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Three-dimensional Cure Simulation of Stiffened Thermosetting composite Panels

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Journal of materials Science & technology 2010年第5期26卷 467-471页

作者： Guangquan Yue,boming zhang ,Fuhong Dai and Shanyi Du {2. for composite materials,harbin institute of technology,harbin 150080,china [a] center for composite {2. harbin institute of {2. harbin 150080 china

Stiffened thermosetting composite panels were fabricated with co-curing *** the co-curing processing,the temperature distribution in the composite panels was *** investigation into the threedimensional cure simulation of T-shape stiffened thermosetting composite panels was *** tools and locating tools were considered in the cure *** distribution in the composites was predicted as a function of the autoclave temperature history.A nonlinear transient heat transfer finite element model was developed to simulate the curing process of stiffened thermosetting composite *** a simulation example was presented to demonstrate the use of the present finite element procedure for analyzing composite curing *** glass/polyester structure was investigated to provide insight into the nonuniform cure process and the effect of flexible tools and locating tools on temperature *** gradient in the intersection between the skin and the flange was shown to be strongly dependent on the structure of the flexible tools and the thickness of the skin.

关键词： Thermosetting composite Stiffened panels Co-curing Numerical simulation

Valence electron structure and properties of stabilized ZrO_2

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Science china(Technological Sciences) 2008年第7期51卷 1008-1016页

作者： LI JinPing, HAN JieCai, MENG SongHe & zhang XingHong center for {2. materials, harbin institute of technology, harbin 150001, china 1. center for composite {2. Harbin Institute of Technology Harbin 150001 China

To reveal the properties of stabilizers in ZrO2.on nanoscopic levels, the valence electron structures of four stable ZrO2.phases and c-ZrO2.were analyzed on the basis of the empirical electron theory of solids and molecules. The results showed that the hybridization levels of Zr atoms in c-ZrO2.doped with Ca and Mg dropped from B17 to B13, the hybridization levels of Zr atoms in c-ZrO2.doped with Y and Ce dropped from B17 to B15, and that the four stabilizing atoms all made the hybridization levels of O atoms drop from level 4 to level 2. The numbers of covalent electrons in the strongest covalent bond in the descending order are c-ZrO2.Zr0.82.e0.18O2. Zr0.82.0.18O1.91>Zr0.82.g0.18O1.82.Zr0.82.a0.18O1.82. The bond energies of the strongest covalent bond and the melting points of the solid solutions in the descending order are Zr0.82.e0.18O2. c-ZrO2.Zr0.82.0.18O1.91>Zr0.82.g0.18O1.82.Zr0.82.a0.18O1.82. The percent-ages of the total number of covalent electrons in the descending order are c-ZrO2.Zr0.82.0.18O1.91> Zr0.82.e0.18O2.Zr0.82.g0.18O1.82. Zr0.82.a0.18O1.82. From the above analysis, it can be concluded that the stabilizing degrees of the four stabilizers in the descending order are CaO> MgO>Y2.3>CeO2.

关键词： c-ZrO2 empirical electron theory bond length difference valence electron structure properties

structure characterization of the oxide film on FGH96 superalloy powders with various oxidation degrees

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International Journal of Minerals,Metallurgy and materials 2024年第9期31卷 2037-2047页

作者： Yang liu Yufeng liu Sha {2. Lin {2. Peng {2. Shaorong {2. Na liu Zhou Li Xuanhui Qu Beijing Advanced Innovation center for materials Genome Engineering Institute for Advanced Materials and TechnologyUniversity of Science and Technology BeijingBeijing 100083China institute of materials Intelligent {2. Liaoning Academy of MaterialsShenyang 110004China Science and technology on Advanced High Temperature Structural materials Laboratory AECC Beijing Institute of Aeronautical MaterialsBeijing 100095China

The structure of the oxide film on FGH96 alloy powders significantly influences the mechanical properties of *** this study,FGH96 alloy powders with various oxygen contents were investigated using high-resolution transmission electron microscopy and atomic probe technology to elucidate the structure evolution of the oxide *** dispersive spectrometer analysis revealed the presence of two distinct components in the oxide film of the alloy powders:amorphous oxide layer covering the γ matrix and amorphous oxide particles above the *** alloying elements within the oxide layer showed a laminated distribution,with Ni,Co,Cr,and Al/Ti,which was attributed to the decreasing oxygen equilibrium pressure as oxygen diffused from the surface into the γ *** the other hand,Ti enrichment was observed in the oxide particles caused by the oxidation and decomposition of the carbide *** analysis of the oxide film with oxygen contents of 140,2.0,and 340 ppm showed similar element distributions,while the thickness of the oxide film varies approximately at 9,14,and 30 nm,*** findings provide valuable insights into the structural analysis of the oxide film on FGH96 alloy powders.

关键词： Ni-based superalloys surface structure oxide layer thickness oxidation behavior element distribution

Regulation of the pore structure of carbon nanosheets based electrocatalyst for efficient polysulfides phase conversions

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Journal of materials Science & technology 2024年第4期171卷 37-46页

作者： Xiaoyang liu Jingbo zhang Kangli liu Shijie zhang Rouhan Hou Xiaoyi Hu Peng zhang Guosheng Shao State center for International Cooperation on Designer Low-Carbon&Environmental materials(CDLCEM) School of Materials Science and EngineeringZhengzhou UniversityZhengzhou 450001China Zhengzhou materials Genome institute(ZMGI) Xingyang 450100China

The practical applications of lithium-sulfur(Li-S)batteries are hampered by the sluggish redox kinetics and polysulfides shuttle in the cyclic process,which leads to a series of problems including the loss of active materials and poor cycling *** this paper,the pore structures of carbon nanosheets based electrocatalysts were precisely controlled by regulating the content of water-soluble KCl *** relationship between pore structures and Li-S electrochemical behavior was studied,which demonstrates a key influence of pore structure in polysulfides phase *** the liquid-sloid redox reaction of polysulfides,the micropores and small mesopores(d2. nm)exhibited little impact,while the meso-pores(d>2. nm)and macropores played a decisive *** a typical exhibition,the nickel-embedded carbon nanosheets(Ni-CNS)with a high content of large mesopores and macropores can aid Li-S batteries in exhibiting stable cycling performance(760.1 mAh g^(-1)at 1 C after 300 cycles)and superior rate capac-ity(847.8 mAh g^(-1)at 2.C).Furthermore,even with high sulfur loading(8 mg cm^(−2.)and low electrolyte(E/S is around 6μL mg^(-1)),the high area capacity of 7.7 mAh cm^(−2.at 0.05 C could be *** work can provide a guideline for the design of the pore structure of carbon-based electrocatalysts toward high-efficiency sulfur species redox reactions,and afford a general,controllable,and simple approach to constructing high performance Li-S batteries.

关键词： Hierarchical porous carbon network Electrocatalyst Molten salt templating method Modified separators Li-S batteries

The Process of TiB_2.Cu composite Phase and structure Formation during Combustion Synthesis

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Journal of Wuhan University of technology(materials Science) 2006年第4期21卷 113-116页

作者：徐强 School of materials Science and Engineering Beijing Insitute of TechnologyBeijing 100081China

The reaction process of combustion synthesis for TiB2.-Cu was investigated in detail using combustion-wave arresting experiment, X-ray diffraction （ XRD ） analysis, SEM analysis and differential thermal analysis （ DTA ）. The XRD analysis results for the different parts of the quenched specimen show that TiCux intermetallic phase firstly forms with the propagation of combustion wave, and then Ti1.87 B50 and Ti3B4 metastable phases come forth due to the diffusion of B atoms and finally the stable TiB2.phase forms because of the continuous diffusion of B atoms. The formation of TiB2.phase is uot completed by one step, but undergoes several transient processes. The process of reaction synthesis for Ti-B-Cu ternary system can be divided into three main stages： melting of Cu and Ti , and the formation of Cu- Ti melt and few TiCux , TiBx intermetallic phases ; large numbers of TiCux intermetallic phases formation and some fine TiB2.particles precipitation ; and the TiB2.particles coarsening and the stable TiB2.and Cu two phases formation in the final product.

关键词： combustion synthesis reaction process TiB2.phase combustion-wave arresting experiment

Experimental investigation of engineered geopolymer composite for structural strengthening against blast loads

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Defence technology（防务技术） 2024年第2期32卷 496-509页

作者： Shan liu Chunyuan liu Yifei Hao Yi {2. Li Chen Zhan Li Key Laboratory of Coast Civil structure Safety of Ministry of Education Tianjin UniversityTianjin 300072China Tianjin Key Laboratory of Prefabricated Buildings and Intelligent Construction Hebei University of TechnologyTianjin 300400China institute of Defense Engineering AMSPLABeijing 100850China Engineering Research center of Safety and Protection of Explosion&Impact of Ministry of Education Southeast UniversityNanjing 211189JiangsuChina State Key Laboratory of Disaster Prevention&Mitigation of Explosion&Impact Army Engineering University of the PLANanjing 210007JiangsuChina

The recent increase in blast/bombing incidents all over the world has pushed the development of effective strengthening approaches to enhance the blast resistance of existing civil *** geopolymer composite(EGC)is a promising material featured by eco-friendly,fast-setting and strain-hardening characteristics for emergent strengthening and ***,the fiber optimization for preparing EGC and its protective effect on structural elements under blast scenarios are *** this study,laboratory tests were firstly conducted to evaluate the effects of fiber types on the properties of EGC in terms of workability,dry shrinkage,and mechanical properties in compression,tension and *** experimental results showed that EGC containing PE fiber exhibited suitable workability,acceptable dry shrinkage and superior mechanical properties compared with other types of *** that,a series of field tests were carried out to evaluate the effectiveness of EGC retrofitting layer on the enhancement of blast performance of typical *** tests include autoclaved aerated concrete(AAC)masonry walls subjected to vented gas explosion,reinforced AAC panels subjected to TNT explosion and plain concrete slabs subjected to contact *** was found that EGC could effectively enhance the blast resistance of structural elements in different *** AAC masonry walls and panels,with the existence of EGC,the integrity of specimens could be maintained,and their deflections and damage were significantly *** plain concrete slabs,the EGC overlay could reduce the diameter and depth of the crater and spallation of specimens.

关键词： Engineered geopolymer composites Fiber optimization Strengthening material Blast resistance Masonry wall Reinforced AAC panel Plain concrete slab

Optimum Design of Lightweight Silicon Carbide Mirror Assembly

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Journal of Wuhan University of technology(materials Science) 2008年第2期23卷 259-262页

作者： HAN Yuanyuan zhang Yumin HAN Jiecai zhang Jianhan YAO Wang ZHOU Yufeng center for composite {2. Harbin Institute of Technology Harbin 150080 China

According to the design requirement and on the basis of the principle that the thermal expansion coefficient of the support structure should match with that of the mirror, a lightweight silicon carbide primary mirror assembly was designed. Finite element analysis combined with the parameter-optimized method was used during the design. Lightweight cell and rigid rib structure were used for the mirror assembly. The static, dynamic and thermal properties of the primary mirror assembly were analyzed. It is shown that after optimization, the lightweight ratio of the silicon carbide mirror is 52.5%, and the rigidity of the silicon carbide structure is high enough to support the required mirror. When temperature changes, the deformation of the mirror surface is in proportion to the temperature difference.

关键词： silicon carbide mirror assembly optimum design finite element

Cooperative structure of Li/Ni mixing and stacking faults for achieving high-capacity Co-free Li-rich oxides

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Journal of Energy Chemistry 2024年第8期95卷 315-324,I0007页

作者： Zhen Wu Yu-Han zhang Hao Wang Zewen liu Xudong zhang Xin Dai Kunyang Zou Xiaoming Lou Xuechen Hu Lijing Ma Yan liu Yongning liu State Key Laboratory for Mechanical Behavior of materials Xi’an Jiaotong UniversityXi’an 710049ShaanxiChina Qingdao Industrial Energy Storage Research institute Qingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdao 266101ShandongChina Hefei Advanced Computing center Operation Management Corp Ltd Hefei 230088AnhuiChina center for High Performance Computing Network Information CenterXi’an Jiaotong UniversityXi’an 710049ShaanxiChina Wuhan Dongfeng Motor Corporation Ltd Wuhan 430056HubeiChina School of materials Science and Intelligent Engineering Nanjing UniversitySuzhou 215163JiangsuChina Key Laboratory of MEMS of the Ministry of Education Southeast UniversityNanjing 210096JiangsuChina International Research center for Renewable Energy State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong UniversityXi’an 710049ShaanxiChina

Co-free Li-rich layered oxides(LLOs)are emerging as promising cathode materials for Li-ion batteries due to their low cost and high ***,they commonly face severe structural instability and poor electrochemical activity,leading to diminished capacity and voltage ***,we introduce a Co-free LLO,Li_(1.167)Ni_(0.2.2.Mn_(0.611)O_(2.(Cf-L1),which features a cooperative structure of Li/Ni mixing and stacking *** structure regulates the crystal and electronic structures,resulting in a higher discharge capacity of 300.6 mA h g^(-1)and enhanced rate capability compared to the typical Co-free LLO,Li_(1.2.Ni_(0.2.Mn_(0.6)O_(2.(Cf-Ls).Density functional theory(DFT)indicates that Li/Ni mixing in LLOs leads to increased Li-O-Li configurations and higher anionic redox activities,while stacking faults further optimize the electronic interactions of transition metal(TM)3d and non-bonding O 2. ***,stacking faults accommodate lattice strain,improving electrochemical reversibility during charge/discharge cycles,as demonstrated by the in situ XRD of Cf-L1 showing less lattice evolution than *** study offers a structured approach to developing Co-free LLOs with enhanced capacity,voltage,rate capability,and cyclability,significantly impacting the advancement of the next-generation Li-ion batteries.

关键词： Co-free Li-rich oxides Li/Ni mixing Stacking faults Electronic structure

Microstructures,corrosion behavior and mechanical properties of as-cast Mg-6Zn-2.(Fe/Cu/Ni)alloys for plugging tool applications

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International Journal of Minerals,Metallurgy and materials 2024年第4期31卷 697-711页

作者： Baosheng liu Jiali Wei Shaohua zhang Yuezhong zhang Pengpeng Wu Daqing Fang Guorui Ma School of materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan 030024China State Key Laboratory for Mechanical Behavior of materials Xi’an Jiaotong UniversityXi’an 710049China Intelligent Equipment Research and Development center Zhuhai Institute of Advanced Technology Chinese Academy of SciencesZhuhai 519080China Advanced materials Research institute Zhuhai Dingmei Medical Technology Co.Ltd.Zhuhai 519000China

Mg-6Zn-2.(Fe/Cu/Ni)alloys were prepared through semi-continuous casting,with the aim of identifying a degradable magnesium(Mg)alloy suitable for use in fracturing balls.A comparative analysis was conducted to assess the impacts of adding Cu and Ni,which result in finer grains and the formation of galvanic corrosion *** electronic microscopy examination revealed that precipitated phases concentrated at grain boundaries,forming a semi-continuous network structure that facilitated corrosion penetration in Mg-6Zn-2.u and Mg-6Zn-2.i *** corrosion was observed in Mg-6Zn-2.e,while galvanic corrosion was identified as the primary mechanism in Mg-6Zn-2.u and Mg-6Zn-2.i *** the tests,the Mg-6Zn-2.i alloy exhibited the highest corrosion rate(approximately 932.9 mm/a)due to its significant potential *** testing showed that Mg-6Zn-2.i alloy possessed suitable ultimate compressive strength,making it a potential candidate material for degradable fracturing balls,effectively addressing the challenges of balancing strength and degradation rate in fracturing applications.

关键词： magnesium alloys microstructure micro-galvanic corrosion mechanical properties