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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 technology 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 technology 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

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

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

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

Toughening additive manufactured Zr-based bulk metallic glass composites by martensite phase transformation

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Journal of materials Science & technology 2024年第3期170卷 95-102页

作者： Pengcheng zhang Cheng zhang Jie Pan Di Ouyang Lin {2. State Key Laboratory of materials Processing and Die&Mould technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China

Additive manufacturing technology based on laser powder bed fusion(LPBF)offers a novel approach for fabricating bulk metallic glass(BMG)products without restriction in size and ***,the BMGs prepared by LPBF usually suffered from less plasticity and poorer fracture toughness as compared to their cast counterparts due to partial crystallization in heat-affected zones(HAZs).Since crystallization in HAZs is hard to avoid completely in LPBF BMGs,it is desirable to design a suitable alloy system,in which only ductile crystalline phase,instead of brittle intermetallics,is formed in *** unique structure could effectively increase the toughness/plasticity of the LPBF *** achieve this goal,a quaternary BMG system with a composition of Zr_(47.5)Cu_(45.5)Al_(5)Co_(2.is adopted and subjected to *** is found that nearly a single phase of B_(2.-ZrCu is precipitated in HAZs,while a fully amorphous phase is formed in molten pools(MPs).This B_(2.phase reinforced BMG {2. exhibits excellent mechanical properties with enhanced plasticity and ***,it is easy to modulate the mechanical properties by altering the amount of the B_(2.phase via adjusting the laser energy ***,the best combination of strength,plasticity,and notch toughness is obtained in the BMG {2. containing 2..4%B_(2.phase and 72.6%amorphous phase,which exhibits yield strength(σ_(s))of 142. MPa,plastic strain(ε_(p))of 4.65%,and notch toughness(K_(q))of 53.9 MPa m 1/***,a notable strain-hardening is also *** improvement of plasticity/toughness and appearance of strain-hardening behavior are mainly due to the martensite phase transformation from the B_(2.phase to the Cm phase during plastic deformation(i.e.,the phase transformation-induced plasticity effect).The current work provides a guide for making advanced BMGs and BMG {2.s by additive manufacturing.

关键词： Laser powder bed fusion Bulk metallic glass composites Phase transformation-induced plasticity Deformation mechanism

Highly-efficient CoRuO_(x)nanocatalysts for acidic oxygen evolution:The merit of optimum ordering degree of carbon nanotube support

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Particuology 2024年第7期90卷 470-477页

作者： Wenwen Li Yanni Wang Zhenzhen Zhao Meiqi liu Qing Liang Yuhua liu Fuxi liu Zhou Jiang Xu Zou Bingsen zhang Wei zhang Key Laboratory of Automobile materials MOE School of Materials Science&EngineeringJilin Provincial International Cooperation Key Laboratory of High-Efficiency Clean Energy MaterialsElectron Microscopy CenterInternational Center of Future ScienceJilin UniversityChangchun 130012China Shenyang National Laboratory for materials Science Institute of Metal ResearchChinese Academy of Sciences110016ShenyangChina

Hydrogen production from proton exchange membrane water electrolysis is constrained by the sluggish kinetics of the anodic oxygen evolution ***_(2.has attracted considerable attention due to its low reaction overpotential,but its inferior stability remains a major ***,a strategy is proposed to enhance the catalytic activity and stability of CoRuOx nanoparticles by doping Co and regulating the ordering degree of carbon nanotubes(CNTs)by air *** was found that the CoRuOx@CNTs-300 catalyst exhibited the best catalytic activity and stability when the annealing temperature was 300°*** the current density of 10 mA cm−2.the overpotential of this catalyst was only 2.1 mV,which was nearly 100 mV lower than that of commercial RuO_(2.(300 mV).Surprisingly,there was no significant increase in the overpotential when tested at a current density of 10 mA cm−2.for 50 *** density functional theory calculations indicate that the high activity of the catalyst is due to the electronic coupling of CoRuOx nanoparticles and CNTs,and that the introduction of Co and CNTs improves the electronic structure and solvation energies of the Ru in the active site,dramatically increasing the structural stability.

关键词： Electrocatalysis RuO_(2. CNTs Oxygen evolution reaction

Sequestration of helium and xenon via iron-halide compounds in early Earth

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Matter and Radiation at Extremes 2024年第3期9卷 83-88页

作者： Jurong zhang Hanyu liu Changfeng Chen Yanming Ma Key Laboratory of Material Simulation Methods and Software of Ministry of Education and State Key Laboratory of Superhard materials College of PhysicsJilin UniversityChangchun 130012China School of Physics and Electronics Shandong Normal UniversityJinan 250014China International center of Future Science Jilin UniversityChangchun 130012China Department of Physics and Astronomy University of NevadaLas VegasNevada 89154USA

The terrestrial abundance anomalies of helium and xenon suggest the presence of deep-Earth reservoirs of these elements,which has led to great interest in searching for materials that can host these usually unreactive ***,using an advanced crystal {2. search approach in conjunction with first-principles calculations,we show that several Xe/He-bearing iron halides are thermodynamically stable in a broad region of P–T phase space below 60 *** results present a compelling case for sequestration of He and Xe in the early Earth and may suggest their much wider distribution in the present Earth than previously *** findings offer insights into key material-based and physical mechanisms for elucidating major geological phenomena.

关键词： halide searching insight