ZHA NG Xiumu QI Yan ZHONG Jiaxiang GUO Yunyi ** Institute of Metal Research
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Academia Sinica
,
Shenyang
,
110015
,
China.Beijing University of Science and Technology
,
Beijing
,
100081
,
China. To whom correspondence should be addressed.
材料科学技术（英文）
The effect of compressive deformation tested above the M_s temperature on the martensite morphology in Fe-Ni-C alloys has been studied.In the Fe-30Ni-0.12C alloy,the M_s temperature is -50℃ The cylindrical specimens were compressively deformed at -40℃.The strain rates were 10,20,30 and 40%.X-ray analysis and metallographic examination showed that no strain-induced martensite was found.After quench- ing to -53℃,some thin plates and unusual morphologies of lenticular martensites with bent and/or broken mid-ribs were observed.In the Fe-30Ni-0.34C alloy,the M_s temperature is -120℃.Compressive deformation with different strain rates were carried out at room temperature. After quenching to the liquid nitrogen temperature, some bent thin plate matensites(unbroken)occur- red.The transformed twins in bent plate were also bent and nearly parallel to the γ-α'interfaces. Orientation relationship between austenite and bent martensite has been examined by means of trans- mission electron microscope.It was proved that these unusual morphologies are inherent in the compressive pre-deformed austenite.
关键词:
martensitic transformation
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QIAO Lijie LIU Rui XIAO Jimei University of Science and Technology Beijing
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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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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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