YI Jianzhang Shenyang Institute of Aeronautical Engineering
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Shenyang
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ChinaYANG Zhi'an ZHU Shijie WANG Zhongguang Institute of Metal Research
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Academia Sinica
,
Shenyang
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China lecturer
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Department of Safety Engineering
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Shenyang Institute of Aeronautical Engineering
,
Shenyang 110031
,
China
金属学报(英文版)
Vertical section method has been used to measure the fractal dimension of cyclic creep frac- ture surfaces of rotor steel 34CrMoA at 550℃.The relationship between fractal dimension and cyclic creep properties has been analyzed.The fractal dimension is dependent upon the power product of minimum creep rate and rupture time,and satisfies the linear function with rupture strain.
关键词:
cyclic creep
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HUANG Yan
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MA Longxiang Northeast Universtity of Technology
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Shenyang
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China lecturer
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Department of Metalforming
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Northeast University of Technology
,
Shenyang 110006
,
China
金属学报(英文版)
Diffusion bonding of supcrplastic Al alloy LC4,with prior surface treatment of organic solution protecting coating after electroplishing and stainless steel wool brushing,was performed by Gleeble test machine under conditions ranged 490—530 ℃,1.0—3.0 MPa. 30—180 min and vacuum of 1.0×10~(-3) Pa.The joints were examined to have similar strength and microstructure to the base metal Discussion was made on the effect of superplastic treatment on bonding.The micromechanism for diffusion bonding of super- plastic metal was suggested as the migration of original bond interfaces caused by atomic diffusion and grain growth. Experimental results for the alloy as quench-aged state were presented to compare with the superplastic one.
关键词:
superplasticity
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LI Xiaogang CHEN Hua YAO Zhiming LI Jin KE Wei Institute of Corresion and Protection of Metals
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Academia Sinica
,
Shenyang
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China lecturer
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Institute of Corrosion and Protection of Metals
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Academia Sinica
,
Shenyang 110015
,
China
金属学报(英文版)
The hydrogen attack of austenitic stainless steel 304 exposed to hydrogen under the pressure of 5 MPa at 733 K for 2×10~4 h in service was detected.The microstructure has been studied by SEM and TEM.Hydrogen was determined with molten samples which had tempered at.573,673,773,873,and 973 K for 6 h.The results showed that hydrogen attack in this steel was due to methane bubbles which resulted in occuring of Cr_(23)C_6.Thermodynamic analysis of hydrogen attack for stainless steel 304 was discussed.
关键词:
hydrogen attack
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ZHANG Sanhong HE Xinlai CHU Youyi~* KE Jun University of Science and Technology Beijing
,
Beijing
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China lecturer
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Department of Materials Physics
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University of Science and Technology Beijing
,
Beijing 100083
,
China
金属学报(英文版)
The behaviour of baron segregation at grain boundaries in Fe-3% Si has been studied by means of particle tracking autoradiography(PTA).The results indicate that the tendency of equilibrium segregation of B at grain boundaries in Fe-3% Si is higher than that in austenitic alloys.No observable nonequilibrium segregation of B at grain boundaries was revealed in Fe-3% Si alloy during cooling and isothermal holding.The binding energy between boron at- oms and grain boundaries is 55.7±1.7 kJ/mol.Based on the complex mechanism of B segre- gation of quenching-induce-nonequilibrium segregation,different behaviours of B segrega- tion in γ-Fe and bcc Fe-3% Si alloy were discussed.
关键词:
Boron
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JIANG Hai TAO Kun LI Hengde Tsinghua University
,
Beijing
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China lecturer
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Department of Materials Science and Engineering
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Tsinghua University
,
Beijing 100084
,
China
金属学报(英文版)
BN films,synthesized by ion beam assisted deposition,were analysed by RBS,AES, IR spectra and TEM.Formatiom of c-BN phase was shown not only by IR spectra at absorption peak of 1100 cm~(-1),but also by electron diffraction pattern.The results of AES demonstrate an effect of N~+ implantation near the film surface.The deposited films consist of three layers,i.e.,ion implantation layer,film layer and mixed intermediatelayer, according to the difference of concentration.The micro-Knoop hardness of the film is 25—35 GPa.
关键词:
ion beam assisted deposition
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LIU Jianhong HE Shiyu YAO Mei Harbin Institute of Technology
,
Harbin
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China lecturer
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Depatment of Metallic Materials
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Harbin Institute of Technology
,
Harbin 150006
,
China
金属学报(英文版)
The growing process of thermal fatigue cracking,in steel 3Cr2WSV was observed under desk SEM fitted with sell-made minisized device for thermal faligue test.Before the growing of thermal fatigue crack,the main crack tip reveals to blunt firstly,and some holes and uncontinuous microcraeks occur in front of it.The growth is developed by bridging of main crack together with holes and microcracks.
关键词:
steel 3Cr2W8V
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