HONG Youshi Institute of Mechanics
,
Academia Sinica
,
Beijing
,
ChinaW.R.TYSON B.FAUCHER Physical Metallurgy Research Laboratories
,
CANMET
,
Ottawa
,
Canada HONG Youshi Institute of Me-chanics
,
Academia Sinica
,
Beijing 100080 China
金属学报(英文版)
The inclusion parameters,fracture surface morphology and void growth characteristics of ten- sile and fracture toughness specimens of 2.25Cr-1Mo steels with and without rare-earth (RE)additions have been investigated by quantitative metaltography(QTM),scanning elec- tron microscopy(SEM)and energy dispersive spectroscopy(EDS).There is a substantially higher density of inclusions in the RE-treated steel,which has lower values of fracture proper- ties including critical values of COD and J integral(δ_c and J_(IC)),fracture strain(ε_f) and Charpy V-notch energy(CVN).The fracture surface of the RE-treated steel comprises equiaxed dimples of diameters comparable with its inclusion spacing,whereas for the non-RE-treated steels,a wide range of dimple sizes is found with average diameter much smaller than the corresponding inclusion spacing.The investigation indicates that the lower values of fracture properties for the steel with RE at room temperature may be ascribed to its large content of RE-containing inclusions.
关键词:
Cr-Mo steel
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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
LIANG Yong LI Ruiguo Institute of Metal Research
,
Academia Sinica
,
Shenyang 110015
,
ChinaInstitute of Corrosion and Protection of Metals
,
Aademia Sinica
,
Shenyang
,
110015
,
China
材料科学技术（英文）
Recent advances in laser coating technology including laser cladding,laser surface alloying and laser vapour deposition in China are reviewed in this paper.
关键词:
laser
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null
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null
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null
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null
Yang LUO
材料科学技术（英文）
Due to continued growth in key markets, a broadening of application base and performance improvements, the market demands of NdFeB magnet increased steadily in 1998, and the global output of sintered NdFeB magnet exceeded 10,000 t, in spite of the economic recession in Asia. In 1998 China produced 3,850 t sintered NdFeB block magnet, with an annual growth rate of +22% over the output in 1997.
关键词:
Shaoxiong ZHOU
材料科学技术（英文）
The discovery of the first Fe-based ferromagnetic amorphous alloy in 1966 had made an impact on conventional magnetic materials because of its unique properties. Since then, a number of amorphous magnetic materials have been successfully developed and used in a wide variety of applications. A brief review of R & D activities on amorphous soft magnetic materials in China is given from the beginning to the present in a somewhat chronological order, followed by a brief introduction to their applications on electric and electronic industries. An analysis and a prospect of Chinese market of such amorphous materials are also presented.
关键词:
