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Effects of Zr and Y on the Mechanical Properties and the Microstructure of Ti-Al-Sn-Nb-Mo-Si Alloy

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Rare metals 1990年第1期10卷 39-45页

作者： Qin, Kuiqing Wang, Lida Tang, Shisheng General Research Inst for Non-ferrous metals China

In the present paper the effects of additions of Zr and Y on the microstructure and mechanical properties for Ti-(6.0 approximately 6.5)Al-(2.0 approximately 3.0)Sn-(1.5 approximately 6.0)Zr-(0.8 approximately 1.0)Mo-1.0Nb-0.25Si alloys are reported. The experimental results shows that: with increasing of Zr content, tensile strength and creep resistance of the alloys increase, and reduction in area and thermal stability of the alloys decrease. Decrease in thermal stability of the alloys mainly caused by surface thermal unstability. After heat treatment Y addition can make grain size of the alloys refine. The reduction in area and thermal stability of the alloys with Y addition are improved, and tensile strength slightly decreases and creep resistance is essentially the same as the alloy without Y addition. These phenomena are explained in brief.

关键词： metals Testing Fracture Titanium and Alloys Composition Effects Titanium Metallography Microstructures Yttrium and Alloys Effects Zirconium and Alloys Effects

Effects of Different Substrates on Microstructures and Mechanical Properties of a Bulk Nanocrystalline Structure Pure Iron Prepared by Aluminothermic Reaction Casting

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Journal of Iron and Steel Research International 2015年第4期22卷 324-329页

作者： Xiao-juan ZHEN Pei-qing LA Cui-ling LI Su-lei HU State Key laboratory of Advanced Processing and Recycling of non-ferrous metals Lanzhou University of Technology

A simple method was developed to produce the nanocrystalline pure iron by aluminothermic reaction cast- ing. The mierostructure of the iron was investigated by optical microseope （OM）, transmission electron microscope （TEM）, electron probe micro-analyzer （EPMA）, scanning electron microscope （SEM） and X-ray diffraction （XRD）. The mechanical performances of nanoerystalline pure iron were tested. It is found that the pure iron consists of nanoerystalline ferrite. For different substrates of eopper and glass, the average grain size of the ferrite was 38 and 35 nm, respectively, which is larger on copper substrate than that on glass. The hardness, compressive strength, tensile strength, and total elongation are 167 and 137 HB, 400 and 500 MPa, 243 and 185 MPa, 16% and 10% on copper substrate and glass suhstrate, respectively. The hardness, tensile strength and total elongation are all larger on copper substrate than those on glass substrate, while the eompressive strength is lower. The large supercooling in the product solidification provides the condition for high nucleation rate and thus leads to nano-grained austenite and final nano-grained ferrite transformed from those small austenite grains.

关键词： nanocrystalline aluminothermic reaction casting pure iron substrate microstructure mechanical property

Physical and Electrochemical Properties of Doped LiFePO4 as Cathode Material for Lithium-Ion Batteries

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Journal of Rare Earths 2004年第Z2期22卷 123-125页

作者： Yao Yongxun Duan Zhenzhong Li Yuenan Gu Hongwei Hua Zhiqiang Luan Wenzhou Wang Yuan Research Center of Superconducting Materials General Research Institute for Non-Ferrous MetalsBeijing 100088China Research Center of Superconducting MaterialsGeneral Research Institute for Non-Ferrous MetalsBeijing 100088China Research Center of Superconducting MaterialsGeneral Research Institute for Non-Ferrous MetalsBeijing 100088China Research Center of Superconducting MaterialsGeneral Research Institute for Non-Ferrous MetalsBeijing 100088China Research Center of Superconducting MaterialsGeneral Research Institute for Non-Ferrous MetalsBeijing 100088China Research Center of Superconducting MaterialsGeneral Research Institute for Non-Ferrous MetalsBeijing 100088China Research Center of Superconducting MaterialsGeneral Research Institute for Non-Ferrous MetalsBeijing 100088China

LiFePO4 cathode material was synthesized by a solid-state reaction using doping several elements (Nb5 + ,Zr4 + ). The starting materials were mixed with a high-efficient sander and treated thermally under flowing N2. The samples were characterized by X-ray diffraction (XRD), field-emission gun electron microscopy (FEG), and their electrochemical performance was investigated in the term of cycling behavior. Room temperature discharge capacity about 140.6 mA·h·g-1 was obtained at C/5 rate.

关键词： Lithium-ion batteries LiFePO4 cathode material discharge capacity

Annular electromagnetic stirring——a new method for the production of semi-solid A357 aluminum alloy slurry

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Acta Metallurgica Sinica(English Letters) 2009年第6期22卷 408-414页

作者： Guanglei ZHU Jun XU Zhifeng ZHANG Yuelong BAI Likai SHI National Engineering ＆ Technology Research Center for non-ferrous Metal Matrix Composites General Research Institute for Non-ferrous Metals Beijing 100088 China

A new method for producing semisolid slurry, annular electromagnetic stirring （AEMS）, to refine and spheroidize grains was exploited. Experimental work was undertaken to investigate the effects of cooling rate, stirring power and stirring time on the solidification behavior of A357 alloy using A-EMS. It was found that increasing the cooling rate and stirring power gave rise to substantial grain refinement, which could be attributed to the increase of effective nucleation rate caused by the extremely uniform temperature and composition fields in the bulk liquid during the initial stage of solidification. Results showed that a fully grain refined spherical structure could be obtained using proper processing conditions within 10 s.

关键词： Semisolid Annular electromagnetic stirring A357

Superconductivity and Structure of BiSrCaEuCuO Compound

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Rare metals 1989年第2期9卷 65-66页

作者： Wang, Ruikun He, Qing Yu, Dingan General Research Inst for Non-ferrous Metals China

Since the discovery of superconductivity of the BiSrCuO system at 20K, the work of synthesizing high Tc superconductors without rare-earths by adding some elements other than rare-earths in the BiSrCuO system has made a lot of progress. Recently, N. Fukushima et al. have synthesized Bi4Sr4RE2Cu4O16+δ (RE = Nd, Eu or Y) by substituting RE for Ca in the Bi4Sr4Ca2Cu4O16+δ superconductor and revealed that it has a crystal structure identical with this superconductor, but it is an insulator. In this paper, the authors report the superconductivity and structure of the BiSrCaEuCuO compound synthesized by adding 5 at% of rare-earth Eu in the BiSrCaCuO system.

关键词： Ceramic Materials Copper Compounds Europium Compounds Oxides Phase Transitions Superconductivity Temperature Effects

Growth and Properties of In-Doped Semi-insulating GaAs Crystals

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Rare metals 1989年第3期9卷 57-60页

作者： Ma, Bichun Wang, Yonghong Ma, Sansheng General Research Inst for Non-ferrous Metals China

Semi-insulating (SI) GaAs doped with indium has been grown and characterized. The relationship between the dislocation density and dopant concentration has been discussed. Study of the uniformity of electric properties of In-doped SI-GaAs, which has been annealed at 950°C for 6h under arsenic pressure, associates with decreases of point defects and arsenic vacancies.

关键词： Crystals Dislocations Indium Compounds Effects Semiconductor Materials Doping

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FEATURES

Rare metals 1989年第1期9卷 70-74页

作者： Anon General Research Inst for Non-ferrous Metals China

The General Research Institute for non-ferrous metals, Beijing, founded in 1952, is the largest institute engaged in the research and development of non-ferrous metals in China. Research is carried out in 21 laboratories. GRINM's research projects are principally related to the development of new materials. It is a base for the study and development of semiconductor materials in China. The Institute also carries out research and development of energy materials, structural metals and ceramics, and forming processes.

关键词： nonferrous metals Peoples Republic of China

Ytterbium Hydroxide and Erbium Hydroxide Coating of Spherical Nickel Hydroxide Positive Materials for Ni-MH Batteries at High-Temperature

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Journal of Rare Earths 2007年第S1期25卷 400-405页

作者：张文广蒋文全于丽敏傅钟臻夏雯郭荣贵陈飞彪李涛 General Research Institute for non-ferrous metals

For the purpose of the important high-temperature charge-discharge performances of spherical Ni(OH)2 used as positive materials for Ni-MH batteries, Yb(OH)3 and Er(OH)3 were used for surface coating of spherical Ni(OH)2 to improve its high-temperature properties. The coated spherical Ni(OH)2 was prepared by chemically coprecipitation of Yb(OH)3 and Er(OH)3 on the surface of spherical Ni(OH)2, respectively. The products were characterized by X-ray diffraction(XRD) and scanning electron microscope(SEM). The X-ray analysis showed that the structure of the coated spherical Ni(OH)2 was still β-Ni(OH)2. The SEM studies revealed that coating layer uniformly covered the surface of spherical Ni(OH)2. The electrochemical studies revealed that coating of Yb(OH)3 and Er(OH)3 exhibited superior performance such as high discharge capacity, excellent charge-discharge properties at high-discharge rate at 65 ℃. The charge acceptance was above 85% at 1C rate at 65 ℃. The discharge capacity approached to 230 mAh·g-1 at 0.2C rate, which even reached 270 mAh·g-1 at 1C rate for both Yb(OH)3 and Er(OH)3 coated spherical Ni(OH)2, where the discharge capacity for uncoated one was only 250 mAh·g-1 . The cyclic voltammetry analysis of spherical Ni(OH)2 showed that the oxidation potential, the oxygen evolution potential, and the difference between them increased after the coating both at 25 and 65 ℃. It was shown that the Yb(OH)3 and Er(OH)3 coating is an effective way to improve the high-temperature performance of spherical Ni(OH)2 for Ni-MH batteries. The studies showed that Yb(OH)3 and Er(OH)3 coated spherical Ni(OH)2 would be a promising material of Ni-MH batteries for hybrid vehicle (HEVs), electric vehicles(EVs) and rapid charge devices due to excellent high rate charge-discharge performance.

关键词： Yb(OH)_3 Er(OH)_3 spherical Ni(OH)_2 coating high-temperature high-discharge rate

Effect of Oxygen and Hydrogen on Electron Irradiated Defects of Si Single Crystal

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Rare metals 1989年第1期9卷 28-31页

作者： Gao, Yuzun Takahashi, H. Sato, Y. Takeyama, T. Nagasaki, R. General Research Inst for Non-ferrous Metals China

CZ-Si and FZ-Si single crystal specimens were irradiated by electron beam with energy of 1MV in HVEM at temperatures between 298K and 773K. It was found that irradiated defects were easier to produce in Si single crystal containing oxygen than in Si containing hydrogen. The defects had a larger density and shorter incubation time in Si containing oxygen. The bar-like defects, stacking faults and loops were along 110 direction. Bar-like defects and stacking faults were Burgers vector 116 direction type and the stacking faults were on the (113) plane.

关键词： Semiconductor Materials Defects