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Journal of Materials Science & Technology 2006年第5期22卷 643-646页

作者： dongming guo min zhang zhuji jin renke kang Key laboratory for Precision ＆ Non-traditional Machining of ministry of Education Dalian University of TechnologyDalian 116023 China

For the first time, the texture of copper and Cu-ZrB2 coatings produced from copper nitrate solution was studied. Chloride ion shows different effects on the deposit texture under direct current （DC） and pulse current （PC） conditions. Copper deposits are strongly 〈220〉 textured in DC plating with and without chloride ion. While in PC condition, the predominant texture shifts from 〈220〉 to 〈200〉 as the chloride ion concentration exceeds 20 mg/l. The addition of ZrB2 particles enhances the cathodic polarization of copper deposition, which improves the growth of （111） plane. However, this improvement can be eliminated by further addition of chloride ion.

关键词： Texture Chloride ion Pulse plating Coatings

Pulse Plating of Copper-ZrB_(2) Composite Coatings

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Journal of Materials Science & Technology 2006年第4期22卷 514-518页

作者： dongming guo min zhang zhuji jin renke kang Key laboratory for Precision ＆ Non-traditional Machining of ministry of Education Dalian University of Technology Dalian 116023 China

Copper-zirconium diboride （ZrB2） composite coatings were fabricated using pulse plating technique to acquire a new type of EDM （electro-discharge machining） electrode material. The effects of pulse parameters, i.e., the average current density, the frequency and the duty cycle, on the incorporation of ZrB2 particles in the copper matrix were investigated. The amount＇of codeposited ZrB2 particles had a maximum at average current density of 3 A/din2 and increased with decreasing duty cycle as well as current frequency of the pulse current used for deposition. The hardness of the coatings increased with increasing ZrB2 percentage, whereas the incorporation of ZrB2 particles had little effect on the resistivity of the composites.

关键词： Pulse plating Codeposition Composite coatings

Effect of direct current and pulse plating on the EDM performance of copper-zirconium diboride composites

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Journal of University of Science and Technology Beijing 2007年第5期14卷 464-468页

作者： dongming guo min zhang zhuji jin renke kang Key Laboratory of the ministry of Education of China for Precision ＆ Non-traditional Machining Dalian University of Technology Dalian 116024 China

Direct current and pulse plating of copper-zirconium diboride （ZrB2） composites were studied and the effects of current density （DC） and pulse duty cycle （PC） on the EDM performance of the composites were investigated. With increasing current density, the effect of grain refinement on the electro-discharge machining （EDM） performance of the composites compensates that of the decrease of ZrB2 content in the composites, which improves the spark-resistance of the material. Under the same average current density and other experiment conditions, a lower duty cycle yields better EDM performance probably because more ZrB2 particles are incorporated in the composites in this condition. However, at a still lower duty cycle （10%）, the particle agglomeration and the microcracks of the copper matrix occur, which considerably deteriorate the spark-resistance of the composites.

关键词： composites pulse plating electro-discharge machining (EDM) electrode

Microstructure studies of the grinding damage in monocrystalline silicon wafers

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Rare Metals 2007年第1期26卷 13-18页

作者： zhang Yinxia kang renke guo dongming jin zhuji Key Laboratory for Precision and Non-traditional Machining Technology of Chinese minisWy of Education Dalian University of Technology Dalian116024 China

The depth and nature of the subsurface damage in a silicon wafer will limit the performance of IC components. Damage microstructures of the silicon wafers ground by the #325, #600, and #2000 grinding wheels was analyzed. The results show that many microcracks, fractures, and dislocation rosettes appear in the surface and subsurface of the wafer ground by the #325 grinding wheel. No obvious microstructure change exists. The amorphous layer with a thickness of about 100 nm, microcracks, high density dislocations, and polycrystalline silicon are observed in the subsurface of the wafer ground by the #600 grinding wheel. For the wafer ground by the #2000 grinding wheel, an amorphous layer of about 30 nm thickness, a polycrystalline silicon layer, a few dislocations, and an elastic deformation layer exist. In general, with the decrease in grit size, the material removal mode changes from micro-fracture mode to ductile mode gradually.

关键词： silicon wafers grinding subsurface damage microstructure

Atomistic understanding of interfacial processing mechanism of silicon in water environment:A ReaxFF molecular dynamics simulation

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Frontiers of Mechanical Engineering 2021年第3期16卷 570-579页

作者： Song YUAN Xiaoguang guo Penghui LI Shuohua zhang ming LI zhuji jin renke kang dongming guo Fumin LIU Lemin zhang Key Laboratory for Precision and Non-Traditional Machining Technology of ministry of Education Dalian University of TechnologyDalian 116024China Beijing Institute of Aerospace Control Device Beijing 100854China

The interfacial wear between silicon and amorphous silica in water environment is critical in numerous ***,the understanding regarding the micro dynamic process is still unclear due to the limitations of ***,reactive force field simulations are utilized to study the interfacial process between silicon and amorphous silica in water environment,exploring the removal and damage mechanism caused by pressure,velocity,and ***,the reasons for high removal rate under high pressure and high velocity are elucidated from an atomic *** results show that the substrate is highly passivated under high humidity,and the passivation layer could alleviate the contact between the abrasive and the substrate,thus reducing the damage and *** addition to more Si-O-Si bridge bonds formed between the abrasive and the substrate,new removal pathways such as multibridge bonds and chain removal appear under high pressure,which cause higher removal rate and severer *** a higher velocity,the abrasive can induce extended tribochemical reactions and form more interfacial Si-O-Si bridge bonds,hence increasing removal *** results reveal the internal cause of the discrepancy in damage and removal rate under different conditions from an atomic level.

关键词： silicon ReaxFF molecular dynamics friction damage

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精密导电滑环表面微槽车削性能

宇航材料工艺 2015年第4期45卷 108-113页

作者：耿星郭东明金洙吉张兰芳大连理工大学精密与特种加工教育部重点实验室大连116024

采用超精密车削精密导电滑环导电环的方法,保证了精密导电滑环绝缘环与导电环的同轴度、环间距,使绝缘微槽变形量低于0.10 mm。建立了精密导电滑环的切槽模型,利用仿真分析讨论了主轴转速、进给速率、刀具前角和切削深度对微槽变形量的... 详细信息

采用超精密车削精密导电滑环导电环的方法,保证了精密导电滑环绝缘环与导电环的同轴度、环间距,使绝缘微槽变形量低于0.10 mm。建立了精密导电滑环的切槽模型,利用仿真分析讨论了主轴转速、进给速率、刀具前角和切削深度对微槽变形量的影响,并对模型进行了试验验证。结果表明:滑环微槽侧面变形量随主轴转速的增大而变大,当转速达到700 r/min时,变形量达到了0.10 mm,超出了滑环的精度要求;滑环微槽变形量随机床进给速率的增大而变大,当进给速率达到1.5 mm/min时,变形量超出了滑环的精度要求;滑环微槽变形量随着前角的增大而减小;滑环微槽变形量随切削深度的增大而变大,切削深度低于0.2 mm时,滑环变形量微乎其微。

关键词：精密导电滑环导电环超精密车削切槽模型