LIU Ning CUI Kun Huazhong University of Science and Technology
,
Wuhan.China DENG Zonggang Hefei University of Technology
,
Hefei
,
China CHENG Benpei KONG Jie Institute of Solid State Physics
,
Academia Sinica
,
Hefei
,
China Doctorate student
,
Department of Mechanical Engineering No.2
,
Huazhong University of Science and Technology
,
Wuhan 430074
,
China
金属学报(英文版)
Microstructure of the deepest zone of high speed steel W6Mo5Cr4V2(M2)melt after laser fu-sion was found to be so fine as the ehill zone of a solidified ingot.When narrower chill zoneformed,the long columnar dendrites grow into the melt and then the fine equiaxed cellularstructure appears in upper melt region nearly surface.The substructure of cellular grains anddendrites was observed to consist of martensite and retained austenile,while the carbides asM_6C_■ Cr_7C_3 and MC distributed at their boundaries.It is believed that the highermicrohardness up to HV_(0.1)=865-960 of the laser fused structure of the alloy is due to the oc-currence of martensite.
关键词:
High speed steel W6Mo5Cr4V2(M2)
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null
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null
LIANG Yong LI Ruiguo Institute of Metal Research
,
Academia Sinica
,
Shenyang 110015
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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
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
ZHANG Shourong
钢铁研究学报(英文版)
One of the problems encountered in 60′s to 80′s of 20th century in China′s steel industry was short life of blast furnace shaft as well as the excessive erosion of blast furnace hearth. A series of research work was carried out in order to extend blast furnace campaign life. The concept of research and development was integrated in the construction of BF (blast furnace) No5 at WISCO (Wuhan Iron and Steel Corporation), and in October, 1991, the BF No5 was blown in. The blast furnace has worked smoothly for more than 15 years without any medium repair even guniting. It is expected that the campaign life of BF No5 would be longer than 16 years with a production over 11 000 t per unit inner volume (m3). A new blast furnace with an inner volume of 3 400 m3 is under construction, and is designed with a campaign life of 20 years without any medium repair. The campaign life of blast furnaces in China has been extended in recent years.
关键词:
blast furnace;campaign life;erosion
