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Rare Metals 2007年第S1期26卷 175-179页

作者： LIU Xujing state key laboratory of Material Surface modification by laser,ion and electronic beams,dalian university of technology,dalian 116023.china dalian Univ Technol State Key Lab Mat Surface Modificat Laser Ion & E Dalian 116023 Peoples R China

Mg alloy AZ31B was welded to Al alloy 6061 by laser welding *** welded samples were exampled by metallographic techniques using both optical and scanning microscopy in combination with energy dispersive spectroscopy microanalysis(EDS).Compared with the TIG welding joint,the mechanism of joining dissimilar metal magnesium and aluminum by laser was *** is found that magnesium is swirled by laser and the weld pool forms down toward *** microstructure at the bottom of the molten pool was *** swirl made the continuous intermetallic compounds at the interface between Mg and Al more *** intermetallic compounds still existed using this high speed welding technique and reduced the joint strength.

关键词： laser welding magnesium alloy aluminum alloy intermetallic compounds

Influence of Nitrogen Flow Rate on the Microstructure and Properties of N and Me (Me=Cr,Zr) Co-doped Diamond-like Carbon Films

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Journal of materials Science & technology 2010年第11期26卷 967-972页

作者： Zhiyun Han,Hongkai Li,Guoqiang Lin and Chuang Dong key laboratory for Material modification by laser,ion and electron beams,dalian university of technology,dalian 116085,china key laboratory for Material modification by laser Ion and Electron Beams Dalian University of Technology Dalian 116085 China

In this paper,Me （Me=Cr,Zr） and N co-doped diamond like carbon （DLC-MeN） composite films were prepared on cemented carbide substrates by pulsed bias arc ion *** effect of nitrogen flow rates on the microstructure and properties of the films were investigated by X-ray photoelectron spectroscopy （XPS）,Raman spectra,grazing incident X-ray diffraction （GIXRD）,high resolution transmission electron microscopy （HRTEM） and ***,GIXRD and HRTEM results show that the deposited films are nanocomposite films with MeN nanocrystalline phase embedded within DLC amorphous matrix,which are vital for the mechanical properties of the *** nitrogen flow rate has significant effect on the compositions and structures and hence on the hardness and elastic modulus of the films,and increasing nitrogen flow rate decreases drastically the hardness and elastic modulus of the films.

关键词： Diamond like carbon films Doping Nitrogen flow rate Arc ion plating

Influence of the low-frequency source parameters on the plasma characteristics in a dual frequency capacitively coupled plasma reactor:Two dimensional simulations

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Progress in Natural Science:materials International 2009年第6期19卷 677-684页

作者： Xiang Xu, Hao Ge, Shuai Wang, Zhongling Dai, Younian Wang , Aimin Zhu state key Lab of materials modification by electron, ion and laser beams, School of Physics and Optoelectronic technology, dalian university of technology, dalian 116023. china state key Lab of materials modification by electron Ion and Laser Beams School of Physics and Optoelectronic Technology Dalian University of Technology Dalian 116023 China

A two-dimensional (2D) fluid model is presented to study the discharge of argon in a dual frequency capacitively coupled plasma (CCP) reactor. We are interested in the influence of low-frequency (LF) source parameters such as applied voltage amplitudes and low frequencies on the plasma characteristics. In this paper, the high frequency is set to 60 MHz with voltage 50 V. The simulations were carried out for low frequencies of 1, 2 and 6 MHz with LF voltage 100 V, and for LF voltages of 60, 90 and 120 V with low frequency 2 MHz. The results of 2D distributions of electric field and ion density, the ion flux impinging on the substrate and the ion energy on the powered electrode are shown. As the low frequency increases, two sources become from uncoupling to coupling. When two sources are uncoupling, the increase in LF has little impact on the plasma characteristics, but when two sources are coupling, the increase in LF decreases the uniformities of ion density and ion flux noticeably. It is also found that with the increase in LF voltage, the uniformities in the radial direction of ion density distribution and ion flux at the powered electrode decreases significantly, and the energy of ions bombarding on the powered electrode increases significantly.

关键词： Dual frequency Capacitively coupled plasma Fluid simulation

Low-power YAG laser/arc hybrid welding of AZ-based Mg alloy

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Rare Metals 2007年第S1期26卷 67-72页

作者： HAO Xinfeng,and SONG Gang state key laboratory of materials modification,School of materials Science and Engineering,dalian university of technology,dalian 116024,china dalian Univ Technol Sch Mat Sci & Engn State Key Lab MAt Modificat Dalian 116024 Peoples R China

The results of recent researches on the weldability of laser/arc hybrid welding of AZ-based Mg alloy was *** were conducted with a low-power(500 W) Nd:YAG laser and a TIG *** synergic effects and mechanical properties of the Mg joints by laser/arc hybrid welding were investigated,and the interaction mechanism of laser to arc was also *** results show that Mg alloys can be easily welded in similar and dissimilar joints by laser/arc hybrid welding *** the arc power increasing,a higher weld depth is obtained,and the weld depths for laser and arc acting in combination(laser/arc) are two times higher than that of the total of laser and arc acting separately(laser+arc) in optimal *** tensile strength and fatigue strength of the AZ31B joints welded by laser/arc hybrid process are equivalent to that of the based ***,the laser-induced plume/plasma images captured by high speed camera were used to study the interaction between laser beam and arc.

关键词： Mg alloy laser/arc hybrid welding tensile strength fatigue strength

Deposition and Properties of CrN_x films by High Power Pulsed Unbalanced Magnetron Sputtering

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稀有金属材料与工程 2011年第S4期40卷 160-163页

作者： Mu Xiaodong,Mu Zongxin,Wang Chun,Jia Li,Zang Hirong,Liu Bingbing,Dong Chuang key laboratory of materials modification by laser,ion and electron beams (dalian university of technology),Ministry of Education,School of Physics and Optoelectronic technology,dalian university of technology,dalian 116024,china dalian Univ Technol Sch Phys & Optoelect Technol Minist Educ Key Lab Mat Modificat Laser Ion & Electron Beams Dalian 116024 Peoples R China

High-power pulsed magnetron sputtering (HPPMS) technology has drawn extensively attention for producing ultra-high dense plasma and high ionization fractions of the sputtered species,depositing dense films with high *** films were deposited on the substrates of Si(100) using high-power pulsed unbalanced magnetron sputtering (HPPUMS) technology,and the analyses of XRD and atomic force microscope (AFM) were conducted on the properties of microstructure and surface morphology of CrNx films;the friction coefficient and the adhesion between CrNx film and substrate were measured,*** was found HPPUMS discharge is able to deposit CrNx films with super comprehensive properties:higher adhesive strength between the film and substrate and lower coefficient of *** rate of CrNx films,which was tested by interferometry,was about 4.2nm/min at 0.6Pa and the pulse power density up to 6.8kW/cm2 with the pulse repetition frequency of 0.7Hz,which is about 56% of that provided by the mid-frequency magnetron sputtering discharge under the conditions of the same average power ***,clusters with a dimension of several hundred nanometers were observed on the AFM morphology probably related to high pulse current.

关键词： plasma sources plasma-based ion implantation and deposition thin film structure and morphology deposition by sputtering

A Study of AlN Films Prepared by Arc ion Plating

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Journal of materials Science & technology 2003年第1期19卷 27-29页

作者： Meidong HUANG, Chunyan LU, Bing WANG, Chao SUN, Rongfang HUANG and Lishi WENInstitute of Metal Research, Chinese Academy of Science, Shenyang 110016, chinaGuoqiang LIN and Chuang DONGstate key laboratory for materials modification by laser, ion, and electron beams, dalian university of technology, dalian 116024, china Inst. of Metal Res. Chinese Acad. of Sci. Shenyang 110016 China Lab. for Mat. modification by laser Ion. and Electron. Beams Dalian Univ. of Technol. Dalian 116024 China

Hexagonal AIN films have been obtained by arc ion plating at different negative biases. X-ray diffraction and scanningelectron microscopy results show that AIN films with smooth surfaces and (002) preferred orientation are obtainedat low biases, whereas those with coarse surfaces and (100) preferred orientation are obtained at high biases. Theformation mechanism of AIN is analyzed and the experiment results are discussed. The effect of bias on adhesionstrength has also been examined.

关键词： A1N AIP Preferential orientation Bias

Online diagnosis of electron excitation temperature in CH_4+H_2 discharge plasma at atmospheric pressure by optical emission spectra

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Science china(Physics,Mechanics & Astronomy) 2008年第12期51卷 1892-1896页

作者： CUI JinHua1, XU ZhenFeng2, ZHANG JiaLiang3↑, NIE QiuYue3, XU GenHui4 & REN LongLiang5 1 Faculty of Chemistry and Chemical Engineering, Liaoning Normal university, dalian 116021, china 2 Technique Center for Modern Education, Liaodong College, Dandong 126709, china 3.state key laboratory for materials modification by laser, ion and electron beams, dalian university of technology, dalian 116023. china 4 College of Chemical Engineering, Tianjin university, Tianjin 300072, china 5 Department of Physics, Science College, Tianjin university, Tianjin 300072, china Faculty of Chemistry and Chemical Engineering Liaoning Normal University Dalian China Technique Center for Modern Education Liaodong College Dandong China state key laboratory for materials modification by laser Ion and Electron Beams Dalian University of Technology Dalian China College of Chemical Engineering Tianjin University Tianjin China Department of Physics Science College Tianjin University Tianjin China

Methane coupling under low temperature plasmas at atmospheric pressure is a green process by use of renewable sources of energy. In this study, CH4+H2 dis- charge plasma was on-line diagnosed by optical emission spectra so as to char- acterize the discharge system and to do spade work for the optimization of the technical parameters for future commercial production of methane coupling under plasmas. The study was focused on a calculation method for the online diagnosis of the electron excitation temperature in CH4+H2 discharge plasma at atmospheric pressure. The diagnostic method is easy, efficient and fairly precise. A serious er- ror in a literature was corrected during the reasoning of its series of equations formerly used to calculate electron temperatures in plasmas.

关键词： low temperature plasma electron excitation temperature optical emission spectrum online diagnosis

Enhanced Surface Properties Induced by High Current Pulsed electron Beam (HCPEB) Treatment

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稀有金属材料与工程 2011年第S4期40卷 178-180页

作者： Hao Shengzhi1,2,Wang Huihui1,2,Li Mincai1,3,Xu Yang1,3,Dong Chuang1,3 1key laboratory of materials modification by laser,ion and electron beams,Ministry of Education,dalian university of technology,dalian 116024,china2School of Physics and Optoelectronics Engineering,dalian university of technology,dalian 116024,china3School of Material Science and Engineering,dalian university of technology,dalian 116024,china dalian Univ Technol Minist Educ Key Lab Mat Modificat Laser Ion & Electron Beams Dalian 116024 Peoples R China dalian Univ Technol Sch Phys & Optoelect Engn Dalian 116024 Peoples R China dalian Univ Technol Sch Mat Sci & Engn Dalian 116024 Peoples R China

High current pulsed electron beam (HCPEB) has been developed as a useful tool for surface treatment of *** the present work,the fundamental principle of HCPEB source was described along with the device configuration and working *** the different kinds of HCPEB surface treatment experiments conducted,the enhanced surface properties induced by HPCEB treatment were illustrated and explained with their microstructure characterization results.

关键词： high current pulsed electron beam surface treatment microstructure property

FLOW STRUCTURE AND SEDIMENT TRANSPORT WITH IMPACTS OF AQUATIC VEGETATion

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Journal of Hydrodynamics 2008年第4期20卷 461-468页

作者： LIU Cheng SHEN Yong-ming Pearl River Hydraulic Research Institute Guangzhou 510611 China state key laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116023 China state key L-aborat-ory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116023China

Aquatic vegetation plays an important role in the flow structure of open channels and thus changes the fate and the transport of sediment. This article proposes a three-dimensional turbulence model by introducing vegetation density and drag force into the control equations of water flow in the presence of vegetation. The model was used to calculate the impacts of submerged vegetation on the vertical profiles of longitudinal flow velocities, the changes of the depth-averaged flow velocities in a compound channel with emergent vegetation in the floodplain, the removal of suspended sediment from the channels by emergent vegetation, and the bed changes around and in a vegetated island. Numerical investigations show that aquatic vegetation retards flow in the vegetation zone, reduces the sediment transport capacity, and contributes to erosion on both sides of the vegetated island. Calculated results agree well with experimental results.

关键词： three-dimensional turbulence model aquatic vegetation flow structure sediment transport suspended sediment bed surface topography change