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Fatigue Crack Growth Behavior of Different Zones in an Annealed Automatic Gas Tungsten Arc Weld Joint of TA16 and TC4 Titanium Alloys

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Journal of Wuhan University of technology(Materials Science) 2020年第6期35卷 1090-1097页

作者： SHAO Ling WU Sujun PENG Wenya DATYE Amit JU Hongbo LIU Ying Research Institute of Zhejiang University-Taizhou Zhejiang UniversityTaizhou 318000China School of Materials Science and Engineering Beihang UniversityBeijing 100191China AECC Hunan Aviation Powerplant Research Institute Zhuzhou 412000China Department of Mechanical Engineering&Materials Science Yale UniversityNew HavenCT 06511USA Key Laboratory of Advanced Welding technology of Jiangsu Province Jiangsu University of Science and TechnologyZhenjiang 212003China Institute of technology of Aircraft Engine Beijing Research Institute of Aviation EngineeringBeijing 100024China

Based on the investigated microstructure of different zones in the annealed automatic gas tungsten arc weld joint of TA16 and TC4 titanium alloys,the mechanical property of them was assessed under fatigue crack growth rate *** evaluation of fatigue crack growth rate,three points bending specimens were *** correlation between the range of stress intensity factor and crack growth rate was determined in different zones of the annealed weld *** crack growth rates were obviously different in different zones of weld joint of dissimilar titanium alloys,due to their different *** electron microscope examinations were conducted on the fracture surface in order to determine the relevant fracture mechanisms and crack growth mechanisms with respect to the details of microstructure.

关键词： dissimilar titanium alloys joining weld joint microstructure fatigue crack growth rate fracture

Application of Super-Synchronization Speed Control technology in Two 80 MVA Motor-Generator Units of HL-2A

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Plasma Science and technology 2007年第2期9卷 231-234页

作者：李华俊杜沧宣伟民彭建飞胡浩天刘伶康利徐丽荣黄昭荣王芬王小平 Southwestern Institute of Physics Chengdu 610041China Beijing New Metallurgy Electric Co. Ltd.China

Two sets of super-synchronization speed control assemblies for two 80 MVA motor-generator units have been developed successfully in order to satisfy the demand of the toroidal field system in the HL-2A tokamak. Based on the three-phase logical no-circumfluence a.c./a.c. cycloconverter, the speeds of two 2500 kW double fed drive motors have been regulated by means of the vector control technology. The maximum operating speed of each motor- generator unit has been raised from 1488 rpm （revolutions per minute） to 1650 rpm and the released energy of each unit during a pulsed discharge can reach 500 MJ. As a result, the toroidal field system has the capacity to provide 2.8 tesla （T） in HL-2A experiments.

关键词： double fed motor a.c./a.c cycloconverter vector control super-synchro nization speed control assembly

Preparation and Microstrutures of BSTO/MgO Ferroelectric Materials for Phase Shift

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Journal of Wuhan University of technology(Materials Science) 2007年第1期22卷 122-125页

作者：杨春霞 College of Materials Science and Engineering Nanjing University of Technology

Barium strontium titanate/magnesia （BSTO/MgO） ferroelectric material for phase shift was prepared by traditional solid phase synthesis. The phase distribution, microstructure and electric properties were investigated. The results show that no secondary phase appears in the composites and the dimension of grains distributes uniformly. With 50 wt% MgO content, the dielectric tunability reaches 17.5 % in the external DC field of 4 000 Vomm^-1 and the microwave loss at about 2.5 GHz is 8×10^-3. Hence, it can be applied in tunable microwave phase shifters.

关键词： barium strontium titanate/magnesia ferroelectric material phase shifter dielectric

Influence of Mg5Ga2 compound on microstructures and electrochemical properties of Mg-5%Hg-22%Ga alloy

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Progress in Natural Science:Materials International 2011年第1期21卷 73-79页

作者： Yan FENG~1,Ri-chu WANG~1,Chao-qun PENG~1,Hui-ping TANG~2,Hai-yan LIU~2 1.School of Materials Science and Engineering,Central South University,Changsha 410083,China 2.Northwest Institute for Non-ferrous Metals Research,Xi'an 710016,China [a] School of Materials Science and Engineering Central South University Changsha 410083 China [b] Northwest Institute for Non-ferrous Metals Research Xi'an 710016 China

The Mg-5%Hg-22%Ga（mole fraction） alloy was *** at 573-673 K for different times was carried out to ensure the fine dispersion of the *** electron microscopy（SEM）,X-ray diffractometry（XRD） and energy spectrum analysis（ESA） were employed to characterize the microstructures and phases of the Mg-5%Hg-22%Ga *** electrochemical and corrosion behaviors of the above alloy were studied by potentiodynamic,galvanostatic and electrochemical impedance spectroscopy（EIS） *** relationship between the Mg5Ga2compound and the electrochemical properties of the Mg-5%Hg-22%Ga alloy was *** results demonstrate that the heat treatment at 573-673 K for 24 h accelerates the growth of the intergranular eutectic Mg-Mg5Ga2and the heat treatment for 200 h prompts the transition of eutectic to dispersed linear Mg phase and *** transition enhances the electrochemical activity and corrosion resistance of the Mg-5%Hg-22%Ga *** the galvanostatic tests with current density of 100 mA/cm2,the most negative potential,-1.991 V, occurs in the sample aged for 200 *** largest corrosion current density of 44.36 mA/cm2occurs in the sample aged for 24 h.

关键词： Mg-Hg-Ga alloys anodic behavior Mg5Ga2 phase intergranular corrosion

Imaging System and Plasma Imaging on HL-2A Tokamak

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Plasma Science and technology 2004年第4期6卷 2353-2358页

作者：郑银甲冯震罗萃文刘莉李伟严龙文杨青巍刘永 Southwestern Institute of Physics Chengdu 610041China Southwestern Institute of Physics Chengdu 610041Chinas a new diagnostic means plasma-imaging system has been developed on the HL-2A tokamak with a basic understanding of plasma discharge scenario of the entire torus checking the plasma position and the clearance between the plasma and the first wall during discharge. The plasma imaging system consists of (1) color video camera (2) observation window and turn mirror (3) viewing & collecting optics (4) video cable (5) Video capture card as well as PC. This paper mainly describes the experimental arrangement plasma imaging system and detailed part in the system along with the experimental results. Real-time monitoring of plasma discharge process particularly distinguishing limitor and divertor configuration the imaging system has become key diagnostic means and laid the foundation for further physical experiment on the HL-2A tokamak.

As a new diagnostic means, plasma-imaging system has been developed on the HL-2A tokamak, with a basic understanding of plasma discharge scenario of the entire torus, checking the plasma position and the clearance between the plasma and the first wall during discharge. The plasma imaging system consists of (1) color video camera, (2) observation window and turn mirror, (3) viewing & collecting optics, (4) video cable, (5) Video capture card as well as PC. This paper mainly describes the experimental arrangement, plasma imaging system and detailed part in the system, along with the experimental results. Real-time monitoring of plasma discharge process, particularly distinguishing limitor and divertor configuration, the imaging system has become key diagnostic means and laid the foundation for further physical experiment on the HL-2A tokamak.

关键词： plasma imaging HL-2A visible emission

Determination of Water Diffusion Coefficients and Dynamics in Adhesive/Carbon Fiber Reinforced Epoxy Resin Composite Joints

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Chemical Research in Chinese Universities 2007年第4期23卷 474-478页

作者： WANG Chao WANG zhi WANG Jing SU Tao Heilongiang Petrochemistry Institute Harbin 150040 P. R. China Key Laboratory of Molecular Enzymology and Engineering of Ministry of Education Jilin University Changchun 130023 P. R. China

To determinate the water diffusion coefficients and dynamics in adhesive/carben fiber reinforced epoxy resin composite joints, energy dispersive X-ray spectroscopy analysis（EDX） is used to establish the content change of oxy- gen in the adhesive in adhesive/carbon fther reinforced epoxy resin composite joints. As water is made up of oxygen and hydrogen, the water diffusion coefficients and dynamics in adhesive/carben fiber reinforced epoxy resin composite joints can be obtained from the change in the content of oxygen in the adhesive during humidity aging, via EDX analy-sis. The authors have calculated the water diffusion coefficients and dynamics in the adhesive/carbon fiber reinforced epoxy resin composite joints with the aid of beth energy dispersive X-ray spectroscopy and elemental analysis. The de- termined results with EDX analysis are almost the same as those determined with elemental analysis and the results al- so show that the durability of the adhesive/carbon fther reinforced epoxy resin composite joints subjected to silane cou- pling agent treatment is better than those subjected to sand paper burnishing treatment and chemical oxidation treat- ment.

关键词： Diffusion coefficient Dynamics Energy dispersive X-ray spectroscopy Elemental analysis Adhesive/ carbon fiber reinforced epoxy resin composites joint

Simulations of ultra-long wavelength interferometers in Earth orbit and on the lunar surface

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Research in Astronomy and Astrophysics 2015年第3期15卷 443-452页

作者： Mo Zhang Mao-Hai Huang Yi-Hua Yan Key Laboratory of Space Astronomy and technology National Astronomical ObservatoriesChinese Academy of Sciences Key Laboratory of Solar Activity National Astronomical Observatories Chinese Academy of Sciences

We present simulations of interferometers in Earth orbit and on the lunar surface to guide the design and optimization of space-based ultra-long wavelength missions, such as those pioneered by China＇s Chang＇e Program. We choose parame- ters and present simulations using simulated data to identify inter-dependencies and constraints on science and engineering parameters. A regolith model is created for the lunar surface array simulation, and the results show that the lunar regolith will have an undesirable effect on the observations. We estimate data transmission requirements, calculate sensitivities for both cases, and discuss the trade-off between brightness tem- perature sensitivity and angular resolution for the Earth orbit array case.

关键词： techniques: interferometric -- Moon -- methods: data analysis

Slip-Control Strategy of Dual Independent Electric Drive Tracked Vehicle

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Journal of Beijing Institute of technology 2019年第4期28卷 715-724页

作者： Shuyang Zhang Yunan Zhang Keyan Ning Nanming Yan Qingfeng Fang Weaponry and Control Department Army Academy of Armored ForcesBeijing 100072China China North Vehicle Research Institute Beijing 100072China

In order to improve the brake performance of a dual independent electric drive tracked vehicle,a dynamic model for braking situation was ***,a sliding model controller(SMC)with an auxiliary system was designed to control the slip and its effectiveness was proved.A hardware-in-loop simulation through MATLAB/XPC was compared with the normal SMC and normal integral sliding mode controller(ISMC),the results show that SMC with the auxiliary system has a better performance:a smaller overshoot and steady state *** disturbance is suppressed *** the initial speed of ***/h,the brake distance was shortened by 3.4%and 6.8%compared with the other two methods,***,initial speeds of ***/h tests was carried out on a flat soil *** with a no-control brake,the displacement was shortened by *** demonstrates the effectiveness of the slip-control *** the same situation,the error between the simulation and test is 18.1%,which validates the accuracy of models.

关键词： tracked vehicle electric drive braking slip sliding model control

First principles study of behavior of helium at Fe(110)-graphene interface

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Chinese Physics B 2021年第4期30卷 432-437页

作者： Yan-Mei Jing Shao-Song Huang Key Laboratory of Material Modification by Laser Ion and Electron Beams(Dalian University of Technology)Ministry of EducationDalian 116024China

Recently,metal-graphene nanocomposite system has aroused much interest due to its radiation tolerance ***,the related atomic mechanism for the metal-graphene interface is still ***,stainless steels with Fe as main matrix are widely used in nuclear ***,in this study,the atomic behaviors of point defects and helium(He) atoms at the Fe(110)-graphene interface are investigated systematically by first principles *** results indicate that graphene interacts strongly with the Fe(110) *** comparison with those of the original graphene and bulk Fe,the formation energy values of C vacancies and Fe point defects decrease significantly for Fe(110)-***,as He atoms have a high migration barrier and large binding energy at the interface,they are trapped at the interface once they enter into *** theoretical results suggest that the Fe(110)-graphene interface acts as a strong sink that traps defects,suggesting the potential usage of steel-graphene with multiply interface structures for tolerating the radiation damage.

关键词： Fe(110)-graphene helium interface first principles calculations