, and finally, delamination of the UHMWPE laminated plate. Furthermore, the specific energy absorption (SEA) was utilized to quantify the ballistic performance between Al alloy plate and UHMWPE plate, demonstrating that UHMWPE plate significantly dominates, with a capability of 16.4 J/(kg/m2), accounting for 53.4% of total SEA.
Multiple cruise munitions target localisation algorithm based on optimised particle swarm algorithm
Authors: Zhang Chuanhao , Li Haojie , Zhang Lingyun , Qiao Shixiang , Yu Hang , Li Changsheng
Published: December 2024

In the process of locating unknown targets within a target area using multiple cruise munition nodes, it is crucial to achieve precise and rapid target localization through sensor data from multiple munitions. This paper presents a target positioning algorithm based on the Particle Swarm Optimization (PSO) algorithm, which enables cooperative positioning by multiple cruise munitions through the establishment of an appropriate objective function. Simulation results show that while the PSO algorithm offers high positioning accuracy, it can sometimes get trapped in local optima. To address this, the PSO algorithm is optimized by introducing dynamic adaptive weights and integrating Differential Evolution (DE) and Simulated Annealing (SA) algorithms. Comparative simulations demonstrate that the improved PSO algorithm achieves greater accuracy and stability than other optimization algorithms.
Effect of Thermite on Near-ground Explosion Performance of HMX-based Thermobaric Explosive
Authors: Xiao Wei , Zhu Yingzhong , Tang Lei , Yang Zhao , Zou Lang , Bi Xiaolu , Wang Boliang
Published: December 2024

In this paper, the effect and action low of thermite on the explosion performance of HMX-based thermobaric explosive were studied. A series of near-ground explosion were tested for the explosives containing Fe2O3 and CuO. The results showed that thermobaric explosive containing thermite had a significant thermal effect, the peak temper ature was about 15% higher than that of TNT, and the distribution of the fireball morphology and temperature was asymmetrical. Compared with CuO, Fe2O3 could significantly increase incident wave ’s peak overpressure and duration of barotropic action, and Fe2O3 had greater advantages than CuO in promoting thermite reaction to increase fireball temperature and duration of thermal effect. The results provide reference and guidance for the formulation design of thermobaric explosive.
Enhanced process safety: Liquid level identification in the process of preparing PBXs by water suspension method using YOLOV8
Authors: Zhang Zhe , Hao Jingyi , Lv Xijuan , Shang Fengqin , Zou Haoming , Shu Qinghai
Published: December 2024

Realizing online monitoring of the process of preparing Plastic Bonded Explosives (PBXs) by water suspension method has far-reaching significance for optimizing the preparation process, improving product quality, and ensuring personnel safety. The application of deep learning algorithms has significantly improved the efficiency of image recognition and is widely used in various industries. This study proposes a YOLOV8 framework based on deep learning to identify liquid level pictures during the preparation process of PBXs. The data sets are divided according to different split ratios, and each data set uses three levels of epoch of 100, 200 and 300 for training. Four key performance indicators, including precision, recall, mAP50 and mAP50-95, are used to evaluate the quality of the model. The results show that the model has outstanding recognition effect, and all indicators have reached more than 97%. This study innovatively applied the deep learning framework to the field of PBXs preparation, realized the monitoring of the PBXs preparation process, and provided new ideas and foundation for the advanced manufacturing of PBXs.
Shock Activation Mechanism of Aluminum Nano-Particles outside High Explosives
Authors: Zhandong Wang , Fang Chen , Liangliang Zhang , Chuan Xiao
Published: December 2024

Adding aluminum nanoparticles (ANPs) to explosive charges can effectively increase the total explosion energy and work capacity. A novel explosive charge was researched where ANPs were placed outside the high explosive. And the shock activation mechanism for the ANPs was proposed. The proposed shock activation mechanism suggests that under shock loadings, ANPs ignite due to the combined effects of shock work and plastic work. To investigate this mechanism, four turns of explosion experiments were conducted with varying layer thicknesses of ANPs in an enclosed space. The quasi-static pressure was measured to characterize the activation efficiency of the ANPs. The experimental results revealed that the reaction degree of the ANPs ranged from 55.9% to 67.2%, indicating that ANPs reached a relatively high reaction degree despite being placed outside the high explosives. Furthermore, the reaction degree decreased monotonically from 67.2% to 55.9% as the Al layer thickness increased from 1.3% to 6.3% of the explosive diameter. This observation suggests that the activation efficiency of the ANPs decreased with increasing layer thickness. These experimental findings show that the shock activation mechanism can effectively explain the activation of ANPs placed outside of explosives. The proposed shock activation mechanism is indeed valid and provides a promising approach to enhance the explosion energy and work capacity by incorporating ANPs in the charge configuration.