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Rare metals 2024年第4期43卷 1786-1792页

作者： Yuan-Feng Xie Xing-Cheng Xie Zhong-Wu Li Rui-Jun Cao Zhong-Kun Lin Qing Li Chen-Guang Lin Powder Metallurgy and Special Materials research Department General Research Institute for Nonferrous Metals

The effects of cryogenic treatment（CT） and tempering-cryogenic treatment（TCT） on the microstructure and properties of coarse-grained WC-10Co cemented carbides with different carbon contents were researched.The binder phase,WC mean grain sizes,W solubility in the binder,relative magnetic s aturation,densities,hardness,wear resistance and second phase precipitation of cemented carbides with different heat treatments were discussed.The results show that there are significant changes of microstructure and properties in the samples with CT and TCT,especially due to the precipitation of metastable nanoparticles WxCoyCzin the binder during the heat treatments of CT and TCT.With the simultaneous combination of microstructure and nanoparticle-reinforced binder,a dramatically improved combination of hardness and wear resistance of the samples after TCT has been achieved.

关键词： Cryogenic treatment Tempering Coarse-grained cemented carbide Carbon content Nanoparticle-reinforced binder

Effect of thermal shield and gas flow on thermal elastic stresses in 300mm silicon crystal

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Rare metals 2006年第Z2期25卷 45-50页

作者： GAO Yu XIAO Qinghua ZHOU Qigang DAI Xiaolin TU Hailing general research institute for nonferrous metals Beijing 100088 China General Research Institute for Nonferrous Metals Beijing 100088 China General Research Institute for Nonferrous Metals Beijing 100088 China General Research Institute for Nonferrous Metals Beijing 100088 China General Research Institute for Nonferrous Metals Beijing 100088 China

The thermal elastic stresses induced in 300 mm Si crystal may be great troubles because it can incur the generation of dislocations and undesirable excessive residual stresses. A special thermal modeling tool, CrysVUn, was used for numerical analysis of thermal elastic stresses and stress distribution of 300 mm Si crystal under the consideration of different thermal shields and gas flow conditions. The adopted governing partial equations for stress calculation are Cauchy′s first and second laws of motion. It is demonstrated that the presence and shape of thermal shield, the gas pressure and velocity can strongly affect von Mises stress distribution in Si crystal. With steep-wall shield, however, the maximal stress and ratio of high stress area are relatively low. With slope-wall shield or without shield, both maximal stress and ratio of high stress area are increased in evidence. Whether thermal shields are used or not, the increase of gas flow velocity could raise the stress level. In contrast, the increase of gas pressure cannot result in so significant effect. The influence of thermal shield and gas flow should be attributed to the modification of heat conduction and heat radiation by them.

关键词： thermal elastic stress simulation 300 mm Si single crystal

Preparation and characterization of Rb-doped TiO_(2) powders for photocatalytic applications

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Rare metals 2024年第2期43卷 555-561页

作者： Lu Jia Li-Mei Yang Wei Wang Song-Tao Huang Zheng Xu National Engineering Laboratory of Biohydrometallurgy General Research Institute for Nonferrous MetalsBeijing100088China

TiO_(2)nanoparticles doped with different concentrations of Rb were prepared by sol–gel method.The crystal structures of samples were characterized by X-ray diffraction(XRD)and transmission electron microscopy(TEM).It was confirmed by the Rietveld refinement method that the as-prepared samples crystallize in anatase phase and Rb doping induces expansion and distortion of the crystal lattice.Compared with the pure TiO_(2),the Rb-doped nanoparticles have smaller crystal size and better dispersibility.Degradation rate of methylene blue was used to evaluate the photocatalytic activity of Rb–TiO_(2).It indicated that doping Rb into TiO_(2)can effectively improve the photocatalytic activity of TiO_(2)and the mechanisms were discussed in detail.When using the sample doped with 0.20%Rb,methylene blue degraded with the fastest rate(97%within 60 min).

关键词： Rb doping TiO_(2) Photocatalysis Sol-gel

Dielectric and energy storage properties of PbO–SrO–Nb_(2)O_(5)–Na_(2)O–Si thin films by annealing

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Rare metals 2024年第1期43卷 351-355页

作者： Fei-Hu Tan Qing-Meng Zhang Feng Wei Hong-Bin Zhao Xiao Zhang Jun Du State Key Laboratory of Advanced Materials for Smart Sensing General Research Institute for Nonferrous MetalsBeijing 100088China Advanced Electronic Materials institute General Research Institute for Nonferrous MetalsBeijing 100088China

Dielectric and energy storage properties of PbOSrO-Na_(2)O-Nb_(2)O_(5)-SiO_(2)(PSNNS) thin films with annealing temperature from 700 to 850 ℃ were investigated by measuring their capacitance-electric filed curve and hysteresis loops.The results show that the highest dielectric constant and energy density are 81.2 and 17.0 J·cm^(-3),respectively,which is obtained in the sample with annealing temperature of 800 ℃.Annealed from 700 to800 ℃,the dielectric constant and energy storage performance of PSNNS films are continuously improved.However,with annealing temperature up to 850 ℃,their dielectric constant decreases,which might be related with the removal of interfacial defects as a function of annealing temperature.Defect is one of the causes of space charge phenomenon,resulting in the increase in dielectric constant.Moreover,the micro structure analysis by X-ray diffraction(XRD) and transmission electron microscope(TEM) indicates that the change of crystallization phase and interfacial polarization takes responsibility to the results.

关键词： Thin film Pulse laser deposition Annealing temperature Energy storage density

Microstructure evolution of Al-Zn-Mg-Cu-Zr alloy during hot deformation

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Rare metals 2010年第4期29卷 426-432页

作者： YAN Liangming,SHEN Jian,LI Zhoubing,LI Junpeng,and YAN Xiaodong general research institute for nonferrous metals,Beijing 100088,China general research institute for nonferrous metals Beijing China

Compression tests of the Al-Zn-Mg-Cu-Zr（7055） alloy were performed at various strains and temperatures from 300 to 450℃ under a con- stant strain rate between 10^-2 s^-1and 1 s^-1. Microstructures during hot deformation were studied by transmission electron microscopy （TEM）. Dislocation density, dislocation cells and subgrains of the deformed samples were investigated in detail and compared to make a better understanding of the microstructure evolution. The results showed that stress-strain curves under the experimental conditions belonged to the type of dynamic recovery. When the alloy deformed at various strains and 300℃, the microstructure underwent a process of disordered dislocations to cell structure, subgrain structure and subgrain coarsening. With the temperature increasing, subgrains grew and dislocation density in the interior decreased at a strain rate of 1 s^-1. At the temperature of 350℃, the average diameter of subgrains decreased, sub-boundaries broadened and dislocation density in the interior decreased when the strain rate was increased. The deformed samples of 7055 alloy had smaller subgrains than that of 7005 alloy at the same compression condition because of high alloy content.

关键词： aluminum alloy microstructure evolution dynamic recovery subgrain

A high-performance lithium anode based on N-doped composite graphene

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Rare metals 2024年第3期43卷 1030-1036页

作者： Can Jiao Hao-Bo Sun Li Zhang Shang-Qian Zhao Guo-Yao Pang Chun-Rong Zhao Shi-Gang Lu general research institute for nonferrous metals Beijing100088China China Automotive Battery research institute Co.Ltd Beijing101407China

Lithium(Li)metal is the most promising electrode for next-gene ration rechargeable batteries.In order to push the commercialization of the lithium metal batteries,a kind of nitrogen(N)-doped composite graphene(NCG)adopted as the Li plating host was prepared to regulate Li metal nucleation and suppress dendrite growth.Furthermore,a new kind of sandwich-type composite lithium metal(STCL)electrode was developed to improve its application.The STCL electrode can be used as convenient as a piece of Li foil but no dendrite growth.In a symmetric battery,the STCL electrode cycled for more than 4500 h with the overpotential of less than 40 mV.And due to the creative design,the STCL promises the Li-S battery with a prolonged cycling lifespan.

关键词： Lithium metal anode Lithiophilic N-doped composite graphene Sandwich-type composite lithium metal electrode

Enhancement of Ti-Cr-V BCC alloys on the dehydrogenation kinetics of Li-Mg-N-H hydrogen storage materials

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Rare metals 2010年第6期29卷 621-624页

作者： WANG Jingchuan,LI Zhinian,LI Hualing,MI Jing,Lü Fang,WANG Shumao,LIU Xiaopeng,and JIANG Lijun general research institute for nonferrous metals,Beijing 100088,China general research institute for nonferrous metals Beijing China

The hydrogen storage properties of a Li-Mg-N-H material doped by a 4 mol.% Ti3Cr3V4 body centre cubic（BCC） alloy hydride and prepared with a ball-milling method were investigated by X-ray diffraction,scanning electron microscopy,transmission electron microscopy and Sievert＇s technology test.The results show that the Ti3Cr3V4 BCC alloy hydride/Li-Mg-N-H composite has good reversible hydrogen storage properties.The dehydrogenation kinetics of the Li-Mg-N-H system can be greatly improved by doping the Ti3Cr3V4 BCC alloy hydride.The composite desorbed 4.1 wt.% hydrogen in the first 60 min at 473 K under 0.1 MPa pressure,but when without the BCC alloy addition,only 3.0 wt.% hydrogen was desorbed under the same dehydrogenation condition.It can be deduced that the Ti3Cr3V4 BCC alloy uniformly distributed in the Li-Mg-N-H substrate could decrease the activating energy of hydrogen molecules to H atoms and increase H diffusion paths in the composite,enhancing the dehydrogenation kinetics of the Li-Mg-N-H system.

关键词： hydrogen storage alloys hydrogen storage hydrides dehydrogenation

Thermal Performance Analysis of LED with Multichips

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Journal of Wuhan University of Technology(Materials Science) 2011年第6期26卷 1089-1092页

作者：韩媛媛 general research institute for nonferrous metals

The package and system level temperature and thermal stress distributions of 10 W light emitting diode （LED） with 4 chips and 100 W LED with 100 chips were investigated using finite element analysis. The chips were arranged on a Si sheet which is soldered on the copper/diamond composite slug with very high conductivity. The experimental results show that the maximal temperature appears in the chips of both two high power LEDs packages. Compared with the 10 W LEDs package with 4 chips array, the heat issue caused by stacking and coupling of the heat in 100 W LEDs package with 100 chips array is more serious. The chip temperature in the center of the array is much higher, and it decreases with the distance between the chip and the center of LEDs increases. Great thermal stress lies between the chips and the solder, which will reduce the reliability of the package.

关键词： high power LED package copper/diamond composite finite element analysis junctiontemperature thermal stress

Effect of thermomechanical treatment on microstructure and properties of Cu-Cr-Zr-Ag alloy

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Rare metals 2011年第6期30卷 650-656页

作者： XIE Haofeng MI Xujun HUANG Guojie GAO Baodong YIN Xiangqian LI Yanfeng State Key Laboratory of nonferrous metals and Processes General Research Institute for Nonferrous Metals Beijing 100088 China

The effects of thermomechanical treatment on the properties and microstructure of Cu-Cr-Zr alloy and Cu-Cr-Zr-Ag alloy were investigated. Ag addition improves the mechanical properties of the alloy through solid solution strengthening and brings a little effect on the electrical conductivity of the alloy. A new Cu-Cr-Zr-Ag alloy was developed, which has an excellent combination of the tensile strength, elongation, and electrical conductivity reaching 476.09 MPa, 15.43% and 88.68% IACS respectively when subjected to the optimum thermomechanical treatment, i.e., solution-treating at 920℃ for 1 h, cold drawing to 96% deformation, followed by aging at 400℃ for 3 h. TEM analysis revealed two kinds of finely dispersed precipitates of Cr and CuaZr. It is very important to use the mechanisms of solid solution strengthening, work hardening effect as well as precipitate pinning effect of dislocations to improve tensile strength of the alloy without adversely affecting its electrical conductivity.

关键词： Cu-Cr-Zr-Ag alloy thermomechanical treatment microstructure tensile strength electrical conductivity

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) general research institute for nonferrous metals Beijing 100088 China

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