Defence Technology(防务技术)最新文献_第5页

Influences of muzzle jets of aircraft guns on aerodynamic performance of wings 机炮炮口射流对机翼气动性能的影响

IF 5.9 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2026-01-01 DOI: 10.1016/j.dt.2025.08.001

Zijie Li, Hao Wang

The core components of an aircraft and the source of its lift are its wings, but lift generation is disrupted by the high temperature and pressure generated on the wing surface when an aircraft gun is fired. Here, to investigate how this process influences the aerodynamic parameters of aircraft wings, the k–ω shear-stress-transport turbulence model and the nested dynamic grid technique are used to analyze numerically the transient process of the muzzle jet of a 30-mm small-caliber aircraft gun in high-altitude (10 km) flight with an incoming Mach number of Ma = 0.8. For comparison, two other models are established, one with no projectile and the other with no wing. The results indicate that when the aircraft gun is fired, the muzzle jet acts on the wing, creating a pressure field thereon. The uneven distribution of high pressure greatly reduces the lift of the aircraft, causing oscillations in its drag and disrupting its dynamic balance, thereby affecting its flight speed and attitude. Meanwhile, the muzzle jet is obstructed by the wing, and its flow field is distorted and deformed, developing upward toward the wing. Because of the influence of the incoming flow, the shockwave front of the projectile changes from a smooth spherical shape to an irregular one, and the motion parameters of the projectile are also greatly affected by oscillations. The present results provide an important theoretical basis for how the guns of fighter aircraft influence the aerodynamic performance of the wings.

飞机的核心部件和升力的来源是机翼，但当飞机射击时，机翼表面产生的高温和高压会破坏升力的产生。为了研究这一过程对飞机机翼气动参数的影响，采用k -ω剪切应力传递湍流模型和嵌套动态网格技术，对30毫米小口径机炮在10公里高空（10公里）来流马赫数Ma = 0.8条件下的炮口射流瞬态过程进行了数值分析。为了进行比较，分别建立了无弹和无翼两种模型。结果表明，飞机炮发射时，枪口射流作用在机翼上，在机翼上形成压力场。高压的不均匀分布大大降低了飞机的升力，引起飞机阻力振荡，破坏飞机的动平衡，从而影响飞机的飞行速度和姿态。同时，枪口射流受到机翼的阻挡，流场发生扭曲变形，向机翼方向向上发展。由于来流的影响，弹丸的激波前由光滑的球形变为不规则的球形，弹丸的运动参数也受到振荡的很大影响。研究结果为研究机炮对机翼气动性能的影响提供了重要的理论依据。

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引用次数: 0

Microstructures and mechanical properties of friction stir welded and processed high entropy alloys 搅拌摩擦焊接和加工高熵合金的组织和力学性能

IF 5.9 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2026-01-01 DOI: 10.1016/j.dt.2025.08.002

Kang Chen , Jian Miao , Huijie Zhang , Qi Cheng , Yingling Wang

High entropy alloys (HEAs) have recently attracted significant attention due to their exceptional mechanical properties and potential applications across various fields. Friction stir welding and processing (FSW/P), as notable solid-state welding and processing techniques, have been proved effectiveness in enhancing microstructures and mechanical properties of HEAs. This review article summarizes the current status of FSW/P of HEAs. The welding materials and conditions used for FSW/P in HEAs are reviewed and discussed. The effects of FSW/P on the evolutions of grain structure, texture, dislocation, and secondary phase for different HEAs are highlighted. Furthermore, the influences of FSW/P on the mechanical properties of various HEAs are analyzed. Finally, potential applications, challenges, and future directions of FSW/P in HEAs are forecasted. Overall, FSW/P enable to refine grains of HEAs through dynamic recrystallization and to activate diverse deformation mechanisms of HEAs through tailoring phase structures, thereby significantly improving the strength, hardness, and ductility of both single- and dual-phase HEAs. Future progress in this field will rely on comprehensive optimization of processing parameters and alloy composition, integration of multi-scale modeling with advanced characterization for in-depth exploration of microstructural mechanisms, systematic evaluation of functional properties, and effective bridging of the gap between laboratory research and industrial application. The review aims to provide an overview of recent advancements in the FSW/P of HEAs and encourage further research in this area.

高熵合金（HEAs）由于其优异的力学性能和在各个领域的潜在应用，近年来引起了广泛的关注。搅拌摩擦焊接与加工（FSW/P）是一种显著的固态焊接与加工技术，在改善HEAs的组织和力学性能方面具有显著的效果。本文综述了高等学校固体废物处理技术的研究现状。综述和讨论了高强度焊接系统中FSW/P的焊接材料和焊接条件。重点研究了FSW/P对不同HEAs晶粒组织、织构、位错和次生相演变的影响。进一步分析了FSW/P对不同HEAs力学性能的影响。最后，展望了FSW/P在高等教育系统中的潜在应用、面临的挑战和未来发展方向。总体而言，FSW/P能够通过动态再结晶细化HEAs的晶粒，并通过定制相结构激活HEAs的多种变形机制，从而显著提高单相和双相HEAs的强度、硬度和延展性。该领域未来的发展将依赖于工艺参数和合金成分的综合优化，多尺度建模与先进表征相结合，深入探索微观组织机制，系统评估功能特性，有效弥合实验室研究与工业应用之间的差距。本文旨在概述高等教育机构的固体废物/废物处理的最新进展，并鼓励在这一领域进行进一步的研究。

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引用次数: 0

Magnetic pulse welding of Al-5754 with Al-7075 and MARS 380: Weldability windows and ballistic testing Al-5754与Al-7075和MARS 380的磁脉冲焊接：可焊性窗口和弹道试验

IF 5.9 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2026-01-01 DOI: 10.1016/j.dt.2025.07.024

Benoit Lagain , Thomas Heuzé , Guillaume Racineux , Michel Arrigoni

Joining dissimilar materials encounters significant engineering challenges due to the contrast in material properties that makes conventional welding not feasible. Magnetic Pulse Welding (MPW) offers a solid-state joining technique that overcomes these issues by using impact to create strong bonds without melting the substrate materials. This study investigates the weldability of aluminum alloy Al-5754 with Al-7075 and MARS 380 steel, used in armouring solutions of defense systems, by the use of MPW. In this work, weldability windows are investigated by varying standoff distances between the coating material and its substrate (0.25–4.5 mm) and discharge energies (5–13 kJ) with both O-shape and U-shape inductors. Mechanical strength of the welded joints were assessed through single lap shear tests, identifying optimal welding parameters. Then, the velocity profiles of the flyer plates were measured using heterodyne velocimetry to understand the dynamics of the impact. Then, substructures assembled with the optimal welding conditions were subjected to ballistic testing using 7.62 mm × 51 mm NATO and 9 mm × 19 mm Parabellum munitions to evaluate the resilience of the welds under ballistic impact. The outcomes demonstrate that MPW effectively joins Al-5754 with both Al-7075 and MARS 380, producing robust welds capable of withstanding ballistic impacts under certain conditions. This research advances the application of MPW in lightweight ballistic protection of defense systems, contributing to the development of more resilient and lighter protective structures.

由于材料特性的差异，使得传统焊接不可行，因此连接不同材料遇到了重大的工程挑战。磁脉冲焊接（MPW）提供了一种固态连接技术，通过使用冲击来建立牢固的结合，而不会熔化基板材料，从而克服了这些问题。本文研究了用于国防系统装甲溶液的Al-5754铝合金与Al-7075和MARS 380钢的焊接性能。在这项工作中，通过改变涂层材料与衬底之间的距离（0.25-4.5 mm）和放电能量（5-13 kJ），研究了o形和u形电感的可焊性窗口。通过单次搭接剪切试验评估焊接接头的机械强度，确定最佳焊接参数。然后，利用外差测速仪测量了飞片的速度分布，以了解撞击动力学。然后，采用7.62 mm × 51 mm NATO和9 mm × 19 mm Parabellum弹药对最佳焊接条件下组装的子结构进行弹道试验，评估焊缝在弹道冲击下的回弹性。结果表明，MPW有效地将Al-5754与Al-7075和MARS 380结合在一起，产生了能够承受一定条件下弹道冲击的坚固焊缝。该研究促进了MPW在国防系统轻量化弹道防护中的应用，有助于开发更具弹性和更轻量化的防护结构。

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引用次数: 0

Gyroid-structured SiOC composite with excellent broadband microwave absorption and load-bearing performance 具有良好宽带微波吸收和承载性能的陀螺结构SiOC复合材料

IF 5.9 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2026-01-01 DOI: 10.1016/j.dt.2025.07.026

Hanjun Wei , Siyu Chen , Zhiyong Chen , Lu Tang , Jimei Xue , Cunxian Wang , Zhijun Wang , Ying Li

Designing materials with both structural load-bearing capacity and broadband electromagnetic (EM) wave absorption properties remains a significant challenge. In this work, SiOC/SiC/SiO₂ composite with gyroid structures were prepared through digital light processing (DLP) 3D printing, polymer-derived ceramics (PDCs), chemical vapor infiltration (CVI), and oxidation technologies. The incorporation of the CVI SiC phase effectively increases the dissipation capability, while the synergistic interaction between the gyroid structure and SiO₂ phase significantly improves impedance matching performance. The SiOC/SiC/SiO₂ composite achieved a minimum reflection loss (RL_min) of −62.2 dB at 4.3 mm, and the effective absorption bandwidth (EAB) covered the X-band, with a thickness range of 4.1 mm–4.65 mm. The CST simulation results explain the broadband and low-frequency absorption characteristics, with an EAB of 8.4 GHz (9.6–18 GHz) and an RL_min of −21.5 dB at 5 GHz. The excellent EM wave attenuation performance is associated primarily with polarization loss, conduction loss, the gyroid structure's enhancement of multiple reflections and scattering of EM waves, and the resonance effect between the structural units. The SiOC/SiC/SiO₂ composite also demonstrated strong mechanical properties, with a maximum compressive failure strength of 31.6 MPa in the height direction. This work opens novel prospects for the development of multifunctional structural wave-absorbing materials suitable for broadband microwave absorption and load-bearing properties.

设计既具有结构承载能力又具有宽带电磁波吸收性能的材料仍然是一个重大挑战。本研究通过数字光处理（DLP）、3D打印、聚合物衍生陶瓷（PDCs）、化学蒸汽渗透（CVI）和氧化技术制备了具有陀螺结构的SiOC/SiC/SiO2复合材料。CVI SiC相的加入有效地提高了器件的耗散能力，而陀螺结构与SiO2相的协同作用则显著提高了器件的阻抗匹配性能。SiOC/SiC/SiO2复合材料在4.3 mm处的最小反射损耗（RLmin）为−62.2 dB，有效吸收带宽（EAB）覆盖x波段，厚度范围为4.1 mm - 4.65 mm。CST模拟结果解释了宽带和低频吸收特性，EAB为8.4 GHz (9.6-18 GHz)， RLmin为- 21.5 dB。优异的电磁波衰减性能主要与极化损耗、传导损耗、陀螺结构对电磁波多次反射和散射的增强以及结构单元之间的共振效应有关。SiOC/SiC/SiO2复合材料表现出较强的力学性能，在高度方向上最大抗压破坏强度为31.6 MPa。这项工作为开发适合宽带微波吸收和承载性能的多功能结构吸波材料开辟了新的前景。

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引用次数: 0

Enhancing polyvinyl alcohol (PVA) nanocomposites: Key properties, applications and challenges in advanced engineering 增强聚乙烯醇（PVA）纳米复合材料：关键性能、在先进工程中的应用和挑战

IF 5.9 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2026-01-01 DOI: 10.1016/j.dt.2025.05.020

Azrol Jailani , M. Hazim Hidzer , A.H.M. Firdaus , S.M. Sapuan , Edi Syams Zainudin , Afdzaluddin Atiqah , Wan Munira Wan Jaafar , Lisman Suryanegara

This review highlights the performance enhancement of polyvinyl alcohol (PVA) composites through the incorporation of nanofillers, focusing on mechanical, thermal, electrical and piezoelectric improvements. It examines bio-based fillers such as nanocellulose cellulose nanofibrils (CNF) and cellulose nanocrystals (CNC), and carbon-based fillers like graphene nanoplatelets (GNP) and carbon nanotubes (CNT). CNF and CNC increase tensile strength by up to 40% and 17.9%, respectively, due to their ability to reinforce polymer networks. CNC also improves thermal stability, raising degradation temperatures to approximately 327 °C through enhanced hydrogen bonding. Electrical and piezoelectric properties are significantly improved, with dielectric behaviour enhanced by up to 107% and open-circuit voltage reaching 25.6 V, suitable for energy harvesting. GNP and CNT contribute by forming conductive networks within the PVA matrix, enabling superior electrical conductivity and consistent piezoresistive responses under strain. These characteristics make such composites ideal for applications in flexible electronics, sensors, structural health monitoring and other advanced fields. This synthesis of experimental results and critical insights underscores the broad utility and future potential of nanofiller-enhanced PVA composites across aerospace, automotive, healthcare, and defence sectors.

本文综述了纳米填料对聚乙烯醇（PVA）复合材料性能的增强，重点是力学、热学、电学和压电性能的改进。它研究了生物基填料，如纳米纤维素纳米原纤维（CNF）和纤维素纳米晶体（CNC），以及碳基填料，如石墨烯纳米片（GNP）和碳纳米管（CNT）。CNF和CNC的抗拉强度分别提高了40%和17.9%，这是由于它们增强聚合物网络的能力。CNC还提高了热稳定性，通过增强氢键将降解温度提高到约327°C。电学和压电性能显著提高，介电性能提高高达107%，开路电压达到25.6 V，适合能量收集。GNP和碳纳米管通过在PVA矩阵内形成导电网络，从而实现卓越的导电性和应变下一致的压阻响应。这些特性使这种复合材料非常适合应用于柔性电子、传感器、结构健康监测和其他先进领域。这一实验结果和关键见解的综合强调了纳米填料增强PVA复合材料在航空航天、汽车、医疗保健和国防领域的广泛应用和未来潜力。

{"title":"Enhancing polyvinyl alcohol (PVA) nanocomposites: Key properties, applications and challenges in advanced engineering","authors":"Azrol Jailani , M. Hazim Hidzer , A.H.M. Firdaus , S.M. Sapuan , Edi Syams Zainudin , Afdzaluddin Atiqah , Wan Munira Wan Jaafar , Lisman Suryanegara","doi":"10.1016/j.dt.2025.05.020","DOIUrl":"10.1016/j.dt.2025.05.020","url":null,"abstract":"<div><div>This review highlights the performance enhancement of polyvinyl alcohol (PVA) composites through the incorporation of nanofillers, focusing on mechanical, thermal, electrical and piezoelectric improvements. It examines bio-based fillers such as nanocellulose cellulose nanofibrils (CNF) and cellulose nanocrystals (CNC), and carbon-based fillers like graphene nanoplatelets (GNP) and carbon nanotubes (CNT). CNF and CNC increase tensile strength by up to 40% and 17.9%, respectively, due to their ability to reinforce polymer networks. CNC also improves thermal stability, raising degradation temperatures to approximately 327 °C through enhanced hydrogen bonding. Electrical and piezoelectric properties are significantly improved, with dielectric behaviour enhanced by up to 107% and open-circuit voltage reaching 25.6 V, suitable for energy harvesting. GNP and CNT contribute by forming conductive networks within the PVA matrix, enabling superior electrical conductivity and consistent piezoresistive responses under strain. These characteristics make such composites ideal for applications in flexible electronics, sensors, structural health monitoring and other advanced fields. This synthesis of experimental results and critical insights underscores the broad utility and future potential of nanofiller-enhanced PVA composites across aerospace, automotive, healthcare, and defence sectors.</div></div>","PeriodicalId":58209,"journal":{"name":"Defence Technology(防务技术)","volume":"55 ","pages":"Pages 11-29"},"PeriodicalIF":5.9,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145981908","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

3D printed high-temperature ceramic conformal array antenna: Design, analysis, manufacturing, and testing 3D打印高温陶瓷共形阵列天线：设计、分析、制造和测试

IF 5.9 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2026-01-01 DOI: 10.1016/j.dt.2025.05.012

Peng Li , Ruibo Li , Zijiao Fan , Jiujiu Han , Guangda Ding , Qunbiao Wang , Wanye Xu , Paolo Rocca

In this study, the design, analysis, manufacturing, and testing of a 3D-printed conformal microstrip array antenna for high-temperature environments is presented. 3D printing technology is used to fabricate a curved ceramic substrate, and laser sintering and microdroplet spraying processes are used to add the conductive metal on the curved substrate. The problems of gain loss, bandwidth reduction, and frequency shift caused by high temperatures are addressed by using a proper antenna design, with parasitic patches, slots, and metal resonant cavities. The antenna prototype is characterized by the curved substrates and the conductive metals for the power dividers, the patch, and the ground plane; its performance is examined up to a temperature of 600 °C in a muffle furnace and compared with the results from the numerical analysis. The results show that the antenna can effectively function at 600 °C and even higher temperatures.

在本研究中，介绍了用于高温环境的3d打印共形微带阵列天线的设计、分析、制造和测试。采用3D打印技术制备弯曲陶瓷基板，采用激光烧结和微滴喷涂工艺在弯曲基板上添加导电金属。采用适当的天线设计，采用寄生贴片、槽和金属谐振腔，解决了高温引起的增益损失、带宽降低和频移问题。天线原型的特点是：弯曲基板和用于功率分压器、贴片和接地面的导电金属；在温度高达600℃的马弗炉中测试了其性能，并与数值分析结果进行了比较。结果表明，该天线可以在600℃甚至更高的温度下有效工作。

引用次数: 0

Acoustic physics-informed intelligent path planning framework for active sonar search 基于声物理的主动声纳搜索智能路径规划框架

IF 5.9 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2026-01-01 DOI: 10.1016/j.dt.2025.08.008

Siyuan Liao, Wenbin Xiao, Yongxian Wang, Zhao Sun, Houwang Tu, Wenfeng Liu

In underwater target search path planning, the accuracy of sonar models directly dictates the accurate assessment of search coverage. In contrast to physics-informed sonar models, traditional geometric sonar models fail to accurately characterize the complex influence of marine environments. To overcome these challenges, we propose an acoustic physics-informed intelligent path planning framework for underwater target search, integrating three core modules: The acoustic-physical modeling module adopts 3D ray-tracing theory and the active sonar equation to construct a physics-driven sonar detection model, explicitly accounting for environmental factors that influence sonar performance across heterogeneous spaces. The hybrid parallel computing module adopts a message passing interface (MPI)/open multi-processing (OpenMP) hybrid strategy for large-scale acoustic simulations, combining computational domain decomposition and physics-intensive task acceleration. The search path optimization module adopts the covariance matrix adaptation evolution algorithm to solve continuous optimization problems of heading angles, which ensures maximum search coverage for targets. Large-scale experiments conducted in the Pacific and Atlantic Oceans demonstrate the framework's effectiveness: (1) Precise capture of sonar detection range variations from 5.45 km to 50 km in heterogeneous marine environments. (2) Significant speedup of 453.43 × for acoustic physics modeling through hybrid parallelization. (3) Notable improvements of 7.23% in detection coverage and 15.86% reduction in optimization time compared to the optimal baseline method. The framework provides a robust solution for underwater search missions in complex marine environments.

在水下目标搜索路径规划中，声纳模型的精度直接决定着搜索范围的准确评估。与物理声纳模型相比，传统的几何声纳模型无法准确表征海洋环境的复杂影响。为了克服这些挑战，我们提出了一个基于声学物理的水下目标搜索智能路径规划框架，集成了三个核心模块：声学物理建模模块采用3D光线追踪理论和主动声纳方程来构建物理驱动的声纳探测模型，明确考虑了影响声纳在异构空间中性能的环境因素。混合并行计算模块采用消息传递接口(MPI)/开放多处理（OpenMP）混合策略进行大规模声学模拟，将计算域分解和物理密集型任务加速相结合。搜索路径优化模块采用协方差矩阵自适应进化算法求解航向角的连续优化问题，保证了对目标的最大搜索覆盖率。在太平洋和大西洋进行的大规模实验证明了该框架的有效性：(1)在非均匀海洋环境中精确捕获声纳探测距离从5.45 km到50 km的变化。(2)混合并行化可显著提高声学物理建模速度453.43倍。(3)与最优基线方法相比，检测覆盖率提高了7.23%，优化时间缩短了15.86%。该框架为复杂海洋环境下的水下搜索任务提供了强大的解决方案。

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引用次数: 0

Detonation characteristics of the solid-liquid mixed fuel cloud of Al/B/MgH2/DEE/IPN Al/B/MgH2/DEE/IPN固液混合燃料云爆轰特性

IF 5.9 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2026-01-01 DOI: 10.1016/j.dt.2025.08.004

Zhangjun Wu , Xianzhao Song , Shuxin Deng , Bingbing Yu , Yongxu Wang , Rhoda Afriyie Mensah , Suning Mei

To elucidate the dispersion and explosion characteristics of multi-metal powder and liquid composite fuel formulations, high-energy metal powders (aluminum (Al), boron (B), and magnesium hydride (MgH₂)) are incorporated into a liquid fuel primarily composed of diethyl ether (DEE) and isopropyl nitrate (IPN). The explosion characteristics of different solid-liquid fuel-air-explosive (FAE) under unconfined conditions are investigated using a high-speed camera, infrared thermal imaging, and a pressure measurement system. Results demonstrate that high-energy metal powders significantly enhance detonation energy dissipation, with aluminum exhibiting the most pronounced effect. Fuel 5# (45.4 wt% DEE, 9.2 wt% IPN, 29.5 wt% Al, 9.1 wt% B, 6.8 wt% MgH₂) exhibits superior explosion performance, achieving higher values of overpressure, impulse, and thermal radiation damage during the detonation stage compared to other fuels. However, Fuel 5# also displays faster decay rates, attributed to accelerated heat release rates induced by B and MgH₂ powders. This study reveals that different metal powders in solid-liquid FAE exhibit distinct enhancements in explosion performance, providing critical insights for optimizing composite fuel design.

为了阐明多金属粉末和液体复合燃料配方的分散和爆炸特性，将高能金属粉末(铝（Al）、硼（B)和氢化镁（MgH2））掺入主要由乙醚（DEE）和硝酸异丙基（IPN）组成的液体燃料中。采用高速摄像机、红外热成像和压力测量系统研究了不同固液燃料-空气炸药（FAE）在无侧限条件下的爆炸特性。结果表明，高能金属粉末能显著提高爆轰能量耗散，其中铝粉的效果最为显著。5#燃料（45.4 wt% DEE, 9.2 wt% IPN, 29.5 wt% Al, 9.1 wt% B, 6.8 wt% MgH2）表现出优异的爆炸性能，与其他燃料相比，在爆轰阶段实现了更高的超压、脉冲和热辐射损伤值。然而，燃料5#也显示出更快的衰变速率，这归因于B和MgH2粉末引起的加速热释放速率。该研究表明，不同的金属粉末在固液FAE中表现出不同的爆炸性能增强，为优化复合燃料设计提供了重要的见解。

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引用次数: 0

Long-range masked autoencoder for pre-extraction of trajectory features in within-visual-range maneuver recognition 视距内机动识别中弹道特征预提取的远程掩码自编码器

IF 5.9 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2026-01-01 DOI: 10.1016/j.dt.2025.07.020

Feilong Jiang, Hutao Cui, Yuqing Li, Minqiang Xu, Rixin Wang

In the field of intelligent air combat, real-time and accurate recognition of within-visual-range (WVR) maneuver actions serves as the foundational cornerstone for constructing autonomous decision-making systems. However, existing methods face two major challenges: traditional feature engineering suffers from insufficient effective dimensionality in the feature space due to kinematic coupling, making it difficult to distinguish essential differences between maneuvers, while end-to-end deep learning models lack controllability in implicit feature learning and fail to model high-order long-range temporal dependencies. This paper proposes a trajectory feature pre-extraction method based on a Long-range Masked Autoencoder (LMAE), incorporating three key innovations: (1) Random Fragment High-ratio Masking (RFH-Mask), which enforces the model to learn long-range temporal correlations by masking 80% of trajectory data while retaining continuous fragments; (2) Kalman Filter-Guided Objective Function (KFG-OF), integrating trajectory continuity constraints to align the feature space with kinematic principles; and (3) Two-stage Decoupled Architecture, enabling efficient and controllable feature learning through unsupervised pre-training and frozen-feature transfer. Experimental results demonstrate that LMAE significantly improves the average recognition accuracy for 20-class maneuvers compared to traditional end-to-end models, while significantly accelerating convergence speed. The contributions of this work lie in: introducing high-masking-rate autoencoders into low-information-density trajectory analysis, proposing a feature engineering framework with enhanced controllability and efficiency, and providing a novel technical pathway for intelligent air combat decision-making systems.

在智能空战领域，对视距内机动动作的实时准确识别是构建自主决策系统的基础。然而，现有的方法面临两大挑战：传统的特征工程由于运动耦合导致特征空间有效维数不足，难以区分动作之间的本质差异；端到端深度学习模型在隐式特征学习中缺乏可控制性，无法对高阶长时间依赖关系进行建模。本文提出了一种基于远程掩码自编码器（LMAE）的轨迹特征预提取方法，其中包含三个关键创新：(1)随机片段高比率掩蔽（RFH-Mask），该方法通过在保留连续片段的同时掩蔽80%的轨迹数据来强制模型学习远程时间相关性；(2)卡尔曼滤波制导目标函数（KFG-OF），整合轨迹连续性约束，使特征空间与运动学原理对齐；(3)两阶段解耦架构，通过无监督预训练和冻结特征转移实现高效可控的特征学习。实验结果表明，与传统的端到端模型相比，LMAE显著提高了20类机动的平均识别精度，同时显著加快了收敛速度。本文的贡献在于：将高掩码率的自编码器引入到低信息密度的轨迹分析中，提出了一种增强可控性和效率的特征工程框架，为智能空战决策系统提供了新的技术途径。

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引用次数: 0

Dynamic fracture behavior and coupled impact effect of as-cast W-Zr-Ti energetic structural material 铸态W-Zr-Ti含能结构材料的动态断裂行为及耦合冲击效应

IF 5.9 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2026-01-01 DOI: 10.1016/j.dt.2025.07.025

Yuxuan Qi , Liang Mao , Chunlan Jiang , Guitao Liu , Kongxun Zhao , Mengchen Zhang

This paper prepared a novel as-cast W-Zr-Ti metallic ESM using high-frequency vacuum induction melting technique. The above ESM performs a typical elastic-brittle material feature and strain rate strengthening behavior. The specimens exhibit violent chemical reaction during the fracture process under the impact loading, and the size distribution of their residual debris follows Rosin-Rammler model. The dynamic fracture toughness is obtained by the fitting of debris length scale, approximately 1.87 MPa·m^1/2. Microstructure observation on residual debris indicates that the failure process is determined by primary crack propagation under quasi-static compression, while it is affected by multiple cracks propagation in both particle and matrix in the case of dynamic impact. Impact test demonstrates that the novel energetic fragment performs brilliant penetration and combustion effect behind the front target, leading to the effective ignition of fuel tank. For the brittleness of as-cast W-Zr-Ti ESM, further study conducted bond-based peridynamic (BB-PD) C++ computational code to simulate its fracture behavior during penetration. The BB-PD method successfully captured the fracture process and debris cloud formation of the energetic fragment. This paper explores a novel as-cast metallic ESM, and provides an available numerical avenue to the simulation of brittle energetic fragment.

本文利用高频真空感应熔炼技术制备了一种新型铸态W-Zr-Ti金属ESM。上述ESM表现出典型的弹脆材料特征和应变率强化行为。试件在冲击载荷作用下断裂过程中表现出剧烈的化学反应，残余碎屑的尺寸分布符合Rosin-Rammler模型。通过碎片长度尺度拟合得到动态断裂韧性，约为1.87 MPa·m1/2。对残屑的微观组织观察表明，准静态压缩下的破坏过程由原生裂纹扩展决定，动态冲击下的破坏过程受颗粒和基体多重裂纹扩展的影响。冲击试验表明，新型高能破片在前靶后具有优异的侵彻和燃烧效果，使燃料箱有效点火。针对铸态W-Zr-Ti ESM的脆性，进一步研究了基于bond-based periddynamic (BB-PD) c++计算程序，模拟了其穿透过程中的断裂行为。BB-PD方法成功捕获了高能碎片的断裂过程和碎片云的形成。本文探索了一种新型铸态金属ESM，为脆性含能破片的数值模拟提供了一条可行的数值途径。

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引用次数: 0