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钛合金表面椭圆微坑阵列模板电解加工试验研究

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电加工与模具 2024年第2期 31-37页

作者：严政王天明李寒松房晓龙南京航空航天大学机电学院江苏南京210016 北京卫星制造厂有限公司北京100094

针对离子推进器织构化流道高效精密加工需求,开展TC4钛合金表面椭圆形微坑阵列模板电解加工试验研究。通过电场有限元仿真,发现随着加工进行,微坑逐渐由矩形变为椭圆并最终变为近似圆形,而且微坑在椭圆短轴方向上增量要大于长轴方向。... 详细信息

针对离子推进器织构化流道高效精密加工需求,开展TC4钛合金表面椭圆形微坑阵列模板电解加工试验研究。通过电场有限元仿真,发现随着加工进行,微坑逐渐由矩形变为椭圆并最终变为近似圆形,而且微坑在椭圆短轴方向上增量要大于长轴方向。通过设计一种辅助支撑压紧装置以抑制非加工表面杂散腐蚀,研究了加工时间、占空比对微坑尺寸的影响。研究表明,在加工电压30 V、频率2 kHz、时间60 s、占空比8%的优选参数下,可以实现椭圆形微坑阵列的高效高一致性加工,得到的平均深度为98.04μm,长轴和短轴平均宽度分别为198.25μm和186.84μm。

关键词：模板电解加工钛合金阵列结构椭圆形微坑杂散腐蚀

Experimental investigation of rotary sinking electrochemical discharge milling with high-conductivity salt solution and non-pulsed direct current

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Chinese Journal of Aeronautics 2023年第2期36卷 388-401页

作者： Xiaokang YUE Yuehong MA Ningsong QU hansong li College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China

Electrochemical milling is a modified technique of traditional electrochemical machining(ECM)that can be used to manufacture some helicopter transmission system *** use of rotary tools and an inner-jet electrolyte supply pattern can greatly improve the material removal rate(MRR)in a single ***,the feed speed is generally limited to minimize the tool *** increase the MRR,electrical discharge machining(EDM)is introduced into the electrochemical milling *** tool rotation is employed to interrupt the discharge and the high-conductivity salt solution and non-pulsed direct current power supply are also adopted to increase ECM,eventually,a new machining method is proposed,which can be called rotary sinking electrochemical discharge milling(RSECD milling).The mechanism of it is explored in this study by analyzing the machined current,MRR,surface morphology,and tool wear at different applied voltages and feed ***,the RSECD milling using the tool with a larger diameter is also conducted to further verify the *** particular,the MRR can be increased by 742.5%when using the tool with a diameter of 20 mm at the applied voltage of 20 V.

关键词： Electrochemical discharge machining Electrochemical milling High-conductivity salt solution Material removal rate Rotary tool

Improvement of machining consistency during through-mask electrochemical large-area machining

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Chinese Journal of Aeronautics 2019年第4期32卷 1051-1058页

作者： Guoqian WANG hansong li Chao ZHANG Di ZHU College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and Astronautics

Electrochemical machining(ECM) is an important machining technique for the aeronautical manufacturing industry. Through-mask ECM is a form of ECM for machining metal parts with a hole array. In order to extend the machining area, a serpentine flow channel with multiple curves was used for through-mask ECM. With the extension of the flow channel, ensuring a machining consistency along the flow channel has been a challenge. The electrolyte conductivity is the main factor affecting the machining consistency. To analyze the change rules of the electrolyte conductivity, variations in the bubble rate and the temperature of the electrolyte in the electrolyte flow were explored under different power sources. Results indicate that pulse-power machining can reduce variations in the bubble rate and the temperature in the serpentine flow channel, and then the electrolyte conductivity can be stabilized within a very small range. Experiments using through-mask ECM were conducted in two types of power sources. Experimental results support the importance of pulse-power machining. A 14×28 hole array with a 2.5 mm diameter was fabricated by a pulsed power source. The aperture deviation of the hole array is less than 0.05 mm, and the roundness deviation is less than 15 lm when fabricated with pulse machining.

关键词： Hole array Numerical simulation Pulse machining Serpentine flow channel Through-mask electrochemical machining

Electrochemical micromachining of micro-dimple arrays on cylindrical inner surfaces using a dry-film photoresist

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Chinese Journal of Aeronautics 2014年第4期27卷 1030-1036页

作者： Qu Ningsong Chen Xiaolei li hansong Zeng Yongbin College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and Astronautics Jiangsu Key Laboratory of Precision and Micro-Manufacturing Technology

The application of surface textures has been employed to improve the tribological performance of various mechanical components. Various techniques have been used for the application of surface textures such as micro-dimple arrays, but the fabrication of such arrays on cylindrical inner surfaces remains a challenge. In this study, a dry-film photoresist is used as a mask during through-mask electrochemical micromachining to successfully prepare micro-dimple arrays with dimples 94 lm in diameter and 22.7 lm deep on cylindrical inner surfaces, with a machining time of 9 s and an applied voltage of 8 V. The versatility of this method is demonstrated, as are its potential low cost and high efficiency. It is also shown that for a fixed dimple depth, a smaller dimple diameter can be obtained using a combination of lower current density and longer machining time in a passivating sodium nitrate electrolyte.

关键词： Dry-film photoresist Electrochemical machining Electrochemical micromachining Inner surface Micro-dimple arrays Texture

Simulation and experimental investigation of inner-jet electrochemical grinding of GH4169 alloy

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Chinese Journal of Aeronautics 2018年第3期31卷 608-616页

作者： hansong li Shuxing FU Qingliang ZHANG Shen NIU Ningsong QU College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China AVIC Jincheng Nanjing Engineering Institute of Aircraft Systems Nanjing 211106 China

GH4169 alloy is one of the most commonly used materials in aero engine turbine blades,but its machinability is poor because of its excellent strength at high temperatures. Electrochemical machining（ECM） has become a common method for machining this alloy and other difficult-tomachine materials. Electrochemical grinding（ECG） is a hybrid process combining ECM and conventional grinding. In this paper, investigations conducted on inner-jet ECG of GH4169 alloy are described. Two types of inner-jet ECG grinding wheels were used to machine a flat bottom *** machining process was simulated using COMSOL software, and machining gaps under different machining parameters were obtained. In addition, maximum feed rates and maximum material removal rates under different machining parameters were studied experimentally. The maximum sizes and the uniformity of the distributions of the gaps machined by the two grinding wheels were compared. The effects of different applied voltages on the machining results were also investigated.

关键词： Electrochemical grinding GH4169 alloy Inner-jet Material removal rate Maximum feed rate

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螺旋桨与进气道内外流一体化仿真研究

Mold deformation in soft UV-nanoimprint lithography

中国科技纵横 2024年第9期 97-102页

作者：赵赟杰李伟郑强阮华波李寒松南京航空航天大学机电学院江苏南京 210000 中国航发湖南动力机械研究所湖南株洲 412002 中国航发湖南动力机械研究所湖南株洲 412002 湖南南方通用航空发动机有限公司湖南株洲 412002

工作状态下螺旋桨与进气道之间存在强烈的气动干扰,会对螺旋桨及进气道造成一定影响.为了探究两者之间相互影响的规律,本文利用内外流一体化三维数值仿真方法,对某涡桨发动机开展螺旋桨与进气道匹配仿真研究,重点研究螺旋桨性能与进气... 详细信息

工作状态下螺旋桨与进气道之间存在强烈的气动干扰,会对螺旋桨及进气道造成一定影响.为了探究两者之间相互影响的规律,本文利用内外流一体化三维数值仿真方法,对某涡桨发动机开展螺旋桨与进气道匹配仿真研究,重点研究螺旋桨性能与进气道出口截面特性参数之间的相互影响规律,为后续螺旋桨及进气道的设计及优化提供理论支持和基础方法.研究结果表明,本文采用的数值计算方法对螺旋桨性能计算具有较高的可信度,基本符合螺旋桨三维仿真需求;螺旋桨性能参数基本不受螺旋桨与进气道之间气动干扰的影响;螺旋桨与进气道之间气动干扰主要对进气道产生影响:进气道出口截面DC60 受来流马赫数、螺旋桨转速以及进气道出口背压共同作用,其随来流马赫数的增大递减、随螺旋桨转速以及进气道出口背压的增大递增.

关键词：螺旋桨进气道内外流仿真

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Science China(Technological Sciences) 2009年第2期52卷 294-302页

作者： LAN HongBo DING YuCheng liU HongZhong QUE YeRong TAO WeiWei li hansong LU BingHeng State Key Laboratory for Manufacturing System Engineering Xi’an Jiaotong UniversityXi’an 710049China School of Mechanical Engineering Shandong UniversityJinan 250061China

UV-nanoimprint lithography (UV-NIL) using a soft mold is a promising technique with low cost and high throughput for producing the submicron scale large-area patterns. However, the deformations of the soft mold during imprinting process which can cause serious consequences have to be understood for the practical application of the process. This paper investigated the deformation of the soft mold by theoretical analyses, numerical simulations, and experimental studies. We simulated the mold deformation using a simplified model and finite element method. The simulation and the related experimental results agree well with each other. Through the investigation, the mechanism and affected factors of the mold deformation are revealed, and some useful conclusions have been achieved. These results will be valuable in optimizing the imprinting process conditions and mold design for improving the quality of transferred patterns.

关键词： UV-nanoimprint lithography (UV-NIL) soft mold deformation numerical simulation finite element model

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曲面电解铣削加工电场仿真分析与试验研究

机械设计与制造工程 2024年第9期53卷 47-51页

作者：吴红傲李寒松卢俞廷崔振南京航空航天大学机电学院江苏南京210016

复杂曲面结构被广泛应用于航空航天、汽车、精密仪器等多个领域。基于大尺寸、难加工薄壁曲面结构零件进行曲面电解铣削加工研究,设计了3种不同出液口形式的工具阴极进行电场仿真分析与实验研究。电场仿真结果表明,采用工具阴极C进行电... 详细信息

复杂曲面结构被广泛应用于航空航天、汽车、精密仪器等多个领域。基于大尺寸、难加工薄壁曲面结构零件进行曲面电解铣削加工研究,设计了3种不同出液口形式的工具阴极进行电场仿真分析与实验研究。电场仿真结果表明,采用工具阴极C进行电解铣削加工时,加工表面具有更高的电流密度。实验结果表明,工具阴极C具有更高的材料去除率,且加工后工件表面轮廓更贴近理想加工轮廓。随着工具阴极进给速度的增加,工件的材料去除率也越来越高。

关键词：曲面电解铣削加工电流密度材料去除率

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辅助阳极掩模板电解加工技术

南京航空航天大学学报 2010年第4期42卷 401-406页

作者：李冬林朱荻李寒松南京航空航天大学机电学院南京210016

为了提高掩模板电解加工精度,本文采用辅助阳极法改善掩模板电解加工过程中侧面间隙电场的分布,减少杂散腐蚀。建立了未采用辅助阳极和采用辅助阳极电解加工的数学模型,模拟过程中考虑非线性电解液对加工精度的影响,利用有限元分析技术... 详细信息

为了提高掩模板电解加工精度,本文采用辅助阳极法改善掩模板电解加工过程中侧面间隙电场的分布,减少杂散腐蚀。建立了未采用辅助阳极和采用辅助阳极电解加工的数学模型,模拟过程中考虑非线性电解液对加工精度的影响,利用有限元分析技术分别对未采用辅助阳极和采用辅助阳极电解加工的蚀除过程进行了模拟和数值求解。结果显示:辅助阳极法有效地减弱了凹坑侧壁的电场密度,降低了侧向蚀除速度。以电解加工微小群孔结构为例,进行了未采用辅助阳极和采用辅助阳极电解加工对比实验,实验结果表明:辅助阳极能有效地抑制发生在侧壁的杂散腐蚀,减小孔的锥度,提高加工精度。

关键词：电解加工电场加工精度辅助阳极