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Solid-State Hydrogen Storage Properties of Ti-V-Nb-Cr High-Entropy Alloys and the Associated Effects of Transitional Metals(M=Mn,Fe,Ni)

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Acta Metallurgica Sinica(English Letters) 2023年第7期36卷 1113-1122页

作者： Bo Cheng Yunkai Li Xiaoxi Li Huibin Ke Liang Wang Tangqing Cao Di Wan Benpeng Wang Yunfei Xue Yangtze Delta Region Academy of Beijing Institute of Technology Jiaxing314019China School of Materials Science and Engineering Beijing Institute of TechnologyBeijing100081China Institute of Advanced Structure Technology Beijing Institute of TechnologyBeijing100081China Department of Mechanical and Industrial Engineering Norwegian University of Science and Technology7491TrondheimNorway

Recently,high-entropy alloys(HEAs)designed by the concepts of unique entropy-stabilized mechanisms,started to attract widespread interests for their hydrogen storage *** with body-centered cubic(BCC)structures present a high potential for hydrogen storage due to the high hydrogen-to-metal ratio(up to H/M=2)and vastness of *** many studies reported rapid absorption kinetics,the investigation of hydrogen desorption is missing,especially in BCC *** have investigated the crystal structure,microstructure and hydrogen storage performance of a series of HEAs in the Ti-V-Nb-Cr *** types of TiVCrNb HEAs(Ti_(4)V_(3)NbCr_(2),Ti_(3)V_(3)Nb2Cr_(2),Ti_(2)V_(3)Nb_(3)Cr_(2))with close atomic radii and different valence electron concentrations(VECs)were designed with single BCC phase by CALPHAD *** three alloys with fast hydrogen absorption kinetics reach the H/M ratio up to ***,Ti_(4)V_(3)NbCr_(2)alloy shows the hydrogen storage capacity of 3.7 wt%,higher than other HEAs ever *** dehydrogenation activation energy of HEAs’hydride has been proved to decrease with decreasing VEC,which may be due to the weakening of alloy atom and H ***,Ti_(4)V_(3)NbCr_(2)M(M=Mn,Fe,Ni)alloys were also synthesized to destabilize *** addition of Mn,Fe and Ni lead to precipitation of Laves phase,however,the kinetics did not improve further because of their own excellent hydrogen *** increasing the content of Laves phase,there appear more pathways for hydrogen desorption so that the hydrides are more easily dissociated,which may provide new insights into how to achieve hydrogen desorption in BCC HEAs at room temperature.

关键词： High-entropy alloy Hydrogen storage CALPHAD Hydride stability Hydrogen sorption kinetics

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A numerical method for predicting bursting strength of composite rocket motor case considering filament winding process-induced stress

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Chinese Journal of Aeronautics 2025年第2期38卷 505-518页

作者： Jiqiu LIANG Fei ZHAO Dan WU Anxin DING Hubei Key Laboratory of Advanced Aerospace Propulsion Technology Wuhan 430040China System Design Institute of Hubei Aerospace Technology Academy Wuhan 430040China School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China

A numerical method to predict the bursting strength of filament wound composite rocket motor case is proposed *** method can evaluate the longitudinal stress evolution of each composite layer as impregnated filaments with fiber tension are wound layer by layer,and consider the effects of accumulated stress and deformation during filament winding on the bursting strength of composite ***∅520 mm composite cases as a case study,the filament-winding-process-induced stress and deformation as well as progressive damage behavior are numerically predicted,followed by a comparison with experimental *** numerical results show that the predicted bursting pressures for composite cases manufactured on the mandrels with and without a flexible component are 14.20 MPa and 21.40 MPa,*** values exhibit slight deviation from the measured pressures of 13.50 MPa and 21.57 ***,the predicted damage locations,situated respectively in the dome and cylinder,agree well with the experimental *** observations indicate that use of flexible component reduces the load-bearing capacity of the ***,it validates the reliability and accuracy of the proposed numerical method in predicting the bursting strength of composite cases.

关键词： Composite case Fiber tension Bursting strengt hProgressive damage analysis Filament winding

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A Three-Dimensional SPH Simulation of Lander Footpad Impact on a Lunar Regolith Bed

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Computer Modeling in engineering & Sciences 2025年第2期142卷 2045-2066页

作者： Wanqing Yuan Huiying Xie Can Huang Xiaoliang Wang Qingquan Liu Department of Mechanics School of Aerospace EngineeringBeijing Institute of TechnologyBeijing100081China Institute of Computational Aerodynamics China Aerodynamics Research and Development CenterMianyang621000China Institute of Large Structures for Advanced Industrial Equipment Beijing Institute of TechnologyZhuhai519088China

Landing spacecraft experience significant impact forces during landing,resulting in large deformation and failure in the soil surface,which severely affects landing safety and *** paper establishes a smoothed particle hydrodynamics(SPH)model based on the theory of soil elastoplastic constitutive relations to describe the process of a lander’s footpad impacting lunar regolith *** model can provide engineering indices such as impact load and penetration depth,and illustrate the large deformation and crater characteristics of the regolith.A detailed analysis of the response of the footpad and lunar regolith during landing reveals that the process can be broadly divided into two stages of rapid penetration and oscillatory ***,there are significant similarities in the landing process under different landing velocities and footpad *** research investigates the large deformation and crater characteristics of the lunar regolith *** results demonstrate two failure modes in the *** the impact of a footpad with a smaller mass,the final failure surface of the regolith exhibits a bowl-shaped profile with a uniformly open *** contrast,under the impact of a footpad with a larger mass,the final failure surface of the regolith presents an urn-shaped profile with a large abdomen and a small ***,the impact craters in both scenarios show a bowl-like *** cases of high-velocity impacts,the impact crater exhibits obvious blocky spalling on its *** SPH model developed in this study can be applied to predict the large deformation and failure response of lunar soil under the impact of rigid structures as well as the impact load and penetration *** effectively predicts the dynamic response of the landing process,which is expected to provide a reference for engineering design.

关键词： SPH footpad load lunar regolith impact crater

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Constellation-Preserving Symbol Encryption with Minimal Impact on Fiber Non-linear Channels 8

Constellation-Preserving Symbol Encryption with Minimal Impa...

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8th Optoelectronics Global Conference, OGC 2023

作者： Shimada, Keiji Matsumoto, Ryosuke Kodama, Takahiro Kagawa University Faculty of Engineering and Design Takamatsu Japan National Institute of Advanced Industrial Science and Technology Tsukuba Japan

We showed that uniform-QAM constellation-preserving symbol encryption is below the FEC limit Q2 in any fiber transmission distance without decryption. 32Gbaud 7ch-WDM-DP-16QAM transmission experiments under the condit... 详细信息

ISBN: (纸本)9798350325324

关键词： Quadrature amplitude modulation

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Slip system analysis of magnesium alloy AZ31B in warm compression by Visco-Plastic Self-Consistent simulation

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Keikinzoku/Journal of Japan institute of Light Metals 2024年第2期74卷 73-82页

作者： Matsuoka, Yusuke Bian, Mingzhe Tsukada, Yuhki Koyama, Toshiyuki Chino, Yasumasa Department of Materials Design Innovation Engineering Graduate School of Engineering Nagoya University Furo-Cho Chikusa-Ku Aichi Nagoya-shi464-8603 Japan Department of Materials Design Innovation Engineering Graduate School of Engineering Nagoya University Aichi Nagoya-shi Japan Multi-Material Research Institute National Institute of Advanced Industrial Science and Technology（AIST） Aichi Nagoya-shi Japan

The active deformation mode (slip systems and twinning) of extruded AZ31B alloy (Mg-3Al-1Zn, mass%) during compression at RT, 100°C and 150°C was investigated by visco-plastic self-consistent (VPSC) simulation. Compression tests were first performed to obtain compression curve of AZ31B. The VPSC model was fitted to the compression curves to estimate the Voce hardening parameters which are required for the VPSC simulation. In the case of compression along the extrusion direction, work-hardening occurred rapidly with the transition of dominant deformation modes at all temperatures. In the case of compression to the other directions, basalslip was dominant throughout the deformation at all compression temperatures. In addition, prismaticslip and tensile twin were active in the early stage of deformation, and pyramidalslip became active in the later stage of deformation. Pyramidalslip became more active with increasing temperature from RT to 100°C, whereas basaland prismaticslips became more active with increasing temperature from 100°C to 150°C. These different trends in the change of the active slip system with increasing temperature can be attributed to the CRSS maximum of the pyramidalslip located around 100°C. © 2024 Japan institute of Light Metals. All rights reserved.

关键词： Magnesium alloys

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Comprehensive Biomechanical Characterization of the Flexible Cat Spine via Finite Element Analysis,Experimental Observations,and Morphological Insights

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Journal of Bionic engineering 2024年第6期21卷 2877-2892页

作者： Da Lu Xueqing Wu Yangyang Xu Shijia Zhang Le Zhang Xin Huang Baoqing Pei Beijing Key Laboratory for Design and Evaluation Technology of Advanced Implantable&Interventional Medical Devices Beijing Advanced Innovation Center for Biomedical EngineeringSchool of Biological Science and Medical EngineeringBeihang UniversityBeijing100083China Shenzhen Institute of Beihang University Shenzhen518000China

Felids,during intense activities such as jumping and sprinting,adjust their posture by twisting and stretching their body to disperse limb impact and minimize *** self-stabilization mechanism has garnered significant attention for inspiring biometric robot *** study investigates the flexibility and cushioning characteristics of a cat’s spine,focusing on its biomechanical properties.A high-fidelity 3D model was used to test the range of motion(ROM)under six conditions,simulate dorsiflexion to analyze stress *** torsional and compressive stiffness were tested by using five cat spinal *** flexibility principles of the flexible cat’s spine were explained via morphological *** indicate that the cat spine has the least rotational stiffness in axial rotation,followed by extension and lateral bending,with a compressive stiffness of 53.62±4.68 N/*** during dorsiflexion is evenly distributed across *** vertebrae heights account for 90.34%of total spinal length with a mean height-to-width ratio of ***’spines,with more articulations and elongated vertebrae,allow for significant twisting and bending,aiding in rapid body posture adjustments and impact *** biomechanical traits could inspire the design of robots for confined rescue operations.

关键词： Cat spine Biomechanical characterization Finite element analysis Morphological measurement Flexibility testing

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Learning-based tracking control of AUV:Mixed policy improvement and game-based disturbance rejection

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CAAI Transactions on Intelligence technology 2025年第2期10卷 510-528页

作者： Jun Ye Hongbo Gao Manjiang Hu Yougang Bian Qingjia Cui Xiaohui Qin Rongjun Ding State Key Laboratory of Advanced Design and Manufacturing Technology for Vehicle College of Mechanical and Vehicle EngineeringHunan UniversityChangshaChina School of Information Science and Technology and Institute of Advanced TechnologyUniversity of Science and Technology of ChinaHefeiChina Nanyang Technological University SingaporeSingapore Wuxi Intelligent Control Research Institute of Hunan University Hunan UniversityWuxiChina

A mixed adaptive dynamic programming(ADP)scheme based on zero-sum game theory is developed to address optimal control problems of autonomous underwater vehicle(AUV)systems subject to disturbances and safe *** combining prior dynamic knowledge and actual sampled data,the proposed approach effectively mitigates the defect caused by the inaccurate dynamic model and significantly improves the training speed of the ADP ***,the dataset is enriched with sufficient reference data collected based on a nominal model without considering modelling ***,the control object interacts with the real environment and continuously gathers adequate sampled data in the *** comprehensively leverage the advantages of model-based and model-free methods during training,an adaptive tuning factor is introduced based on the dataset that possesses model-referenced information and conforms to the distribution of the real-world environment,which balances the influence of model-based control law and data-driven policy gradient on the direction of policy *** a result,the proposed approach accelerates the learning speed compared to data-driven methods,concurrently also enhancing the tracking performance in comparison to model-based control ***,the optimal control problem under disturbances is formulated as a zero-sum game,and the actor-critic-disturbance framework is introduced to approximate the optimal control input,cost function,and disturbance policy,***,the convergence property of the proposed algorithm based on the value iteration method is ***,an example of AUV path following based on the improved line-of-sight guidance is presented to demonstrate the effectiveness of the proposed method.

关键词： adaptive dynamic programming autonomous underwater vehicle game theory optimal control reinforcement learning

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Issues Involved in Thermal Camera Calibration Via a Checkerboard Made with LED Bulbs 1

Issues Involved in Thermal Camera Calibration Via a Checkerb...

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1st IEEE International Conference on Smart Power Control and Renewable Energy, ICSPCRE 2024

作者： Garanayak, H. Pandey, Sharat Patra, Dipti National Institute of Technology Department of Electrical Engineering Rourkela India National Institute of Technology Department of Industrial Design Rourkela India

ISBN: (纸本)9798350377002

Thermal camera calibration is indispensable as it is used to measure the temperature in the spatial plane. In the present study, a calibrator checkerboard is devised where the heating elements are LED bulbs. The experimental study discovers that when the checkerboard is kept in a vertical position, the natural convection takes place and the captured thermal images are not suitable for calibration whereas the horizontal position is found to be suitable for calibration. The said calibrator is designed with the Lego concept, which enables the user to arrange the thermal block, the LED bulb in the present study, in the spatial plane. The low resolution of the thermal image is further processed via an image processing scheme which is comprised of image resizing via a super-resolution technique, denoising filtering, thresholding, and morphological operations. The filtered images are further used for calibration of the camera and the observed error is around ±2%. © 2024 IEEE.

关键词： Temperature indicating cameras

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Hierarchical Voronoi Structure Inspired by Cat Paw Pads Substantially Enhances Landing Impact Energy Dissipation

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Journal of Bionic engineering 2024年第4期21卷 1847-1861页

作者： Da Lu Baoqing Pei Yangyang Xu Mengyuan Hu Shijia Zhang Le Zhang Xin Huang Yangwei Wang Xueqing Wu Beijing Key Laboratory for Design and Evaluation Technology of Advanced Implantable&Interventional Medical Devices Beijing Advanced Innovation Center for Biomedical EngineeringSchool of Biological Science and Medical EngineeringBeihang University100083BeijingChina National Key Laboratory of Science and Technology on Materials under Shock and Impact Beijing Institute of Technology100081BeijingChina Shenzhen Institute of Beihang University 518000ShenzhenChina

When a human lands from a high drop,there is a high risk of serious injury to the lower *** the other hand,cats can withstand jumps and falls from heights without being fatally wounded,largely due to their impact-resistant paw *** aim of the present study was to investigate the biomechanism of impact resistance in cat paw pads,propose an optimal hierarchical Voronoi structure inspired by the paw pads,and apply the structure to bionic cushioning shoes to reduce the impact force of landing for *** microstructure of cat paw pads was observed via tissue section staining,and a simulation model was reconstructed based on CT to verify and optimize the structural cushioning *** distribution pattern,wall thickness of compartments,thickness ratio of epidermis and dermis,and number of compartments in the model were changed and simulated to achieve an optimal composed structure.A bionic sole was 3D-printed,and its performance was evaluated via compression test and a jumping-landing *** results show that cat paw pads are a spherical cap structure,divided from the outside to the inside into the epidermis,dermis,and compartments,each with different cushioning capacities.A finite element simulation of different cushioning structures was conducted in a cylinder with a diameter of 20 mm and a height of 10 mm,featuring a three-layer *** optimal configuration of the three layers should have a uniform distribution with 0.3–0.5 mm wall thickness,a 1:1–2 thickness ratio of epidermis and dermis,and 100–150 compartments.A bionic sole with an optimized structure can reduce the peak impact force and delay the peak arrival *** energy absorption rate is about 4 times that of standard *** jumping 80,100,and 120 cm,the normalized ground reaction force is also reduced by 8.7%,12.6%and 15.1%compared with standard *** study provides theoretical and technical support for effective protection against human lower limb landing injuries.

关键词： Cat paw pads Hierarchical Voronoi structure Landing impact Energy dissipation Bionic sole

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Outstanding strength and conductivity of metallic glass composites with multiscale configuration

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Rare Metals 2023年第9期42卷 3099-3113页

作者： Wei-Zong Bao Jie Chen Jun-Zhi Li Bo-Hua Yu Chu-Yuan Liu Ping Jiang Zu-Jia Liu Kai-Tao Hu Dmitri V.Louzguine-Luzgin Guo-Qiang Xie School of Materials Science and Engineering Harbin Institute of Technology(Shenzhen)Shenzhen518055China Advanced Institute for Materials Research(WPI-AIMR) Tohoku UniversitySendai980-8577Japan MathAM-OIL National Institute of Advanced Industrial Science and Technology(AIST)Sendai980-8577Japan State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin150001China

Cu-based composites with multiscale configuration for electrical contact applications are fabricated via a ball milling(BM)-spark plasma sintering(SPS)-aging *** strengthening of the Cu alloy matrix by micro-scale metallic glass particles and nanoscale intracrystalline precipitation phases is *** annealing technique achieves the decomposition of solute atoms in the Cu alloy,ensuring the excellent electrical properties of the matrix conductive *** composite with multiscale configuration achieves an outstanding combination of ultimate compressive strength of(1114±15)MPa and electrical conductivity of 33.0%±1.1%International Annealed Copper Standard(IACS)after annealing at 400.C for 10.0 *** of the strengthening and conductivity mechanisms suggests that the precipitation of the Cr-rich phase within the matrix crystals is a critical contributor to the concerted enhancement of strength and *** addition,the positive role of nanocrystals precipitated at the edges of metallic glass particles on the interfacial bonding of composites is addressed.

关键词： Metallic glass composites Multiscale configuration Strength Conductivity

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