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Diffusion mechanism of dezincification in double phase brass exposed to seawater

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中国有色金属学会会刊：英文版 1999年第3期9卷 572-577页

作者： Liu Zengcai(刘增才) Lin Leyun(林乐耘) Liu Shaofeng(刘少峰) Zhao Yuehong(赵月红) gen res inst nonferrous met Beijing 100088 Peoples R China

Zinc diffusion kinetics of double phase brass as they were corroded in seawater was investigated by means of metallography microscope and mathematics regression analysis. The results showed that, the dezincification corrosion of β phase continuous HMn58 2 brass is characterized by β phase volume diffusion, while that of α phase continuous HSn62 1 brass is controlled by α phase grain boundary diffusion. Apparent diffusion coefficients of zinc in both types alloys were calculated out by founding diffusion equation and boundary conditions. It was found that the value of theoretical calculation is close to that of experimentally measured, and it confirmed that Sn element inhibits dezincification of brass. The relativity between the dezincification depth and corrosion rate of different double phase brasses immersed in seawater was revealed. : Zinc diffusion kinetics of double phase brass as they were corroded in seawater was investigated by means of metallography microscope and mathematics regression analysis. The results showed that, the dezincification corrosion of β phase continuous HMn58 2 brass is characterized by β phase volume diffusion, while that of α phase continuous HSn62 1 brass is controlled by α phase grain boundary diffusion. Apparent diffusion coefficients of zinc in both types alloys were calculated out by founding diffusion equation and boundary conditions. It was found that the value of theoretical calculation is close to that of experimentally measured, and it confirmed that Sn element inhibits dezincification of brass. The relativity between the dezincification depth and corrosion rate of different double phase brasses immersed in seawater was revealed.

关键词： seawater corrosion brass dezincification boundary diffusion

research and Development of Rare Earth Advanced Materials in China

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Journal of Rare Earths 1996年第3期14卷 223-230页

作者：王淀佐万群杨遇春 gen res inst nonferrous met BEIJING 100088PEOPLES R CHINA

China is rich in resources of rare earths(res). Based on tremendous work, China has made great achievements in research and development of res since 1980s, and the production of RE has won the leading position in the world. The application of RE elements in advanced materials have progressed significantly during the past years. The wide range of rare earth application in China has been reviewed and discussed in this paper, including the development of advanced RE materials (RE-Al alloys, rare earth nonferrous metal alloys, rare earth luminescent materials, rare earth hydrogen storage materials, rare earth permanent magnet and rare earth compounds used in agriculture, i.e., rare earth micronutrient fertilizer etc.) End the research of new RE materials (high T-c rare earth superconductor, rare earth electronic and photonic materials, rare earth ceramics and rare earth precious metal alloys). Finally, the further development works to be required are as follow: (1) to enhance the applied fundamental research, study the intrinsic properties of rare earth elements and develop less well known uses; (2) to undertake the applied research of median and heavy rare earth and find a way out of the unbalance of RE resources in the various applications; (3) to strengthen the applied research of RE element's in energy field, solving the energy-related, energy-saved and environmental problems.

关键词： RE-Al alloys rare earth nonferrous metal alloys rare earth compounds used in agriculture high T-c rare earth superconductors

MICROSTRUCTURE　OF　INTERFACE　BETWEEN　HVOF　SPRAYED　WC－Co　COATING　AND　SPRING　STEEL　SUBSTRATE

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中国有色金属学会会刊：英文版 1996年第4期6卷 76-81页

作者： Shao Beiling Liu Ansheng Wang Xiaohua Li Yonghong Zou Linying Wang Jing Zhang Jianguo Shi Changyong Zhou Yiru(general research institute For nonferrous metals,Beijing 100088) gen res inst nonferrous met BEIJING 100088PEOPLES R CHINA

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关键词： high velocity oxygen-fuel flame spraying microstructure interface

Applications of Secondary Electron Composition Contrast Imaging method in Microstructure Studies on Heterojunction Semiconductor Devices and Multilayer Materials

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Rare metals 1999年第2期18卷 2-8页

作者：刘安生邵贝羚安生王敬刘铮 gen res inst nonferrous met Beijing 100088 Peoples R China

The principle, imaging condition and experimental method for obtaining high resolution composition contrast in secondary electron image were described. A new technique of specimen preparation for secondary electron composition contrast observation was introduced and discussed. By using multilayer P+Si1-xGex/pSi heterojunction internal photoemission infrared detector as an example, the applications of secondary electron composition contrast imaging in microstructure studies on heterojunction semiconducting materials and devices were stated. The characteristics of the image were compared with the ordinary transmission electron diffraction contrast image. The prospects of applications of the imaging method in heterojunction semiconductor devices and multilayer materials are also discussed.

关键词： Secondary electron composition contrast image Heterojunction semiconducting devices Multilayer materials Electron microscopy Microstructure

Present Situation of Purification Technologies for Automotive Exhaust in China

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Rare metals 2000年第1期19卷 46-52页

作者：崔梅生李东培 gen res inst nonferrous met Beijing 100088 Peoples R China

It is presented that eliminating and controlling the current automotive exhaust emission should be important and urgent in China, and the Chinese state emission standards have been getting stricter and stricter. Also the present purification technologies for automotive exhaust are elucidated. It is indicated that the development and the commercialization of Rare Earth based on three way catalytic converters is pretty necessary and urgent to address the current harsh automotive exhaust emission problems in China. In addition, the future automotive exhaust purification technologies are prospected.

关键词： Automotive exhaust Emission control Purification technologies

Fabrication　and　Maglev　Properties　of　Large　Bulk　Melt－Texture－Growth　YBCO　Superconductor

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Journal of Rare Earths 1996年第4期14卷 279-285页

作者：任洪涛肖玲焦玉磊王永兰 gen res inst nonferrous met BEIJING 100088PEOPLES R CHINA

The fabrication of large bulk high temperature superconducting YBCO samples was accomplished by melt-texture-growth(MTG) process with a seeding *** microstructure of the samples was observed by a polarization *** observation shows that the samples have controlled orientation and large *** magnetic repulsion measurements as a function of distance were carried *** maximum repulsion between the YBCO sample(29 mm in diameter and 10 mm thick) and a Nd-Fe-B permanent magnet with 0.5T surface magnetic field was 4.8 N/cm2 at *** magnetic levitation on the samples exhibits anisotropic behaviour.

关键词： MTG YBCO Superconductor Levitation force Seeding technique

TEM study on Si_(0.65) Ge_(0.35) /p Si HIP infrared detector

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中国有色金属学会会刊：英文版 1999年第3期9卷 481-486页

作者： Liu Ansheng(刘安生), Shao Beiling(邵贝羚), Liu Zheng(刘峥), Wang Jing(王敬) general research institute for nonferrous metals, Beijing 100088, P.R.China gen res inst nonferrous met Beijing 100088 Peoples R China

Microstructure of P + Si 0.65 Ge 0.35 /p Si HIP infrared detector has been studied by using localization cross section transmission electron microscopy. The photosensitive region of the detector consists of 6 P + Si 0.65 Ge 0.35 layers and 5 UD Si layers, which are flat and have thickness of 6 nm and 32 nm, respectively. A stress field exists on the interface between Si 0.65 Ge 0.35 and UD Si layers, but no any crystal defect has been found in this region, except the edges of this region. Both Si 0.65 Ge 0.35 and UD Si layers on amorphous SiO 2 layer consist of polycrystals and are in wave. There is defect area in the edges of photosensitive region. The area appears in a shape of inverse triangle and the maximum width is less than 120 nm. The crystal defects are stacking faults and microtwins.

关键词： infrared detector heterojunction semiconductor device microstructure of semiconductor device transmission electron microscopy

Heat Treatment, Microstructure and Mechanical Properties of the Squeezing Cast Al-7.8Zn-2.0Mg-1.6Cu-0.15Zr-0.18Sc Alloy

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稀有金属材料与工程 2011年第S3期40卷 82-85页

作者： Tu Qiang, Yang Fubao, Xu Jun, Zhang Zhifeng, Li Daquan nonferrous metals Processing Division , general research institute for Non-ferrous metals, Beijing 100088, China gen res inst nonferrous met Nonferrous Met Proc Div Beijing 100088 Peoples R China

The microstructure of squeezing cast Al-7.8Zn-2.0Mg-1.6Cu-0.15Zr-0.18Sc alloy and those after industrial homogenization treatment and multi-stage solution treatments, were studied by differential scanning calorimetry (DSC), optical microscopy (OM), transmission electron microscope (TEM), scanning electron microscopy with energy dispersive X-ray spectroscopy (TEM-EDX). The results shows that, by complex adding the micro-alloying elements Mn, Sc, Zr, etc ,the microstructure of squeezing casting ingot are fine, uniform, equiaxed, and with the average sizes of 40 μm. The melting point of the non-equilibrium eutectic is 468 ℃ for the casting ingot. After industrial homogenization treatment at 450 ℃ for 24 h, the tensile strength of as-cast alloy is 340-350 MPa and the elongation is 3.5%-4.5%. The multi-stage solution treatment at 465 ℃, 48 h +475 ℃, 8 h +485 ℃, 2 h results in the disappearance of the non-equilibrium eutectics at grain boundary, though some phases containing Fe and Cu can not dissolve completely. After 120 ℃, 24 h aging treatment, the tensile strength is nearly 600 MPa, and the elongation improve to more than 10%.

关键词： squeezing casting homogenization treatment multi-stage solution mechanical properties

Development of embedded-atom potentials and prediction of properties for binary Ti-V

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中国有色金属学会会刊：英文版 2000年第5期10卷 635-638页

作者：商顺利刘玉芹白克武沈剑韵王希哲 gen res inst nonferrous met Beijing 100088 Peoples R China

The embedded atom potentials for binary Ti V were developed and used to predict the mechanical properties of binary Ti V solid solutions with hcp and bcc structures including lattice parameters, elastic constants and fracture toughness for Mode Ⅰ fracture under plane strain. The calculation results show that with the increment of V content, the lattice parameters and elastic constants decrease but the fracture toughness increases for hcp solid solutions, the lattice parameters decrease but the elastic constants and fracture toughness increase for bcc solid solutions. The calculation results agree well with the available experiment values. [

关键词： embedded atom potentials Ti V system lattice parameters elastic constants fracture toughness