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Study of Debond Fracture Toughness of Sandwich composites with Metal Foam Core

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Journal of materials Science & Technology 2009年第5期25卷 713-716页

作者： Xinzhu Wang Linzhi Wu Shixun Wang Center for composite materials Harbin Institute of Technology Harbin 150001 China

Two types of experiments were designed and performed to evaluate the adhesive bond in metal foam composite sandwich structures. The tensile bond strength of face/core was determined through the flatwise tensile test （FWT）. The test results show that the interfacial peel strength is lower than the interlaminar peel strength in FWT test. The mode I interracial fracture toughness （GIC） of sandwich structures containing a pre-crack on the upper face/core interface is determined by modified cracked sandwich beam （MCSB） experiment. It is found that the crack propagates unsynchronously on the two side of the specimen and the propagation of interfacial debonding always stays on the face/core interface during the MCSB tests. In order to simulate the failure of metal foam composite sandwich structures, a computational model based on the Tsai-Hill failure criterion and cohesive zone model is used. By comparing with experiment results, it can be concluded that the computational model can validly simulate the interracial failure of metal foam composite sandwich structures with reasonable accuracy.

关键词： Interfacial fracture toughness Strain energy release rate Tsai-Hill failure criterion Cohesive zone model

Fabrication and Testing of Carbon Fiber Reinforced Truss Core Sandwich Panels

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Journal of materials Science & Technology 2009年第4期25卷 547-550页

作者： Bing Wang Linzhi Wu Li Ma Qiang Wang Shanyi Du Center for composite materials Harbin Institute of Technology Harbin 150001 China

Truss core sandwich panels reinforced by carbon fibers were assembled with bonded laminate facesheets and carbon fiber reinforced truss cores. The top and bottom facesheets were interconnected with truss cores. Both ends of the truss cores were embedded into four layers of top and bottom facesheets. The mechanical properties of truss core sandwich panels were then investigated under out-of-plane and in-plane compression loadings to reveal the failure mechanisms of sandwich panels. Experimental results indicated that the mechanical behavior of sandwich structure under in-plane loading is dominated by the buckling and debonding of facesheets.

关键词： Sandwich panel Truss core Carbon fiber

Fatigue Damage Accumulation of Steel/rubber composite

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Journal of materials Science & Technology 2006年第5期22卷 647-650页

作者： Zhenhui TIAN Huifeng TAN Xingwen DU Center for composite materials Harbin Institute of Technology Harbin 150001 China

The fatigue damage accumulation of [±20°] laminated steel cord reinforced rubber composite under T-T loading was studied. Results indicate that the increase in the cyclic maximum strain exhibits three-stage tendency in the process of fatigue. The macroscopic fatigue damage initiates from the ends of steel cords in the form of cylindrical crack. Damage propagates along with the increase in crack numbers, the cord/matrix interface debonding and the growth of interply cracks. By using the dynamic creep as parameter, a linear fatigue damage accumulation model was established. This model can be used under dual loading conditions to estimate the residual fatigue life of the specimen.

关键词： Rubber composites Fatigue Dynamic creep Damage accumulation

In situ construction of Cu(Ⅰ)-Cu(Ⅱ) pairs for efficient electrocatalytic nitrate reduction reaction to ammonia

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Journal of Energy Chemistry 2025年第1期 106-113页

作者： Muyun Zheng Yuchi Wan Leping Yang Shen Ao Wangyang Fu Zhengjun Zhang Zheng-Hong Huang Tao Ling Feiyu Kang Ruitao Lv State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and Engineering Tsinghua University institute of New Energy materials and Engineering School of Materials Science and Engineering Fuzhou University Key Laboratory of Advanced materials (MOE) School of Materials Science and Engineering Tsinghua University Key Laboratory for Advanced Ceramics and Machining Technology of Ministry of Education Tianjin Key Laboratory of Composite and Functional Materials School of Materials Science and Engineering Tianjin University

Electrocatalytic nitrate reduction reaction （NO3-RR） to ammonia under ambient conditions is expected to be a green process for ammonia synthesis and alleviate water pollution *** report a CuO nanoparticles incorporated on nitrogen-doped porous carbon （CuO@NC） catalyst for *** of Cu（Ⅱ） is reduced to Cu（Ⅰ） during the NO3-RR process to construct Cu（Ⅰ）-Cu（Ⅱ） pairs,confirmed by in situ X-ray photoelectron spectroscopy （XPS） and Raman *** functional theory （DFT） calculations indicated that the formation of Cu（Ⅰ） could provide a reaction path with smaller energy barrier for NO3-RR,while Cu（Ⅱ） effectively suppressed the competition of hydrogen evolution reaction （HER）.As a result,CuO@NC catalyst achieved a Faradaic efficiency of 84.2% at -0.49 V versus reversible hydrogen electrode （RHE）,and a NH3yield rate of 17.2 mg *** -0.79 V ***,higher than the HaberBosch process (<3.4 g h-1g-1cat.).This work may open a new avenue for effective NO3-RR by modulating oxidation states.

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Multi-dimensional Bi@C electrocatalyst for Cr3+/Cr2+ redox reaction boosting high-performance iron-chromium flow batteries

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Science China Chemistry 2025年

作者： Min Wu Mingjun Nan Shumin Liu Caihe Zhong Lin Qiao Huamin Zhang Xiangkun Ma Department of materials Science and Engineering Dalian Maritime University Division of Energy Storage Dalian National Laboratory for Clean Energy Dalian Institute of Chemical Physics Chinese Academy of Sciences

With the increasing demand for energy storage technology, iron-chromium flow batteries（ICFBs） have been widely concerned because of their price advantage. However, the low electrochemical activity of Cr3+/Cr2+redox couples and the side hydrogen evolution reaction limit the industrial application of ICFBs. A multi-dimensional Bi/carbon composite electrocatalyst（Bi@C）for ICFB is designed and prepared to improve the electrochemical activity of Cr3+/Cr2+redox couples. Benefiting by using the Bimetal organic framework（Bi-MOF） with solid matrix as precursors, Bi nanospheres are highly dispersed on the Bi@C electrocatalyst that effectively enhances the electrochemical activity. The special morphology of Bi@C electrocatalyst helps the transfer of electrons and ions, significantly reducing the polarization of battery. Herein, the 3D porous carbon frames accelerate mass transfer, and the 2D carbon nanobelts and carbon layer coating on 0D Bi nanospheres improve the conductivity of Bi nanospheres. Therefore, the ICFB with multi-dimensional Bi@C electrocatalyst exhibits coulombic efficiency of 98.10% and energy efficiency of 79.14% at 140 mA cm-2, which is higher than ICFBs with commercial graphite carbon electrocatalyst and with heat treatment carbon felt. This work provides a simple and economical method to fabricate a high-performance multidimensional Bi@C electrocatalyst for Cr3+/Cr2+redox couples, boosting the development of ICFBs.

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Measurement of large deformation of nylon cord-rubber composite and effects of perpendicular loads on its stress-strain behaviors

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Journal of Harbin institute of Technology(New Series) 2003年第1期10卷 34-38页

作者：张丰发杜星文于增信 Center for composite materials Harbin Institute of Technology

Effects of transverse loads on longitudinal stress strain behaviors and longitudinal constant tensile loads on transverse stress strain behaviors of single ply of nylon cord rubber composite are studied respectively under biaxial tensile condition with cruciform specimen. Effects of transverse constant tensile load on longitudinal tensile mechanical properties are indistinctive compared with corresponding uniaxial longitudinal tensile mechanical properties. It can be relative to larger difference between longitudinal and transverse mechanical properties. Its dominating failure mode is typical fiber dominated mode; However, Experiment results indicate that transverse mechanical properties of nylon cord rubber composite with longitudinal constant tensile loads are distinct from its uniaxial transverse tensile mechanical properties. It can be attribute to action of longitudinal tension that makes material rigidify in the direction perpendicular to fiber, Mode of failure is representative of matrix dominated failure. For the measurement of large deformation up to 50 percent, a special CCD imaging method is employed in the experimental investigation that makes measurement of large deformations more precise.

关键词： nylon cord rubber composite cruciform specimen large deformation biaxial tensile condition

Thermal deformation analysis of the composite material satellite antenna

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Journal of Harbin institute of Technology(New Series) 2007年第5期14卷 609-612页

作者：王玮杜星文周振功 Center for composite materials Harbin Institute of Technology

Controlling the thermal deformation is a crucial index for the design of the satellite antenna. To calculate and measure the satellite antenna’s thermal deformation is also an important step for the design of satellite antenna. Based on the foundation of equivalent assumption, the thermal deformation of the parabolic satellite antenna was analyzed by the finite element method for different design project. The best design project that had the minimum of the thermal deformation could be obtained through changing the lay-angle, lay-layers and lay-thickness of each layer. Results show the asymmetry structure has the minimum of thermal deformation. This paper may provide useful information for the further investigation on the coupling of thermal-stress structure.

关键词： thermal deformation lay-angle lay-layers lay-thickness parabolic satellite antenna

Effect of pre-oxidation on strength and thermal shock behavior of ZrB_2-SiC-graphite ceramic composites

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Journal of Harbin institute of Technology(New Series) 2012年第1期19卷 12-16页

作者：刘洋梁军 Center for composite materials Harbin Institute of Technology

A novelty technique,namely,pre-oxidation,has been proposed to improve the strength and thermal shock behavior of ZrB2-SiC-graphite ceramic composites,which is a promising candidate for ultra-high temperature ceramics (UHTCs) in aerospace engineering. The composite is pre-oxidized at temperatures of 900 ℃ and 1100 ℃ for 1 h and 3 h in air. A theoretical model considering surface heat transfer has been given and analyzed. A water-quenching technique is adopted at different temperatures from 300 ℃ to 600 ℃ in order to investigate the thermal shock behavior of pre-oxidized composites. The critical thermal shock temperature improves more than 40% after pre-oxidizing at 1100 ℃ for 3 h. However,the composites strength is not improved as a result of the insensitivity to surface defects.

关键词： UHTCs thermal properties thermal shock pre-oxidation strength

INVESTIGATION OF THE SCATTERING OF HARMONIC ELASTIC WAVES BY TWO COLLINEAR SYMMETRIC CRACKS USING THE NON-LOCAL THEORY

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Applied Mathematics and Mechanics(English Edition) 2001年第7期22卷 766-775页

作者： ZHOU Zhen-gong(周振功) WANG Biao(王彪) Center for composite materials Harbin Institute of Technology Harbin 150001 P R China Center for Composite Materials Harbin Institute of Technology Harbin 150001 P R China

The scattering of harmonic waves by two collinear symmetric cracks is studied using the non-local theory. A one-dimensional non-local kernel was used to replace a two-dimensional one for the dynamic problem to obtain the stress occurring at the crack tips. The Fourier transform was applied and a mixed boundary value problem was formulated. Then a set of triple integral equations was solved by using Schmidt's method. This method is more exact and more reasonable than Eringen's for solving this problem. Contrary to the classical elasticity solution, it is found that no stress singularity is present at the crack tip. The non-local dynamic elastic solutions yield a finite hoop stress at the crack tip, thus allowing for a fracture criterion based on the maximum dynamic stress hypothesis. The finite hoop stress at the crack tip depends on the crack length, the lattice parameter and the circular frequency of incident wave.

关键词： the non-local theory Schmidt's method the triple-integral equation