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Defence Technology（防务技术） 2024年第5期35卷 1-17页

作者： Hao Xue Tao Wang Xinyu Cui Yifan Wang Guangyan Huang state Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

Material and structure made by additive manufacturing(AM)have received much attention lately due to their flexibility and ability to customize complex *** study first implements multiple objective topology optimization simulations based on a projectile perforation model,and a new topologic projectile is *** two types of 316L stainless steel projectiles(the solid and the topology)are printed in a selective laser melt(SLM)machine to evaluate the penetration performance of the projectiles by the ballistic *** experiment results show that the dimensionless specific kinetic energy value of topologic projectiles is higher than that of solid projectiles,indicating the better penetration ability of the topologic ***,microscopic studies(scanning electron microscope and X-ray micro-CT)are performed on the remaining projectiles to investigate the failure mechanism of the internal structure of the topologic *** explicit dynamics simulation was also performed,and the failure locations of the residual topologic projectiles were in good agreement with the experimental results,which can better guide the design of new projectiles combining AM and topology optimization in the future.

关键词： Additive manufacturing Topology optimization Ballistic performance Projectile design

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

Energy release characteristics of PTFE/Al/TiH_(2) reactive jet with different TiH_2 content

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Defence Technology（防务技术） 2024年第9期39卷 168-176页

作者： Chunlan Jiang Jingbo Zhang Rong Hu Liang Mao Ming Li state Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

Titanium hydride(TiH_(2)), a promising high-energy additive, is doped into PTFE/Al to optimize the energy output structure of the reactive jet and strive for better aftereffect damage ability to the target. Six types of PTFE/Al/TiH_(2) reactive liners with different TiH_(2) content are prepared by the molding and sintering method. The energy release characteristics of PTFE/Al/TiH_(2) reactive jet are tested by the transient explosion energy test, and are characterized from pressure and temperature. The reaction delay time,pressure history, and temperature history of the energy release process are obtained, then the actual value of released energy and reaction efficiency of the reactive jet are calculated. The results show that the peak pressure and temperature of the PTFE/Al/TiH_(2) jet initially increase and then decrease with increasing TiH_(2) content. When the TiH_(2) content is 10%, the actual value of released energy and reaction efficiency increased by 24% and 6.4%, respectively, compared to the PTFE/Al jet. The reaction duration of the reactive material is significantly prolonged as the TiH_(2) content increased from 0% to 30%. Finally,combined with the energy release behaviors of PAT material and the dynamic deformation process of liner, the enhancement mechanism of TiH_(2) on energy release of the reactive jet is expounded.

关键词： PTFE/Al/TiH_(2) Reactive materials Shaped charge Impact energy release characteristics

Propagation Properties of Shock Waves in Polyurethane Foam based on Atomistic Simulations

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Defence Technology（防务技术） 2024年第1期31卷 117-129页

作者： Zhiqiang Hu Jianli Shao Shiyu Jia Weidong Song Cheng Wang state Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

Porous materials are widely used in the field of protection because of their excellent energy absorption *** this work,a series of polyurethane microscopic models are established and the effect of porosity on the shock waves is studied with classical molecular dynamics ***,shock Hugoniot relations for different porosities are obtained,which compare well with the experimental *** pores collapse and form local stress wave,which results in the complex multi-wave structure of the shock *** microstructure analysis shows that the local stress increases and the local velocity decreases gradually during the process of pore collapse to complete ***,it leads to stress relaxation and velocity *** shock stress peaks can be fitted with two exponential functions,and the amplitude of attenuation coefficient decreases with the increase of ***,the pore collapse under shock or non-shock are discussed by the entropy increase rate of the *** energy is dissipated mainly through the multiple interactions of the waves under *** energy is dissipated mainly by the friction between atoms under non-shock.

关键词： Polyurethane foam Shock wave Attenuation Atomistic simulation

Research on mass loss and nose shape evolution of kinetic energy projectiles penetrating concrete at high velocity

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Acta Mechanica Sinica 2024年第7期40卷 92-108页

作者： Zhiyan Yao Fenglei Huang Jinzhu Li state Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

The high-speed penetration of concrete targets by kinetic energy projectiles results in apparent mass loss,which blunts the nose of the projectile and decrease its penetration *** friction work between the projectile and the concrete target,the plastic deformation of the projectile,and the cutting of aggregates to the projectile significantly affect the mass loss of the *** address these effects,a discrete iterative model is developed for the mass loss and nose shape evolution of the projectile by coupling three mechanisms based on the effect of temperature on *** the model,both friction work and plastic work increase the temperature of the projectile's surface layer,thereby weakening the strength of this part and rendering it easier for mass loss to occur due to aggregate *** model discretizes the projectile and penetration process with respect to the space and time dimensions,*** mass loss and nose shape evolution of the projectile are obtained by iteratively calculating a point-by-point *** predicted depth of penetration(DOP),mass loss,and residual projectile profile are compared with experimental data to validate the *** comparison shows satisfactory agreement between the calculated results and experimental ***,the deceleration,velocity,DOP,and mass loss during penetration are analyzed with respect to ***,based on the model,the effects of projectile strength,caliber-radius-head(CRH),and concrete target strength on penetration are discussed.

关键词： Kinetic energy projectile High-velocity penetration Coupled model Mass loss Nose shape evolution

Assessing the energy release characteristics during the middle detonation reaction stage of aluminized explosives

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Defence Technology（防务技术） 2024年第3期33卷 270-277页

作者： Kun Yang Lang Chen Danyang Liu Bin Zhang Jianying Lu Junying Wu state Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

Afterburning behind the detonation front of an aluminized explosive releases energy on the millisecond timescale,which prolong the release of detonation energy and the energy release at different stages also shows significant ***,at present,there are few effective methods for evaluating the energy release characteristics of the middle reaction stage of such explosives,which can have a duration of tens to hundreds of *** present work demonstrates an approach to assessing the midstage of an aluminized explosive detonation based on a water push test employing a high degree of *** this method,the explosive is contained in a steel cylinder having one end closed that is installed at the bottom of a transparent water *** detonation,the gaseous products expand in one direction while forcing water ahead of *** resulting underwater shock wave and the interface between the gas phase products and the water are tracked using an ultra-high-speed framing and streak *** shock wave velocity in water and the expansion work performed by the gaseous detonation products were calculated to assess the energy release characteristics of aluminized explosives such as CL-20 and RDX in the middle stage of the detonation *** the middle stage of the detonation process of these aluminized explosives,the aluminum reaction reduced the attenuation of shock waves and increased the work performed by gas phase products.A higher aluminum content increased the energy output while the presence of oxidants slowed the energy release *** work demonstrates an effective means of evaluating the performance of aluminized explosives.

关键词： Aluminized explosive Non-ideal detonation Water push test Energy release

A versatile humanoid robot platform for dexterous manipulation and human-robot collaboration

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CAAI Transactions on Intelligence Technology 2024年第2期9卷 526-540页

作者： Xin Shu Fenglei Ni Xinyang Fan Shuai Yang Changyuan Liu Baoxu Tu Yiwei Liu Hong Liu state Key Laboratory of Robotics and System Harbin Institute of TechnologyHarbinChina

Humanoid robots have attracted much attention by virtue of their compatibility with human ***,biped humanoids with immense promise still cannot function steadily and reliably in real-world settings in the current ***,rationally combining a humanoid robot with different stable mobile platforms is a favoured solution for diverse ***,a new versatile humanoid robot platform,aiming to provide a generic solution that can be flexibly deployed in diverse scenarios,for example,indoors and fields is *** humanoid robot platform incorporates multimodal perception,and extensible interfaces on hardware and software,allowing it to be rapidly integrated with different mobile platforms and end-effectors,only through easyto-assemble ***,the platform has achieved impressive integration,lightness,dexterity,and strength in its class,with human-like size and rich perception,targeted to have human-intelligent manipulation skills for human-engineered ***,this article elaborates on the reasoning behind the design choices,and outlines each ***,the essential performance of the platform is successfully demonstrated in a set of experiments with precise and dexterous manipulation,and human–robot collaboration requirements.

关键词： intelligent robots robotics

Electrodeposition of rare refractory metals in low-temperature ionic liquids

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Rare Metals 2024年第10期43卷 4921-4933页

作者： Lin-Lin Wang Han-Dong Jiao Rui Yuan Le-Yang Li Man-Peng Lin Rui-Yang Sun Jiu-San Xiao Shu-Qiang Jiao institute of Advanced Structure Technology Beijing Institute of Technology state Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing

Rare refractory metals(RRMs) play a significant role in fundamental industries, including electronics,chemical industry, machinery, etc., and future advanced fields, such as aerospace and superconductivity. However,the traditional production processes of RRMs based on high-temperature thermal reduction cannot meet the requirements of low-energy consumption. This dilemma could be addressed efficiently by using a low-temperature electrodeposition strategy in ionic liquids(ILs). This review summarizes a panoramic view of the latest developments on the electrodeposition of RRMs in ILs after a brief review on the current industrial production methods of RRMs. Based on this, the electrochemical mechanism occurring at the cathode during the electrodeposition process of RRMs in different electrolytes and under different conditions is thoroughly discussed, because it is crucial for the successful production of pure RRMs. In addition, this review not only analyses the main challenges that hinder the industrial application of the electrodeposition of RRMs in ILs, but also proposes corresponding solutions. We hope this review can provide a valuable guidance for the fundamental research and industrial development of lowtemperature electrodeposition of RRMs.

关键词： Chemical industry

Unraveling the mysteries of volatile cycling and habitability on Earth and beyond

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National Science Review 2024年第6期11卷 8-9页

作者： Yi-Gang Xu Ri-Xiang Zhu Min-Han Dai state Key Laboratory of Isotope Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences state Key Laboratory of Lithosphere Evolution Institute of Geology and Geophysics Chinese Academy of Sciences state Key Laboratory of Marine Environmental Science Xiamen University

The origin and cycling of volatiles, including water, carbon dioxide, and nitrogen, are fundamental to the very existence of habitable planets. These volatile compounds, often taken for granted,are the lifeblood of planetary systems, influencing almost everything from atmospheric composition and climate regulation to deep Earth processes and the emergence of life.

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Microstructure features induced by fatigue crack initiation up to very-high-cycle regime for an additively manufactured aluminium alloy

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Journal of Materials Science & Technology 2024年第6期173卷 247-260页

作者： Xiangnan Pan Leiming Du Guian Qian Youshi Hong state Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of SciencesBeijing 100190China

Fatigue failure can still occur beyond 107 cycles,***-high-cycle fatigue(VHCF),in many metallic materials,such as aluminium alloys and high-strength *** VHCF of high-strength steels,a fine granular area(FGA)surrounding an inclusion is commonly identified as the characteristic region of crack initiation on the fracture ***,no such FGA feature and related crack initiation behaviour were observed in VHCF of conventionally cast or wrought aluminium ***,we first reported the distinct mechanisms of crack initiation and early growth,namely the microstructure feature and the role of FGA in VHCF performance for an additively manufactured(AM)AlSi10Mg *** AM pores play a key role in fatigue crack initiation similar to that of the inclusions in high-strength steels,resulting in almost identical FGA behaviour for different materials under a range of mean stress with a stress ratio at R*** profile microstructure of FGA is identified as a nanograin layer with Si rearrangement and grain boundary *** process consumes a large amount of cyclic plastic energy making FGA undertake a vast majority of VHCF *** results will deepen the understanding of VHCF nature and shed light on crack initiation mechanism of other aluminium and AM alloys.

关键词： Aluminium alloy Additive manufacturing Nanograins Very-high-cycle fatigue(VHCF) Crack initiation Mean stress