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Hydrogen absorption behavior of TA15 alloy

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International Journal of Minerals,Metallurgy and Materials 2011年第2期18卷 210-215页

作者： Xue-ping Ren Fang-fang Zhang Qing-miao Guo Hong-hang Hou Yao-qi Wang School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China Zhejiang Special Equipment Inspection and research Institute Hangzhou 310015 China General research Institute for Nonferrous Metals Beijing 100088 China Beijing Aeronautical Manufacturing Technology research Institute Beijing 100024 China

The hydrogen absorption kinetics of TA15 titanium alloy at 973-1123 K was studied using a tube-type hydrogen treatment furnace. The hydrogen absorption kinetic curves obtained were analyzed according to a series of mechanism equations to reveal the kinetic parameters and mechanism of the hydrogen absorption process. The results show that both the hydrogen absorption rate and the equilibrium hydrogen pressure increase and the time to reach equilibrium is shortened with increasing temperature. It is found that only the second hydrogen absorption period exists in the hydrogen absorption process of TA15 alloy between 973 and 1123 K, and the activation energy is 54.889 kJ/mol for hydrogen absorption. X-ray diffraction （XRD） and scanning electron microscopy （SEM） results demonstrate that δ hydride forms between 973 and 1123 K, and β phase decreases with the increase of temperature. Orthorhombic α＂ martensite is generated at 1073-1123 K, and their amount increases with increasing temperature.

关键词： titanium alloy kinetics activation energy microstructure

Design of cascading two stages of high gain harmonic generation scheme based on Shanghai deep ultraviolet free electron laser

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Chinese Physics C 2008年第3期32卷 236-242页

作者：邓海啸戴志敏 Shanghai Institute of Applied Physics CASShanghai 201800China Graduate University of Chinese Academy of SciencesBeijing 100049China Shanghai Institute of Applied Physics CASShanghai 201800China

Cascading stages of high gain harmonic generation free electron laser （FEL） seem to be a feasible way to generate short wavelength radiation. With help of the analytical estimates, we design a two-stage cascading scheme to achieve 131 nm DUV radiation on the basis of the Shanghai deep ultraviolet free electron laser test facility. Detailed studies on the FEL performance, the stability and the sensitivity of the output power to parameter variation have been achieved by GENESIS1.3, and design of the lattice structure is presented.

关键词： time jitter FEL HGHG

Relationship between heat treatment and corrosion behaviour of Mg-3.0%Nd-0.4%Zr magnesium alloy

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中国有色金属学会会刊：英文版 2007年第6期17卷 1152-1157页

作者：常建卫郭兴伍付彭怀彭立明丁文江 National Engineering research Center of Light Alloys Net Forming School of Materials Science and EngineeringShanghai Jiao Tong University

The corrosion behaviour of Mg-3.0Nd-0.4Zr (NK30) magnesium alloy was investigated in as-cast (F), solution treated (T4) and peak-aged (T6) conditions in 5% NaCl solution by immersion tests and electrochemical measurements. The results of immersion test show that NK30 alloy exhibits better corrosion resistance in F condition than it does in the other two conditions due to the more compact corrosion film formed on alloy in F condition. The potentiodynamic polarization curves show that the overpotential of cathodic hydrogen evolution reaction on NK30-F is much higher than that on NK30-T4 and NK30-T6. The corrosion potentials of NK30 increase in the following order: F

关键词： Mg-Nd-Zr合金腐蚀热处理电动位极化电气化学

Top slag refining for inclusion composition transform control in tire cord steel

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International Journal of Minerals,Metallurgy and Materials 2012年第6期19卷 490-498页

作者： Shu-hao Chen Min Jiang Xiao-fei He Xin-hua Wang state Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing Beijing 100083 China School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China

Controlling conditions for inclusion plasticization were calculated by FactSage, and the steel/slag reaction equilibration time was determined by pre-equilibrium experiments. Laboratory experiments with different top slags were carried out in 90 rain, and industrial tests were performed based on the results of calculation and laboratory experiments. Scanning electron microscopy （SEM） and energy-dispersive spectroscopy （EDS） were used to determine the morphology and composition of inclusions in tire cord steel. It is found that the shape of in- clusions can be controlled well, and the composition of inclusions varies in the industrial test as the following transformation route： MnO-A1EOa-SiO2→CaO-AIEOa-SiO2→MnO-A1203-SiO2. Inclusion plasticization can be achieved by controlling the binary basicity of top slag （CaO/SiO2 by mass） around 1.0 and the （A1203） content in top slag below 10wt%. Under these controlling conditions in the industrial test, almost all of inclusions in the wire rods achieve plastic deformation.

关键词： tire cords ladle metallurgy inclusions plasticity slags refining

Harmonic operation of high gain harmonic generation free electron laser

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Chinese Physics C 2008年第7期32卷 593-598页

In high gain harmonic generation （HGHG） free electron laser （FEL）, with the right choice of parameters of the modulator undulator, the dispersive section and the seed laser, one may make the spatial bunching of the electron beam density distribution correspond to one of the harmonic frequencies of the radiator radiation, instead of the fundamental frequency of the radiator radiation in conventional HGHG, thus the radiator undulator is in harmonic operation （HO） mode. In this paper, we investigate HO of HGHG FEL. Theoretical analyses with universal method are derived and numerical simulations in ultraviolet and deep ultraviolet spectral regions are given. It shows that the power of the 3rd harmonic radiation in the HO of HGHG may be as high as 18.5% of the fundamental power level. Thus HO of HGHG FEL may obtain short wavelength by using lower beam energy.

关键词： harmonic operation HGHG FEL

Incubation and development of corrosion in microstructures of low alloy steels under a thin liquid film of NaCl aqueous solution

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International Journal of Minerals,Metallurgy and Materials 2010年第6期17卷 748-755页

作者： Wen-hua Zhang Shan-wu Yang Jia Guo Zhi-yong Liu Xin-lai He School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

Electrochemical measurement, optical microscopy, and scanning electron microscopy were employed to investigate the corrosion behavior of some low alloy steels. The steels were held under a thin liquid film of 0.5wt% NaCl aqueous solution. It is found that the steels with the same chemical composition but different micmstructures exhibit obviously different corrosion behaviors. However, the corrosion behavior of the steels with different compositions but the same microstructnres may be similar in the present investigation. The corrosion rate of bainite is slower than that of ferrite and pearlite. The corrosion products of bainite are uniform and fine. The size of carbon-rich phases produces a great impact on the corrosion of the steels, whether in the initial stage or in the long tenn. It is easy to induce large pitting for carbon-rich phases with large size, which damages the compactness of the rust layer.

关键词： alloy steel microstructure atmospheric corrosion liquid films scanning electron microscope

Effects of heat treatments on microstructure and mechanical properties of Mg-15Gd-5Y-0.5Zr alloy

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Journal of Rare Earths 2008年第2期26卷 298-302页

作者：高岩王渠东顾金海赵阳童炎 Junya Kaneda National Engineer research Center of Light Alloys Net Forming Shanghai Jiao Tong University Hitachi (china) research & Develop- ment Corp. Shanghai Research Institute Hitachi Ltd. Materials Research Laboratory 1-1 Omika-cho 7-chome Hitachi-shi Ibaraki-ken 319-1292 Japan

Microstructure and mechanical properties of Mg-15wt.%Gd-5 wt.%Y-0.5wt.% Zr alloy were investigated in a series of conditions. The eutectic was dissolved into the matrix and there was no evident grain growth after solntionized at 525 ℃ for 12 h. The evolution of the phase constituents from as-cast to cast-T4 was as follows： α-Mg solid solution＋Mg5（Gd,Y） entectic compound→α-Mg solid solution＋ spheroidized Mg5（Gd, Y） phase→α-Mg supersaturated solid solution＋cuboid-shaped compound （Mg2Y3Gd2）. And the precipitation sequences of Mg-15Gd-5Y-0.5Zr alloy were observed, according to the hardness response to isothermal ageing at 225-300 ℃ for 0-128 h.

关键词： Mg-Gd-Y-Zr alloys solution heat treatment microstructure mechanical properties rare earths

Effect of Co-polyester antistatic agent modified by carbon nanotubes on the properties of polypropylene fibers

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Journal of University of Science and Technology Beijing 2007年第6期14卷 573-579页

作者： Chensha Li Binsong Wang Weizhe Lu Dazhi Wang Zhi Li Zechao Di Ji Liang Department of Mechanical Engineering Tsinghua University Beijing 100084 China School of Chemistry and Materials Science Heilongjiang University Harbin 150080 China

Antistatic polymer fibers were investigated by using carbon nanotubes （CNTs） to enhance the antistatic ability of inner antistatic agents based on the mechanism of attracting moisture by polar radical groups. It is indicated that the antistatic ability of the fibers filled with composite antistatic agents that contain CNTs and organic antistatic agents was superior to that of the fibers filled either with pure organic antistatic agents or pure CNTs. The antistatic ability of the composite antistatic agent fabricated by an in situ process was superior to that of the composite antistatic agent fabricated by direct dispersing CNTs in the antistatic agent carrier. Moreover, the heat-treated CNTs could further enhance the antistatic effect compared with the initial CNTs. The antistatic effect is significantly influenced by the content of CNTs in the composite antistatic agent.

关键词： carbon nanotube polypropylene fiber antistatic agent in situ process

Preliminary Shielding Analysis for HCCB TBM Transport

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Plasma Science and Technology 2015年第9期17卷 781-786页

作者：缪鹏赵奉超曹启祥张国书冯开明 School of Nuclear Science and Technology University of Science and Technology of China Southwestern Institute of Physics

A preliminary shielding analysis on the transport of the Chinese helium cooled ceramic breeder test blanket module（HCCB TBM） from France back to china after being irradiated in ITER is presented in this *** was placed on irradiation safety during *** dose rate calculated by MCNP/4C for the conceptual package design satisfies the relevant dose limits from IAEA that the dose rate 3 m away from the surface of the package containing low specific activity III materials should be less than 10 mSv/*** change with location and the time evolution of dose rates after shutdown have also been *** will be helpful for devising the detailed transport plan of HCCB TBM back to china in the near future.

关键词： HCCB TBM shielding MCNP transport