GAO Hua CHEN Youxuan LI Ming Shanghai University of Engineering Science
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Shanghai
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ChinaCHEN Dehai Shanghai Dalong Machinery
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Shanghai
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China Associate Professor
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Dept.of Materials
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Shanghai University of Engineering Science
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Shanghai 200051
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China
金属学报(英文版)
The effect of proportional and non-proportional overloading on mode l fatigue crack growth have been studied,and the influences of crack tip plastic zone,crack tip blunting as well as crack closure were discussed.Proportional(model I)overloading may cause more serious crack growth retardation than non-proportional(mixed mode)overloading.Therefore,for estimating the fatigue life of engineering structures to simplify a real overload which may of- ten be non-proportional as a proportional one is not always safe.
关键词:
non-proportional overloading
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Author X.A. Zhang1)
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H.Q. Xia1)
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Z.T. Wu1)
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Y.F. Han1)
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R. Shi2) and G.X. Hu2) \= 1) Mechanical Properties Laboratory
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Beijing Institute of Aeronautical Materials
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Beijing 100095
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China2) The State Education Commission Open Research Laboratory for High Temperature
金属学报(英文版)
Materials and Testing, Shanghai Jiao Tong University, Shanghai 200030, ChinaManuscript received 18 October 1998 The threestage creep behavior of DD3 single crystal superalloy had been studied. The results show that the creeprupture properties of DD3 single crystal satisfy the requirements for high performance turbine blade application. The influence of crystal orientation on the creeprupture property of DD3 single crystal was tested and discussed. An engineering criterion to evaluate the regimes of secondary and tertiary creep is proposed, and this method gives a reasonable result for practical applications. The fractography and TEM micrography of the tested specimens had been studied, and it is determined that the glidecontrolled creep is the basic creep mechanism of DD3 single crystal at intermediate temperature, but the thermally activated processes become dominant at higher temperature.
关键词:
threestage creep curve
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新型炭材料
The 2011 Annual World Conference on Carbon (Carbon 2011) was held in Shanghai, China, during 24-29 July, 2011. This conference was hosted jointly by East China University of Science and Technology, University of Shanghai for Science and Technology, and Institute of Coal Chemistry Chinese Academy of Sciences. About 800 attendees from 42 countries/regions participated in this conference, and 797 papers were accepted for presentation, including 5 plenary lectures, 42 keynote lectures, 280 oral presentations, and 470 posters, involving 10 topics: graphene; nanocarbon, carbon for energy storage and conversion, porous carbon and adsorption, carbon fiber and composites, precursor/carbonization and graphitization, computation and modeling, bio-carbon and safety, novel experimental techniques and characterization, bulk carbon and industrial applications. Research and development of nanocarbons are quite active and in particular, graphene received tremendous interest. Rapid progress has also been made on the electrochemical properties, energy conversion and energy storage applications of carbon materials.
关键词:
材料导报
多相材料是材料研究发展的必然结果。提出多相材料的研究,目的是要拓宽材料研究的视野,主张模糊各类材料的界限,运用纳米材料制备技术,博采各类材料制备工艺之所长,以使用上的要求为材料研究的准则,制作出低成本和高性能稳定性的材料。还强调在考虑材料研究中的问题时,始终以满足使用要求为目标,并不一味地追求材料的高性能,务求创新。提倡用逆向思维来考虑多相材料的研完,研究对象则针对于信息、能源、生物和环保领域的应用。多相材料材料研究About the Research of Multi-phase MaterialsGuo Jingkun (Shanghai Institute of Ceramics,Chinese Academy of Sciences ,Shanghai 200050, China)
关键词:
ZHOU Jiankun LIU Xianghuai CHEN Youshan WANG Xi ZHENG Zhihong HUANG Wei ZOU Shichang Shanghai Institute of Metallurgy
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Academia Sinica
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Shanghai
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China
金属学报(英文版)
The TiN films were synthesized with an alternate process of depositing titanium from a E-gun evaporation source and 40 keV N~+ bombarding onto the target.It is shown from the composi- tion analysis and structure investigations using RBS,AES,TEM,XPS and X-ray diffraction spectrum that the formed fihns are mainly composed of TiN phase with grain size of 30—40 nm and without preferred orientation,the nitrogen content in the film is much less than that in case without N~+ bombarding,and an intermixed region about 40 nm thick exists between the film and the substrate.The films exhibt high microhardness and low friction. ZHOU Jiankun,Ion Beam Laboratory,Shanghai Institute of Metallurgy,Academia Sinica, Shanghai 200050,China
关键词:
TiN film
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W.Xie
金属学报(英文版)
Shanghai No.5 Steel Co., Ltd. has recently introduced a set of 5-ton protective atmosphere electroslag remelting furnace and a set of lO-ton helium-cooling vacuum arc remelting furnace,both of them are the first one of its kind in China. With these equipment, remelting processes about alloy GH4169, GH2132 and GH738 were researched, the process of producing alloy GH4169 by VIM+ VAR + ESR triplex-process was developed, and their effects were discussed.
关键词:
superalloy
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C. Jiang
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Y.B. Chen
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B.S. Wu
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Q.L. Jin
金属学报(英文版)
Temperature field numerical simulation about he heat treatment process curve of large turbine rotor is presented. With simulation software Deform3D in according to the heat treatment processing of China First Heavy Machinery, the details of temperature change at the different location of the rotor is to be found. Once knowing the temperature field change, the duplex grain defect long time existed in large forgings can be solved with a quantitative analysis instead of only the qualitative one. Precondition for small metal samples is brought to simulate microstructure and grain size change of large rotor according to the numerical simulation result. Also, consistent feature with real manufacture is showed from the physical experiment, so that the simulation can be used to not only improve the products process but also prevent wasting unnecessary energy and shorten process periods. The rotor quality is controlled thoroughly with plenty of experiments data.
关键词:
temperature field
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X.F. Zhang
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D.J. Wang
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G. Xie
金属学报(英文版)
The Al/fly ash composites are fabricated by liquid reactive sintering P/M process withfly ash particles as intensifying phases. The reactivity and newly formed phases dur-ing liquid sintering process have been analyzed by combing Thermochemical data basecalculation and XRD characterization. The results show that some of constituents infly ash have reacted with liquid aluminum so that the elemental Si, Fe, Ti as well assome amount of intermetallic compounds occur. The properties of aluminum/fly ashcomposites have been improved. With the fraction of fly ash increase, the compositedensity decreases; the hardness and the modulus of the composite increases, and thecomposite wear resistance are significantly increased. The fly ash reinforced compos-ires represent a sort of low cost product with possible widespread applications in theautomotive, small engine, and electromechanical machinery sectors.
关键词:
aluminum/fly ash composite
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L.I.Mikhoduj (The E. O. Paton Electric Welding Institute
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NAS of Ukraine
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Kiev
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Ukraine)
金属学报(英文版)
Composition and service properties of high - strength low-alloyed steels with 590-980 MPa yield strength,which find an application in Russia, Belorus,Ukraine and other countries of the former USSR in manufacture of welded structures of a powerful mining and transport machinery, are given. Electrodes and wires for main processes of arc welding of these steels have been devel- oped on the basis of a rational use of different systems of alloying (08KhN2GM,08KhNG2M, and also economical systems of type 10G25, ect. ). Main approaches to the technological provess- es of manufacture of structures of high - strength steels are formulated.They are mainly directed to the weakening of de offect of the factors which contribute to a delayed fracture of joints (diffusive hydrogen,unfavourable rates of cooling,level of residual stresses). When there are no stress concentrators (and at a low level of residual stresses) the welded joints of these steels have a good resistance to fatigue and brittle fractures.As a rule, they are prevented with the help of the known approaches.It is shown that in addition to them and due to a proper selection of conditions of welding the life of welded joints of the high - strength steels can be 1. 2 - 1. 4 times in- creased.
关键词:
high-strength steel
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