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Advancing electrochemical drilling process via coupling of flow field and electric field in pulsating state generated by a novel tube tool

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Chinese Journal of Aeronautics 2024年第4期37卷 542-555页

作者： Liang CHENG Xiaolei CHEN Zhisen YE Yongjun ZHANG State key laboratory of Precision Electronic manufacturing technology and Equipment Guangdong University of TechnologyGuangzhou 510006China Guangdong key laboratory of advanced manufacturing technology of Marine Energy Equipment Guangdong University of TechnologyGuangzhou 510006China Guangzhou key laboratory of Nontraditional Machining and Equipment Guangdong University of TechnologyGuangzhou 510006China

This paper introduces an improvement to electrochemical drilling process by coupling flow field and electric field in pulsating state. A novel tube with half-wedged shape at the end(HW-tube) is prepared, with both sidewall and wedged part of the HW-tube insulated. Only the flat part is utilized to provide electric field for electrochemical drilling. By rotating the HW-tube, both flow field and electric field in pulsating state are generated, alternating in different positions within the inter-electrode gap(IEG). The pulsating flow field enhances the mass transfer process, while pulsating electric field disperses material dissolution process and distribution of electrolytic byproducts. Both pulsating fields are coupled at the same frequency, further enhancing the electrochemical drilling process. Simulation results indicate that both flow field and electric field in pulsating state are generated. Compared to the traditional tube, the HW-tube significantly reduces the number of residual particles in IEG, and this number is further reduced by increasing the rotation speed. Experimental results reveal that the surface quality and dimensional uniformity of small hole are improved with HW-tube. With feed rate of 2.22 mm/min, a small hole with diameter of 1.52± 0.017 mm is drilled, resulting in a surface roughness of 0.331 μm.

关键词： Small holes Electrochemical drilling Tools Pulsating flow field Pulsating electric field

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Analysis and Optimization of the Electrohydraulic Forming Process of Sinusoidal Corrugation Tubes

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Fluid Dynamics & Materials Processing 2024年第4期20卷 873-887页

作者： Da Cai Yinlong Song Hao Jiang Guangyao Li Junjia Cui State key laboratory of advanced Design and manufacturing technology for Vehicle Hunan UniversityChangsha410082China

Aluminum alloy thin-walled structures are widely used in the automotive industry due to their advantages related to light weight and crashworthiness.They can be produced at room temperature by the electrohydraulic forming process.In the present study,the influence of the related parameters on the forming quality of a 6063 aluminum alloy sinusoidal corrugation tube has been assessed.In particular,the orthogonal experimental design(OED)and central composite design(CCD)methods have been used.Through the range analysis and variance analysis of the experimental data,the influence degree of wire diameter(WD)and discharge energy(DE)on the forming quality was determined.Multiple regression analysis was performed using the response surface methodology.A prediction model for the attaching-die state coefficient was established accordingly.The following optimal arrangement of parameters was obtained(WD=0.759 mm,DE=2.926 kJ).The attaching-die state coefficient reached the peak value of 0.001.Better optimized wire diameter and discharge energy for a better attaching-die state could be screened by CCD compared with OED.The response surface method in CCD was more suitable for the design and optimization of the considered process parameters.

关键词： Electrohydraulic forming aluminum alloy tube process parameters attaching-die state 1 Introduction

Atomistic study of inverse size effect induced by interfacial plasticity in pearlitic multi-principal element alloy

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Rare Metals 2024年第7期43卷 3341-3355页

作者： Chen Yang Qiao-Sheng Xia Cun-Hong Yin Dong-Peng Hua College of Mechanical Engineering Guizhou University key laboratory of advanced manufacturing technology Ministry of EducationGuizhou University State key laboratory of Solidification Processing Center of Advanced Lubrication and Seal MaterialsNorthwestern Polytechnical University

Owing to the fine nano-laminated structure,the pearlitic multi-principal element alloy（PMPEA） exhibits excellent mechanical and tribological properties.However,the incomplete understanding of the size effect of its lamella thickness and the unclear understanding of the plasticity-interface interaction mechanism limit further optimization of PMPEAs.In this study,the FeCoNi/Ni3Ti interface-mediated plastic deformation behavior in PMPEA and the variation of mechanical and tribological properties with lamella thickness within the nanoscale range using molecular dynamics（MD） simulation were explored.The results indicate that the mechanical and tribological properties of the PMPEA with lamella thicknesses below 10 nm have a significant inverse size effect,i.e.,the smaller the lamella thickness,the weaker the properties.This is because the plastic carrier-interface interaction mechanism changes from a strengthening mechanism that hinders dislocations to a weakening mechanism that promotes dislocations with the decreases in the lamella thickness,and the weakening effect becomes more pronounced as the lamella thickness decreases and the number of interfaces increases.In particular,the deformation behavior of Ni3Ti lamellae changes from crystal-like to amorphous-like with decreasing lamella.Moreover,in the sample with larger lamella thickness,the occurrence of hierarchical slips in the body-centered cubic（BCC） phase due to the multiprincipal elements effect can better alleviate the stress concentration caused by the dislocation accumulation at the interface,so that the phase interface exhibits outstanding load-bearing effects.And the dislocation pattern in BCC phase shows a firm high-density cell,which makes the substrate exhibit a stable tribological response.

关键词： Multi-principal element alloy Nano-laminated structure Molecular dynamics simulation Nanoindentation and nanoscratch

Grain-boundary segregation and grain growth in nanocrystalline substitutional solid solution alloys

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Journal of Materials Science & technology 2024年第1期168卷 239-249页

作者： Fawei Tang Chao Hou Hao Lu Zhi Zhao Xiaoyan Song Faculty of Materials and manufacturing Key Laboratory of Advanced Functional MaterialsMinistry of Education of ChinaBeijing University of TechnologyBeijing 100124China

A model for describing solute segregation at grain boundaries has been developed for substitutional solid solution alloys,which integrates multiple factors from atomic to microstructural scales.A concept of mo-lar Gibbs free energy of segregation was introduced to evaluate the segregating capability of the solute elements in a closed system,through which the influences of grain boundary structure,grain size,ma-terial composition,and external conditions were described.Based on the evaluation of various energy forms related to solute segregation and grain growth processes,the nature of the thermal stabilization of nanograin structures by solute segregation was disclosed.A criterion for the destabilization of nanostruc-tures,which is determined by the competition of the change rates between the molar Gibbs free energy of segregation and the total energy of grain boundaries with grain size,has been proposed.This study provided guideline to achieve high-temperature stability of nanograin structures of solid solution alloys even for the weakly segregating nanocrystalline systems.

关键词： Substitutional solid solution Grain boundary segregation Thermal stabilization Solute concentration Grain size

Artificial Intelligence Meets Flexible Sensors:Emerging Smart Flexible Sensing Systems Driven by Machine Learning and Artificial Synapses

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Nano-Micro Letters 2024年第1期16卷 235-273页

作者： Tianming Sun Bin Feng Jinpeng Huo Yu Xiao Wengan Wang Jin Peng Zehua Li Chengjie Du Wenxian Wang Guisheng Zou Lei Liu Department of Mechanical Engineering State Key Laboratory of Tribology in Advanced EquipmentKey Laboratory for Advanced Manufacturing by Materials Processing TechnologyMinistry of Education of PR ChinaTsinghua UniversityBeijing 100084People’s Republic of China College of Materials Science and Engineering Shanxi ProvinceTaiyuan University of TechnologyTaiyuan 030024People’s Republic of China

The recent wave of the artificial intelligence(AI)revolution has aroused unprecedented interest in the intelligentialize of human society.As an essential component that bridges the physical world and digital signals,flexible sensors are evolving from a single sensing element to a smarter system,which is capable of highly efficient acquisition,analysis,and even perception of vast,multifaceted data.While challenging from a manual perspective,the development of intelligent flexible sensing has been remarkably facilitated owing to the rapid advances of brain-inspired AI innovations from both the algorithm(machine learning)and the framework(artificial synapses)level.This review presents the recent progress of the emerging AI-driven,intelligent flexible sensing systems.The basic concept of machine learning and artificial synapses are introduced.The new enabling features induced by the fusion of AI and flexible sensing are comprehensively reviewed,which significantly advances the applications such as flexible sensory systems,soft/humanoid robotics,and human activity monitoring.As two of the most profound innovations in the twenty-first century,the deep incorporation of flexible sensing and AI technology holds tremendous potential for creating a smarter world for human beings.

关键词： Flexible electronics Wearable electronics Neuromorphic Memristor Deep learning

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High-repetition-rate and high-power efficient picosecond thin-disk regenerative amplifier

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High Power Laser Science and Engineering 2024年第2期12卷 16-23页

作者： Sizhi Xu Yubo Gao Xing Liu Yewang Chen Deqin Ouyang Junqing Zhao Minqiu Liu Xu Wu Chunyu Guo Cangtao Zhou Qitao Lue Shuangchen Ruan key laboratory of advanced Optical Precision manufacturing technology of Guangdong Higher Education Institutes Sino-German College of Intelligent ManufacturingShenzhen Technology UniversityShenzhenChina Han’s Laser technology Industry Group Co. Ltd.ShenzhenChina Shenzhen key laboratory of Laser Engineering College of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhenChina Shenzhen key laboratory of Ultraintense Laser and advanced Material technology College of Engineering PhysicsShenzhen Technology UniversityShenzhenChina

We present an effective approach to realize a highly efficient,high-power and chirped pulse amplification-free ultrafast ytterbium-doped yttrium aluminum garnet thin-disk regenerative amplifier pumped by a zero-phonon line 969 nm laser diode.The amplifier delivers an output power exceeding 154 W at a pulse repetition rate of 1 MHz with custom-designed 48 pump passes.The exceptional thermal management on the thin disk through high-quality bonding,efficient heat dissipation and a fully locked spectrum collectively contributes to achieving a remarkable optical-to-optical efficiency of 61%and a near-diffraction-limit beam quality with an M2 factor of 1.06.To the best of our knowledge,this represents the highest conversion efficiency reported in ultrafast thin-disk regenerative amplifiers.Furthermore,the amplifier operates at room temperature and exhibits exceptional stability,with root mean square stability of less than 0.33%.This study significantly represents advances in the field of laser amplification systems,particularly in terms of efficiency and average power.This advantageous combination of high efficiency and diffraction limitation positions the thin-disk regenerative amplifier as a promising solution for a wide range of scientific and industrial applications.

关键词： high efficiency high power picosecond laser regenerative amplifier thin-disk laser

Phase transition of multi-component(TiZrVNb)C ceramics—Part II:From single phase to multiple phases via adjusting V content

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Journal of advanced Ceramics 2024年第5期13卷 689-698页

作者： Qingyi Kong Lei Chen Sijia Huo Kunxuan Li Wenyu Lu Yujin Wang Yu Zhou Institute for advanced Ceramics School of Materials Science and EngineeringHarbin Institute of TechnologyHarbin 150080China key laboratory of advanced Structure‒Function Integrated Materials and Green manufacturing technology Harbin Institute of TechnologyHarbin 150001China National key laboratory of Precision Hot Processing of Metals Harbin Institute of TechnologyHarbin 150001China

To address the relatively mediocre mechanical properties of single-phase multi-component carbide ceramics,a phase transition from a single phase to multiple phases was proposed to achieve superior mechanical properties.A series of(TiZrVxNb)C0.8 ceramics with different V contents were fabricated by spark plasma sintering(SPS).The influence of the V content on the phase composition,microstructural evolution,and mechanical properties was investigated in detail.The transition behavior from a single phase to multiple phases is discovered and discussed.The formation of the Zr-rich phase and Zr-poor phase can be attributed to the increase in lattice distortion and mixed enthalpy caused by the addition of V.A nanometer lamellar structure with a semi-coherent interface obtained via in situ decomposition is reported for the first time in multi-component carbide ceramics.The semi-coherent interfaces with high dislocation density and strain concentration effectively improve the mechanical properties,grain refinement,and multi-phase formation.The optimal comprehensive mechanical properties of the Vickers hardness(26.3 GPa),flexural strength(369 MPa),and fracture toughness(3.1 MPa·m1/2)were achieved for the sample with 20 mol%V.

关键词： multi-component ceramics multiple phases microstructure evolution phase decomposition mechanical properties

Hot deformation behavior and microstructure evolution of GH3536-TiB2 composites fabricated by powder metallurgy

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Science China Technological Sciences 2024年第7期67卷 2107-2124页

作者： ZHOU ShiPeng WANG Shuai HUANG LuJun ZHANG Rui CHEN Xin MENG FanChao CHEN Run SUN FengBo WANG CunYu GENG Lin School of Materials Science and Engineering Harbin Institute of Technology State key laboratory of advanced Welding and Joining Harbin Institute of Technology Waikato Centre for advanced Materials and manufacturing School of Engineering University of Waikato

The hot deformation behavior and microstructure evolution of GH3536-TiB2composites fabricated by powder metallurgy（PM）were examined in the temperature range of 950–1150°C and strain rate range of 0.001–1 s-1. The hot compression stress-strain curves and the constitutive equation were obtained. In addition, the hot processing map was drawn, which indicated that the appropriate hot working window was 950–1050°C/0.001–0.1 s-1and 1050–1100°C/0.001–0.01 s-1. The microstructure analysis showed that the splitting and spheroidization of M3B2led to a decrease in size and volume fraction at 950–1100°C. At 1150°C,the eutectic microstructure of M3B2+ γ was formed due to the dissolution of M3B2, which caused macroscopic cracking of the deformed sample. Additionally, the deformation temperature and the strain rate had little effect on the size and volume fraction of M3B2. Besides, discontinuous dynamic recrystallization（DDRX） and continuous dynamic recrystallization（CDRX） were found in the deformed microstructure, while the former was dominant. Within the test range of this work, the dynamic recrystallization（DRX） fraction of the deformed composites was high due to the bulging nucleation of numerous interfaces. The DRX grain size increased with increasing deformation temperature or decreasing strain rate. Texture analysis showed that the deformation texture of //compression direction RD existed in the matrix when the deformation temperature was below 1100°C, and the texture type became //RD at 1100°C. Additionally, it was also found that the //RD texture was formed in M3B2under the strain rates of 0.1 and 0.01 s-1.

关键词： GH3536 alloy matrix composites powder metallurgy hot deformation behavior microstructure evolution

Advances in sodium-ion batteries at low-temperature: Challenges and strategies

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Journal of Energy Chemistry 2024年第3期90卷 518-539,I0012页

作者： Haoran Bai Xiaohui Zhu Huaisheng Ao Guangyu He Hai Xiao Yinjuan Chen key laboratory of advanced Catalytic Materials and technology Advanced Catalysis and Green Manufacturing Collaborative Innovation CenterChangzhou UniversityChangzhou 213164JiangsuChina Department of Chemistry Tsinghua UniversityBeijing 100084China

With the continuing boost in the demand for energy storage,there is an increasing requirement for batteries to be capable of operation in extreme environmental conditions.Sodium-ion batteries(SIBs) have emerged as a highly promising energy storage solution due to their promising performance over a wide range of temperatures and the abundance of sodium resources in the earth's crust.Compared to lithiumion batteries(LIBs),although sodium ions possess a larger ionic radius,they are more easily desolvated than lithium ions.Fu rthermore,SIBs have a smaller Stokes radius than lithium ions,resulting in improved sodium-ion mobility in the electrolyte.Nevertheless,SIBs demonstrate a significant decrease in performance at low temperatures(LT),which constrains their operation in harsh weather conditions.Despite the increasing interest in SIBs,there is a notable scarcity of research focusing specifically on their mechanism under LT conditions.This review explores recent research that considers the thermal tolerance of SIBs from an inner chemistry process perspective,spanning a wide temperature spectrum(-70 to100℃),particularly at LT conditions.In addition,the enhancement of electrochemical performance in LT SIBs is based on improvements in reaction kinetics and cycling stability achieved through the utilization of effective electrode materials and electrolyte components.Furthermore,the safety concerns associated with SIBs are addressed and effective strategies are proposed for mitigating these issues.Finally,prospects conducted to extend the environmental frontiers of commercial SIBs are discussed mainly from three viewpoints including innovations in materials,development and research of relevant theoretical mechanisms,and intelligent safety management system establishment for larger-scale energy storage SIBs.

关键词： Low-temperature Sodium-ion batteries Reaction kinetics Cycle stability Safety concerns of Sodium-ion batteries

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