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Preparation of Nickel Materials with Fractal Structure

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Journal of Materials Science & Technology 2003年第3期19卷 229-231页

作者： Ruichun WANG, Jingdong GUO Benlian ZHOUshenyang national {2. for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, shenyang 110016, china Lab. for Mat. Sci. Inst. of Metal Res. Chinese Acad. of Sci. Shenyang 110016 China

A way of manufacturing nickel material with fractal structure has been studied. Some algae with natural fractal structure were used as the basic substrates. The nickel was coated on the substrates by both electroless deposition and electrodeposition. After elimination of the foundational algae by erosion, dissolution etc, the pure nickel materials with fractal structure were obtained. At last, the specific surface area was analyzed by BET analyses and the fractal dimension of the nickel material was calculated by means of box-counting technique. The comparison of fractal dimension between Ni structure and natural algae was also given.

关键词： Fractal Nickel Algae Box counting

Comparative study of the effect of Cu_2. and MoO_3 on flame retardance and smoke emission of PVC by Cone and TGA

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Chinese Science Bulletin 1998年第13期43卷 1090-1094页

作者： LI Bin\+1 and WANG Jianqi\+2.1. Department of Chemistry, Northeast Forestry University, Harbin 150040, china 2. national {2. of Flame Retardant Materials, Beijing Institute of Technology, Beijing, 100081, china Department of Chemistry Northeast Forestry University Harbin China national laboratory of Flame Retardant Materials Beijing Institute of Technology Beijing China

Cuprous and molybdic oxides exhibit extremely effectiveness in smoke suppression for PVC. However, few are the data reported concerning flame retardance and smoke emission of PVC taken from Cone calorimetry relative to the conventional thermal analysis technique. Abundant data from Cone calorimetry have been acquired. Data analysis was achieved through the study of MLR, HRR, SEA tested at irradiance of 2. kWm -2.. The understandable flame retardance of PVC/Cu\-2. and PVC/MoO\-3 relative to pure PVC has been rationalized by their lowered heat release rates and enhanced char residues. The difference in smoke reduction between these two oxides consists in the time scale. As clearly seen under air atmosphere both oxides exert themselves to the afterglow which has been recognized as a dangerous source, in particular in the full_scale fire situation.

关键词： cone calorimetry poly(vinyl chloride) flame retardation smoke emission cuprous oxide molybdic oxide.

Influence of Hot Rolling Conditions on the Mechanical Properties of Hot Rolled TRIP Steel

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Journal of Wuhan University of Technology(Materials Science) 2008年第1期23卷 74-79页

作者：李壮 WU Di Department of Materials Engineering Shenyang Institute of Aeronautical Engineering Shenyang 110034 China The State Key laboratory of Rolling and Automation Northeastern University Shenyang 110004 China

Influence of hot rolling conditions on the mechanical properties of hot rolled TRIP steel was investigated. Thermomechanical control processing （TMCP） was conducted by using a laboratory hot rolling mill, in which three different kinds of finish rolling temperatures were applied. The results show that polygonal ferrite, granular bainite and larger amount of stabilized retained austenite can be obtained by controlled rolling processes. The finer ferrite grain size is produced through the deformation induced transformation during deformation rather than after deformation, which affects the mechanical properties of hot rolled TRIP steel. Mechanical properties increase with decreasing finish rolling temperature due to the stabilization of retained austenite. Ultimate tensile strength （UTS）, total elongation （TEL） and the product of ultimate tensile strength and total elongation （UTS×TEL） reaches optimal values （791 MPa, 36% and 2. 476 MPa%, respectively） when the specimen was hot rolled for 50% reduction at finish rolling temperature of 700 ℃.

关键词： hot rolling conditions retained austenite hot rolled TRIP steels mechanical properties

Fabrication of atomically smooth SrRuO_3 thin films by laser molecular beam epitaxy

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Science china(Physics,Mechanics & Astronomy) 2008年第7期51卷 745-749页

作者： LIU GuoZhen1, HE Meng1, JIN KuiJuan1, YANG GuoZhen1, Lü HuiBin1, ZHAO Kun2. ZHENG ShiJian3 & MA XiuLiang3 1 Beijing national laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100080, {2. 2.Department of Mathematics and Physics, {2. University of Petroleum, Beijing 102.49, {2. 3 shenyang national laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, shenyang 110016, {2. 1. Beijing national laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100080 China 2. Department of Mathematics and Physics China University of Petroleum Beijing 102249 China 3. shenyang national {2. for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

High-quality SrRuO3 (SRO) thin films and SrTiO3/SRO bilayer were grown epitaxially on SrTiO3 (STO)(001) substrates by laser molecular beam epitaxy. The results of in situ observation of reflection high-energy electron diffraction and ex situ X-ray diffraction θ -2. scan indicate that the SRO thin films have good crystallinity. The measurements of atomic force microscopy and scan tunneling microscopy reveal that the surface of the SRO thin film is atomically smooth. The resistivity of the SRO thin film is 300 μΩ·cm at room temperature. Furthermore, the transmission electron microscopy study shows that the interfaces of STO/SRO and SRO/STO are very clear and no interfacial reaction layer was observed. The experimental results show that the SRO thin film is an excellent electrode material for devices based on perovskite oxide materials.

关键词： SrRuO3 thin film laser molecular beam epitaxy surface morphology

First-Principles Study of the Polar TiC/Ti Interface

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Journal of Materials Science & Technology 2003年第6期19卷 540-544页

作者： Limin LIU, Shaoqing WANG and Hengqiang YEshenyang national {2. for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, shenyang 110016, china Lab. for Mat. Sci. Inst. of Metal Res. Chinese Acad. of Sci. Shenyang 110016 China

The interface structure, work of adhesion, and bonding character of the polar TiC/Ti interface have been examined by the first-principles density functional plane-wave pseudopotential calculations. Both Ti- and C-terminated interfaces including six different interface structures were calculated, which present quite different features. For the Ti-terminated interface, the interfacial Ti-Ti bond has a strong metallic and weak covalent character; while for the C-terminated interface, the interfacial bond is a strong polar covalent interaction between the Ti-3d and C-2. orbital. The work of adhesion of C-terminated interface is nearly 9 J/m2.stronger than that of the Ti-terminated. It is found that each termination has relatively large work of adhesion, which is consistent with other polar interfaces.

关键词： First-principles Metal/ceramic interface Adhesion Carbides

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 Key laboratory of Robotics,{2. Institute of Automation,Chinese Academy of Sciences,{2. 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

316L Austenite Stainless Steels Strengthened by Means of Nano-scale Twins

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Journal of Materials Science & Technology 2010年第4期26卷 289-292页

作者： G.Z. Liu, N.R. Tao and K. Lu shenyang national {2. for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, shenyang 110016, china [a] shenyang national {2. for Materials Science Institute of Metal Research Chinese Academy of Sciences shenyang 110016 china

By means of dynamic plastic deformation （DPD） followed by thermal annealing, a mixed structure of micro-sized austenite grains embedded with nano-scale twin bundles （of about 2.% in volume） has been synthesized in a 316L stainless steel （SS）. Such a 316L SS sample exhibits a tensile strength as high as 1001 MPa and an elongation-to-failure of about 2.%. The much elevated strength originates from the presence of a considerable number of strengthening nano-twin bundles, while the ductility from the recrystallized grains. The superior strength-ductility combination achieved in the nano-twins-strengthened austenite steel demonstrates a novel approach for optimizing the mechanical properties in engineering materials.

关键词： Nano-scale twins Strength-ductility combination Dynamic plastic deformation (DPD) Stainless steels

An omnidirectional mobile robot

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Science china(Information Sciences) 2011年第12期54卷 2651-2658页

作者： YE ChangLong 1,2., MA ShuGen 2.3 & HUI Li 1 1 School of Mechatronics Engineering, shenyang Aerospace University, shenyang 110136, {2. 2.State Robotics laboratory, shenyang Institute of Automation, shenyang 110016, {2. 3 Department of Robotics, Ritsumeikan University, Kusatsu 52.-8577, Japan 1. School of Mechatronics Engineering Shenyang Aerospace University Shenyang 110136 China2. State Robotics Laboratory Shenyang Institute of Automation Shenyang 110016 China3. Department of Robotics Ritsumeikan University Kusatsu 525-8577 Japan

A novel omnidirectional wheeled mobile robot, mainly composed of three special wheeled structures-MY wheel, is developed in this paper. Based on the movement principle of sphere, the sphere of the special wheel is divided into contact part and non-contact part. The function of the omnidirectional wheel is realized utilizing the mutual complementarities of the two parts of the sphere. The passive rotational axes of two parts of the sphere are in staggered arrangement to each other at an angle of 45 degrees to realize continuous contact with the ground. At the same time, this structure also improves the strength of omnidirectional wheel. It is verified by the kinematic analysis and simulation of the wheeled mobile mechanism that the mechanism can achieve the omnidirectional movement. It is also proved by the movement experiment of the mobile robot that the omnidirectional mechanism can not only achieve the omnidirectional movements but also step over obstacles.

关键词： omnidirectional mobile robot mechanism design kinematics

Deformation Uniformity of Cold-Rolled Q2.5 Steel Rebar by FEM in Bending and Rolling Processes

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Journal of Iron and Steel Research International 2012年第8期19卷 37-42页

作者： SUI Feng-li1, CHEN Qi-wei1, ZHU Guo-hui1, LIU Bao-dong2.(1. Anhui Key laboratory of Materials and Processing, School of Materials Science and Engineering, Anhui University of Technology, Maanshan 2.3002. Anhui, china 2. Dongyang Steel Making Co Ltd, {2. 11002., Liaoning, china) [a] Anhui Key laboratory of Materials and Processing School of Materials Science and Engineering Anhui University of Technology Maanshan 243002 Anhui China [b] Dongyang Steel Making Co Ltd Shenyang 110026 Liaoning China

An analytic model based on ANSYS/LS-DYNA has been developed on the cold rolling process for Q2.5 steel rebar with 12.mm in diameter. The elastic-plastic finite element method (FEM) and the cold deformation resistance model of Q2.5 steel were adopted in this model. Deformation uniformity of the final product has been analyzed using this model. The results indicate that the uniformity of the final product is obtained only as the centerline of the bending rolls is vertical to the centerline of the driven roll and parallel to the centerline of the drive roll in the whole rolling process. Besides, the number of the bending rolls must even realize the continuous bending and reverse bending process. Also, the number of the bending rolls must match the deformation degree of the workpiece in the cold rolling process. The validity of this finite element model was verified by the size and distribution of grains from the billet to the rebar in a practical cold rolling process.

关键词： deformation uniformity Q2.5 steel rebar finite element method cold rolling mechanical descaling