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Research on an innovative structure of an open-ribbed steel-ultra-high performance concrete composite bridge deck

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Frontiers of Structural and Civil Engineering 2024年第5期18卷 716-730页

作者： Xudong SHAO Xuan SUN Deqiang ZOU Junhui CAO Chuanqi YANG School of Civil Engineering Hunan UniversityKey Laboratory for Wind and Bridge Engineering of Hunan ProvinceChangsha 410082China China construction Fifth Engineering Division co. Ltd.Changsha 410004China

To completely solve the problem of fatigue cracking issue of orthotropic steel bridge decks(OSDs),the authors proposed a steel–ultra-high performance concrete(UHPC)lightweight composite deck(LWCD)with closed ribs in *** on the successful application of that LWCD,an adaptation incorporating an innovative composite deck structure,i.e.,the hot-rolled section steel–UHPC composite deck with open ribs(SSD)is proposed in this paper,aiming to simplify the fabrication process as well as to reduce the cost of *** on a long-span cable-stayed bridge,a design scheme is proposed and is compared with the conventional OSD ***,a finite element(FE)calculation is conducted to reflect both the global and local behavior of the SSD scheme,and it is found that the peaked stresses in the SSD components are less than the corresponding allowable values.A static test is performed for an SSD strip specimen to understand the anti-cracking behavior of the UHPC layer under negative bending *** static test results indicate that the UHPC layer exhibited a satisfactory tensile toughness,the UHPC tensile strength obtained from the test is 1.8 times the calculated stress by the FE model of the real *** addition,the fatigue stresses of typical fatigue-prone details in the SSD are calculated and evaluated,and the influences of key design parameters on the fatigue performance of the SSD are *** to the fatigue results,the peaked stress ranges for all of the 10 fatigue-prone details are within the corresponding constant amplitude fatigue *** a fatigue test is carried out for another SSD strip specimen to explore the fatigue behavior of the fillet weld between the longitudinal and transverse *** specimen failed at the fillet weld after equivalent 47.5 million cycles of loading under the design fatigue stress range,indicating that the fatigue performance of the SSD could meet the fatigue design *** calculations and experim

关键词： steel-ultra-high performance concrete composite deck open rib strip model test static and fatigue performance orthotropic steel deck

Effect of Deposition Temperature on Dynamics and Mechanism of Deposition for Si-B-C Ceramic from BCl_3/SiCH_3Cl_3/H_2 Precursor

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Journal of Materials Science & Technology 2012年第9期28卷 793-798页

作者： Xinzhang Zuo Litong Zhang Yongsheng Liu Siwei Li Laifei Cheng National Key Laboratory of Thermostructure composite Maateials Northwestern-Polytechnical UniversityXi'an 710072China

The deposition rate, phase, chemical composition and microstructure of deposits were determined from 950 to 1100 ℃. With increasing temperature, the deposition rate increases, and the morphology changes from smooth to coarse, meanwhile, the concentration of silicon increases while that of boron decreases. The deposition process is controlled by chemical reactions, and the activation energy is 271 kJ/mol. At relatively lower temperature （below 1000 ℃）, the deposition process is dominated by formation of BaC. While at higher temperature （above 1000 ℃）, it is governed by formation of SiC. BaC and SiC disperse uniformly in the Si-B-C co-deposition system and form a dense network structure.

关键词： Si-B-C ceramic Chemical vapor deposition (CVD) Deposition mechanism Morphology

M2M’AlB4（M = Mn, Fe, co, M’ = Cr, Mo, W）: Theoretical predicted ordered MAB phases with Cr3AlB4 crystal structure

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Journal of Materials Science & Technology 2019年第7期35卷 1432-1438页

作者： Fu-Zhi Dai Huimin Xiang Yinjie Sun Yanchun Zhou Science and Technology on Advanced Functional composite Laboratory Aerospace Research Institute of Materials & Processing Technology

The nanolaminated MAB phases have attracted great research interests due to their unusual combination of metal-like and ceramic-like properties, which is similar to MAX phases. Recently, ordered quaternary MAX phases have been discovered, which enriches the family of MAX phases, and opens a new window to tailor the properties of MAX phases and to develop new MXenes. In the present work, we explored possible ordered quaternary MAB phases with Cr3AlB4 structure(space group: Pmmm) by first-principles calculations. The predictions show that M2M’AlB4 phases with M = Mn, Fe, co and M’ = Cr, Mo, W exhibit strong tendency of ordering, where M locates at 2t site(0.5, 0.5, z2t) and M’ locates at 1 g site(0, 0.5,0.5). The main driving force of ordering may be the differences in bonding strengths between Al and M elements. Analyses on chemical bonds reveal that bonding strengths increase following the order:Al-Mn co, which is consistent with the prediction that ordering tendency increases when M changes from Mn to co, as derived from enthalpy differences. The ordered M2M’AlB4 phases with M =Mn or Fe are predicted ferromagnetic and ordered M2M’AlB4 phases display lower shear resistance and possibly better ductility in comparison to Cr3AlB4.

关键词： MAB phase Ordered structure First-principle calculations Cr3AlB4 Chemical bonds Ultrahigh temperature ceramics

Robotic compliant assembly for complex-shaped composite aircraft frame based on Gaussian process considering uncertainties

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Chinese Journal of Aeronautics 2024年第10期37卷 471-482页

作者： Yingke YANG Dongsheng LI Yunong ZHAI Jie WANG Lei XUE Zhiyong YANG School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China Ningbo Institute of Technology Beihang UniversityNingbo 3158002China coMAC Shanghai Aircraft Manufacturing co. Ltd.Shanghai 201324China

Robots are finding increasing application in aircraft composite structure assembly due to their flexibility and the growing demand of aircraft manufacturers for high production *** contact force of the composite frame in a robotic assembly of the aircraft composite fuselage panel can hardly be controlled due to the multi-surface variable contact stiffness caused by compliance and complex shape with multiple mating *** paper proposes a robotic assembly system for the aircraft composite fuselage frame with a compliant contact force control strategy using the Gaussian process surrogate ***,a robotic assembly system is introduced,and the global coordinate system transformation model is ***,a compliant force control architecture is designed to generate the desired output ***,a Gaussian process surrogate model with uncertainties is utilized to model the complicated relationship between the robot’s output force and the normal contact force acting on the mating surface of the composite ***,an optimal contact force control strategy is implemented to improve the contact ***,an experiment demonstrates that the proposed methodology can ensure that the contact force on each surface is within the limit of the engineering specification and uniformly distributed,improving the quality compared to the traditional assembly process.

关键词： Aircraft composite structure assembly Multi-surface contact compliant control Gaussian process Uncertainty

Highly effective direct synthesis of DMC from CH_3OH and co_2 using novel Cu-Ni/C bimetallic composite catalysts

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Chinese Chemical Letters 2009年第3期20卷 352-355页

作者： Jun Bian Min Xiao Shuan Jin Wang Yi Xin Lu Yue Zhong Meng State Key Laboratory of Optoelectronic Materials and Technologies~Institute of Optoelectronic and Functional composite Materials Sun Yat-Sen University Guangzhou 510275 PR China Department of Chemistry & Medicinal Chemistry Program Office of Life Sciences National University of Singapore 3 Science Drive 3 Singapore 117543 Republic of Singapore

Novel Cu-Ni/C has been prepared and utilized as an efficient catalyst system in direct synthesis of DMC from CH3OH and co2.

关键词： Dimethyl carbonate Carbon dioxide Bimetallic catalyst Catalysis

Micromechanical behavior of TiNb/NiTi composite during a pre-straining process:an in situ synchrotron investigation

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Rare Metals 2023年第1期42卷 263-272页

作者： Shun Guo Wang Ding Ting-Hui Wu Wen Ma Bao-Guo Shen Hai-Xia Liu Xiao-Nong Cheng School of Materials Science and Engineering Jiangsu UniversityZhenjiang212013China Youke Publishing co. LtdGrinm Group Co.LtdBeijing100088China Zhenjiang Key Laboratory of UAV Application Technology Jiangsu Aviation Technical CollegeZhenjiang212134China

The micromechanical behavior of a recently developed TiNb/NiTi composite during a pre-straining process was investigated to broaden the understanding of deformation mechanisms of the martensitic-transforming *** was found that during loading,besides inherent elastic elongation,the TiNb/NiTi composite also experienced two different categories of stress-induced martensitic transformations(SIMTs,including B2→B19’andβ→α")and slight plastic *** the following unloading,this composite recovered elastically,and underwent simultaneously a fully reversibleα"→βSIMT as well as a partially reversible B19’→B2 *** was the incomplete B19’→B2 SIMT and the permanent plastic deformation that led to the~4.6%macroscopic residual strain after *** the entire loading-unloading procedure,the growth and shrinkage of(001)compound twins in B19’martensite also contributed to the large nearlinear-elastic deformation of the present composite.

关键词： Metal matrix composites Mechanical properties Phase transitions Synchrotron radiation

Characteristic investigation of trilayered Cu/Al8011/Al1060 composite:Interface morphology, microstructure, and in-situ tensile deformation

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Progress in Natural Science:Materials International 2021年第5期31卷 679-687页

作者： Mahmoud Ebrahimi Guoping Liu Chuanwei Li Qudong Wang Haiyan Jiang Wenjiang Ding Fengling Su Zhengping Shang National Engineering Research Center of Light Alloy Net Forming and Key State Laboratory of Metal Matrix composites School of Materials Science and EngineeringShanghai Jiao Tong University Institute of Materials Modification and Modeling School of Materials Science and Engineering Shanghai Jiao Tong University Sichuan Winner Special Electronic Materials co. Ltd. jiangsu Zhongse composite Materials co. Ltd.

In this work, Cu/Al8011/Al1060 trilayered composite with an ultrathin copper layer was fabricated successfully by the hybrid process of cast-rolling and hot-roll-bonding. The effects of heat treatment were investigated on the microstructure and mechanical behavior of the composite. The results showed that annealing temperatures above 300°C led to the formation of new intermetallic compounds that joined their initial counterparts. Also, the interface growth was fast above 340°C. It was found that the annealing temperature of 320°C led to the optimal tensile properties of the composite. Through rolling, hard-brittle IMCs imposed intense plastic strains on the surrounding regions, resulting in further grain refinement of both metals in the vicinity of the interface. Although the kernel average misorientation of the trilayered composite was almost identical with the Cu/Al8011 bimetal,its amount was considerably decreased after heat treatment, as the distorted structure changed into a nearly strain-free one using the restoration phenomenon. The SEM-based in-situ tensile test showed that crack initiation occurred within the IMCs and propagated into the Cu strip, leading to its early fracture. However, the strengthdisplacement curve during in-situ tensile deformation did not decrease significantly due to the ultrathin copper layer.

关键词： Heat-treatment Intermetallic compounds Mechanical properties Kernel average misorientation Microstructure analysis Crack initiation

Preparation of pH-sensitive composite Nanofiltration Membrane

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Journal of Wuhan University of Technology(Materials Science) 2010年第1期25卷 44-48页

作者：刘建立王薇 Key Laboratory of Hollow fiber Membrane Materials and Membrane Process Tianjin Polytechnic University Tianjin Motian Membrane Engeering and Technology co. Ltd.

Positively charged composite nanofiltration （NF） membranes were prepared through interfacial polymerization of poly[2-（N,N-dimethyl amino）ethyl methacrylate]（PDMAEMA） on porous polysulfone （PSF） substrate membranes. The effects of pH on swelling ratio （SR） of the pure crosslinked PDMAEMA membrane and on separation performances of the composite NF membrane were investigated. The results show that the quaternized amino groups produced through interfacial polymerization technique are soluble in both phases, which accelerate the crosslinking reaction as self-catalysts. The swelling/contracting behavior of the pure crosslinked PDMAEMA exhibited a well reversible pH sensitive property. Importantly, the rejection and flux of the composite NF membrane show pH-sensitive behavior in NF process. Furthermore, with the help of a relatively novel method to measure membrane conduction, the true zeta potentials calculated on the basis of the streaming potential measurements proved the pH-sensitive behavior of the NF membrane.

关键词： polymer hydrogels intelligent membrane nanofiltration membrane charged membrane pH-sensitivity

Tribological properties of Al-GNP composites at elevated temperature

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Friction 2024年第5期12卷 1028-1041页

作者： Sunil POUDEL Rizwan BAJWA Yongde XIA Zakir KHAN Yi ZHANG Yanqiu ZHU college of Engineering Mathematics and Physical SciencesUniversity of ExeterExeterEX44QFUK European Technical Centre Daido Metal Co.Ltd.Iliminster SomersetTA199PHUK

Lighter and more powerful next generation vehicles and other rotary machinery demand bearings to operate in harsher conditions for higher efficiency,and the continuous development of advanced low-wear and friction materials is thus becoming even more important to meet these *** aluminium composites reinforced with high performance lubricate phases such as graphene nanoplatelets(GNPs)are very promising and have been vigorously *** maintaining a low coefficient of friction(coF)and offering great strength against wear due to their self-lubricating capability,the solid lubricant like GNPs protect the bearing surface from wear damage and prevent change in metallurgical properties during temperature *** paper first studies the high-temperature tribological performance of aluminium matrix composites reinforced with GNP,consolidated via powder metallurgy,then elucidates their tribological *** report that the best tribological performance is achieved by the composite containing 2.0 wt%GNP,with an extraordinarily low coF of 0.09 and a specific wear rate of 3.5×10^(−2)mm^(3)·N^(−1)·m^(−1),which represent 75%and 40%reduction respectively,against the plain aluminium consolidated under identical *** in-track and out-of-track Raman analysis have confirmed the role of GNPs in creating a tribofilm on the counterpart surface which contributed to the excellent performance.

关键词： nanocomposite graphene nanoplatelet(GNP) tribology powder metallurgy