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Journal of Materials science & technology 2001年第5期17卷 485-489页

作者： Qingfu CHEN, Wei CAi and Liancheng ZHAO school of Materials science and {2., Harbin Institute of technology, Harbin 150001, china Harbin Inst Technol Sch Mat Sci & Engn Harbin 150001 Peoples R China

The paper studied the relationship between microstructure and shape recovery characteristics by using colored microstructure analysis under polarized light on the thermomechanical cycled CuAlNi single crystals. The two-way shape memory effect in quenched thin bar resulted from the preferential formation/extinction of martensite variant due to the internal quench stress, and the variant was formed at an angle of about 45 deg. with the tension direction ([001] of the βphase). Initial thermomechanical cycling under relatively low stress single variant stress-induced martensite was formed at an angle of 45 deg. with the tension and its morphology was a lath of parallel twins. More than one group of variants were formed after several training cycles and such variants also caused tilting of some thermally formed accommodated martensite. By overheating the trained sample containing stabilized multi-variants of stress-induced martensite, very coarse martensite structure with a strong asymmetry was produced, which caused the reverse two-way shape memory effect.

关键词： Relationship between Colored Microstructure under Polarized Light and Shape Recovery Characteristics on the Thermomechanical Cycled CuAlNi Single Crystals

Effects of Er on the microstructure and properties of AZ31 magnesium alloy prepared via the EMS process

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Rare Metals 2010年第4期29卷 339-345页

作者： MA Yutao,ZHANG Xingguo,LIU Hongbin,and MENG Linggang school of Materials science and {2.,Dalian University of technology,Dalian 11602.,china school of Materials science and {2. Dalian University of Technology Dalian China

The effects of small amounts of the rare-earth element erbium on the microstructure and the mechanical properties of AZ31 magnesium alloy via the electromagnetic stirring （EMS） process have been studied. It has been shown that AZ31-Er alloys are mainly composed of α-Mg solid solution and β-Mg17TA112.phases. When the Er content reaches 0.12.wt.%, the characteristic peaks of A12.r can be observed. The micro- structure is obviously refined and the tensile strength of the AZ31-based alloy at ambient temperature is significantly improved by contents of 0.03 wt.% Er, especially the elongation （8= 19%）. More addition of Er obviously decreases the tensile strength and elongation of the AZ31-based alloy because of the grain coarsening and the reduction of β-Mg17A112.phases.

关键词： AZ31 magnesium alloy microstructure mechanical properties erbium

Refinement of packet size in low carbon bainitic steel by special thermo-mechanical control process

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Journal of University of science and technology Beijing 2004年第3期11卷 221-224页

作者： Chengjia Shang Xuemin Wang Shanwu Yang Xinlai He Materials science and engineering {2., University of science and technology Beijing, Beijing 100083, china Mat. Sci. and Eng. Sch. Univ. of Sci. and Technol. Beijing Beijing 100083 China

The packet size of bainitic steel can be refined by a specialrelaxation-precipitation-control phase transformation (RFC) technology. When processed by RPCprocess, the low carbon bainitic steel composes of two kinds of main intermediate transformationphases. One is ultra-fine lath-like bainitic ferrite and the lath is less than 1μm in width andabout 6 μm in length; the alignment of laths forms a refined packet, and the size of packets isabout 5-7 μm in length and about 3-4μm in width. The other is acicular structure. The morphologyand distribution of these acicular structures are influenced by relaxation process, the thin andshort acicular structures cut the prior austenite grain and refine the bainitic packet size. For theoptimum relaxation time, the packet size can be refined to the finest. The mechanical propertiesare influenced by relaxation time and the 800 MPa grade low carbon bainitic steel with excellenttoughness can be obtained by RPC process.

关键词： packet size refinement bainitic steel RPC process

Fabrication and Characterization of Nano Silver Powder Prepared by Spray Pyrolysis

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Journal of Wuhan University of technology(Materials science) 2009年第6期24卷 871-874页

作者：章桥新 school of mechanical and Electronic {2. Wuhan University of Technology State Key Laboratory of Advanced technology for Materials Synthesis & Processing Wuhan University of Technology

Silver powder was fabricated by spray pyrolysis, using 2.-2.% AgNO3 solution, 336-500 mL/h flux of AgNO3 solution, 0.2.-0.32.MPa flux of carrier gas and in the 62.-82. ℃ temperature range. The effects of furnace set temperature, concentration of AgNO3 aqueous solution, flux of AgNO3 aqueous solution as well as carrier gas on the morphology and particle size distribution of silver powder, were investigated. The experimental results showed that with the high concentration of AgNO3 aqueous solution, the average grain size of silver decreased with the increasing of furnace set temperature. But the gain size distribution was not homogenous, the discontinuous grain growth occurred. With the low concentration of AgNO3 aqueous solution, the higher furnace set temperature made the nano sliver grains sintered together to grow. Nano silver powder about 100 nm was fabricated by spray pyrolysis, using 2.t% AgNO3 solutions, 336 mL/h flux of AgNO3 aqueous solution, 0.32.MPa flux of carrier gas at 72. ℃ furnace set temperature.

关键词： nano silver powder fabrication characterization spray pyrolysis

MODELING AND IMPLEMENTATION OF A DISTRIBUTED SHOP FLOOR MANAGEMENT AND CONTROL SYSTEM

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Chinese Journal of mechanical engineering 2002年第3期15卷 213-217页

作者： Liu Shiping Rao Yunqing Zhang Jie Li Peigenschool of mechanical {2. and engineering, Huazhong University of {2. and technology,Wuhan 430074, china school of mechanical {2. and engineering Huazhong University of Science and Technology Wuhan 430074

Adopting distributed control architecture is the important developmentdirection for shop floor management and control system, is also the requirement of making it agile,intelligent and concurrent. Some key problems in achieving distributed control architecture areresearched. An activity model of shop floor is presented as the requirement definition of theprototype system. The multi-agent based software architecture is constructed. How the core part inshop floor management and control system, production plan and scheduling is achieved. Thecooperation of different agents is illustrated. Finally, the implementation of the prototype systemis narrated.

关键词： Agent Shop floor management and control CIMS

Interactive graphics mechanical optimum design

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International Journal of Minerals,Metallurgy and Materials 1997年第3期11卷 54-56页

作者： WANG Guobiao (Resources engineering school, University of {2. and technology Beijing, Beijing 100083, china)

Virtually all conventional optimizations are Performed in a batch computer environment. No graphic information during the optimization process is provided. The research tactics and implementation procedure of interactivegraphics in mechanical optimum design are presented. An interactive Graphics mechanical Optimum Design Program(IGMODP) for microcomputers is developed. The example of wheeled loader' s working device optimum design usingIGMODP is carried out.

关键词： interactive graphics mechanical optimum design computer program

Thermal Insulation and Strength of Autoclaved Light Concrete

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Journal of Wuhan University of technology(Materials science) 2011年第1期26卷 132-136页

作者：杨若冲吴智深 school of Transportation Southeast University Institute of Urban engineering science & {2. Southeast University

The primary objective of this study was to develop an autoclaved light concrete （ALC） material with ultra-thermal insulation property and to investigate the relationship between its physical characteristics and mechanical properties. Through tests of dry bulk density and compressive strength, relationship of physical characteristics and mechanical properties of samples were studied, resulting in a material with ultra-thermal insulation property. Scanning electron microscope （SEM） and energy-dispersive X-ray spectroscopy （EDX） were applied to analyze the micro-morphology and elemental composition of samples. To identify the product phases, X-ray diffraction （XRD） was engaged. The test results showed that compressive strength and thermal coefficient were reduced with the increasing of aluminum powder within the mixtures. As a result the optimal thermal coefficient and compressive strength of samples were improved to 0.061 W/（m·k） and 1.2.MPa, respectively. SEM, EDX and XRD analyses showed that calcium silicate hydrate and tobermorite crystal were main resultant phases.

关键词： autoclaved light concrete ultra-thermal insulation microscopic appearance and phase analysis tobermorite crystal

Vanadium Carbide Coating Growth on Die Steel Substrate in Borax Salt Bath

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Journal of Wuhan University of technology(Materials science) 2010年第4期25卷 600-603页

作者：王洪福 school of Materials science and {2. Wuhan University of Technology school of mechanical {2. and Automation North University of China

Vanadium pentoxide, borax, boron carbide and sodium fluoride were used to grow vanadium carbide coating on die steel（Cr12. Cr12.oV） surface at 950 ℃ by TD process, which extended the life period of Cr12.and Cr12.oV as punching die. Kinetics of vanadium carbide coating growth was brought forward and verified by comparison of the mathematical model with the experimental results. The thickness of coating was illustrated by SEM. The chemical constituent of coating and remnants were tested by XRD. To increase the thickness, rare earths （FeSiRe2.） were added to the borax salt bath. The electronic probe microanalysis （EPMA） revealed that the addition of rare earths could decrease carbon concentration in the coating and increase the depth of vanadium carbide coating.

关键词： vanadium carbide coating TD process punching die rare earths

Tribological Properties of PVA-H Composites Reinforced by Nano-HA Particles

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Journal of Wuhan University of technology(Materials science) 2007年第3期22卷 490-493页

作者：吴刚 school of mechanical {2. Shanghai Jiaotong University

The friction and wear behaviors of tribological mechanical components were studied on a four-ball tester under dry conditions, and the wear mechanism was analyzed by observed worn surface using a scanning electron microscope （SEM）. It was found that the friction and wear properties were improved by the addition ofnano HA particles. The composite containing 1 wt% nano HA had the optimum friction coefficient. It is also found that the addition of nano HA increases the wear resistance of oure PVA-H and PVA-H composites.

关键词： articular cartilage composites wear friction coefficient corrosion-abrasion