Zhiheng LU Department of Physics
,
Beijing Normal University
,
Beijing
,
100875
,
ChinaDachan WANG Yan LUO Institute of Low Energy Nuclear Physics
,
Beijing Normal University
,
Beijing
,
100875
,
China
材料科学技术（英文）
It was reported that due to the non-linear electrical phenomena,the super-saturated arsenic in silicon single crystalline precipitates during post processing at low temperatures to form different structures.The structure with spatial period of 1.7 to 2.3 nm was observed firstly by TEM on the sample.
关键词:
nano-structure
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null
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null
GE Yunlong YANG Yuansheng JIAO Yuning HU Zhuangqi Institute of Metal Research
,
Academia Sinica
,
Shenyang
,
ChinaGAO Yunyan JIA Guanglin Northeast University of Technology
,
Shenyang
,
China associate professor
,
Institute of Low Energy Nuclear Physics
,
Beijing Normal University
,
Beijing
,
100875
,
China
金属学报(英文版)
A new technique of centrifugal casting under electromagnetic field was firstly proposed and investigated.Taking a heat resisting alloy steel 25Cr20Ni and an Al-Cu alloy as examples,products,though their length,diameter and wall thickness are varied,re- vealed so superior macrostructures that the mechanical properties are much improved in comparison with conventional centrifugal casting.
关键词:
electromagnetic field
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null
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null
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null
QIAO Lijie LIU Rui XIAO Jimei University of Science and Technology Beijing
,
Beijing
,
China
金属学报(英文版)
The effects of stress components on nucleation sites and propagation directions of stress cor- rosion cracks in brass were investigated with specimens under mode Ⅱ and mode Ⅲ loadings. The results indicated that under mode Ⅱ loading,stress corrosion cracks nucleated on the site with maximum normal stress component and propagated along the plane perpendieular to the maximum normal stress,under mode Ⅲ loading,the stress corrosion crack was not evident on the 45°plane due to the general corrosion in aqueous solution with high NH_4OH concentra- tion,while stress corroded in aqueous solution with low NH_4OH concentration, numerous cracks with spacings of 10—150μm were found on the 45°plane with maximum normal stress and no stress corrosion cracks was observed on the plane with maximum shear stress.
关键词:
stress corrosion cracking
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null
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null
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null
Y.T. Liu
,
X.J. Guan
,
X.M. Shen
,
X.F. Ma
,
L.J.Wang
,
null
,
null
,
null
,
null
金属学报(英文版)
The microstructures and their kinetics of normal
grain growth are simulated using different Monte Carlo (MC)
algorithms. Compared with the relative figures and the theoretical
normal grain growth exponents of n=0.5, the effects of some
factors of MC algorithm, i.e. the lattice types, the methods of
selecting lattice sites, and the neighbors selection for energy
calculations, on the simulation results of grain growth are studied.
Two methods of regression were compared, and the three-parameter
nonlinear regression is much more suitable for fitting the grain
growth kinetics. A better model with appropriate factors included
triangular lattice, the attempted site randomly selected, and the
first and second nearest neighbors for energy calculations is
obtained.
关键词:
Grain growth
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null
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null
Materials Letters
beta-quartz, stable at room temperature and under normal pressure, is obtained by high-pressure quenching, using an all-silicon ZSM-5 zeolite as the reaction precursor and characterized by means of X-ray diffraction.
关键词:
Science and Engineering of Composite Materials
The impact toughness of normal bamboo, reformed bamboo and reformed bamboo reinforced composites was studied comparatively by using a computerized Automatic Impact Testing System. It is found that the impact toughness of normal bamboo is dependent on the direction of the impact load. If the impact load is applied in the radial direction of the bamboo culm, the specimen impacted on the pith-ring has a much higher impact toughness than those impacted on the rind side. The impact toughness of reformed bamboo is somewhat lower than that of normal bamboo when most static mechanical properties are increased. The experimental results reveal that one of the technical parameters of reformed bamboo, the compressive ratio, is closely related to its impact toughness. However, the composition of reformed bamboo with glass fabric and aluminum sheets can improve the impact properties of reformed bamboo composites to a satisfactory extent while maintaining the superiority of their static mechanical properties.
关键词:
reformed bamboo;impact toughness;dynamic fracture
Applied Physics Letters
The magnetocaloric effect (MCE) at the antiferromagnetic (AF) to ferromagnetic (F) phase transition in Mn1.05Ni0.85Ge and CrO1.86F0.14, and the MCE at the F-AF transition in Tb3Co have been investigated. Mn1.05Ni0.85Ge and CrO1.86F0.14 are found to exhibit the inverse MCE whereas the MCE of Tb3Co is normal. For these compounds, the dependence of the transition temperature on the applied magnetic field B has been studied. A thermodynamical analysis is presented of the sign of the magnetic-entropy change in these three compounds which are representatives of two different types of B-T diagrams. Other possible B-T diagrams are discussed and the analysis is extended to AF-F and F-AF phase transitions reported in literature. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4729122]
关键词:
