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INFLUENCE　OF　ENVIRONMENT　ON　TENSILE　BEHAVIOR　OF　Ni_3Al　SYNTHESIZED　UNDER　COMPRESSION

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Acta metallurgica Sinica(English Letters) 1996年第1期9卷 12-16页

作者： LI Gang WANG Zhongguang LI Guangyi(State key laboratory of Fatigue and Fracture for Materials,{2. of metal research,chinese academy of sciences,shenyang 110015,china)V.OVCHARENKO({2. of Strength Physics and Materials Science,Russian academy of Inst of metal research Chinese Acad of Sciences Shenyang China

Self propagating high temperature synthesis(SHS) under compression was utilized to obtain an intermetallic compound Ni_3 Al by using elemental *** microstructure of the SHS product was observed by optical microscopy(OM) and scanning electron microscopy(SEM).The results reveal that the SHS Ni3Al is a single-phase polycrystalline alloy wilh LI2.crystal *** tests were conducted from room temperature to 800℃ both in air and in *** results show that the SHS Ni_3Al exhibits an anomalous temperature dependence of ultimate tensile *** ultimate tensile strength in vacuum is much higher than that in air over the whole temperature *** surfaces are characterized by the brittle grain boundary fracture and the intergranular fracture mode can not be affected markedly by the test environment.

关键词： Ni_3Al synthesis environment tensile behavior

Effects of icosahedral phase formation on the microstructure and mechanical improvement of Mg alloys:A review

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Progress in Natural Science:Materials International 2012年第5期22卷 364-385页

作者： D.K.Xu,E.H.Han State key laboratory for Corrosion and Protection,{2. of metal research,chinese academy of sciences,62.Wencui Road,shenyang 110016,china State key laboratory for Corrosion and Protection Institute of Metal Research Chinese Academy of Sciences 62 Wencui Road Shenyang 110016 China

Icosahedral phase(I-phase) is a relatively excellent strengthening phase in Mg *** on their volume fraction,the yield strength of Mg-Zn-Y-Zr alloys can vary from 150 to 450 MPa at room ***,the formation of I-phase has been considered as one of the most effective methods for developing high strength lightweight Mg alloys for automotive and aerospace *** this review article,a series of {2. work about I-phase containing Mg alloys have been systematically investigated including I-phase formation mechanism and their effects on mechanical properties of Mg *** emphases have been given to:(1) Structure of I-phase and its orientation relationship with the a-Mg matrix.(2. Influence of alloying elements and solidification conditions on I-phase formation.(3) Effects of I-phase on microstructural evolution and mechanical improvement of Mg-Zn-Y-(Zr) ***,the applications of I-phase for the mechanical improvement of other Mg alloys such as AZ91 and super-lightweight Mg-Li alloys are also reviewed.

关键词： Icosahedral phase Mg alloys Mechanical properties Microstructural evolution

Ferromagnetic Fe-based Amorphous Alloy with High Glass-forming Ability

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Journal of Materials Science & Technology 2001年第2期17卷 260-262页

作者： Min XU, Mingxiu QUAN and Zhuangqi HU State key laboratory for RSA,{2., chinese academy of sciences, shenyang 110016, china Lizhi CHENG and Kaiyuan HE School of Materials and metallurgy, Northeastern University, shenyang 110004, Ch chinese Acad Sci Inst Met Res State Key Lab RSA Shenyang 110016 Peoples R China Northeastern Univ Sch Met & Mat Shenyang 110004 Peoples R China

A ferromagnetic amorphous Fe73Al4Ge2.b1P10C6B4 alloy with high glass-forming ability was synthesized by melt spinning. The supercooled liquid region before crystallization reaches about 65.7 K. The crystallized structure consists of alpha -Fe, Fe3B, FeB, Fe3P and Fe3C phases. The Fe-based amorphous alloy exhibits good magnetic properties with a high saturation magnetization and a low saturated magnetostriction. The crystallization leads to an obvious decrease in the soft magnetic properties.

关键词： Ferromagnetic Fe-based Amorphous Alloy with High Glass-forming Ability Am GFA

2.5-dimensional angle potential field algorithm for the real-time autonomous navigation of outdoor mobile robots

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Science china(Information sciences) 2011年第10期54卷 2100-2112页

作者： QIU Quan 1,3 & HAN JianDa 2.1 Beijing research Center of Intelligent Equipment for Agriculture,Beijing 100097,china 2.State {2. laboratory of Robotics,shenyang institute of Automation,chinese academy of sciences,shenyang 110016,china 3 National research Center for Intelligent Agricultural Equipment,Beijing 100097,china 1. Beijing research Center of Intelligent Equipment for Agriculture Beijing 100097 China3. National Research Center for Intelligent Agricultural Equipment Beijing 100097 China2. State Key Laboratory of Robotics Shenyang Institute of Automation Chinese Academy of Sciences Shenyang 110016 China

A new real-time algorithm for the autonomous navigation of mobile robots equipped with laser scanners is proposed in this *** from the existing algorithms designed for 2.dimensional navigation problems,the new algorithm introduces the height information of the obstacles into the guidance process and behaves as a 2.5-dimensional angle potential field algorithm (2.5D-APF) to fulfill the navigation requirements under complex outdoor terrain ***,one laser scan is partitioned into two kinds of function sectors: guidance sector and inspecting ***,the guidance sector and the inspecting sectors are reconstructed to form a virtual guidance scan,where the 2.5D information is taken into ***,the conventional APF is improved to analyze the virtual guidance scan and generate the navigation *** new algorithm is tested on a tracked mobile robot,and the experimental results validate the proposed algorithm.

关键词： robot 2.5-dimensional outdoor real-time autonomous navigation

FABRICATION OF Ti/SiC MMCs BY VACUUM HOT PRESSING WITH AID OF HYDROGEN

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Acta metallurgica Sinica(English Letters) 1998年第4期11卷 307-312页

作者： C.H. Zhou K. Yang and Y.X. Lu (Liaoning key Lab for Hydrogen and Materich, institute of metal research, The{2., Shenyan 110015, china) Inst of metal research The Chinese Acad of Sciences Shenyang China

In order to alleviate the severe interface reaction, which is likely to occur during the fabrication of continuous SiC fiber reinforced titanium matrix composite, hydrogen was temporarily introduced in the fabrication to lower the consolidation temperature of Ti/SiC composites in the present work. Effects of different fabrication conditions, with or without hydrogen, on the bonding state and the matrix microstructure were investigated. In-situ hydrogenation method was found to larpely improve the interface bonding of the composite, and full consolidation could be achieved at 750 or even 700° C more than 100°C lower than the normal fabrication temperature of Ti/SiC composite, which consequently reduced the interfacial reaction layer between Ti matrix and SiC fiber. Different hydrogenation condition led to different matrix microstructure. In order to avoid the embrittling effect of residual hydrogen on the composite,Ti/SiC composite needs to be held in vacuum at the fabrication temperature for longer time after consolidation.

关键词： Ti/SiC composite hydrogen microstructure

MICROFRACTOGRAPHY OF NEAR-THRESHOLD FATIGUE CRACK PROPAGATION IN DUAL-PHASE STEELS

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Acta metallurgica Sinica(English Letters) 1992年第5期5卷 385-389页

作者： ZHENG Yesha WANG Zhongguang AI Suhua State key laboratory of Fatigue and Fracture for Materials,{2. of metal research,Academia Sinica,shenyang,110015,china Inst of metal research Acad Sinica Shenyang China

SEM microfractography of near-threshold fatigue crack propagation were carried out in the dual-phase steels of 3 martensite morphologies and 6 volume fractions of martensite (V_m). All of them are featured by cyclic cleavage characteristics in near-threshold region,i.e.,main- ly controlled by mode Ⅱ *** the higher ΔK regions,the fracture surfaces are character- ized by mixed modes including cyclic cleavage facets,two types of secondary cracks and striations,etc..The roughness-induced crack closure of fracture surface is attributed primarily to extreme high fatigue crack growth threshold values.

关键词： dual-phase steel threshold value fatigue crack growth fractograph near-threshold

HYDROGEN PERMEATION AND DIFFUSION IN ALLOY INCOLOY 903

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Acta metallurgica Sinica(English Letters) 1993年第3期6卷 163-167页

作者： XU Jian SUN Xiukui CHEN Wenxiu LI Yiyi State key laboratory of RSA,{2. of metal research,Academia Sinica,china research assistant,{2. of metal research,Academia Sinica,shenyang 110015,china Inst of metal research Acad Sinica Shenyang China

Permeability and diffusivity of hydrogen in Fe-Ni-Co based superalloy lncoloy 903 were measured over the temperature range of 2.0 to 42.℃ using a gaseous permeation technique. The effect of strengthening phase γ' precipitated after being aged on the hydrogen permeation and diffusion was *** was indicated that the permeability and diffusivity of hydrogen in the alloy hardly depend on heat treatment condition and are not af- fected by γ' phase precipitated after being *** relationships between the permeability and diffusivity of hydrogen and the temperature can be respectively expressed as Φ=9.36×10^(-5)exp[-54.2.(kJ/mol)/RT]mol/m·s·MPa^(1/2.and D=4.2.×10^(-7)exp[-49.07(kJ/mol)/RT]m^2.s.

关键词： hydrogen permeation hydrogen diffusion superalloy precipitation phase Incoloy 903

Geochemistry of high-Mg andesites from the early Cretaceous Yixian Formation, western Liaoning: Implications for lower crustal delamination and Sr/Y variations

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Science china Earth sciences 2006年第9期49卷 904-914页

作者： WANG Xiaorui1, GAO Shan1,2. LIU Xiaoming1, YUAN Honglin1, HU Zhaochu1, ZHANG Hong1,3 & WANG Xuance4 1. State key laboratory of Continental Dynamics, Department of Geology, Northwest University, Xi`an 710069,{2. 2. State key laboratory of Geological Processes and Mineral Resources,{2. University of Geosciences, Wuhan 430074,{2. 3. shenyang institute of Geology and Mineral Resources, shenyang 110032.{2. 4. Guangzhou institute of Geochemistry, chinese academy of sciences, Guangzhou 510640,{2. 1. State key laboratory of Continental Dynamics Department of Geology Northwest University Xi’an 710069 China 2. State key laboratory of Geological Processes and Mineral Resources China University of Geosciences Wuhan 430074 China 3. shenyang institute of Geology and Mineral Resources Shenyang 110032 China 4. Guangzhou institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China

85 volcanic rocks of the Yixian Formation from the Sihetun type section werecollected and analyzed for geochemical and isotopic compositions. Major element compositionsindicate that the Sihetun volcanic rocks are high magnesium andesites with some basalts occurring atthe bottom of section. The Sihetun high magnesium andesites (SiO_2.= 52.82.59.31 wt%, Al_2._3=14.15-16.35wt%) show many characteristics of adakites such as depletion in heavy rare-earth elements(HREE; Yb = 1.03-1.88 μg/g) and Y(12.2. μg/g) and high Sr (62.-132. μg/g) and Sr/Y(32.88), withhigh La_N/Yb_N ratio (10-2.). They share similar major and trace element characteristics to volcanicrocks from the Xinglonggou Formation except their lower Nd isotope ratios (^(143)Nd/^(144)Nd(130Ma) = 0.5118-0.5119, ε_(Nd) (130Ma) = -11.6-13.8, ^(87)Sr/^(86)Sr (130 Ma) = *** were interpreted in a way that eclogite that formed at the base of thickened Archean lowercrust of the North china craton foundered into the convecting mantle and subsequently melted andinteracted with peridotite. However, compared to the Xinglonggou volcanic rocks, the source of theSihetun magma contained more ancient continental crustal material in order to explain its evolved Ndisotopes. The age of the Sihetun Formation was 12. to 130 Ma, and this indicates that delaminationlasted to the early Cretaceous period. The Sr contents and Sr/Y ratios of the Sihetun high-Mgandesites show significant negative correlations with SiO_2.for samples with SiO_2.> 56%. Thesesuggest that the Sr and Sr/Y values were reduced due to fractional crystallization of ***, the effect of crystallization on volcanic Sr and Sr/Y ratio has to be taken intoaccount.

关键词： High-Mg andesite, Adakite, Yixian Formation, North china Craton, delamination.

Simulation of Tensile Behavior of Nickel Foam

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稀有金属材料与工程 2011年第S3期40卷 224-227页

作者： Zhao Mingjuan 1, Zhang Xiaolan 1, Zhao Longzhi 1,3, Zhang Jinsong 2.1 key laboratory of Ministry of Education for Conveyance and Equipment, East{2. Jiaotong University, Nanchang 330013,{2. 2.4}, chinese academy of sciences, shenyang 110016,{2. 3 key laboratory of Superlight Materials & Surface Technology, Ministry of Education, Harbin Engineering University, Harbin 150001,{2. E china Jiaotong Univ Key Lab Minist Educ Conveyance & Equipment Nanchang 330013 Peoples R China Harbin Engn Univ Minist Educ Key Lab Supertight Mat & Surface Technol Harbin 150001 Peoples R China chinese Acad Sci Inst Met Res Shenyang 110016 Peoples R China

Nickel foam is widely used as the electrode, the catalyst carrier, sound absorption material and other application fields. The tensile behavior of the open cell nickel foam which is one of the most important parameters in the design process was investigated with the finite element method based on ANSYS software in this paper. The effects of strain rates and temperature on the yield strength of the nickel foam were obtained. The results show that the yield strength exhibit a nonlinear reduction with the increases of the temperature for the elastic bending of the struts of the reinforcement grew quickly depending on the temperature. However, the yield strength increases slowly with the improvement of the strain rate because the strain rate neither change the internal structure and properties such as the porosity and the aperture, nor alter the external circumstance in order to change the internal properties such as the temperature. The results of the simulation accord with those of the experiments, which is very important to understand the tensile behavior of the foam materials.

关键词： nickel foam ANSYS yield strength temperature strain rate