DUO Liang XU Zuxiong MA Ruzhang Beijing University of Science and Technology
,
Beijing.China Institute of High Energy Physics
,
Academia Sinica
,
P.O.Box 2732
,
Beijing
,
China
金属学报(英文版)
The amorphous Fe_(90-x)V_xZr_(10) alloy after electolytic hydrogenation procedure was studied by means of Mossbauer effect,magnetic measurement.X-ray diffaction and secondary ion mass spectroscopy(SIMS)techniques.The experimental results show that the magnetic properties of amorphous Fe_(90-x)V_xZr_(10) alloy are highly sensitive to the presence of hydrogen. The isomer shift(IS)has a small positive change and the magnetic properties transfer from paramagnetic to ferromagnetic State by hydrogenation,and the effect of hydrogen absorption is to raise Fe magnetic moment(from the increase of saturation maguetization)and Curie temperature T_c from 257 to 384 K.Finally.the considerable increase of magnetic properttes of amorphous Fe_(90-x)V_xZr_(10) alloy by hydrogenation is attributable to the change of hybridization effect between outer electrons of Zr atoms and 3d electrons of Fe atoms.From the results of SIMS experiment,it is concluded that the hydrogen atoms is localized around Zr atoms wheh hydrogen atoms enter into the allor.
关键词:
amorphous alloy
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null
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null
B.W. Wang
,
H. Shen
金属学报(英文版)
Ni-Cr System solar selective thin solid films were prepared by d.c. magnetron reactivesputtering under the atmosphere of O2 and N2. Ni-Cr alloy was chosen as targetmaterial and copper sheets as substrate. Using SEM, Spectrophotometer and Talystepto analyze the relations between the selective characteristic and the structure, theformation and the thickness of the thin films. The aim is to obtain good solar selectivethin films with high absorptance and low emittance, which is applied to flat plate solarheat collectors.
关键词:
solar selective thin film
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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
Douxing LI and Hengqiang YE (Laboratory of Atomic imaging of Solids
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Institute of Metal Research
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Chinese Academy of Sciences
,
Shenyang
,
110015
,
China)
材料科学技术（英文）
The present paper summarizes the current status of high resolution electron microscopy (HREM)and the applications of HREM to materials science and condensed matter physics. This review recounts the latest development of high resolution electron microscope, progress of HREM and the applications of HREM, including the crystal structure determination of microcrystalline materials and characterization of the local structure of the defects and nanostructured materials as well as qualitative and quantitative analysis of the grain boundaries, interfaces and interfacial reactions in the advanced materials by means of HREM in combination with electron diffraction,subnanometer level analysis, image simulation and image processing.
关键词:
SUN Wenqiang
,
CAI Jiuju
,
MAO Hujun
,
GUAN Duojiao
钢铁研究学报(英文版)
As the largest energy consuming manufacturing sector and one of the most important sources of carbon dioxide (CO2) emissions, the China′s iron and steel industry has paid attention to the study of changing trend and influencing factors of CO2 emissions from energy use. The logarithmic mean Divisia index (LMDI) technique is used to decompose total change in CO2 emissions into four factors: emission factor effect, energy structure effect, energy consumption effect, and steel production effect. The results show that the steel production effect is the major factor which is responsible for the rise in CO2 emissions; whereas the energy consumption effect contributes most to the reduction in CO2 emissions. And the emission factor effect makes a weak negative contribution to the increase of CO2 emissions. To find out the detailed relationship between change in energy consumption or steel production and change in CO2 emissions, the correlation equations are also proposed.
关键词:
CO2 emissions
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energy use
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LMDI technique
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steel production
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energy consumption
Applied Physics Letters
The solidification behavior of germanium quenched from the melt at pressure of 2-7 GPa is presented. The solidification parameters of specimen were directly measured under high pressure. The microstructure of specimen was observed by electron microscopy. From the measured undercooling and average grain size, the interfacial free energy and activation energy of crystal growth under high pressures were estimated according to classical nucleation theory. Using high resolution transmission electron microscopy (HRTEM), crystals of sizes ranging from 5 to 100 nm surrounded by an amorphous matrix of germanium were found in those samples which quenched from deeply undercooled melt. (C) 1995 American Institute of Physics.
关键词:
X.Q. Li
,
W.P. Chen
,
W. Xia
金属学报(英文版)
Based on the characteristic of high energy milling and the micromechanics of com-
posite material, a plastic constitutive equation is implemented for milled composite
powders. To check the equation, the extrusion of Ti/Al composite powders prepared
by high energy milling was simulated. It was from the numerical analysis that the pre-
dicted extrusion pressure mounted up with milling time and extrusion ratio increasing,
which was perfect agreement with experimental results.
关键词:
high energy milling
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null
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null
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null
