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热处理对快淬贮氢合金组织和电化学性能的影响

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稀土 2004年第1期25卷 5-8页

作者：李全安陈云贵涂铭旌河南科技大学材料科学与工程学院河南洛阳471003 四川大学金属材料系四川成都610065

通过XRD、SEM分析和电化学实验,研究了热处理对快淬贮氢合金组织和电化学性能的影响。研究表明,400℃热处理对快淬合金晶粒变化不明显,900℃热处理后合金晶粒明显长大,1100℃热处理使合金部分熔化,随后发生了平衡凝固;900℃热处理后,单... 详细信息

通过XRD、SEM分析和电化学实验,研究了热处理对快淬贮氢合金组织和电化学性能的影响。研究表明,400℃热处理对快淬合金晶粒变化不明显,900℃热处理后合金晶粒明显长大,1100℃热处理使合金部分熔化,随后发生了平衡凝固;900℃热处理后,单胞体积和放电容量均达到最大值,但充放电循环稳定性最差,400℃和1100℃热处理后,放电容量稍有降低,但充放电循环稳定性较好。

关键词：稀土贮氢合金快淬电化学性能金属氢化物 Ni-MH电池

Effect of rare-earth element Sm on the corrosion behavior of Mg-6Al-1.2Y-0.9Nd alloy

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Rare Metals 2010年第6期29卷 557-560页

作者： LI Quan’an,LI Xiaofeng,ZHANG Qing,and CHEN Jun school of materials science and engineering,henan university of science and technology,luoyang 471003,china school of materials science and engineering Henan University of Science and Technology Luoyang China

The effect of Sm（0 wt.%-2 wt.%） addition on the corrosion behavior of Mg-6Al-1.2Y-0.9Nd alloy in 3.5 wt.% NaCl solution has been studied by static corrosion tests,corrosion morphology observation,corrosion scale and microstructure *** results show that,with the increasing of Sm content,the corrosion rate of the alloy decreases at first,then increases and reaches the valley at 0.5 wt.% *** reason is that the proper content of Sm addition can refine the precipitates and make the component and microstructure uniform,and therefore,it remarkably improves the corrosion resistance of the alloy.

关键词： magnesium alloys samarium corrosion behavior microstructure

Optimization of thermomechanical processes in Cu-Cr-Zr lead frame alloy using neural networks and genetic algorithms

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science china(Technological sciences) 2005年第5期48卷 510-520页

作者： SU Juanhua1,2, LIU Ping2, DONG Qiming2 & LI Hejun1 1. College of materials science and engineering, Northwestern Polytechnical university, Xi’an 710072, china 2. College of materials science and engineering, henan university of science and technology, luoyang 471003, china 1. College of materials science and engineering Northwestern Polytechnical University 710072 Xi’an China 2. College of materials science and engineering Henan University of Science and Technology 471003 Luoyang China

The thermomechanical treatment process is effective in enhancing the properties of the lead frame copper alloy. In this study, an optimal pattern of the thermomechanical processes for Cu-Cr-Zr was investegated using an intelligent control technique consisting of neural networks and genetic algorithms. The input parameters of the artificial neural network (ANN) are the reduction ratio of cold rolling, aging temperature and aging time. The outputs of the ANN model are the two most important properties of hardness and conductivity. Based on the successfully trained ANN model, genetic algorithms (GA) are used to optimize the input parameters of the model and select perfect combinations of thermomechanical processing parameters and properties. The good generalization performance and optimized results of the integrated model are achieved.

关键词： Cu-Cr-Zr alloy, thermomechanical processing optimization, artificial neural network, genetic algorithms.

Introduction to school of Environmental science and engineering of North china Electric Power university

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Electricity 2010年第2期21卷 50-51页

作者： Zhao Yi, Ma Shuangchen school of Environmental science and engineering, North china Electric Power university school of Environmental science and engineering North China Electric Power University

Along with the fast development of national economy, environmental issues have become more and more prominent. china has promulgated a series of policies of energy-saving and emission-reduction to

关键词： school Introduction to school of Environmental science and engineering of North china Electric Power university

Dry Friction Characteristics of Ti-6Al-4V Alloy under High Sliding Velocity

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Journal of Wuhan university of technology(materials science) 2007年第4期22卷 582-585页

作者：邱明 school of Mechatronic engineering Henan University of Science and Technology Theory of Lubrication and Bearing Institute Xi'an Jiaotong UniversityXi'an 710049China

Tribological behaviours of Ti-6Al-4V alloy pins sliding against GCr15 steel discs over a range of contact pressures （0.33-1.33 MPa） and sliding velocities （30-70 m/s） were investigated using a pin-on-disc tribometer under unlubricated conditions. The wear mechanisms and the wear transition were analyzed based on examinations of worn surfaces using SEM, EDS and XRD. When the velocity increases, the friction coefficient and the wear rate of the Ti-6Al-4V alloy show typical transition features, namely, the critical values of sliding velocities for 0.33 and 0.67 MPa are 60 and 40 m/s, respectively. The experimental results reveal that the tribological behaviours of Ti-6Al-4V alloys are controlled by the thermal-mechanical effects, which connects with the friction heat and hard particles of the pairs. A tribolayer containing mainly Ti oxides and V oxides is formed on the worn surface of Ti-6Al-4V alloy.

关键词： Ti alloy dry sliding friction behavior contact temperature wear mechanism

Effect of Stoichiometry on Properties of Rare-Earth-Based Hydrogen Storage Alloy for Nickel-Metal Hydride Secondary Battery

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Journal of materials science & technology 2003年第1期19卷 90-92页

作者： Quan’an LIschool of materials science and engineering, henan university of science and technology, luoyang 471003, chinaYungui CHEN and Mingjing TUDepartment of Metal materials, Sichuan university, Chengdu 610065, china henan Univ Sci & Technol Sch Mat Sci & Engn Luoyang 471003 Peoples R China Sichuan Univ Dept Met Mat Chengdu 610065 Peoples R China

Effect of stoichiometry on microstructures, electrochemical properties and PCT characteristics of the alloys MI（Ni0.71Co0.15-Al0.06Mn0.08）x （MI=Lanthanum-rich Michmetal, x=4.6;.2） have been investigated. The lattice constants a, c, and cellvolumes of non-stoichiometric alloys are bigger than those of the stoichiometric alloy. With the increasing stoichiometry x,the value of a decreases, and the value of c and cell volume increases except for those of the stoichiometric alloy; the plateaupressure of PCT curve, discharge capacity and cycling stability all increase. The alloy with x=5.2 shows the highest dischargecapacity and the best cycling stability among the studied alloys.

关键词： Hydrogen storage alloy Metal hydride electrode Rare earth Electrochemical property Stoichiometry

Preparation of semi-solid AlSi7Mg alloy slurry with big capability

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Rare Metals 2010年第6期29卷 642-645页

作者： LI Sha and MAO Weimin school of materials science and engineering,university of science and technology Beijing,Beijing 100083,china school of materials science and engineering University of Science and Technology Beijing Beijing China

Semi-solid AlSi7Mg alloy slurry was prepared by low superheat pouring and weak traveling-wave electromagnetic *** effects of pouring temperature and stirring power on the microstructure of AlSi7Mg alloy slurry were *** results show that the semi-solid AlSi7Mg alloy slurry of 5 kg can be *** new technology can save energy and make the pouring process *** the pouring temperature is decreased at a stirring power of 0.41 kW,the shape of primary α-Al grains gradually changes from dendritic-like to *** the alloy melt is poured at the temperature（630°C） with a certain superheat,the pouring process becomes easier,and the spherical microstructure of AlSi7Mg alloy slurry can be prepared by the weak traveling-wave electromagnetic *** the pouring temperature is 630°C,increasing the stirring power appropriately can result in better spherical primary α-Al grains,but if the stirring power is increased to a certain value（1.72 kW）,the shape of primary α-Al grains does not obviously improve when the stirring power is continually increased.

关键词： aluminum alloys metal forming semisolid slurry electromagnetic stirring microstructure

Weak martingale Hardy spaces and weak atomic decompositions

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science china Mathematics 2006年第7期49卷 912-921页

作者： HOU Youliang & REN Yanbo school of Mathematics and Statistics, Wuhan university, Wuhan 430072, china Department of Mathematics & Physics, henan university of science and technology, luoyang 471003, china 1. school of Mathematics and Statistics Wuhan University Wuhan 430072 China 2. Department of Mathematics & Physics Henan University of Science and Technology Luoyang 471003 China

In this paper we define some weak martingale Hardy spaces and three kinds of weak atoms. They are the counterparts of martingale Hardy spaces and atoms in the classical martingale Hp-theory. And then three atomic decomposition theorems for martingales in weak martingale Hardy spaces are proved. With the help of the weak atomic decompositions of martingale, a sufficient condition for a sublinear operator defined on the weak martingale Hardy spaces to be bounded is given. Using the sufficient condition, we obtain a series of martingale inequalities with respect to the weak Lp-norm, the inequalities of weak (p ,p)-type and some continuous imbedding relationships between various weak martingale Hardy spaces. These inequalities are the weak versions of the basic inequalities in the classical martingale Hp-theory.

关键词： martingale, weak Hardy space, weak atom, atomic decomposition.

Effects of Sb,Sm, and Sn additions on the microstructure and mechanical properties of Mg-6Al-1.2Y-0.9Nd alloy

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Rare Metals 2009年第5期28卷 516-522页

作者： LI Kejie LI Quanan JING Xiaotian CHEN Jun ZHANG Xingyuan school of materials science and engineering Xi ＇an University of Technology Xi ＇an 710048 China school of materials science and engineering Henan Universiry of Science and Technology Luoyang 471003 China

The microstructure and mechanical properties of Mg-6Al-1.2Y-0.9Nd magnesium alloy with Sb, Sm, or Sn addition were investigated through X-ray diffraction （XRD）, optical microscopy （OM）, scanning electron microscopy （SEM）, and energy dispersive spectroscopy （EDS）. The results show that small amounts of Sb, Sm, and especially Sn can refine the grains of the alloy. High melting point Sb3Y5, Al2Sm, and Nd5Sn3 intermetallic compounds can be formed respectively when Sb, Sm, and Sn are added to the alloy. Sb and Sm can improve the tensile strength of the alloy at ambient and elevated temperatures. The tensile strength of the alloy with Sm addition is the highest at 293 and 423 K. However, the tensile strength of the alloy with Sn addition is the highest at 448 K.

关键词： magnesium alloys mechanical properties microstructure Sb Sm Sn