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Enhanced structural damage behavior of liquid-filled tank by reactive material projectile impact

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Defence Technology（防务技术） 2024年第1期31卷 211-229页

作者： Jianwen Xie Yuanfeng Zheng Zhenyang Liu chengzhe Liu Aoxin Liu pengwan chen Haifu Wang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

A series of ballistic experiments were performed to investigate the damage behavior of high velocity reactive material projectiles(RMPs) impacting liquid-filled tanks,and the corresponding hydrodynamic ram(HRAM) was studied in ***/Al/W RMPs with steel-like and aluminum-like densities were prepared by a pressing/sintering *** projectiles impacted a liquid-filled steel tank with front aluminum panel at approximately 1250 m/*** corresponding cavity evolution characteristics and HRAM pressure were recorded by high-speed camera and pressure acquisition system,and further compared to those of steel and aluminum *** different from the conical cavity formed by the inert metal projectile,the cavity formed by the RMP appeared as an ellipsoid with a conical *** RMPs were demonstrated to enhance the radial growth velocity of cavity,the global HRAM pressure amplitude and the front panel damage,indicating the enhanced HRAM and structural damage ***,combining the impact-induced fragmentation and deflagration characteristics,the cavity evolution of RMPs under the combined effect of kinetic energy impact and chemical energy release was *** mechanism of enhanced HRAM pressure induced by the RMPs was further revealed based on the theoretical model of the initial impact wave and the impulse ***,the linear correlation between the deformation-thickness ratio and the non-dimensional impulse for the front panel was obtained and *** was determined that the enhanced near-field impulse induced by the RMPs was the dominant reason for the enhanced structural damage behavior.

关键词： Reactive material projectile Hydrodynamic ram Enhanced structural damage Liquid-filled tank Impact

Formation behaviors of rod-like reactive shaped charge penetrator and their effects on damage capability

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Defence Technology（防务技术） 2024年第2期32卷 242-253页

作者： Tao Sun Haifu Wang Shipeng Wang Chao Ge Die Hu pengwan chen Yuanfeng Zheng Beijing Institute of Technology State Key Laboratory of Explosion Science and TechnologyBeijing100081China Xi'an Institute of Electromechanical Information Technology Xi'an710065China

Formation behaviors of rod-like reactive shaped charge penetrator(RRSCP)and their effects on damage capability are investigated by experiments and numerical *** pulsed X-ray technology and a spaced aluminum/steel plate with the thicknesses of 5 mm/100 mm are *** types of sphericalsegment aluminum-polytetrafluoroethylene-copper(Al-PTFE-Cu)reactive liners with Cu contents of 0%,46.6%,and 66%are fabricated and *** experimental results show that the reactive liners can form excellent rod-shaped penetrators with tail skirts under the shaped charge effect,but the tail skirts disappear over ***,rupturing damage to the aluminum plate and penetration to the steel plate are caused by the RRSCP *** simulation analysis,the RRSCP is formed by a mechanically and chemically coupled response with the reactive liner activated by shock in its outer walls and bottom and then backward overturning,forming a leading reactive penetrator and a following chemical energy *** unique formation structure determines the damage modes of the aluminum plate and the steel *** analysis indicates that the formation behaviors and damage capability of Al-PTFE-Cu RRSCP strongly depend on Cu *** increasing Cu content,the velocity,activation extent,and reaction extent of Al-PTFE-Cu RRSCP decrease,which contribute to elongation and alleviate the negative effects of chemical reactions on elongation,significantly increasing the length-diameter ratio and thus enhancing the capability of steel plate ***,the lower activation extent and energetic density will weaken the RRSCP's capability of causing rupturing damage to the aluminum plate.

关键词： Reactive materials Al-PTFE composites Reactive liner X-ray Penetration

Theoretical analysis of the elastic Kelvin-Helmholtz instability in explosive weldings

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Defence Technology（防务技术） 2024年第2期32卷 521-528页

作者： Yuanbo Sun Jianning Gou cheng Wang Qiang Zhou Rui Liu pengwan chen Tonghui Yang Xiang Zhao State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China Beijing HIWING Scientific and Technological Information Institute Beijing100084China School of Aerospace Engineering Tsinghua UniversityBeijing100084China

By considering the joint effects of the Kelvin-Helmholtz(KH) and Rayleigh-Taylor(RT) instabilities, this paper presents an interpretation of the wavy patterns that occur in explosive welding. It is assumed that the elasticity of the material at the interface effectively determines the wavelength, because explosive welding is basically a solid-state welding process. To this end, an analytical model of elastic hydrodynamic instabilities is proposed, and the most unstable mode is selected in the solid phase. Similar approaches have been widely used to study the interfacial behavior of solid metals in high-energy-density physics. By comparing the experimental and theoretical results, it is concluded that thermal softening,which significantly reduces the shear modulus, is necessary and sufficient for successful welding. The thermal softening is verified by theoretical analysis of the increase in temperature due to the impacting and sliding of the flyer and base plates, and some experimental observations are qualitatively *** summary, the combined effect of the KH and RT instabilities in solids determines the wavy morphology, and our theoretical results are in good qualitative agreement with experimental and numerical observations.

关键词： Explosive welding Hydrodynamic instabilities Elasticity

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石墨烯气凝胶的压缩力学性能研究

兵工学报 2024年第7期45卷 2364-2373页

作者：曹路晴乔扬谢晶陈鹏万北京理工大学爆炸科学与技术重点实验室北京100081 爆炸防护与应急处置技术教育部工程研究中心北京100081

为探究石墨烯气凝胶在防护领域的潜在应用,采用冷冻干燥法并控制冷冻温度变量制备不同的石墨烯气凝胶试样,进行单轴面内压缩力学实验;结合3D数字图像相关技术和扫描电子显微镜,分析变形模式与破坏机理。研究结果表明:冷冻干燥法制备的... 详细信息

为探究石墨烯气凝胶在防护领域的潜在应用,采用冷冻干燥法并控制冷冻温度变量制备不同的石墨烯气凝胶试样,进行单轴面内压缩力学实验;结合3D数字图像相关技术和扫描电子显微镜,分析变形模式与破坏机理。研究结果表明:冷冻干燥法制备的石墨烯气凝胶试样具有3D多孔网络结构、低密度(98.5%)等特征,并具有受冷冻温度影响的特征微观结构;石墨烯气凝胶的压缩应力-应变曲线展现出多孔材料典型的三阶段特征,并且力学性能受冷冻温度的影响,-80℃所得石墨烯气凝胶的杨氏模量相较于-19℃提高160%,单位体积吸能提高67%;石墨烯气凝胶多次循环加载-卸载中随着内部致密区域的扩展,以塑性能为主的吸收总能趋于稳定不变,其状态变化可通过指数衰减模型描述;石墨烯气凝胶的横纵向片层不同的压缩变形形态发展为大规模的类弹簧型紧密折叠模式,使得石墨烯气凝胶表现出回弹性。所得研究成果为石墨烯气凝胶在防护领域的应用提供了理论与实践基础。

关键词：石墨烯气凝胶压缩力学性能冷冻干燥法吸能特性变形模式

维普期刊数据库博看期刊

TiB_(2)/B_(4)C复相陶瓷自蔓延热爆炸烧结与性能表征

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兵工学报 2024年第1期45卷 26-34页

作者：李云飞高鑫陈鹏万刘开源北京理工大学爆炸科学与技术国家重点实验室北京100081 北京理工大学前沿技术研究院山东济南250307

为了探究高硬度复相陶瓷高效且低成本的制备方法,利用自蔓延高温合成结合爆炸烧结技术,开展制备二硼化钛/碳化硼(TiB_(2)/B_(4)C)复相陶瓷的研究,成功制备厚度约为1 cm、直径约为5 cm的TiB_(2)/B_(4)C复相陶瓷块体。烧结样品物相和微观... 详细信息

为了探究高硬度复相陶瓷高效且低成本的制备方法,利用自蔓延高温合成结合爆炸烧结技术,开展制备二硼化钛/碳化硼(TiB_(2)/B_(4)C)复相陶瓷的研究,成功制备厚度约为1 cm、直径约为5 cm的TiB_(2)/B_(4)C复相陶瓷块体。烧结样品物相和微观结构分析表征结果表明:烧结样品中TiB_(2)相和B_(4)C相分布均匀,截面观察到致密的微米级颗粒。该方法制备的样品致密度和硬度较高,随冲击压力不同,致密度范围在90%~93%之间,相应平均维氏硬度为16.64~17.35 GPa;根据不同条件下回收样品的微结构、致密度等分析,冲击压力和起爆时刻生坯温度对TiB_(2)/B_(4)C复相陶瓷烧结质量有重要影响;冲击压力为40 GPa,生坯温度为1800 K时,烧结致密度为93%;为进一步提高烧结质量,应提高冲击压力或冲击波作用时间。研究表明自蔓延热爆炸烧结技术是一种高效且低成本的高硬度复相陶瓷的制备方法。

关键词： TiB_(2)/B_(4)C 复相陶瓷自蔓延高温合成爆炸烧结微观结构

维普期刊数据库博看期刊

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药型罩形状对活性聚能侵彻体成型的影响

北京理工大学学报 2024年第4期44卷 327-335页

作者：孙韬袁盈郑元枫余庆波陈鹏万王海福北京理工大学爆炸科学与技术国家重点实验室北京100081

结合理论与数值模拟,对3种不同形状药型罩活性聚能侵彻体的成型行为开展了研究.数值模拟结果表明,在聚能效应下,球缺罩和大锥角圆锥罩形成尾部带有碎片云的类杆状活性聚能侵彻体,而小锥角圆锥罩则形成活性射流.相比于活性射流,类杆状活... 详细信息

结合理论与数值模拟,对3种不同形状药型罩活性聚能侵彻体的成型行为开展了研究.数值模拟结果表明,在聚能效应下,球缺罩和大锥角圆锥罩形成尾部带有碎片云的类杆状活性聚能侵彻体,而小锥角圆锥罩则形成活性射流.相比于活性射流,类杆状活性聚能侵彻体速度较低,但凝聚性较好.进一步结合活性材料反应动力学方程,对活性聚能侵彻体成型激活反应行为进行分析.分析结果表明:活性射流激活区位于杵体外壁、射流头部和轴线附近;随炸高增加,激活区内活性材料反应不断加剧,特别是射流头部和轴线附近材料的反应,将导致活性射流膨胀发散,不利于侵彻;而类杆状活性聚能侵彻体激活区域主要集中在尾部碎片区和杆尾中心部位,化学反应对其影响相对较小.

关键词：活性材料聚能装药射流药型罩成型行为

Monitoring micro-structural evolution during aluminum sintering and understanding the sintering mechanism of aluminum nanoparticles:A molecular dynamics study

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Journal of Materials Science & Technology 2020年第22期54卷 92-100页

作者： Jun Jiang pengwan chen Weifu Sun State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China Beijing Institute of Technology Chongqing Innovation Center Chongqing401120China

In this work, molecular dynamics simulations have been performed to explore the structural evolution and underlying sintering mechanism of aluminum nanoparticles. The structural evolution during sintering was firstly monitored through radial distribution function and atomic migration, and the underlying sintering mechanism was further quantitatively characterized in terms of average displacement, mean squared distance(MSD), radius ratio(i.e., the ratio of the neck radius to the particle radius), shrinkage and radius of gyration, crystalline orientations, particle size, etc. Results show that the surface atoms of nanoparticles are more active than the internal atoms, favoring the mechanical rotation of nanoparticles during sintering. During the sintering process, average displacement, radius ratio and the shrinkage rate have undergone three stages with increasing the temperature:(1) a slow increase and subsequent abrupt hike after reaching the sintering temperature;(2) an almost plateau region over a wide span of temperature;(3) finally a sharp increase again after reaching the melting temperature. In contrast, MSD remains basically unchanged before melting, close to zero, followed by a sudden increase after melting temperature. Although the radius of gyration also experiences three stages, nonetheless it exhibits almost completely contrary trend. It has also been found that both sintering temperature and melting temperature demonstrate an almost linear increase with the increase of nanoparticle size ranging from4.0, 6.0, 8.0 to 10.0 nm in diameter. Finally, we also found that the particle direction has limited effect on neck growth during sintering.

关键词： Molecular dynamics simulation Aluminum nanoparticle Sintering Mechanical contact Microstructural evolution

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子弹撞击下CL-20基PBX装药响应研究

南京理工大学学报 2024年第2期48卷 127-133页

作者：焦纲领陈鹏万刘睿王志浩张雪丽北京理工大学爆炸科学与技术国家重点实验室北京100081 海军研究院北京100072

为了提高战斗部安全性,指导CL-20基PBX炸药在战斗部装药中的应用和设计,开展了基于子弹撞击试验的典型战斗部撞击响应特性研究。进行了子弹撞击试验,通过分析战斗部响应后的超压数据、验证板穿孔、试验影像和试验样品回收等,评估了子弹... 详细信息

为了提高战斗部安全性,指导CL-20基PBX炸药在战斗部装药中的应用和设计,开展了基于子弹撞击试验的典型战斗部撞击响应特性研究。进行了子弹撞击试验,通过分析战斗部响应后的超压数据、验证板穿孔、试验影像和试验样品回收等,评估了子弹撞击战斗部的反应等级。结果表明,子弹撞击试验中,子弹速度为836 m/s,战斗部在子弹撞击下发生了爆轰等级的反应。此外,开展了不同撞击条件下战斗部安全性数值模拟,研究了不同撞击速度下战斗部的反应过程。结果表明,子弹以850 m/s和750 m/s撞击时,战斗部分别发生爆轰和燃烧等级的反应。该研究为典型战斗部的撞击响应预测及反应等级评价提供了数据支撑。

关键词：战斗部子弹撞击试验评估数值模拟反应等级 CL-20基PBX装药点火增长模型冲击波超压

The atomic interface effect of single atom catalysts for electrochemical hydrogen peroxide production

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Nano Research 2023年第8期16卷 10724-10741页

作者： Kaiyuan Liu pengwan chen Zhiyi Sun Wenxing chen Qiang Zhou Xin Gao State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China Advanced Technology Research Institute Beijing Institute of TechnologyJinan 250307China Energy&Catalysis Center School of Materials Science and EngineeringBeijing Institute of TechnologyBeijing 100081China China Academy of Ordnance Science Beijing 100089China

Producing hydrogen peroxide(H_(2)O_(2))through an electrochemical oxygen reduction reaction(ORR)is a safe,green strategy and a promising alternative to traditional energy-intensive anthraquinone *** and renewable power could be utilized for onsite and decentralized H_(2)O_(2)production,demonstrating significant application ***,single atom catalysts(SACs)have demonstrated significant advantages in the catalytic production of H_(2)O_(2)in 2e−***,the selectivity of SACs in ORR once puzzled *** article reviews the research on the development and achievements of H_(2)O_(2)production by SACs catalysis in recent ***,the structure-performance relationship is a guide to designing new *** advanced characterization techniques and theoretical calculation methods,researchers have a clearer and more thorough understanding of the impact of the atomic interface of SACs on ORR catalytic *** coordination moiety formed between the active metal center atom and the support seriously determines the selectivity of SACs,mainly manifested in the adsorption of*OOH ***,the atomic interface of metal atoms together with O/N co-coordination exhibit high selectivity and mass activity,and heteroatoms or functional groups on carbon supports present synergistic effects to promote the production of H_(2)O_(2)in 2e−*** and accurate regulation of the atomic interface of SACs directly affects the 2e−ORR performance of the ***,it is important to deeply understand the atomic interface of SACs and contribute to the development of novel catalysts.

关键词： single atom catalysts(SACs) atomic interface effect hydrogen peroxide(H_(2)O_(2))production electrochemical catalysis