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Journal of Central South University 2000年第3期12卷 159-161页

作者： LIU Yi lun (college of mechanical and electrical engineering, Central South University, Changsha 410083, china) 1. college of mechanical and electrical engineering Central South University 410083 Changsha China

The effect of key parameters on fatigue life of common metallic components, e.g. steel, aluminium alloy, has been analysed quantitatively. The influential coverage and degree of these parameters have been investigated systematically, some phenomena which can′t be discovered with qualitative analysis method have been revealed, a series of valuable conclusions has been obtained, which would be very beneficial to fatigue resistant design and improvement of anti fatigue ability of metallic components.

关键词： metallic material component fatigue life key parameter effect

Parameters Relevant to Bubble Detachment when Gas-injecting into Polymer Melt Flow Field

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Journal of Wuhan University of Technology(Materials Science) 2005年第1期20卷 68-71页

作者：陈再良 college of mechanical and electrical engineering Soochow University Suz hou 215021 China

The bubble deformation processes were reported when gas was injected into polyme r melt flow field in another paper, the experiments showed that the deformation was severely affected by the volume of the bubble, and in turn, for the different bubbles, several different deformation processes were presented d uring their movement along the flow channel. In addition, we could find that the magnitude of the bubble volume was dependent upon the pressure difference of th e gas injection pressure and the melt pressure. In this paper, more experimental conditions were changed to investigate the parameters relevant to the detachmen t of bubbles from the injection nozzle. The experimental results show that the p ressure difference, the melt flow velocity as well as the melt pressure were all critical for the parameters, such as the bubble detachment time, the maximum bu bble diameters and the magnitude of the bubble volume. The morphology changes of bubble were very large when the flow field was abruptly changed, and the situat ions were more complicated.

关键词： bubble morphology detachment time geometry parameters flow field

Crank conditions and rotatability of 3-RRR planar parallel mechanisms

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Science china(Technological Sciences) 2009年第12期52卷 3601-3612页

作者： LI RuiQin 1 &DAI Jian S 2 1 college of mechanical engineering and Automation,North University of china,Taiyuan 030051,china 2 Department of mechanical engineering,King’s college London,University of London,WC2R 2LS,UK college of mechanical engineering and Automation North University of China Taiyuan 030051 China Department of mechanical engineering King’s College London University of London WC2R 2LS London UK

This paper investigates the rotatability of planar parallel mechanisms by revealing the crank conditions that relate to link *** paper extends the theorem of assemblability and the rotatability criterion and applies these criteria to parallel mechanisms in investigating the crank conditions of a parallel mechanism,leading to classification of three types of crank existing conditions including three-crank’s,six-crank’s and nine-crank’s of 3-RRR planar parallel *** results are summarized as constraint conditions in relation with link parameters with a concluding table and case studies.

关键词： crank rotatability planar parallel mechanism

Description to wear debris boundaries by radar graph fractal method

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Chinese Science Bulletin 2007年第16期52卷 2285-2290页

作者： LIU HongTao1,2 & GE ShiRong1 1 Institute of Tribology and Reliability engineering,china University of Mining & Technology,Xuzhou 221008,china 2 college of mechanical and electrical engineering,china University of Mining & Technology,Xuzhou 221116,china Institute of Tribology and Reliability engineering China University of Mining and Technology Xuzhou 221008 China

In this paper,radar graph fractal method is introduced to describe wear debris boundaries. Research results show that it is a nice way to describe wear debris boundaries. Since the longest axis is selected as the first coordinate axis,its center point selected as the center point of the radar graph,and the co-ordinate value of wear debris boundary selected as the measure parameter,the limitations existing in Yard fractal measure method can be avoided. For any wear debris,its radar graph fractal dimension value is one and only,and as the wear debris shape changes from round to strip,the radar graph fractal dimension value also changes from low to high,showing strong uniqueness and independence. Due to the fact that the researched wear debris is gotten in different wear states,the results also prove that radar graph fractal dimension value is correlated with frictional pairs work condition and wear state. Radar graph fractal method is compared with Yard fractal measure methods,and results show that ra-dar graph fractal dimension values gotten from different wear debris have enough value grads to avoid effect of errors,and provide higher sensitivity for wear debris shape. This paper also discusses the influencing factors for radar graph fractal method. With the increase of the decomposing degree value,the radar graph fractal dimension tends to keep stable at one certain value,showing the typical characteristic of the fractal theory. All this proves that radar graph fractal method is an effective description method for wear debris boundaries.

关键词：磨粒边界雷达图表分形法

An Expert System in FRP Composite Material Design

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Journal of Materials Science & Technology 2001年第5期17卷 556-560页

作者： Qingfen LI, Zhaoxia CUI and Weimin WANG college of mechanical & electrical engineering, Harbin engineering University, Harbin 150001, china Jianhua GAO Department of mechanical engineering, Shanghai Jiao Tong University, Shanghai 200030, china Harbin Engn Univ Coll Mech & Elect Engn Harbin 150001 Peoples R China Shanghai Jiao Tong Univ Dept Mech Engn Shanghai 200030 Peoples R China

An expert system prototype for fibre-reinforced plastic matrix (FRP) composite material design, ESFRP, has been developed. The system consists of seven main functional parts: a general inference engine, a set of knowledge bases, a material properties algorithm base, an explanation engine, various data bases, several function models and the user interface. The ESFRP can simulate human experts to make design scheme for fibre-reinforced plastics design, FRP layered plates design and FRP typical engineering components design. It can also predict the material properties and make strength analysis according to the micro and macro mechanics of composite materials. A satisfied result can be gained through the reiterative design.

关键词： An Expert System in FRP Composite Material Design FRP

MOTION ANALYSIS AND DESIGN OF ACCUMULATOR FOR HYDRAULIC ROCK DRILL

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中国有色金属学会会刊：英文版 1996年第2期6卷 148-151页

作者： Liu Shixun(college of mechanical and electrical engineering, Central South University of Technology, Changsha 410083) CENT S UNIV TECHNOL COLL MECH & ELECT ENGNCHANGSHA 410083PEOPLES R CHINA

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ＭＯＴＩＯＮＡＮＡＬＹＳＩＳＡＮＤＤＥＳＩＧＮＯＦＡＣＣＵＭＵＬＡＴＯＲＦＯＲＨＹＤＲＡＵＬＩＣＲＯＣＫＤＲＩＬＬＬｉｕＳｈｉｘｕｎ（ＣｏｌｌｅｇｅｏｆＭｅｃｈａｎｉｃａｌａｎｄＥｌｅｃｔｒｉｃａｌＥｎｇｉｎｅｅｒｉｎｇ，ＣｅｎｔｒａｌＳｏｕｔｈＵｎ...

关键词： hydraulic accumulator diaphragm service life stretching ratio parameter design,motion analvsis

Microstructure and formation mechanism of twins of laths of austenite with high nitrogen

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Science china(Technological Sciences) 2007年第6期50卷 755-764页

作者： WU CuiLan1,2 & LUO ChengPing2 1 Center for High Resolution Electron Microscopy, college of Materials Science and engineering, Hunan University, Changsha 410082, china 2 college of mechanical engineering, South china University of Technology, Guangzhou 510641, china 1. Center for High Resolution Electron Microscopy College of Materials Science and Engineering Hunan University Changsha 410082 China 2. college of mechanical engineering South China University of Technology Guangzhou 510641 China

The microstructure of composite diffusion layer of the nitrided and chromized 0.2% carbon steel is investigated using TEM and EDS. It is found that laths of austenite with high nitrogen (γ N) precipitate from α-ferrite matrix in the deeper zone of the diffusion layer. These γ N laths are all twins, with their {111} twinning planes parallel to the lath axis, thus forming a characteristic "back-to-back" morphology. There are two types of γN lath. The first is a genuinely {111} twin, and γ N and α keep the accurate K-S relationship, and each γ N and α form a sharp and smooth γ N/α inter- face of {335}γN//{341}α, namely habit plane {335}fcc. The second is a pseudo-twin, with micro-twins {111} or faults formed within the two twin components. Localized lattice deformation (relaxation) seems to have occurred at the interfaces of the second type of γ N due to the formation of micro-twins or faults within the twin components. These micro-twins or faults make the orientation relationship (OR) between each of the γN and the α-matrix deviate from the accurate K-S OR, and the OR between two γ N twin components deviate from the genuine {111} twin relation- ship. In addition, the γ N/α interface of the second type of γ N is not as sharp or smooth as that of the first one.

关键词： austenite containing nitrogen, twins, steel 20, nitriding, composite chromizing

Kinetics analysis of volume phase transition of intelligent neutral thermo-sensitive hydrogels

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Science china(Physics,Mechanics & Astronomy) 2008年第5期51卷 532-540页

作者： WANG XiaoGui1 & LI YiQuan2 1 college of mechanical engineering,Zhejiang University of Technology,Hangzhou 310032,china 2 School of mechanical & Electronic engineering,Changchun University of Science and Technology,Changchun 130022,china 1. college of mechanical engineering Zhejiang University of Technology Hangzhou 310032 China 2. School of mechanical & Electronic engineering Changchun University of Science and Technology Changchun 130022 China

In this work,utilizing the first law of thermodynamics and the Flory mean-field theory,the kinetic deformation studies concerning the volume phase transition of the neutral thermo-sensitive hydrogels were performed *** hydrogel was assumed as a biphasic mixture medium in the framework of the continuum mixture *** the energy conservation of the thermodynamics system of the hydrogel,the governing equations for the kinetics of the nonlinear large deforma-tion were *** explicit analytical expressions of the effective stress tensor and the chemical potential of the fluid of the thermo-sensitive hydrogel PNIPA were also obtained from the Helmholtz free energy,which can model the steady-static volume phase transition quantitatively.

关键词： thermo-sensitive hydrogel volume phase transition effective stress energy conservation

Nanostructured Sulfide Composite Coating Prepared by Atmospheric Plasma Spraying

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材料工程 2006年第Z1期34卷 281-284页

作者： GUAN Yao-hui~1,XU Yang~1,ZHENG Zhong-yu~2,TONG Xiao-hui~2(1 engineering college of china Agricultural University,Beijing 100083,china 2 Beijing Research Institute of mechanical & electrical Technology,Beijing 100083,china) engineering college China Agricultural University Beijing 100083 China Beijing Research Institute of mechanical and electrical Technology Beijing 100083 China

Nanostructured FeS-SiC coating was deposited by atmospheric plasma spraying（APS）.The microstructure and phase composition of the coating were characterized with SEM and XRD,*** addition,the size distribution of the reconstituted powders and the porosity of the coating have been *** was found that the reconstitiuted powers with sizes in the range of 20 to 80 μm had excellent flowability and were suitable for plasma spraying *** as-sprayed FeS-SiC composite coating exhibited a bimodal distribution with small grains（30～80nm） and large grains（100～200nm）.The coating was mainly composed of FeS and SiC,a small quantity of Fe1-xS and oxide were also *** porosity of the coating was approximately 19%.

关键词： plasma spraying nanostructured FeS-SiC composite coating