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Micro water dissolution machining principle and its application in ultra-precision processing of KDP optical crystal

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Science China(Technological Sciences) 2015年第11期58卷 1877-1883页

作者： GAO Hang WANG Xu TENG XiaoJi guo dongming Key Laboratory for Precision and Non-traditional Machining Technology of Ministry of Education Dalian University of Technology

In this paper, a micro water dissolution machining(MWDM) principle is proposed for machining potassium dihydrogen phosphate(KDP) crystal using water-in-oil micro-emulsion as an abrasive-free polishing fluid. In addition, two instances of the application of this principle to ultra-precision machining of KDP crystals are presented. Computer-controlled optical surfacing(CCOS) and diamond wire cutting(DWC) process were carried out according to the MWDM principle. In the case of the CCOS technology, it is found that the micro-waviness was removed completely by following the MWDM principle. The surface undulation decreased from 40 nm to less than 10 nm, and the surface root-mean-square(rms) roughness obviously reduced from 8.147 to 2.660 nm. In the case of the DWC process, the surface rms roughness reduced from 8.012 to 2.391 μm, and the cutting efficiency was improved. These results indicate that the MWDM principle can efficiently improve the machining quality of KDP optical crystal and has a great potential to machine water-soluble materials.

关键词：超精密加工 KDP晶体加工原理水溶解应用表面粗糙度测量原理光学表面

Explicit Correlation Model of Multi-source Constraints for Re-design Parts with Complex Curved Surface

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Chinese Journal of Mechanical Engineering 2014年第2期27卷 385-391页

作者： JIA Zhenyuan WANG Fuji WANG Yongqing guo dongming Key Laboratory for Precision and Non-traditional Machining Technology of Ministry of Education Dalian University of Technology

In precision machining of complex curved surface parts with high performance, geometry accuracy is not the only constraint, but the performance should also be met. Performance of this kind of parts is closely related to the geometrical and physical parameters, so the final actual size and shape are affected by multiple source constraints, such as geometry, physics, and performance. These parts are rather difficult to be manufactured and new manufacturing method according to performance requirement is urgently needed. Based on performance and manufacturing requirements for complex curved surface parts, a new classification method is proposed, which divided the complex curved surface parts into two categories： surface re-design complex curved surface parts with multi-source constraints（PRCS） and surface unique complex curved surface parts with pure geometric constraints（PUCS）. A correlation model is constructed between the performance and multi-source constraints for PRCS, which reveals the correlation between the performance and multi-source constraints. A re-design method is also developed. Through solving the correlation model of the typical paws performance-associated surface, the mapping relation between the performance-associated surface and the related removal amount is obtained. The explicit correlation model and the method for the corresponding related removal amount of the performance-associated surface are built based on the classification of surface re-design complex curved surface parts with multi-source constraints. Research results have been used in the actual processing of the typical parts such as radome, common bottom components, nozzle, et al., which shows improved efficiency and accuracy of the precision machining for the surface re-design parts with complex curved surface.

关键词： multi-source constraints surface re-design performance associated surface explicit correlation model

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

Effects of Chloride Ion on the Texture of Copper and Cu-ZrB_(2) Coatings Electrodeposited from Copper Nitrate Solution in Different Plating Modes

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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

Failure mechanism and control technology of water-immersed roadway in high-stress and soft rock in a deep mine

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International Journal of Mining Science and Technology 2017年第2期27卷 245-252页

作者： Yang Renshu Li Yongliang guo dongming Yao Lan Yang Tongmao Li Taotao School of Mechanics and Architecture Engineering China University of Mining and TechnologyBeijing 100083China State Key Laboratory for Geomechanics and Deep Underground Engineering Beijing 100083China Faculty of Resources and Safety Engineering China University of Mining and TechnologyBeijing 100083China

Aiming at soft rock ground support issues under conditions of high stress and long-term water immersion, the ground failure mechanism is revealed by taking the deep-water sumps of Jiulong Mine as the engineering background and employing field investigation, tests of rock structure, mechanical properties and mineral composition. The main factors leading to the surrounding rock failure include the high and complex stress state of the water sumps, high-clay content and water-weakened rock, and the unreasonable support design. In this paper, the broken and fractured rock mass near roadway opening is considered as ground small-structure, and deep stable rock mass as ground large-structure. A support technology focusing on cutting off the water, strengthening the small structure of the rock and transferring the large structure of the rock is proposed. The proposed support technology of interconnecting the large and small structures, based on high-strength bolts, high-stiffness shotcrete layer plugging water,strengthening the small structure with deep-hole grouting and shallow-hole grouting, highpretensioned cables tensioned twice to make the large and small structures bearing the pressure evenly,channel-steel and high-pretensioned cables are used to control floor heave. The numerical simulation and field test show that this support system can control the rock deformation of the water sumps and provide technical support to similar roadway support designs.

关键词：巷道支护设计控制技术破坏机理高应力软岩浸水结构试验深井注浆加固

Subsurface Damage in Scratch Testing of Potassium Dihydrogen Phosphate Crystal

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Chinese Journal of Mechanical Engineering 2009年第1期22卷 15-20页

作者： WANG Ben WU Dongjiang GAO Hang KANG Renke guo dongming Key Laboratory for Precision and Non-traditional Machining Technology of Ministry of Education Dalian University of Technology Dalian 116024 China

Potassium dihydrogen phosphate （KDP） is an important electro-optic crystal, often used for frequency conversion and Pockels cells in large aperture laser systems. To investigate the influence of anisotropy to the depth of subsurface damage and the profiles of cracks in subsurface of KDP crystal, an experimental study was made to obtain the form of subsurface damage produced by scratches on KDP crystal in [100], [120] and [110] crystal directions on （001） crystal plane. The results indicated that there were great differences between depth and crack shape in different directions. For many slip planes in KDP, the plastic deformation and cracks generated under pressure in the subsurface were complex. Fluctuations of subsurface damage depth at transition point were attributed to the deformation of the surface which consumed more energy when the surface deformation changed from the mixed region of brittle and plastic to the complete brittle region along the scratch. Also, the process of subsurface damage from shallow to deep, from dislocation to big crack in KDP crystal with the increase of radial force and etch pit on different crystal plane were obtained. Because crystallographic orientation and processing orientation was different, etching pits on （100） crystal plane were quadrilateral while on （110） plane and （120） plane were trapezoidal and triangular, respectively.

关键词： potassium dihydrogen phosphate （KDP） crystal scratch subsurface damage

Dynamic caustics test of blast load impact on neighboring different cross-section roadways

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International Journal of Mining Science and Technology 2016年第5期26卷 803-808页

作者： guo dongming Zhou Baowei Liu Kang Yang Renshu Yan Pengyang School of Mechanics and Architecture Engineering China University of Mining ＆ Technology Beijing 100083 China State Key Laboratory for Geomechnics ＆Deep Underground Engineering Beijing 100083 China

Using digital laser dynamic caustics experimental system and conducting simulation experiment researched the influence rule of blasting excavation of a new roadway on neighboring existed different cross-section roadways. The experimental results show that the influence of blast load on adjacent roadway has a good relationship with the cross-section of roadway. The expansion distance of precrack existed in circular, arch-wall, rectangular roadway is respectively 1.76, 1.61 and 0 cm under blast load.At the same time, the direct-blast side of rectangular roadway has more obvious damage compared with circular and arch-wall roadway. It explains that plane reflects more stress wave than arc, so that it exerts more tensile failure in the direct-blast side, which leads to less stress wave diffracting to the precrack in the back-blast side. When the precrack extends, higher value dynamic stress intensity factor in circular roadway works longer than that of arch-wall roadway. Indirectly, it explains that plane's weakening function on stress wave is significantly stronger than arc. Stress wave brings about self-evident influence on the upper and bottom endpoints of the rectangular roadway, and it respectively extends 1.03, 2.06 cm along the line link direction of the center of the blasthole and the upper and bottom endpoints on the right wall.

关键词： Dynamic caustics Blast load Different cross-section roadways Precrack Dynamic stress intensity factor

半导体基片超精密磨削技术的研究现状与发展趋势

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机械工程学报 2023年第19期59卷 299-329页

作者：郭东明康仁科大连理工大学高性能精密制造全国重点实验室大连116024

单晶硅、碳化硅、氧化镓、氮化镓等半导体基片广泛应用于集成电路、功率器件和微传感器等半导体器件的制造。超精密磨削是半导体基片平整化加工和背面减薄加工的核心工艺技术,对半导体器件的加工效率及加工质量具有重要的影响。为了满... 详细信息

单晶硅、碳化硅、氧化镓、氮化镓等半导体基片广泛应用于集成电路、功率器件和微传感器等半导体器件的制造。超精密磨削是半导体基片平整化加工和背面减薄加工的核心工艺技术,对半导体器件的加工效率及加工质量具有重要的影响。为了满足半导体器件的使用性能,半导体材料的种类逐渐增多,半导体基片的加工要求不断提高,对半导体基片超精密磨削技术不断提出新的挑战。为了实现半导体基片的高效率高质量磨削加工,需要对半导体基片超精密磨削理论、工艺、工具和装备全面深入的理解。围绕半导体基片超精密磨削加工的表面材料去除机理、表面质量及控制方法、高效低损伤磨削工艺和超精密磨削装备的国内外研究现状进行了系统的论述与总结,分析了目前半导体基片超精密磨削技术面临的难题及未来的发展趋势,为后续半导体基片超精密磨削技术的研究提供指导。

关键词：半导体基片磨削机理工艺工具磨床