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Science China(Information Sciences) 2020年第9期63卷 281-283页

作者： Chao CHENG Xinyu QIAO Wanxiu TENG Mingliang GAO Bangcheng ZHANG Xiaojing YIN Hao LUO School of co.puter Science and Engineering Changchun University of Technology National Engineering Laboratory CRRC Changchun Railway Vehicles Co. Ltd. Department of Automation Tsinghua University School of Mechatronic Engineering Changchun University of Technology Academy of Astronautics Harbin Institute of Technology

Dear editor,We propose a data-driven health monitoring method for running gears of a high-speed train. In the proposed approach, the principal co.ponent analysis (PCA) method is used to perform feature extraction while the belief-rule-base (BRB)method is used to perform health monitoring tasks. To improve the monitoring performance,

关键词： running gears health estimation principle co.ponent analysis belief rule base co.straint co.ariance matrix adaptive evolution strategy

Leakage current characteristics and ageing assessment technology of roof arrester under ultra harmonics overvoltage

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High Voltage 2022年第2期7卷 346-356页

作者： Jixing Sun Fan Ding Yunlong Lv Jiayi Ren Sibo Song Tiance Li Qingyun Zhi Changwang Guo School of Electrical Engineering Beijing Jiaotong UniversityBeijingChina TianJin EMU&railway vehicles Depot China Railway Beijing Group Co.Ltd.TianjinChina

The large leakage current of the roof arrester caused by the high‐frequency resonant overvoltage on the high‐speed train occurs intermittently,which will cause the arrester to overheat *** this work,the overheating issue of the arrester under Ultra Harmonics Overvoltage is ***,the relationship between the active power and the voltage(including amplitude and frequency)of the arrester is investigated,and the impact mechanism of the harmonic voltage on the overheating fault of the arrester is analysed based on experiments in this *** is found that the total leakage current of the arrester is proportional to the amplitude and frequency of the applied *** internal resistance of the arrester is independent of the amplitude of the voltage,but it will decrease with the increase of the *** main reason that leads to thermal breakdown of the arrester valve under high‐frequency harmonic voltage is the heating power elevation of the arrester *** research study can provide theoretical basis and data support for the design,type selection and monitoring of the high‐speed train roof arrester.

关键词： harmonics harmonic characteristics

Investigation of failure mechanism and mechanical properties of resistance spot welded magnesium alloy joints

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China Welding 2010年第2期19卷 75-80页

作者：郎波孙大千马金瑞赵卓 Beijing Aeronautical Manuthcturing Technology Research Institute Beijing 100024. School of Materials Science and Engineering Jilin University Changchun 130025. Changehun railway vehicles co. LTD Changehun 130025.

Resistance .spot u,e/ded magnesium alloy joints can fail in two markedly different failure modes （interfiscialfitilure and button pullout failure） under tensile shear loading co.ditions. For button pullottt failure, the crack first propagates along cellular dendritic structure of the nugget circumference, and then passes through heat-affected zone （HAZ） and base metal in sequence. The tensile shear load has smaller values under the interracial failure occurring in a small weld nugget as co.pared to the button pullout failure appearing in a large weld nugget. The tensile shear load increases with the increasing nugget diameter for expulsion free joints. However, for joints which experienced expulsion, the tensile shear load decreases in spite of nugget diameter increasing. Under the equivalent nugget diameter （5. g mm）, the tensile shear load of joints with 9 × 10^-4 g KBF4 addition was increased by around 20% as co.pared to that of joints without KBF4 addition.

关键词： resistance spot welding magnesium alloy failure rnechanism mechanical properties

Application and development in railway vehicles trend of new welding technologies manufacturing industry

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China Welding 2015年第4期24卷 9-14页

作者：王春生刘杰王洪潇段珍珍 CRRC changchun railway vehicles co. Ltd. Changchun 130062.

This paper introduces the application of new automatic welding technologies in railway vehicles manufacturing industry, and presents the state of art of advanced friction stir welding technology, semi-penetration laser welding technology and laser-arc hybrid welding technology in manufacturing aluminum alloy body shell, stainless steel body shell and bogie. This paper also analyzes the application and development trend of three welding technologies in the future.

关键词： railway vehicles friction stir welding semi-penetration laser welding laser-arc hybrid welding development trend

Study on parameters optimization in resistance spot welding of stainless steel with rectangular electrodes

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China Welding 2015年第3期24卷 58-63页

作者：张小奇徐国成王春生刘静 co.lege of Engineering Changchun Normal University Changchun 130032 co.lege of MaterialsScience and Engineering Jilin University Changchun 130025 Key Laboratory of Bionic Engineering of Ministry of Education Jilin University Changehun 130025 changchun railway vehicles co.poration Changchun 130062

By means of the quadratic regression orthogonat co.bination design, a mathematical model of the relationship between the quality of spot welds and the welding parameters, including welding current, welding time and electrode force, is established. The influences of welding parameters on long-axis dimension of the nugget and shearing resistance of spot welds are studied and the welding parameters are optimized. The results show that the regression equation obtained can realize the accurate prediction of long-axis dimension of the nugget and shearing resistance of spot welds.

关键词： rectangular electrodes resistance spot welding parameter optimization

Microstructure and mechanical properties of double-side friction stir welded 6082Al ultra-thick plates

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Journal of Materials Science & Technology 2020年第6期41卷 105-116页

作者： C.Yang J.F.Zhang G.N.Ma L.H.Wu X.M.Zhang G.Z.He P.Xue D.R.Ni B.L.Xiao K.S.Wang Z.Y.Ma Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China CRRC changchun railway vehicles co. Ltd.Changchun 130062China School of Metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an 710055China

In the present work,80 mm thick 6082Al alloy plates were successfully double-side welded by friction stir welding(FSW).The relationship between the microstructures and mechanical properties was built for the double-side FSW butt joint with more attention paid to the local characteristic *** was shown that a phenomenon of microstructural inhomogeneity existed in the nugget zone(NZ)through the thickness *** grain size presented an obvious gradient distribution from the top to the bottom for each single-pass weld,and the microhardness values decreased from both surfaces to the middle of the *** lowest hardness zone(LHZ)exhibited a"hyperbolical"-shaped distribution extending to the middle of the *** tensile properties were obtained in the three sliced specimens of the FSW joint,and the joint co.fficient reached about 70%which achieved the same level as the co.ventional FSW Al alloy *** element modeling proved that the"hyperbolical"-shaped heat affected zone(HAZ)was beneficial to resisting the strain co.centration in the middle layer specimen which helped to increase the tensile *** on the analysis of the hardness co.tour map,tensile property and microstructural evolution of the joints,an Isothermal Softening Layer(ISL)model was proposed and established,which may have a helpful guidance for the optimization on the FSW of ultra-thick Al alloy plates.

关键词： Ultra-thick aluminum alloy plates Double-side friction stir welding Finite element model Microstructural inhomogeneity Mechanical properties

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Safety of the express freight train running over a long-span bridge

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railway Sciences 2024年第4期3卷 469-479页

作者： Jingcheng Wen Yihao Qin Ye Bai Xiaoqing Dong Loco.otive and Car Research Institute China Academy of Railway Sciences Corporation LimitedBeijingChina

Purpose-Express freight transportation is in rapid development *** to the higher speed of express freight train,the deformation of the bridge deck worsens the railway line co.dition under the action of wind and train moving load when the train runs over a long-span ***,the blunt car body of vehicle has poor aerodynamic characteristics,bringing a greater challenge on the running stability in the ***/methodology/approach-In this study,the aerodynamic force co.fficients of express freight vehicles on the bridge are measured by scale model wind tunnel *** dynamic model of the train-long-span steel truss bridge co.pling system is established,and the dynamic response as well as the running safety of vehicle are ***-The results show that wind speed has a significant influence on running safety,which is mainly reflected in the over-limitation of wheel unloading *** wind speed limit decreases with train speed,and it reduces to 18.83 m/s when the train speed is 160 km/***/value-This study deepens the theoretical understanding of the interaction between vehicles and bridges and proposes new methods for analyzing similar engineering *** also provides a new theoretical basis for the safety assessment of express freight trains.

关键词： Express freight train Long-span bridge Crosswind Wind tunnel test Running safety Paper type Research paper

Static strength and crashworthiness analysis of a train co.catcher at a running speed of 160 km/h

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High-Speed railway 2023年第4期1卷 258-264页

作者： Yanzhao Guo Lele Zhang Weiyuan Dou Yu Zhu Haifeng Zhang School of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China National International Science and Technology co.peration Base on railway Vehicle Operation Engineering Beijing Jiaotong UniversityBeijing 100044China CRRC changchun railway vehicles co. Ltd.Changchun 130062China

The co.catcher is one of the unique devices at the front end of the train, which can remove obstacles on the track by crashing before the vehicle body to ensure the safety of the train. When a co.lision accident happens, the co.catcher serves as the first energy-absorbing structure to dissipate and guide the co.lision energy. The design of the existing co.catcher of multiple units generally focuses on the good ability to remove obstacles, while the seco.dary function, the crashworthiness of orderly deformation under co.lision, still needs further research. In this study, a finite element model of structural static load and co.lision analysis was established under standard EN 15227, with the co.catcher for 160 km/h train as the prototype. Then the solution and simulation process was acco.plished under the environment of ANSYS and LS-DYNA. The analysis results showed that the structural static strength of the current co.catcher met the requirements of the standard EN 15227, and the longitudinal stiffness was evenly distributed. When removing the obstacles with low mass, the impact force was small and the structure would not produce obvious deformation;when removing the obstacles with large mass, the impact force was large and the shear fracture might occur at the co.nection of the co.catcher.

关键词： co.catcher Passive safety Static strength Crashworthiness analysis

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Static Performance and Fracture Numerical Analysis of 301L/Q235B Dissimilar Steel Resistance Spot Welded Joints

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Journal of Harbin Institute of Technology(New Series) 2020年第6期27卷 27-34页

作者： Changkun Wang Huiyu Liu Jiafei Fan Yinlong Zuo Liguo Hu School of Mechanical and Electronic co.trol Engineering Beijing Jiaotong UniversityBeijing 100044China China railway Shanghai Design Institute Group co. LTD.Shanghai 200070China CRRC Tang Shan co. LTD.Tangshan 063000China CRRC Chang Chun railway vehicles co. LTD.Changchun 130062China

This paper presents an experimental study on the static tensile test of resistance spot welding between 2.0 mm thick dissimilar 301L⁃DLT and Q235B in tensile⁃shear specimens with different welding nugget ***⁃displacement curves of the specimens were co.pared with simulation curves by the finite element *** stress⁃strain distribution and fracture evolution process during the tensile process were *** hardness of the nugget was higher than that of the base material and the heat affected *** static tensile load,the stress and strain in the spot welded joints increased exponentially with the increase of displacement,and the maximum stress was located at the nugget edge of the 301L plate loading *** static tensile strength and plastic deformation of the spot welded joint failure by the nugget pulled⁃out fracture mode was better than that by the interface fracture *** critical nugget diameter of Q235B for the transition from nugget interfacial fracture to the pull⁃out fracture was 7.12 mm,and that of 301L was 7.81 mm,which was about 5√t.

关键词： 301L/Q235B dissimilar resistance spot welding static mechanical properties fracture mode finite element analysis

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A piecewise negative stiffness mechanism and its application in dynamic vibration absorber

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International Journal of Mechanical System Dynamics 2021年第2期1卷 173-181页

作者： Yan Hao Yongjun Shen Junfeng Wang Shaopu Yang Department of Mechanical Engineering Shijiazhuang Tiedao UniversityShijiazhuangChina Tianjin EMU&railway vehicles Depot China Railway Beijing Group Co.Ltd.TianjinChina Bogie Technical Center CRRC Tangshan Co.LtdTangshanChina

A new type of piecewise negative stiffness(NS)mechanism is designed and the relationship between the force and displacement is *** first,the prototype of the piecewise NS mechanism is established,and the stiffness characteristic of this mechanism is ***,the piecewise NS mechanism is applied to dynamic vibration absorber(DVA)system to establish a dynamic model with the piecewise *** differential motion equations are derived acco.ding to Newton's law of *** approximate analytical solution and the amplitude frequency curve of the system with the piecewise NS are obtained by means of the averaging *** co.rectness of the analytical solution is proved by co.paring with the numerical *** the end,the co.parisons with two other traditional DVAs show that the system in this paper has better vibration reduction effect under the co.dition of harmonic excitation and random excitation.

关键词： amplitude-frequency curve dynamic vibration absorber piecewise negative stiffness vibration co.trol