Defence Technology(防务技术)最新文献_第10页

Deformation patterns of steel targets against long rod penetration 钢靶在长杆侵彻下的变形规律

IF 5.9 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2025-08-01 DOI: 10.1016/j.dt.2025.04.017

Chengxin Du , Peng Wang , Bingnan Xing , Feng Zhou , Wenzheng Lv , Zhonghua Du , Guangfa Gao

An experimental and finite element simulation investigation are conducted to study the deformation patterns of steel targets during the penetration process of tungsten alloy long rods, as well as the influence of strength of the target on the deformation patterns. The experimental results revealed slight mass loss in the first layer of the steel target during the transient entrance phase, with an extremely negligible loss in target mass during the quasi-steady penetration phase. The results of macro-analysis, micro-analysis and simulation show that the eroded target material migrated towards the periphery of the crater, causing an increase in the target's thickness, remained within the target, instead of flowing out of the crater. Therefore, the process of long rods penetrating the metal target is considered as a process of backward extrusion. By combining the backward extrusion theory with energy conservation, a penetration depth model for long rods penetrating a metal target, taking into account both the diameter of the crater and the friction coefficient between the rod and the target, has been established. Although the model is not yet perfect, it innovatively applies the principles of solid mechanics to the study of long rod penetration. Additionally, it takes into account the friction coefficient between the rod and the target during the penetration process. Therefore, this model provides a new research direction for future studies on long rod penetration.

通过试验和有限元模拟研究了钨合金长杆侵彻过程中钢靶的变形规律，以及靶强度对变形规律的影响。实验结果表明，在瞬态进入阶段，钢靶第一层的质量损失很小，在准稳定侵彻阶段，目标质量损失几乎可以忽略不计。宏观分析、微观分析和仿真结果表明，被侵蚀的靶材向弹坑外围迁移，导致靶材厚度增加，并没有流出弹坑，而是停留在靶材内部。因此，长杆穿透金属靶的过程被认为是向后挤压的过程。将反向挤压理论与能量守恒理论相结合，建立了考虑弹坑直径和杆与靶间摩擦系数的长杆侵彻金属靶的侵彻深度模型。虽然该模型尚不完善，但它创新地将固体力学原理应用于长杆贯入的研究。此外，它还考虑了钻杆在穿透过程中与目标之间的摩擦系数。因此，该模型为今后的长杆侵彻研究提供了新的研究方向。

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引用次数: 0

A hierarchical simulation framework incorporating full-link physical response for short-range infrared detection 结合全链路物理响应的近程红外探测分层仿真框架

IF 5.9 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2025-08-01 DOI: 10.1016/j.dt.2025.04.013

Mingze Gao , Lixin Xu , Shiyuan Hu , Xiaolong Shi , Jiaming Gao , Yanjiang Wu , Huimin Chen

Missile-borne short-range infrared detection (SIRD) technology is commonly used in military ground target detection. In complex battlefield environments, achieving precise strike on ground target is a challenging task. However, real battlefield data is limited, and equivalent experiments are costly. Currently, there is a lack of comprehensive physical modeling and numerical simulation methods for SIRD. To this end, this study proposes a SIRD simulation framework incorporating full-link physical response, which is integrated through the radiative transfer layer, the sensor response layer, and the model-driven layer. In the radiative transfer layer, a coupled dynamic detection model is established to describe the external optical channel response of the SIRD system by combining the infrared radiation model and the geometric measurement model. In the sensor response layer, considering photoelectric conversion and signal processing, the internal signal response model of the SIRD system is established by a hybrid mode of parametric modeling and analog circuit analysis. In the model-driven layer, a co-simulation application based on a three-dimensional virtual environment is proposed to drive the full-link physical model, and a parallel ray tracing method is employed for real-time synchronous simulation. The proposed simulation framework can provide pixel-level signal output and is verified by the measured data. The evaluation results of the root mean square error (RMSE) and the Pearson correlation coefficient (PCC) show that the simulated data and the measured data achieve good consistency, and the evaluation results of the waveform eigenvalues indicate that the simulated signals exhibit low errors compared to the measured signals. The proposed simulation framework has the potential to acquire large sample datasets of SIRD under various complex battlefield environments and can provide an effective data source for SIRD application research.

弹载近程红外探测技术是军用地面目标探测中常用的一种技术。在复杂的战场环境中，实现对地面目标的精确打击是一项具有挑战性的任务。然而，真实的战场数据是有限的，等效的实验是昂贵的。目前，缺乏全面的SIRD物理建模和数值模拟方法。为此，本研究提出了一个包含全链路物理响应的SIRD仿真框架，该框架通过辐射传输层、传感器响应层和模型驱动层进行集成。在辐射传输层，将红外辐射模型与几何测量模型相结合，建立了描述SIRD系统外部光通道响应的耦合动态检测模型。在传感器响应层，考虑光电转换和信号处理，采用参数化建模和模拟电路分析相结合的方式，建立了SIRD系统内部信号响应模型。在模型驱动层，提出了基于三维虚拟环境的协同仿真应用驱动全链路物理模型，并采用平行光线追踪方法进行实时同步仿真。所提出的仿真框架能够提供像素级的信号输出，并得到了实测数据的验证。均方根误差（RMSE）和Pearson相关系数（PCC）的评估结果表明，模拟信号与实测数据具有较好的一致性，波形特征值的评估结果表明，模拟信号与实测信号相比误差较小。所提出的仿真框架具有获取各种复杂战场环境下SIRD大样本数据集的潜力，可以为SIRD应用研究提供有效的数据源。

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引用次数: 0

Distributed event-triggered control for UAV swarm target fencing with network connectivity preservation and collision avoidance 基于网络连通性和避碰的无人机群目标防护分布式事件触发控制

IF 5.9 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2025-08-01 DOI: 10.1016/j.dt.2025.04.004

Xiuxia Yang, Hao Yu, Yi Zhang, Wenqiang Yao

This paper proposes a distributed event-triggered control (ETC) framework to address cooperative target fencing challenges in UAV swarm. The proposed architecture eliminates the reliance on preset formation parameters while achieving multi-objective cooperative control for target fencing, network connectivity preservation, collision avoidance, and communication efficiency optimization. Firstly, a differential state observer is constructed to obtain the target's unmeasurable states. Secondly, leveraging swarm self-organization principles, a geometric-constraint-free distributed fencing controller is designed by integrating potential field methods with consensus theory. The controller dynamically adjusts inter-UAV distances via single potential function, enabling coordinated optimization of persistent network connectivity and collision-free motion during target fencing. Thirdly, a dual-threshold ETC mechanism based on velocity consensus deviation and fencing error is proposed, which can be triggered based on task features to dynamically adjust the communication frequency, significantly reduce the communication burden and exclude Zeno behavior. Theoretical analysis demonstrates the stability of closed-loop systems. Multi-scenario simulations show that the proposed method can achieve robust fencing under target maneuverability, partial UAV failures, and communication disturbances.

本文提出了一种分布式事件触发控制（ETC）框架，以解决无人机群中的协同目标围栏问题。该体系结构消除了对预设编队参数的依赖，同时实现了目标隔离、网络连通性保持、碰撞避免和通信效率优化等多目标协同控制。首先，构造微分状态观测器获取目标的不可测状态；其次，利用群体自组织原理，将势场方法与共识理论相结合，设计了无几何约束的分布式围栏控制器；该控制器通过单个势函数动态调整无人机间距离，实现目标击穿过程中持久网络连接和无碰撞运动的协调优化。第三，提出了一种基于速度一致性偏差和围栏误差的双阈值ETC机制，该机制可以根据任务特征触发，动态调整通信频率，显著降低通信负担，排除Zeno行为。理论分析证明了闭环系统的稳定性。多场景仿真结果表明，该方法能够在目标机动性、无人机局部故障和通信干扰等条件下实现鲁棒隔离。

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引用次数: 0

Collision-inducing method for UAV evasive maneuvers based on receding horizon optimization 基于后退水平优化的无人机规避机动诱导碰撞方法

IF 5.9 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2025-08-01 DOI: 10.1016/j.dt.2025.04.001

Haonan Tang , Zhigong Tang , Gong Chen , Jifeng Guo

Aiming at the missile avoidance problem of the unmanned aerial vehicle (UAV) in complex obstacle environments, this work proposes a collision-avoidance method based on receding horizon optimization. The proposed method generated a specific trajectory for the UAV to effectively induce the proportional navigation missile to successfully intercept the obstacle, thereby accomplishing the evasive maneuver. The evasive maneuver was divided into two distinct stages, namely the collision-inducing phase and the fast departure phase. The obstacle potential field-based target selection algorithm was employed to identify the most appropriate target obstacle, while the induced trajectory was determined through a combination of receding horizon optimization and the hp-adaptive pseudo-spectral method. Simulation experiments were carried out under three different types of obstacle environments and one multi-obstacle environment, and the simulation results show that the method proposed in this paper greatly improves the success rate of UAV evasive maneuvers, proving the effectiveness of this method.

针对复杂障碍物环境下无人机的导弹避碰问题，提出了一种基于后退视界优化的避碰方法。该方法为无人机生成特定弹道，有效诱导比例导航导弹成功拦截障碍物，从而完成规避机动。将避碰机动分为两个阶段，即碰撞诱导阶段和快速离开阶段。采用基于障碍势场的目标选择算法识别最合适的目标障碍物，结合后退水平优化和hp-自适应伪谱法确定诱导轨迹。在三种不同类型障碍物环境和一种多障碍物环境下进行了仿真实验，仿真结果表明，本文提出的方法大大提高了无人机规避机动的成功率，证明了该方法的有效性。

引用次数: 0

Experimental study on the anti-penetration characteristics of liquid-filled structure with air layer 带空气层充液结构抗侵彻特性的实验研究

IF 5.9 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2025-08-01 DOI: 10.1016/j.dt.2025.03.023

Mengmeng Wu , Jian Jin , Hailiang Hou

The study aims to explore the damage characteristics and protection technologies of liquid-filled structures under high-speed projectile impact. A series of penetration impact experiments were conducted by focusing on different air layer configurations. By using high-speed camera and dynamic measurement systems, the effects of air layers on the projectile penetration, pressure wave propagation, cavitation evolution, and structural dynamic responses were analyzed. The results showed that the rarefaction wave reflected from the air-liquid interface significantly reduced the peak and specific impulse of the initial pressure wave, thereby diminishing the impact load on the structure. Additionally, the compressibility of air layers also attenuated the cavitation extrusion load. Both front and rear plates exhibited superimposed deformation modes, i.e., local deformation or petal fracture with global deformation. Air layers effectively mitigated global deformation. However, when the air layer was positioned on the projectile's trajectory, it split the water-entry process and velocity attenuation of the projectile into two relatively independent phases. And the secondary water entry pressure wave caused more severe local deformation and petal fractures on the rear plate.

本研究旨在探讨充液结构在高速弹丸冲击下的损伤特性及防护技术。针对不同空气层构型，进行了一系列侵彻冲击实验。利用高速摄像和动态测量系统，分析了空气层对弹丸侵彻、压力波传播、空化演化和结构动力响应的影响。结果表明，从气液界面反射的稀薄波显著降低了初始压力波的峰值和比冲，从而减小了对结构的冲击载荷。此外，空气层的可压缩性也减弱了空化挤压载荷。前后板均表现出局部变形或花瓣断裂与整体变形叠加的变形模式。空气层有效地减缓了全球变形。然而，当空气层定位在弹丸的弹道上时，它将弹丸的入水过程和速度衰减分为两个相对独立的阶段。二次进水压力波对后板局部变形和花瓣断裂的影响更为严重。

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引用次数: 0

Response of underwater cylindrical shell subjected to supercavitating projectile trans-medium penetration: Experiment and simulation 超空泡弹丸跨介质侵彻水下圆柱壳的响应：实验与仿真

IF 5.9 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2025-08-01 DOI: 10.1016/j.dt.2025.03.002

Yiming Ma, Kui Tang, Lingquan Kong, Hanxin Gong, Minhui Gu, Chao Cao, Jinxiang Wang

To investigate the dynamic response of the cylindrical shell targets to supercavitating projectile trans-medium penetration and the penetration mechanism, experiments and numerical simulations were conducted. Simulations examined the effects of entry water velocity and impact angle on penetration behavior. The results indicate that, upon water entry, the supercavitating projectile transfers its kinetic energy to the surrounding water medium, causing a sudden rise in local pressure. This creates an approximately hemispherical pressure field in the water medium ahead of the nose of the projectile, where the pressure distribution and magnitude are positively correlated with the velocity of the projectile. As the pressure field approaches the cylindrical shell, the area around the impact point experiences pre-stress and deformation due to the hydrodynamic pressure, which is known as the hydrodynamic ram effect. The deformation of the cylindrical shell caused by the hydrodynamic ram effect increases with increasing velocity of the projectile and exhibits a non-linear relationship with the impact angle, first decreasing and then increasing as the impact angle rises. Additionally, the hydrodynamic ram effect leads to greater local deformation and higher peak stresses in the cylindrical shell, which reduces the penetration drag force faced by the projectile in water compared to air, indicating a lower ballistic limit for underwater targets. During the penetration process, as the impact angle increases, the supercavitating projectile undergoes repetitive bending deformation and even brittle fracture, while the failure mode of the target is characterized by ductile hole expansion. Furthermore, the critical penetration velocity required to perforate the cylindrical shell target increases with increasing impact angle.

为研究超空泡弹跨介质侵彻对圆柱壳靶的动力响应及其侵彻机理，进行了实验和数值模拟。模拟测试了进入水流速和冲击角对侵彻行为的影响。结果表明，超空泡弹丸入水后，将其动能传递给周围的水介质，引起局部压力的突然升高。这在弹鼻前方的水介质中产生了一个近似半球形的压力场，其中压力分布和大小与弹丸的速度呈正相关。当压力场接近圆柱壳时，由于动水压力的作用，冲击点周围的区域发生了预应力和变形，称为动水冲击效应。水动力撞击效应引起的圆柱壳变形随弹丸速度的增大而增大，与冲击角呈先减小后增大的非线性关系。此外，水动力撞击效应导致圆柱壳的局部变形更大，峰值应力更高，这使得弹丸在水中所面临的突防阻力比在空气中要小，这表明水下目标的弹道极限更低。在侵彻过程中，随着冲击角的增大，超空泡弹丸发生反复弯曲变形甚至脆性断裂，靶体的破坏模式以韧性孔洞扩张为特征。此外，随着冲击角的增大，射孔圆柱壳靶所需的临界侵彻速度也随之增大。

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引用次数: 0

Novel optimization techniques for underwater wireless optical communication links: using Monte Carlo simulation 基于蒙特卡罗模拟的水下无线光通信链路优化新技术

IF 5.9 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2025-08-01 DOI: 10.1016/j.dt.2025.04.012

Intesar Ramley , Hamdah M. Alzayed , Yas Al-Hadeethi , Abeer Z. Barasheed , Mingguang Chen

The Underwater Communication Link (UCL) is a crucial component of Underwater Wireless Optical Communication (UWOC) systems, requiring optimised design to mitigate the high power attenuation inherent in seawater. To ensure the reliability of an optimal UCL design, it is essential to account for the three primary scattering regimes: forward scattering (FSC), backward scattering (BSC), and isotropic scattering (ISC) in seawater channels. This study introduces a new photon-tracking model based on a discrete equation, facilitating Monte Carlo Simulation (MCS) to evaluate how different scattering regimes influence received photon distribution. Three distinct Scattering Regime Contribution Weight (SRCW) probability sets were employed, each representing different UCL operational configurations dominated by specific scattering regimes. The proposed modeling approach enables a comprehensive assessment of the temporal characteristics of received optical pulses, channel loss, and time spread—ultimately defining the optimal UCL design parameters. The key findings of this study include: (1) Enhancing the FSC regime dominance leads to a quasi-light waveguide effect over link spans and small Fields of View (FOV) < 25°, significantly improving channel performance in Harbor seawater compared to Coastal seawater. (2) A well-designed UCL with a small FOV (<25°) can minimise channel loss and time spread, ensuring high capacity and efficient performance in both Coastal and Harbor seawaters. (3) When BSC and ISC contributions exceed FSC dominance, the received optical pulse undergoes significant temporal broadening, particularly for larger FOV angles (>25°) and extended link spans. (4) The developed novel MCS-based discrete equation provides a simple yet robust model for simulating photon propagation in both homogeneous and inhomogeneous underwater channels. These insights contribute to developing more efficient and reliable UCL designs with military standards by enhancing UWOC system performance over a longer linkspan for a given limited optical power across various underwater environments.

水下通信链路（UCL）是水下无线光通信（UWOC）系统的关键组成部分，需要优化设计以减轻海水中固有的高功率衰减。为了确保最佳UCL设计的可靠性，必须考虑海水通道中的三种主要散射机制：前向散射（FSC）、后向散射（BSC）和各向同性散射（ISC）。本研究引入了一种新的基于离散方程的光子跟踪模型，便于蒙特卡罗模拟（MCS）评估不同散射机制对接收光子分布的影响。采用三个不同的散射区贡献权重（SRCW）概率集，每个概率集代表由特定散射区主导的不同UCL操作配置。所提出的建模方法能够全面评估接收光脉冲的时间特性、信道损耗和时间扩展，最终确定最佳的UCL设计参数。本研究的主要发现包括：(1)增强FSC体制优势导致在链路跨度和小视场（FOV） <上产生准光波导效应；25°，与沿海海水相比，海港海水显著改善了航道性能。(2)设计良好的UCL具有较小的FOV （<25°），可以最大限度地减少通道损失和时间扩展，确保在沿海和港口海水中的高容量和高效性能。(3)当BSC和ISC的贡献超过FSC的主导地位时，接收到的光脉冲经历了显著的时间展宽，特别是在较大的视场角（>25°）和延长的链路跨度时。(4)基于mcs的离散方程为均匀和非均匀水下通道的光子传播模拟提供了一个简单而稳健的模型。这些见解有助于开发更高效、更可靠的符合军事标准的UCL设计，通过在各种水下环境中给定的有限光功率下提高UWOC系统在更长的链路跨度上的性能。

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引用次数: 0

Fabrication of energetic semiconductor Bridge with high efficiency, accuracy and low cost by 3D direct writing 三维直写技术制备高效率、高精度、低成本的高能半导体桥

IF 5.9 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2025-08-01 DOI: 10.1016/j.dt.2025.04.007

Yongqi Da , Jiangtao Zhang , Fuwei Li , Yuxuan Zhou , Jianbing Xu , Yinghua Ye , Ruiqi Shen

Enhancing the output capacity of semiconductor bridge (SCB) through the application of composite nano-energetic films is a subject of wide concern. Furthermore, improving the safety, reliability, and production efficiency of energetic semiconductor bridge (ESCB) is the primary focus for large-scale engineering applications in the future. Here, the Al/CuO nano-film ESCB was efficiently fabricated using 3D direct writing. The electrostatic safety of the film is enhanced by precisely adjusting the particle size of Al, while ensuring that the SCB can initiate the film with small energy. The burst characteristics of SCB/ESCB were thoroughly investigated by employing a 100 μF tantalum capacitor to induce SCB and ESCB under an intense voltage gradient. The solid-state heating process of both SCB and ESCB was analyzed with multi physical simulation (MPS). The experimental results demonstrate that the critical burst time of both SCB and ESCB decreases with increasing voltage. Under the same voltage, the critical burst time of ESCB is longer than that of SCB, primarily due to differences in the melting to vaporization stage. The MPS results indicate that the highest temperature is observed at the V-shaped corner of SCB. Due to the thermal contact resistance between SCB and the film, heat conduction becomes more concentrated in the central region of the bridge, resulting in a faster solid-state heating process for ESCB compared to SCB. The results of the gap ignition experiments indicate that at a 19 mm gap, an ESCB with a film mass of 10 mg can ignite nickel hydrazine nitrate (NHN) and cyclotrimethylenetrinitramine (RDX). This suggests that thermite ESCB can serve as a novel, safe, and reliable energy exchange element and initiator in large-scale engineering applications.

利用复合纳米能膜提高半导体电桥的输出能力是一个受到广泛关注的课题。此外，提高高能半导体桥（ESCB）的安全性、可靠性和生产效率是未来大规模工程应用的主要焦点。本文采用三维直写技术制备了Al/CuO纳米薄膜ESCB。通过精确调节Al的粒径，提高了膜的静电安全性，同时保证SCB能以小能量引发膜。采用100 μF钽电容在强电压梯度下诱导SCB和ESCB，深入研究了SCB/ESCB的爆发特性。采用多物理模拟（MPS）对SCB和ESCB的固态加热过程进行了分析。实验结果表明，SCB和ESCB的临界爆发时间都随电压的升高而减小。在相同电压下，ESCB的临界爆裂时间比SCB的长，这主要是由于熔化到汽化阶段不同。MPS结果表明，在SCB的v形角处温度最高。由于SCB与薄膜之间存在热接触阻，热传导更加集中在桥的中心区域，导致ESCB的固态加热过程比SCB更快。间隙点火实验结果表明，膜质量为10 mg的ESCB在19 mm间隙下可以点燃硝酸肼镍（NHN）和环三甲基三胺（RDX）。这表明铝热剂ESCB在大规模工程应用中可以作为一种新型、安全、可靠的能量交换元件和引发剂。

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引用次数: 0

Safety assessment of framed hot launch departure for sea-based rockets in rough sea conditions 恶劣海况下海基火箭框架热发射离场安全评价

IF 5.9 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2025-08-01 DOI: 10.1016/j.dt.2025.03.017

Deng Wang , Jianshuai Shao , Nan Cao , Yi Jiang , Tong Huang

Sea-based rocket launches encounter significant challenges stemming from dynamic marine environmental interactions. During the hot launch phase, characterized by low-velocity ascent, the departure of the rocket from the oscillatory platform exhibits heightened sensitivity to external disturbances. In the development stage, assessing the launch dynamics and the clearance between the rocket and framed launcher are crucial for improving the reliability of sea-based rocket launches in rough sea conditions. This study presents a high-fidelity dynamic model of maritime hot launch system, demonstrating 3.21% prediction error through rigorous validation against experimental datasets from comprehensive modal analyses and the full-scale rocket flight test. To mitigate collision risks, we develop a computational method employing spatial vector analysis for dynamic measurement of rocket-launcher clearance during departure. Systematic investigations reveal that in rough sea conditions, optimal departure dynamics are achieved at θ_thrust = 270° nozzle azimuth configuration, reducing failure probability compared to conventional orientations. The developed assessment framework not only resolves critical safety challenges in current sea launch systems but also establishes foundational principles for optimizing adapter axial configuration patterns in future designs.

海基火箭发射面临着来自动态海洋环境相互作用的重大挑战。在以低速上升为特征的热发射阶段，火箭离开振荡平台对外部干扰表现出高度的敏感性。在研制阶段，评估发射动力学和火箭与框架发射器之间的间隙对提高海基火箭在恶劣海况下发射的可靠性至关重要。本文建立了海上热发射系统的高保真动态模型，通过综合模态分析和全尺寸火箭飞行试验数据的严格验证，预测误差为3.21%。为了降低碰撞风险，我们开发了一种使用空间矢量分析的计算方法来动态测量火箭发射器在起飞过程中的间隙。系统研究表明，在恶劣的海况下，θ推力= 270°喷嘴方位配置可以实现最佳的偏离动力学，与常规定向相比，降低了失效概率。开发的评估框架不仅解决了当前海上发射系统的关键安全挑战，而且为未来设计中优化适配器轴向配置模式建立了基本原则。

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引用次数: 0

Bimetallic MOF (Mn/Co) constructed by active dicyandiamide linker for a promising combustion catalyst of solid propellant 活性双氰胺连接剂构建的双金属MOF （Mn/Co）是一种很有前途的固体推进剂燃烧催化剂

IF 5.9 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2025-08-01 DOI: 10.1016/j.dt.2025.04.005

Mingcheng Ge , Xian Xu , Ze Su , Ye Zhong , Binfang Yuan , Huisheng Huang , Jianguo Zhang , Zhimin Li

Combustion catalyst is a key modifier for the performance of composite solid propellant. To exploit high-efficiency combustion catalyst, a fascinating bimetallic metal-organic framework [MnCo(EIM)₂(DCA)₂]_n (1) was constructed by an active dicyandiamide (DCA) linker, Mn²⁺, Co²⁺ centers, and an 1-ethylimidazole (EIM) ligand. 1 possesses good thermal stability (T_p = 205 °C), high energy density (E_g = 24.34 kJ/g, E_v = 35.93 kJ/cm³), and insensitivity to impact and frictional stimulus. The catalytic effects of 1 contrasted to monometallic coordination compounds Mn(EIM)₄(DCA)₂ (2) and Co(EIM)₄(DCA)₂ (3) on the thermal decomposition of AP/RDX composite were investigated by a DSC method. The decomposition peak temperatures of AP and RDX of the composite decreased to 335.8 °C and 206.4 °C, respectively, and the corresponding activation energy decreased by 27.3% and 43.6%, respectively, which are better than the performances of monometallic complexes 2 and 3. The gas products in the whole thermal decomposition stage of the sample were measured by TG-MS and TG-IR, and the catalytic mechanism of 1 to AP/RDX was further analyzed. This work reveal potential application of bimetallic MOFs in the composite solid propellants.

燃烧催化剂是影响复合固体推进剂性能的关键改性剂。为了开发高效的燃烧催化剂，以活性双氰胺（DCA）连接剂、Mn2+、Co2+中心和1-乙基咪唑（EIM）配体为原料，构建了一种令人瞩目的双金属金属有机骨架[MnCo(EIM)2(DCA)2]n(1)。1热稳定性好（Tp = 205℃），能量密度高（Eg = 24.34 kJ/g, Ev = 35.93 kJ/cm3），对冲击和摩擦刺激不敏感。采用DSC法考察了1与单金属配位化合物Mn(EIM)4(DCA)2(2)和Co(EIM)4(DCA)2(3)对AP/RDX复合材料热分解的催化作用。复合材料AP和RDX的分解峰温度分别降至335.8℃和206.4℃，对应的活化能分别下降27.3%和43.6%，性能优于单金属配合物2和3。采用TG-MS和TG-IR对样品整个热分解阶段的气体产物进行了测定，并进一步分析了1对AP/RDX的催化机理。本工作揭示了双金属MOFs在复合固体推进剂中的潜在应用。

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