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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

Fabrication and Characterization of FeNiCr Matrix-TiC Composite for Polishing CVD Diamond Film

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Journal of Materials Science & Technology 2009年第3期25卷 319-324页

作者： zhuji jin Zewei Yuan Renke Kang Boxian Dong Key Laboratory for Precision and Non-Traditional Machining Technology of Ministry of Education Dalian University of Technology Dalian 116024 China

Dynamic friction polishing （DFP） is one of the most promising methods appropriate for polishing CVD diamond film with high efficiency and low cost. By this method CVD diamond film is polished through being simply pressed against a metal disc rotating at a high speed utilizing the thermochemical reaction occurring as a result of dynamic friction between them in the atmosphere. However, the relatively soft materials such as stainless steel, cast iron and nickel alloy widely used for polishing CVD diamond film are easy to wear and adhere to diamond film surface, which may further lead to low efficiency and poor polishing quality. In this paper, FeNiCr matrix-TiC composite used as grinding wheel for polishing CVD diamond film was obtained by combination of mechanical alloying （MA） and spark plasma sintering （SPS）. The process of ball milling, composition, density, hardness, high-temperature oxidation resistance and wear resistance of the sintered piece were analyzed. The results show that TiC was introduced in MA-SPS process and had good combination with FeNiCr matrix and even distribution in the matrix. The density of composite can be improved by mechanical alloying. The FeNiCr matrix-TiC composite obtained at 1273 K was found to be superior to at 1173 K sinterin8 in hardness, high-temperature oxidation resistance and wearability. These properties are more favorable than SUS304 for the preparation of high-performance grinding wheel for polishing CVD diamond film.

关键词： CVD diamond film FeNiCr matrix-TiC composite Spark plasma sintering Mechanical alloying

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

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

Prediction of the Interface Temperature Rise in Tribochemical Polishing of CVD Diamond

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Chinese Journal of Mechanical Engineering 2017年第2期30卷 310-320页

作者： Zewei YUAN Yan HE zhuji jin Peng ZHENG Qiang LI School of Mechanical Engineering Shenyang University of Technology Key Laboratory for Precision and Non-Traditional Machining Technology of Ministry of Education Dalian University of Technology

Tribochemcial polishing is one of the most efficient methods for polishing CVD （Chemical Vapor Deposition） diamond film due to the use of catalytic metal. However the difficulty to control the interface temperature during polishing process often results in low material removal because of the unstable contact process. So this research investigates the contact process in the tribo- chemical polishing of CVD diamond film and proposes a dynamic contact model for predicting the actual contact area, the actual contact pressure, and the interface tem- perature in the polishing process. This model has been verified by characterizing surface metrology of the CVD diamond with Talysurf CLI2000 3D Surface Topography and measuring the polishing temperature. The theoretical and experimental results shows that the height distribution of asperities on diamond film surface in the polishing process is well evaluated by combining the height distribution of original and polished asperities. The modeled surface asperity height distribution of diamond film agrees with the actual surface metrology in polishing process. The actual contact pressure is very large due to the small actual contact area. The predicted interface temperature can reach the catalytic reaction temperature between diamond and polishing plate when the lowest rotation speed and load are 10 000 r/min and 50 N, respectively, and diamond material is significantly removed. The model may provide effective process theory for tribochemcial polishing.

关键词： CVD diamond · Tribochemical polishing · Interface temperature · Prediction

Implementation strategies for high accuracy grinding of hydrodynamic seal ring with wavy face for reactor coolant pumps

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Science China(Technological Sciences) 2013年第10期56卷 2403-2412页

作者： FENG Guang GUO DongMing HUO FengWei jin zhuji KANG RenKe Key Laboratory for Precision and Non-Traditional Machining Technology of Ministry of Education Dalian University of Technology

Large size mechanical seals are one of the most important components used in reactor coolant ***,the hydrodynamic seal rings with wavy face are difficult to machine due to their high hardness and high form accuracy *** order to solve this difficult problem,a novel four-axis linkage grinding method using a cup wheel to process the hydrodynamic seal rings by line contact was proposed.A preliminary study indicates that the form error of the ground seal ring surface is extremely sensitive to different linkage relations of the four *** taking the center height of the cup wheel and the laws of motion along the X-axis,Z-axis,B-axis and C-axis as control variables,their effects on the principle form error of the ground surface are *** implementation strategies are proposed to reach lower principle form *** is found that the minimal principle form error is only 9.64 nm and hence its influence on the ground seal ring shape can be neglected in designing an ultra-precision grinding *** addition,the results indicate that the position accuracy of the X-axis at the microscale is acceptable no matter which implementation strategy is *** study is expected to serve as a theoretical basis for design and development of the four-axis ultra-precision grinding machine.

关键词： reactor coolant pump hydrodynamic seal ring wavy face grinding cup wheel high accuracy

Design of ultrasonic elliptical vibration cutting system for tungsten heavy alloy

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Frontiers of Mechanical Engineering 2022年第4期17卷 163-180页

作者： Sen YIN Yan BAO Yanan PAN Zhigang DONG zhuji jin Renke KANG Key Laboratory for Precision and Non-traditional Machining Technology of the Ministry of Education School of Mechanical EngineeringDalian University of TechnologyDalian 116024China

Nanoscale surface roughness of tungsten heavy alloy components is required in the nuclear industry and precision *** this study,a high-performance ultrasonic elliptical vibration cutting(UEVC)system is developed to solve the precision machining problem of tungsten heavy alloy.A new design method of stepped bending vibration horn based on Timoshenko’s theory is first proposed,and its design process is greatly *** arrangement and working principle of piezoelectric transducers on the ultrasonic vibrator using the fifth resonant mode of bending are analyzed to realize the dual-bending vibration modes.A cutting tool is installed at the end of the ultrasonic vibration unit to output the ultrasonic elliptical vibration locus,which is verified by finite element *** vibration unit can display different three-degree-of-freedom(3-DOF)UEVC characteristics by adjusting the corresponding position of the unit and workpiece.A dual-channel ultrasonic power supply is developed to excite the ultrasonic vibration unit,which makes the UEVC system present the resonant frequency of 41 kHz and the maximum amplitude of 14.2μ*** microtopography and surface roughness are obtained by the cutting experiments of tungsten heavy alloy hemispherical workpiece with the UEVC system,which validates the proposed design’s technical capability and provides optimization basis for further improving the machining quality of the curved surface components of tungsten heavy alloy.

关键词： tungsten heavy alloy ultrasonic elliptical vibration cutting Timoshenko’s theory resonant mode of bending finite element method

Advances in molecular dynamics simulation of ultra-precision machining of hard and brittle materials

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Frontiers of Mechanical Engineering 2017年第1期12卷 89-98页

作者： Xiaoguang GUO Qiang LI Tao LIU Renke KANG zhuji jin Dongming GUO Key Laboratory for Precision & Non-traditional Machining of Ministryof Education Dalian University of Technology Dalian 116024 China

Hard and brittle materials, such as silicon, SiC, and optical glasses, are widely used in aerospace, military, integrated circuit, and other fields because of their excellent physical and chemical properties. However, these materials display poor machinability because of their hard and brittle properties. Damages such as surface micro-crack and subsurface damage often occur during machining of hard and brittle materials. Ultra-precision machining is widely used in processing hard and brittle materials to obtain nanoscale machining quality. However, the theoretical mechanism underlying this method remains unclear. This paper provides a review of present research on the molecular dynamics simulation of ultra-precision machining of hard and brittle materials. The future trends in this field are also discussed.

关键词： MD simulation ultra-precision machining,hard and brittle materials machining mechanism review

A review of low-temperature plasma-assisted machining:from mechanism to application

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Frontiers of Mechanical Engineering 2023年第1期18卷 35-53页

作者： Jiyu LIU Yuheng LI Yang CHEN Yuyang ZHOU Shuaishuai WANG Zizhen YUAN zhuji jin Xin LIU Key Laboratory for Precision and Non-traditional Machining Technology of the Ministry of Education Dalian University of TechnologyDalian 116024China

Materials with high hardness,strength or plasticity have been widely used in the fields of aviation,aerospace,and military,among ***,the poor machinability of these materials leads to large cutting forces,high cutting temperatures,serious tool wear,and chip adhesion,which affect machining ***-temperature plasma contains a variety of active particles and can effectively adjust material properties,including hardness,strength,ductility,and wettability,significantly improving material *** this paper,we first discuss the mechanisms and applications of low-temperature plasma-assisted *** introducing the characteristics,classifications,and action mechanisms of the low-temperature plasma,we describe the effects of the low-temperature plasma on different machining processes of various difficult-to-cut *** low-temperature plasma can be classified as hot plasma and cold plasma according to the different equilibrium *** plasma improves material machinability via the thermal softening effect induced by the high temperature,whereas the main mechanisms of the cold plasma can be summarized as chemical reactions to reduce material hardness,the hydrophilization effect to improve surface wettability,and the Rehbinder effect to promote *** addition,hybrid machining methods combining the merits of the low-temperature plasma and other energy fields like ultrasonic vibration,liquid nitrogen,and minimum quantity lubrication are also described and ***,the promising development trends of low-temperature plasma-assisted machining are presented,which include more precise control of the heat-affected zone in hot plasma-assisted machining,cold plasma-assisted polishing of metal materials,and further investigations on the reaction mechanisms between the cold plasma and other materials.

关键词： low-temperature plasma difficult-to-cut material machinability hydrophilization effect Rehbinder effect