Defence Technology(防务技术)最新文献_第6页

Multi-energy field coupling analysis and experimental validation of picosecond laser drilling assisted by ultrasonic shock-induced water flow 超声激波诱导水流辅助皮秒激光打孔的多能场耦合分析及实验验证

IF 5.9 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2026-01-01 DOI: 10.1016/j.dt.2025.09.002

Pengfei Ouyang , Yang Liu , Zhaoyang Zhang , Xiaolei Chen , Yufeng Wang , Hao Zhu , Kun Xu , Jingtao Wang , Xiankai Meng , Shu Huang

The latest generation of aero engines has set higher standards for thrust-to-weight ratio and energy conversion efficiency, making it imperative to address the challenge of efficiently and accurately machining film cooling holes. It has been demonstrated that conventional long-pulse lasers are incapable of meeting the elevated quality surface finish requirements for these holes, a consequence of the severe thermal defects. The employment of backside water-assisted laser drilling technology confers a number of distinct advantages in terms of mitigating laser thermal damage, thus representing a highly promising solution to this challenge. However, significant accumulation of bubbles and machining products during the backside water-assisted laser drilling process has been demonstrated to have a detrimental effect on laser transmission and machining stability, thereby reducing machining quality. In order to surmount these challenges, a novel method has been proposed, namely an ultrasonic shock water flow-assisted picosecond laser drilling technique. Numerical models for ultrasonic acoustic streaming and particle tracking for machining product transport have been established to investigate the mechanism. The simulation results demonstrated that the majority of the machining products could rapidly move away from the machining area because of the action of acoustic streaming, thereby avoiding the accumulation of bubbles and products. Subsequent analysis, comparing the process performance in micro-hole machining, confirmed that the ultrasonic field could effectively eliminate bubble and chip accumulation, thus significantly improving micro-hole quality. Furthermore, the impact of ultrasonic and laser parameters on micro-hole quality under varying machining methods was thoroughly investigated. The findings demonstrated that the novel methodology outlined in this study yielded superior-quality micro-holes at elevated ultrasonic and laser power levels, in conjunction with reduced laser frequency and scanning velocity. The taper of the micro-holes produced by the new method was reduced by more than 25% compared with the other conventional methods.

最新一代的航空发动机对推重比和能量转换效率提出了更高的标准，解决高效、准确加工膜冷却孔的挑战势在必行。研究表明，由于严重的热缺陷，传统的长脉冲激光无法满足这些孔的高质量表面光洁度要求。采用后向水辅助激光钻井技术在减轻激光热损伤方面具有许多明显的优势，因此是解决这一挑战的一个非常有前途的解决方案。然而，在背面水辅助激光钻孔过程中，气泡和加工产物的大量积累已经被证明对激光传输和加工稳定性有不利影响，从而降低了加工质量。为了克服这些挑战，提出了一种新的方法，即超声激波水流辅助皮秒激光打孔技术。建立了加工产品输运过程中超声声流和颗粒跟踪的数值模型，对其机理进行了研究。仿真结果表明，在声流的作用下，大多数加工产品能够迅速远离加工区域，从而避免了气泡和产品的积累。随后的分析对比了微孔加工的工艺性能，证实超声场可以有效地消除气泡和切屑堆积，从而显著提高微孔质量。进一步研究了不同加工方法下超声和激光参数对微孔质量的影响。研究结果表明，在提高超声波和激光功率水平、降低激光频率和扫描速度的情况下，本研究中概述的新方法产生了高质量的微孔。与其他常规方法相比，新方法制备的微孔锥度减小了25%以上。

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引用次数: 0

Design and experimental validation of a low-impact wing locking/release mechanism based on energy conversion strategy 基于能量转换策略的低冲击机翼锁/释放机构设计与实验验证

IF 5.9 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2026-01-01 DOI: 10.1016/j.dt.2025.10.003

Yanbing Wang , Honghao Yue , Jun Wu , Xueting Pan , Fei Yang , Yong Zhao , Jicheng Liu , Xue Bai

Conventional locking/release mechanisms often face challenges in aircraft wing separation processes, such as excessive impact loads and insufficient synchronization. These may cause structural damage to the airframe or attitude instability, seriously compromising mission reliability. To address this engineering challenge, this paper proposes a multi-point low-impact locking/release mechanism based on the mobility model and energy conversion strategy. Through establishing a DOF constraint framework system, this paper systematically analyzes the energy transfer and conversion characteristics during the wing separation process, reveals the generation mechanism of impact loads, and conducts research on low-impact design based on energy conversion strategy. Building on this foundation, a single-point locking/release mechanism employing parallel trapezoidal key shaft structure was designed, which increases frictional contact time and reduces the energy release rate, thereby achieving low-impact characteristics. The mechanism's performance was validated through physical prototype development and systematic functional testing (including unlocking force, synchronization, and impact tests). Experimental results demonstrate: (1) Under 14 kN preload condition, the maximum unlocking force was only 92.54 N, showing a linear relationship with preload that satisfies the "strong-connection/weak-unlock" design requirement; (2) Wing separation was completed within 46 ms, with synchronization time difference among three separation mechanisms stably controlled within 12–14 ms, proving rapid and reliable operation; (3) The unlocking impact acceleration ranged between 26 and 73 g, below the 100 g design limit, confirming the effectiveness of the energy conversion strategy. The proposed low-impact locking/release mechanism design method based on energy conversion strategy resolves the traditional challenges of high impact and synchronization deficiencies. The synergistic optimization mechanism of "structural load reduction and performance improvement" provides a highly reliable technical solution for wing separable mechanisms while offering novel design insights for wing connection/separation systems engineering.

在飞机机翼分离过程中，传统的锁定/释放机构经常面临冲击载荷过大和同步不足等挑战。这些可能导致机体结构损坏或姿态不稳定，严重损害任务可靠性。为了解决这一工程挑战，本文提出了一种基于移动性模型和能量转换策略的多点低冲击锁定/释放机制。本文通过建立自由度约束框架体系，系统分析了机翼分离过程中的能量传递与转换特性，揭示了冲击载荷的产生机理，并开展了基于能量转换策略的低冲击设计研究。在此基础上，设计了采用平行梯形键轴结构的单点锁/释放机构，增加了摩擦接触时间，降低了能量释放率，实现了低冲击特性。通过物理样机开发和系统功能测试（包括解锁力、同步和冲击测试）验证了该机构的性能。实验结果表明：(1)在14 kN预紧力条件下，最大解锁力仅为92.54 N，与预紧力呈线性关系，满足“强连接/弱解锁”设计要求；(2)翼式分离在46 ms内完成，三种分离机构同步时间差稳定控制在12-14 ms内，运行快速可靠；(3)解锁冲击加速度在26 ~ 73 g之间，低于100 g的设计限值，证实了能量转换策略的有效性。提出了基于能量转换策略的低冲击锁/释放机构设计方法，解决了传统锁/释放机构高冲击和同步不足的问题。“结构减载和性能提升”的协同优化机制为机翼可分离机构提供了高度可靠的技术解决方案，同时为机翼连接/分离系统工程提供了新的设计见解。

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引用次数: 0

Retaining local chemical effects: An error cancellation strategy for calculating standard gas-phase enthalpy of formation 保留局部化学效应：计算标准气相生成焓的误差消除策略

IF 5.9 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2026-01-01 DOI: 10.1016/j.dt.2025.07.028

Rui Liu , Chaoyang Zhang , Linyuan Wang , Zhiyu Huang , Jian Liu

Conventional error cancellation approaches separate molecules into smaller fragments and sum the errors of all fragments to counteract the overall computational error of the parent molecules. However, these approaches may be ineffective for systems with strong localized chemical effects, as fragmenting specific substructures into simpler chemical bonds can introduce additional errors instead of mitigating them. To address this issue, we propose the Substructure-Preserved Connection-Based Hierarchy (SCBH), a method that automatically identifies and freezes substructures with significant local chemical effects prior to molecular fragmentation. The SCBH is validated by the gas-phase enthalpy of formation calculation of CHNO molecules. Therein, based on the atomization scheme, the reference and test values are derived at the levels of Gaussian-4 (G4) and M062X/6-31+G(2df, p), respectively. Compared to commonly used approaches, SCBH reduces the average computational error by half and requires only 15% of the computational cost of G4 to achieve comparable accuracy. Since different types of local effect structures have differentiated influences on gas-phase enthalpy of formation, substituents with strong electronic effects should be retained preferentially. SCBH can be readily extended to diverse classes of organic compounds. Its workflow and source code allow flexible customization of molecular moieties, including azide, carboxyl, trinitromethyl, phenyl, and others. This strategy facilitates accurate, rapid, and automated computations and corrections, making it well-suited for high-throughput molecular screening and dataset construction for gas-phase enthalpy of formation.

传统的误差抵消方法是将分子分成更小的片段，并将所有片段的误差相加，以抵消母体分子的总体计算误差。然而，这些方法对于具有强局部化学效应的系统可能是无效的，因为将特定的子结构分割成更简单的化学键可能会引入额外的错误，而不是减轻它们。为了解决这个问题，我们提出了基于子结构保存连接的层次结构（SCBH），这是一种在分子断裂之前自动识别和冻结具有显著局部化学效应的子结构的方法。通过计算CHNO分子的气相生成焓，验证了SCBH的有效性。其中，基于雾化方案，分别在Gaussian-4 （G4）和M062X/6-31+G（2df, p）水平上推导了参考值和测试值。与常用的方法相比，SCBH将平均计算误差降低了一半，并且只需要G4计算成本的15%就可以达到相当的精度。由于不同类型的局部效应结构对气相生成焓的影响不同，因此应优先保留电子效应强的取代基。SCBH可以很容易地扩展到不同类别的有机化合物。它的工作流程和源代码允许灵活地定制分子部分，包括叠氮化物、羧基、三硝基甲基、苯基等。该策略有助于准确、快速和自动化的计算和校正，使其非常适合于高通量分子筛选和气相生成焓数据集的构建。

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引用次数: 0

Optimized fiber allocation for enhanced impact resistance in composites through damage mode suppression 通过损伤模式抑制，优化纤维分配以增强复合材料的抗冲击性能

IF 5.9 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2026-01-01 DOI: 10.1016/j.dt.2025.05.022

Noha M. Hassan , Zied Bahroun , Mahmoud I. Awad , Rami As'ad , El-Cheikh Amer Kaiss

Variable stiffness composites present a promising solution for mitigating impact loads via varying the fiber volume fraction layer-wise, thereby adjusting the panel's stiffness. Since each layer of the composite may be affected by a different failure mode, the optimal fiber volume fraction to suppress damage initiation and evolution is different across the layers. This research examines how re-allocating the fibers layer-wise enhances the composites' impact resistance. In this study, constant stiffness panels with the same fiber volume fraction throughout the layers are compared to variable stiffness ones by varying volume fraction layer-wise. A method is established that utilizes numerical analysis coupled with optimization techniques to determine the optimal fiber volume fraction in both scenarios. Three different reinforcement fibers (Kevlar, carbon, and glass) embedded in epoxy resin were studied. Panels were manufactured and tested under various loading conditions to validate results. Kevlar reinforcement revealed the highest tensile toughness, followed by carbon and then glass fibers. Varying reinforcement volume fraction significantly influences failure modes. Higher fractions lead to matrix cracking and debonding, while lower fractions result in more fiber breakage. The optimal volume fraction for maximizing fiber breakage energy is around 45%, whereas it is about 90% for matrix cracking and debonding. A drop tower test was used to examine the composite structure's behavior under low-velocity impact, confirming the superiority of Kevlar-reinforced composites with variable stiffness. Conversely, glass-reinforced composites with constant stiffness revealed the lowest performance with the highest deflection. Across all reinforcement materials, the variable stiffness structure consistently outperformed its constant stiffness counterpart.

变刚度复合材料是一种很有前途的解决方案，通过改变纤维体积分数来减轻冲击载荷，从而调整面板的刚度。由于复合材料的每一层都可能受到不同的破坏模式的影响，因此抑制损伤发生和演化的最佳纤维体积分数在各层之间是不同的。本研究探讨了如何重新分配纤维层，以提高复合材料的抗冲击性。在本研究中，将具有相同纤维体积分数的恒定刚度面板与具有不同纤维体积分数的变刚度面板进行了层间比较。建立了一种利用数值分析与优化技术相结合的方法来确定两种情况下的最佳纤维体积分数。研究了三种不同的增强纤维（凯夫拉纤维、碳纤维和玻璃纤维）嵌入环氧树脂中。制作了面板，并在各种加载条件下进行了测试，以验证结果。凯夫拉纤维的拉伸韧性最高，其次是碳纤维，然后是玻璃纤维。不同的配筋体积分数对破坏模式有显著影响。高分数导致基体开裂和脱粘，低分数导致纤维断裂。使纤维断裂能量最大化的最佳体积分数约为45%，而使基体开裂和脱粘的最佳体积分数约为90%。通过跌落塔试验研究了复合材料结构在低速冲击下的性能，验证了变刚度凯夫拉增强复合材料的优越性。相反，恒刚度玻璃增强复合材料的挠度最大，性能最差。在所有增强材料中，变刚度结构始终优于其恒定刚度对应物。

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引用次数: 0

Energy absorption characteristics of additively manufactured sea sponge-inspired lattice structures under low-velocity impact loading 低速冲击载荷下增材制造海棉晶格结构的吸能特性

IF 5.9 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2026-01-01 DOI: 10.1016/j.dt.2025.04.008

J Jefferson Andrew , Jabir Ubaid , Mohammed Ayaz Uddin , Omar Waqas Saadi , Kamran Ahmed Khan , Rehan Umer , Andreas Schiffer

Low-velocity impact tests are carried out to explore the energy absorption characteristics of bio-inspired lattices, mimicking the architecture of the marine sponge organism Euplectella aspergillum. These sea sponge-inspired lattice structures feature a square-grid 2D lattice with double diagonal bracings and are additively manufactured via digital light processing (DLP). The collapse strength and energy absorption capacity of sea sponge lattice structures are evaluated under various impact conditions and are compared to those of their constituent square-grid and double diagonal lattices. This study demonstrates that sea sponge lattices can achieve an 11-fold increase in energy absorption compared to the square-grid lattice, due to the stabilizing effect of the double diagonal bracings prompting the structure to collapse layer-by-layer under impact. By adjusting the thickness ratio in the sea sponge lattice, up to 76.7% increment in energy absorption is attained. It is also shown that sea-sponge lattices outperform well-established energy-absorbing materials of equal weight, such as hexagonal honeycombs, confirming their significant potential for impact mitigation. Additionally, this research highlights the enhancements in energy absorption achieved by adding a small amount (0.015 phr) of Multi-Walled Carbon Nanotubes (MWCNTs) to the photocurable resin, thus unlocking new possibilities for the design of innovative lightweight structures with multifunctional attributes.

模拟海洋海绵生物曲霉Euplectella aspergillum的结构，进行了低速冲击试验，探索仿生晶格的能量吸收特性。这些受海绵启发的晶格结构具有双对角线支撑的方形网格二维晶格，并通过数字光处理（DLP）进行增材制造。评价了海绵晶格结构在各种冲击条件下的抗塌强度和吸能能力，并与其组成方网格和双对角网格结构进行了比较。本研究表明，由于双对角线支撑的稳定作用促使结构在冲击下一层一层地坍塌，海绵晶格的能量吸收比正方形网格增加了11倍。通过调整海绵晶格的厚度比，可使吸能增加76.7%。研究还表明，海绵晶格的性能优于同等重量的公认吸能材料，如六边形蜂窝，这证实了它们在减轻冲击方面的巨大潜力。此外，本研究强调了通过在光固化树脂中添加少量（0.015 phr）的多壁碳纳米管（MWCNTs）来增强能量吸收，从而为设计具有多功能属性的创新轻质结构提供了新的可能性。

{"title":"Energy absorption characteristics of additively manufactured sea sponge-inspired lattice structures under low-velocity impact loading","authors":"J Jefferson Andrew , Jabir Ubaid , Mohammed Ayaz Uddin , Omar Waqas Saadi , Kamran Ahmed Khan , Rehan Umer , Andreas Schiffer","doi":"10.1016/j.dt.2025.04.008","DOIUrl":"10.1016/j.dt.2025.04.008","url":null,"abstract":"<div><div>Low-velocity impact tests are carried out to explore the energy absorption characteristics of bio-inspired lattices, mimicking the architecture of the marine sponge organism <em>Euplectella aspergillum</em>. These sea sponge-inspired lattice structures feature a square-grid 2D lattice with double diagonal bracings and are additively manufactured via digital light processing (DLP). The collapse strength and energy absorption capacity of sea sponge lattice structures are evaluated under various impact conditions and are compared to those of their constituent square-grid and double diagonal lattices. This study demonstrates that sea sponge lattices can achieve an 11-fold increase in energy absorption compared to the square-grid lattice, due to the stabilizing effect of the double diagonal bracings prompting the structure to collapse layer-by-layer under impact. By adjusting the thickness ratio in the sea sponge lattice, up to 76.7% increment in energy absorption is attained. It is also shown that sea-sponge lattices outperform well-established energy-absorbing materials of equal weight, such as hexagonal honeycombs, confirming their significant potential for impact mitigation. Additionally, this research highlights the enhancements in energy absorption achieved by adding a small amount (0.015 phr) of Multi-Walled Carbon Nanotubes (MWCNTs) to the photocurable resin, thus unlocking new possibilities for the design of innovative lightweight structures with multifunctional attributes.</div></div>","PeriodicalId":58209,"journal":{"name":"Defence Technology(防务技术)","volume":"55 ","pages":"Pages 118-129"},"PeriodicalIF":5.9,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145981931","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

Cross-attention spatial–temporal convolutional neural network for energy expenditure estimation on the basis of physical fitness characteristics 基于体能特征的跨注意时空卷积神经网络能量消耗估计

IF 5.9 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2025-12-01 DOI: 10.1016/j.dt.2025.06.009

Qiurui Wang, Fengshun Wang, Yuting Wang, Shanjun Li

Energy expenditure estimation can be used to measure the exercise load and physical condition of different individuals, such as soldiers, athletes, firemen, etc., during their training and work. Energy expenditure estimation methods based on computer vision have rapidly developed in recent years. Compared with sensor-based methods, such methods are capable of monitoring several target persons at the same time, and the subjects do not need to wear different sensor devices that hamper their movement. In this paper, we propose a cross-attention spatial–temporal convolutional neural network to predict the energy expenditure of people under different exercise intensities. The model explores the relationship between changes in the human skeleton and energy expenditure intensity. In addition, a cross-attention correction module is used to reduce the negative effects of individual physical fitness characteristics during energy expenditure estimation. The experimental results show that our proposed method achieves high accuracy for energy expenditure estimation and performs better than existing computer vision-based energy expenditure estimation methods do. The proposed method can be widely used in various physical activity scenarios to measure energy expenditure, increasing the convenience of usage.

能量消耗估算可以用来衡量不同个体，如士兵、运动员、消防员等在训练和工作过程中的运动负荷和身体状况。近年来，基于计算机视觉的能量消耗估算方法得到了迅速发展。与基于传感器的方法相比，这种方法能够同时监测多个目标人员，并且受试者不需要佩戴不同的传感器设备，从而阻碍其运动。在本文中，我们提出了一个跨注意时空卷积神经网络来预测不同运动强度下人们的能量消耗。该模型探讨了人体骨骼变化与能量消耗强度之间的关系。此外，为了减少能量消耗估算过程中个体体质特征的负面影响，采用了交叉注意校正模块。实验结果表明，该方法具有较高的能量消耗估计精度，优于现有的基于计算机视觉的能量消耗估计方法。该方法可广泛应用于各种体力活动场景中测量能量消耗，增加了使用的方便性。

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引用次数: 0

Influence of the buckling degree on the separation properties of clutch friction components 屈曲度对离合器摩擦元件分离性能的影响

IF 5.9 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2025-12-01 DOI: 10.1016/j.dt.2025.07.019

Qin Zhao , Biao Ma , Liang Yu , Dingge Zhang , Liangjie Zheng , Yi Dong

Armored vehicles, to accomplish missions in complex harsh conditions with high mobility, require the transmission system to achieve high energy density and high reliability. The wet multi-disc clutch becomes the perishable component under heavy load, large speed difference, and frequent engagement. Due to the difficulty of maintenance in battlefield, clutch carrying post-buckling separate plate is common, and the clutch working process is obstructed. Therefore, considering the post-buckling plate, the multi-physics thermodynamic model of a wet multi-disc clutch is established to describe the entire engagement and separation process. The influence of the buckling degree on the stress-strain, uniformity of gaps, torque, and temperature characteristics is investigated by the numerical method and testified by bench tests. The results show that with the increasing buckling degree, the clutch engagement and separation times decrease gradually. For the separation process, the non-uniformity of gaps is increased, and gaps are eventually occupied, leading to the continuous rough contact among friction pairs. Therefore, the drag torque is increased. Squeezed by the post-buckling plate, the cooling rates of separate plates are decreased. During repeated engagement-separation, temperatures of plates may reach balance points. Since continuous sliding and temperature concentration, the wear form and degree changes, especially at outer radius. Extra drag torque, heat, and wear threats the friction components which increases the risk of failures of the transmission system and affects the mobility of armored vehicles.

装甲车辆要完成复杂恶劣条件下的高机动任务，对传动系统提出了高能量密度和高可靠性的要求。湿式多片离合器在重载、大转速差和频繁啮合下成为易损部件。由于战场维修困难，离合器携带后屈曲分离片的现象普遍存在，阻碍了离合器的工作过程。因此，考虑后屈曲板，建立了湿式多片离合器的多物理场热力学模型来描述整个接合和分离过程。采用数值方法研究了屈曲程度对应力应变、间隙均匀性、扭矩和温度特性的影响，并通过台架试验进行了验证。结果表明，随着屈曲程度的增加，离合器的接合次数和分离次数逐渐减少。在分离过程中，增加了间隙的不均匀性，最终占据了间隙，导致摩擦副之间持续的粗糙接触。因此，阻力扭矩增大。受后屈曲板的挤压，分离板的冷却速率降低。在重复的接合分离过程中，板的温度可能达到平衡点。由于连续滑动和温度集中，磨损形式和程度发生了变化，尤其是在外半径处。额外的阻力、扭矩、热量和磨损威胁着摩擦部件，增加了传动系统失效的风险，影响了装甲车辆的机动性。

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引用次数: 0

Progress in characterization of interface structure and properties in polymer bonded explosives 聚合物粘结炸药界面结构与性能表征的研究进展

IF 5.9 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2025-12-01 DOI: 10.1016/j.dt.2025.07.015

Chengcheng Zeng, Conmei Lin, Zhijian Yang, Guansong He, Shengjun Zheng, Feiyan Gong, Fude Nie

The precise characterization of interfacial structure for polymer-bonded explosive (PBX) modification is challenging due to the complexity of the interface. The inherent properties between explosive and binders affect interface bonding, lowering the interfacial strength in unpredicted ways. Surface modification is an effective method to balance multi-utility in materials engineering, which has been carried out to design of high-performance composites with improved interfacial properties. Experimental methods may determine the coating shell for capturing the PBX structures. Various approaches were applied to characterize the structure and properties of PBX interface, including molecular dynamics-based computational models to predict bonding properties. In this review, systematic organization were provided and summarized with detective methods on the surface and interface of explosives. Meanwhile, the usage scenarios and limitations of each measurement were proposed. Conclusions from the review yield useful guidelines and references for systematical characterization on the modification of explosive and can be extended to other materials.

由于界面的复杂性，精确表征聚合物粘合炸药（PBX）改性的界面结构具有挑战性。炸药和粘结剂之间的固有性质影响界面粘合，以不可预测的方式降低界面强度。表面改性是材料工程中平衡多种用途的有效方法，已被用于设计具有改善界面性能的高性能复合材料。实验方法可以确定捕获PBX结构的涂层外壳。各种方法被用于表征PBX界面的结构和性质，包括基于分子动力学的计算模型来预测键合性质。本文对爆炸物表面和界面探测方法进行了系统的组织和总结。同时，提出了各种测量方法的使用场景和局限性。所得结论为炸药改性的系统表征提供了有用的指导和参考，并可推广到其他材料。

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引用次数: 0

Damage mechanisms from low-velocity penetrating shrapnel in ballistic gelatin 弹道明胶中低速穿透弹片的损伤机制

IF 5.9 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2025-12-01 DOI: 10.1016/j.dt.2025.07.008

Tesfaye O. Terefe, Anoop Chawla, Naresh V. Datla

Shrapnel projectiles from low-velocity weapons often cause perforations and thereby result in multiple wounds. As shrapnel penetrates, its kinetic energy dissipates and generates forces that influence the extent of damage. However, quantifying these forces and understanding the mechanics of tissue damage remain challenging. To address this, there is a need to measure time-varying forces that will provide critical insights into the mechanics of damage initiation and progression. In this study, a new experimental methodology was developed using a custom-designed fixture integrated with a low-velocity gas gun to study shrapnel-induced damage in ballistic gelatin. The fixture was equipped with piezoelectric sensors to capture transmitted force (TF), while a high-speed camera recorded the damage morphology. The maximum TF response varied significantly, ranging from 45 to 225 N for chisel-nose shrapnel and 75–295 N for blunt-nose shrapnel, across incident velocities of 25–100 m/s. The damage mechanisms, characterized by the formation of temporary cavities, resulted in cavity sizes three to four times larger than the shrapnel diameter. The maximum energy absorbed by the ballistic gelatin was 14.81 J at 92.10 m/s for chisel-nose and 18.50 J at 98.35 m/s for blunt-nose shrapnel. A finite element (FE) model was developed and validated against experimental results with an error margin of less than 15% in the maximum value of TF. This methodology provides a platform for further studies on soft tissue damage by correlating dynamic force measurements with damage mechanisms. These insights can inform advancements in battlefield injury assessment, medical interventions strategies, and the design of protective materials to mitigate shrapnel injuries.

低速武器的弹片通常会造成弹孔，从而造成多处伤口。当弹片穿透时，它的动能消散并产生影响损伤程度的力。然而，量化这些力量和了解组织损伤的机制仍然具有挑战性。为了解决这个问题，我们需要测量随时间变化的力，这将为损伤发生和发展的机制提供关键的见解。在这项研究中，开发了一种新的实验方法，使用定制设计的夹具集成低速气枪来研究弹片引起的弹道明胶损伤。夹具配备了压电传感器来捕捉传递力（TF），同时高速摄像机记录了损伤形态。当入射速度为25-100 m/s时，最大TF响应变化显著，凿鼻弹片在45 - 225 N之间，钝鼻弹片在75-295 N之间。损伤机制以形成临时空腔为特征，导致空腔尺寸比弹片直径大三到四倍。凿鼻弹和钝鼻弹分别以92.10 m/s和98.35 m/s的速度吸收了14.81 J和18.50 J的最大能量。建立了有限元模型，并与实验结果进行了对比验证，得到了小于15%的误差范围。该方法通过将动态力测量与损伤机制相关联，为进一步研究软组织损伤提供了平台。这些见解可以为战场伤害评估、医疗干预策略和防护材料设计提供信息，以减轻弹片伤害。

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引用次数: 0

Adiabatic shear behavior of pearlitic heat-resistant steel under fragment-simulating projectile impact 珠光体耐热钢在破片模拟弹丸冲击下的绝热剪切行为

IF 5.9 Q1 ENGINEERING, MULTIDISCIPLINARY

Defence Technology(防务技术)

Pub Date : 2025-12-01 DOI: 10.1016/j.dt.2025.07.014

Kunxuan Wang , Yubo Gao , Wencai Sun , Wei Zheng , Wenbo Xie

Adiabatic shear band (ASB), as the precursor to catastrophic material failure, is of great significance in the research of impact resistance. This study investigated the adiabatic shear behavior of 12Cr1MoV steel under high-velocity impact from fragment-simulating projectile (FSP) using high-speed impact tests, numerical simulations, and scanning electron microscopy. The results demonstrated that the flat and wedge-shaped segments of the FSP experience different stress conditions and temperature fields during penetration. The asymmetry of the projectile has a pronounced effect on the morphology of the ASB. Two major failure modes were identified during the penetration process: tensile failure and shear failure, with pearlite exhibiting strengthening effects under both loading conditions. The ASB developed distinct microstructural characteristics with increasing impact velocity, exhibiting apparent sensitivity to temperatures and strain rates. Finally, the investigation of the ASB branches revealed the mechanisms underlying ASB formation and the initiation of catastrophic cracking.

绝热剪切带（ASB）作为材料灾难性破坏的前兆，在抗冲击性能研究中具有重要意义。采用高速冲击试验、数值模拟和扫描电镜等方法研究了12Cr1MoV钢在碎片模拟弹丸（FSP）高速冲击下的绝热剪切行为。结果表明，在渗透过程中，FSP的平面段和楔形段经历了不同的应力条件和温度场。弹丸的不对称性对ASB的形态有明显的影响。在渗透过程中确定了两种主要的破坏模式：拉伸破坏和剪切破坏，珠光体在两种加载条件下都表现出强化作用。随着冲击速度的增加，ASB呈现出明显的微观结构特征，对温度和应变速率表现出明显的敏感性。最后，对ASB分支的研究揭示了ASB形成和灾难性开裂的机制。

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