ZHANG Yun
,
LIU Yulin
,
ZHAO Hong' en
,
HU Zhuangqi
,
Institute of Metal Research
,
Academia Sinica
,
Shenyang
,
ChinaZHU Zhiyong
,
WANG Zhengfu
,
Institute of Corrosion and Protection of Metals
,
Academia Sinica
,
Shenyang
,
China ZHANG Yun
,
Associate Professor
,
Institute of Metal Research
,
Academia Sinica
,
Shenyang 110015
,
China
金属学报(英文版)
The A1-2.79Li-1.3Cu-0.7Mg-0.12Zr(8090) alloy has excellent resistance to intergranular and exfoliation corrosion as naturally aged, worst as peak aged and rather better as underaged than as overaged. The corrosion behaviour of the alloy is closely dependent on its microstructure. Under the peak aging condition, the coarse T_2 phase, which is continuously distributed along grain boundaries, has so low corrosion potential in comparison with the ma- trix, this makes the corrosion resistance of the alloy to be deteriorated by anodic dissolution along grain boundaries.
关键词:
AI-Li alloy
,
null
,
null
,
null
LI Zheng
,
LIU Honglin
,
CHENG Zhaonian
,
CHEN Nianyi
,
Shanghai Institute of Metallurgy
,
Academia Sinica
,
Shanghai
,
ChinaZHOU Jiaju
,
Institute of Chemical Metallurgy
,
Academia Sinica
,
Beijing
,
China CHEN Nianyi
,
Professor
,
Shanghai Institute of Metallurgy
,
Academia Sinica
,
Shanghai 200050
,
China
金属学报(英文版)
The formability of complex flourides has been studied by chemical bond parameter-pattern recognition method. In a multi-dimensional space spanned by ionic radius, ionic polarizability, electronegativity and ionic charge of the metal elements, the binary complex flouride-forming systems and binary flouride systems without complex flouride formation distribute in different regions with a clear-cut boundary. The mathematical models obtained are useful for new complex flouride predicton.
关键词:
complex flouride
,
null
,
null
XING Liqian
,
CHEN Xichen
,
Institute of Physics
,
Academia Sinica
,
Beijing
,
ChinaYANG Gencang
,
ZHOU Yaohe
,
Northwestern Polytechnic University
,
Xi'an
,
ChinaGUO Zhenqi
,
Northwestern University
,
Xi'an
,
China XING Liqian
,
Postdoctoral
,
Institute of Physics
,
Academia Sinica
,
Beijing 100080
,
China
金属学报(英文版)
The glass formability of Ni_(75)B_(17)Si_8 melt and the thermostability of this metallic glass formed from the the melt can be enhanced by eliminating the heterogeneous catalystg. The purification was done by cyclical superheating melt in special glasses and subsequently cyclically superheating it in an electromagnetic levitation apparatus. The purified Ni_(75)B_(17)Si_8 amorphous sample sized up to 20 ~ I0 x 0.5 mm was prepared as four times the thickness of unpurified ones.
关键词:
metallic glass
,
null
,
null
,
null
Shihong LI
,
Ronghui ZHANG
,
Shaoyun FU
,
Xin CHEN and Benlian ZHOU(Institute of Metal Research
,
Academia Sinica
,
Shenyang
,
110015
,
China)Qiyun ZENG(Institute of Applied Ecology
,
Academia Sinica
,
Shenyang
,
110015
,
China)
材料科学技术(英文)
In thjs paper. bamboo fiber has been. on micro scale. investigated as a helical. multi-layered hollow cylinder, the stiffness featu res of bamboo bast fiber were compared with those of a multifilament yarn in traditional fiber-reinforced composite materials, Moreover. a biomimetic model of the reinforce ment of fiber-reinforced composite materials was proposed by imitating the fine structure of bamboo bast fiber. The results show that the comprehensive stiffness properties of the cornplicated fine struc ture of bamboo fiber is superior over those of traditional fiber-reinforced composites.
关键词:
ZHANG Jing
,
CHENG Zhaonian
,
CHEN Nianyi
,
Shanghai Institute of Metallurgy
,
Academia Sinica
,
China CHENG Zhaonian
,
Associate Professor
,
Shanghai Institute of Metallurgy
,
Academia Sinica
,
Shanghai 200050
,
China
金属学报(英文版)
The structure and transport properties in molten NaF have been studied using the method of molecular dynamics simulation. The calculations are based on two models of interionic potentials, which are Fumi-Tosi potential (FT) and the Fumi-Tosi potential without Van der Waals attractive item (FT). The radial distribution function (RDF) and the Na~+ and F~- self-diffusion coefficients have been calculated. The calculated results are in good agreement with the experimental ones. The calculation shows that the two models give nearly identical radial distribution function and self-diffusion coefficient, but the results of FTpotential are a little better than those of FT potential.
关键词:
molten NaF
,
null
,
null
LIU Huizhou
,
YU Shuqiu
,
CHEN Jiayong
,
Institute of Chemical Metallurgy
,
Academia Sinica
,
Beijing
,
China LIU Huizhou
,
Institute of Chemical Metallurgy
,
Academia Sinica
,
Beijing 100080
,
China
金属学报(英文版)
Mechanism of extraction of Fe (III) from sulphate solution by primary amine N1923 and stripping of Fe loaded organic phase with dilute H_2SO_4 was investigated. The organic phase was characterized by FT-IR and photon correlation spectroscopy. The composition of extracted species as well as the content of H_2O in organic phase were determined. The dependence of both the rate of extraction and stripping on the formation of reverse micelle in primary amine (N1923)system has been confirmed. It is shown that the extraction of Fe(III) by primary amine sulphate may be related to the adduct formation or cation exchange reaction under different concentrations of H_2SO_4 in aqueous solution.
关键词:
Fe(III)
,
null
,
null
,
null
Guoqing GU+
,
International Centre for Materials Physics
,
Academia Sinica
,
110015
,
Shenyang
,
ChinaGe CHEN
,
College of Systems Science and Systems Engineering
,
Shanghai Institute of Mechanical Engineering
,
200093
,
ShanghaiK.W.Yu
,
Department of Physics
,
Chin
材料科学技术(英文)
We build the perturbation expansion method for nonlinear composite media and extend the EMA for nonlinear effective conductivity. Using the solutions of boundary-value problems of a cylindrical in- clusion, we derive formulae for nonlinear effective conductivity.
关键词:
effective medium approximation
,
null
Wenge LIU+
,
Min ZHU
,
Dazhi YANG
,
Dept. of Materials Engineering
,
Dalian University of Technology
,
Dalian
,
116024
,
ChinaZhongguang WANG
,
State Key Laboratory for Fatigue and Fracture of Materials
,
Institute of Metal Research
,
Academia Sinica
,
Shenyang
,
11001
材料科学技术(英文)
The thermal-mechanical (T-M) cycles at constant strain of a polycrystalline CuZnAl alloy have been studied in the. present work. In-situ optical microscopic observations have been made to reveal the features of the phase transitions during T-M cycling. The variation of stress-temperature (S-T) curves and electrical resistance-temperature (R-T) curves accompanying with T-M cycling have been measured by tensile test and electrical resistance measurements. It has been found that the polycrystalline CuZnAl alloy shows apparent morphology changes and properties variations in the first cycle during T-M cycling which is called the first cycle effect in the present work. The stable transformation procedure in the T-M cycle is: martensiteparent phase +residual acicular martensite. This residual martensite possesses the character of stress-induced martensite.
关键词:
CuZnAl shape memory alloy
,
null
,
null
Ju LUO
,
Xingzhao DING
,
Benpei CHEN and Jie KONG(Institute of Solid State Physics
,
Academia Sinica
,
Hefei
,
230031
,
China)Yuanda DONG(Dept. of Metallurgy and Materials
,
Shanghai University of Technology
,
Shanghai
,
200072
,
China)
材料科学技术(英文)
The development of microstructure of nanometer TiO2 powders prepared by a sol-gel process was systematically studied. Grain growth was mon itored using X-ray diffraction (XRD) and transmission electron microscopy (TEM). and the Debye temperature of anatase crystallites was determined. It was found that the grain size of the powders increased slowly with annealing temperature up to 773 K. but grew rapidly in the temperature range of 773-1273K. The activation energies (Ea) for the growth of anatase crystallites in the two temperature regions were calculated to be 16 and 90 kJ / mol, respectively. The Debye temperatures of nanocrystalline anatase powders were all lower than that of microcrystalline anatase. which implies that the bonding force between Ti and O atoms in nanocrystalline TiO2 shourd be smaller than that in microcrystalline state. However. it was noted that the Debye temperature of nanocrystalline anatase increased with the decrease of grain size. This may be attributed to the enhancement in atomic bonding force due to the existence of high surface tension in nanocrystalline powders
关键词:
Zhidong ZHANG+
,
Changheng WU
,
Zhenchen ZHONG
,
Xiaokai SUN
,
Y.C. Chuang
,
Institute of Metal Research
,
Academia Sinica
,
Shenyang
,
110015
,
China
材料科学技术(英文)
In present investigation exchange interactions of Pr_(n+1)Co_(3n+5)B_(2n)-type compounds have been evalu- ated in the light of molecular-field theory. The exchange interactions and ferromagnetism in these compounds are discussed in terms of lattice parameters and interatomic distance between Co atom.
关键词:
Pr-Co-B alloy
,
null
,
null