振动进给对微尺度群缝电解加工过程的影响

为精确控制振动进给运动,研制了多参数可调的电解加工振动进给装置系统。通过对工具阴极振动进给方式对电解加工间隙内电解产物排出、电解液流场稳定性影响的分析,以剃须刀网罩上的微尺度阵列群缝的电解加工为研究对象开展了系列工艺试验,研究了振动进给的运动参数对微尺度群缝的平均缝宽、侧壁锥度的影响,据此优选了工艺参数,并成功批量加工出了缝宽为0.26mm、侧壁锥度小于5%的微尺度阵列群缝。试验结果证明,振动进给能够有效提高微尺度群缝的电解加工精度和加工过程稳定性。     

微细群缝的精密电解加工研究

以某辐射状分布微细群缝结构的电解加工为研究对象，讨论了电解液、工件材料、加工速度等因素对加工精度的影响，结合研制的加工电极设计流场分布，优化加工参数，实现了以较高的效率加工出缝宽小至0．27mm的微细群缝结构，缝宽一致均匀，加工稳定性和重复性均好。     

基于电场仿真的微尺度群缝电解加工技术研究

以静刀盖微尺度群缝电解加工为研究对象,针对工艺试验过程中群缝成形规律难以掌握,试验参数修正周期长的问题,采用COMSOL软件对单缝成形过程进行了电场仿真,并以电场仿真参数结果进行工艺试验,加工出平均缝宽0.27mm,侧壁锥度为0.12的群缝结构。电场仿真与工艺试验结果对比表明,电场仿真方法减少了工艺试验中大量试验参数的修正工作,缩短了电解加工工艺试验周期,且电场仿真与工艺试验单缝最大形状误差在0.03mm以内。     

一种机器人柔性元件电解加工装置设计

机器人的柔性运动和自适应性能需求促进了柔性元件的迅猛发展,传统加工方法难以加工柔性元件的微尺度群缝结构.针对柔性元件加工群缝结构的需求,设计了一套用于微尺度群缝电解加工装置、一种用于进行微尺度群缝电解加工的工具阴极,以及一种用于进行定位和夹紧工件的专用夹具.加工方法采用机械式振动电解加工,可以保证较高的加工精度,阴极创新设计了数个筋状凸起用以加工工件,专用夹具设计有夹具盖,可起到密封电解液作用.该装置加工精度高,工具阴极和夹具易于加工,可以加工出符合要求的元件.     

电解线切割加工技术试验研究

分析了应用电解线切割加工工艺在厚不锈钢板上加工高深宽比结构的可行性。为解决加工高深宽比结构时的排屑问题,在分析该工艺特点的基础上,采用了轴向冲液的方法。在自行搭建的加工系统中,进行了不同加工参数的一系列试验,以研究加工电压、电极丝进给速度、电解液浓度和冲液速度对该工艺的影响。最后,对电解线切割加工参数进行优化,加工出了缝宽为160μm、深宽比高达30的微型花键。     

窄缝精密电解加工的实验研究

通过在理论上分析窄缝电解加工中片状电极和丝状电极对加工间隙和流场分布的影响,提出了采用小直径丝状电极提高加工精度和改善加工稳定性的方法。文中分别进行了片状电极和丝状电极之间、不同直径丝状电极之间的窄缝电解加工对比试验。结果表明,小直径丝状电极可以减小电解液流过电极丝产生的涡流死水区,改善加工区内的电解液更新和电解产物的排除,提高加工精度和加工过程的稳定性。     

电极平动式电解孔加工技术研究

从电解液流动角度对影响电解孔加工过程的主要原因进行了分析 ,提出利用电极平动来改善电解加工过程稳定性和提高加工精度 ,研制了电极平动系统 ,进行了加工试验。试验结果表明 ,电极的平动运动使得电解液分布变得均匀 ,消除了空穴和分离流等弊端 ,改进了过程稳定性 ,显著提高了加工精度。     

管电极电解加工工艺过程稳定性研究

为提高管电极电解加工的稳定性,对管电极电解加工的极间流场进行建模仿真,分析底面流场分布与加工稳定性的关系。仿真所得到的底面压强分布变化规律表明,侧面间隙、底面间隙以及电解液流速均对底面流场分布有重大影响,从而影响管电极电解加工的过程稳定性。结合仿真分析,通过对影响加工稳定性的主要工艺参数,如绝缘层的涂覆厚度、工具进给速度、电解液供液压力进行优化,减少深小孔加工中火花、短路等现象的发生。采用优化的参数,利用群电极成功加工出深宽比为2的7×7小孔阵列,加工过程稳定,孔径均匀。     

整体叶轮叶间槽数控电解加工的试验研究

运用数控电解加工的方法,通过正交试验,在分析阴极缝宽、加工电压、电解液压力、主轴转速等试验因素的基础上,对整体叶轮叶间槽的加工进行试验研究,并得到优化参数.试验结果表明,运用数控电解方法加工整体叶轮叶间槽有不可替代的优越性.     

直线刃阴极电解加工的试验与过程仿真

为了便于过程控制和工艺参数选择,利用直线刃阴极进行了电解加工平面的试验,总结了工艺参数对切削深度和表面质量的影响规律;基于电解加工理论,建立并求解了加工过程电场的数学模型,得到了工件阳极表面的变化曲线,分析了切削深度实测值与计算值的误差,结果表明:可以利用该模型进行电解加工过程的模拟、工艺参数的预测以及加工精度的分析。     

Micro wire electrochemical machining with an axial electrolyte flow

Micro wire electrochemical machining is a useful technique to produce high-aspect-ratio slit micro-structures. To improve processing stability, the axial electrolyte flow is adopted to renew electrolytes in the machining gap. A wire electrochemical micro-machining system with an axial electrolyte flow unit is developed. A mathematical model of tool feed rate is presented. To investigate the influence of electrolyte flow on processing stability and machining efficiency, comparative experiments were carried out. The influence of applied voltage and electrolyte concentration on machining accuracy is studied and the parameters such as electrolyte flow rate and applied voltage are optimized. Low initial machining gap is applied to decrease the stray current machining in the initial machining period. With the optimal parameters, the high-aspect-ratio micro spline and curved flow channel with the slit width of 160?μm have been fabricated on 5-mm-thick stainless steel (0Cr18Ni9). The width of the slit is uniform and the aspect ratio is 31.     

渐开线内花键电解加工流场设计及工艺稳定性研究

为进一步提高渐开线内花键电解加工的工艺稳定性,基于数值分析方法探讨了电解液流动方式、工具阴极结构、电解液参数对流场分布的影响规律。数值分析结果表明：电解液侧向流动可以改善加工区入口处电解液流速分布均匀性;带有导流段的变截面阴极能够降低工件表面流速波动。针对工艺稳定性及加工定域性,开展了渐开线内花键电解加工试验研究。试验结果表明：进给速度可达2.1 mm/min以上,齿形误差可控制在0.015 mm以内,当加工深度为30 mm时,齿向误差在0.02 mm以内。该加工方式的效率及精度能够满足很多实际需求,具有明显的技术经济优势。     

Optimize the flow field during counter-rotating electrochemical machining of grid structures through an auxiliary internal fluid flow pattern

Flow field distribution plays a vital role in electrochemical machining (ECM) because it can directly affect the machining stability and accuracy of ECM. In counter-rotating electrochemical machining (CRECM), the uniformity of the flow field is difficult to control due to the complicated and changeable flow channel shape. Through the simulation of the conventional lateral fluid flow pattern, it is found that the complexity of the flow channel with grid structures makes the flow field of machining area strongly disordered, which leads to the low velocity zones and dead zones. Based on the simulation results, a new electrolyte flow pattern with an auxiliary internal fluid is proposed, which can remarkably improve the uniformity of flow field by apply supplementary electrolyte to the machining area. Experimental results show that the new flow pattern effectively improves the machining stability of CRECM, and enhances the machining precision of grid structures, the sidewall taper angle is reduced from 29.3° to 7.7°.     

Flow field design and experimental investigation of electrochemical machining on blisk cascade passage

Electrochemical machining (ECM) provides an economical and effective way for machining heat-resistant, high-strength materials into complex shapes that are difficult to machine using conventional methods. It has been applied in several industries, especially aerospace, to manufacture blisk. The electrolyte flow field is a critical factor in ECM process stability and precision. To improve the process stability and the efficiency of blisk cascade passages, ECM with a radial feeding electrode, a rational electrolyte flow mode for electrochemical machining called “Π shape flow mode”, is discussed in the paper. Three flow field models are described separately in this report: traditional lateral flow mode, positive flow mode and Π-shaped flow mode, and the electrolyte velocity and pressure distribution vectors for each flow mode are calculated by means of a finite element fluid analysis method. The simulation results show that the electrolyte flow is more uniform with the Π-shaped flow mode. The deformation of the cathode, which is caused by the pressure difference, is also analysed in this report. The cascade passage ECM with a radial feeding electrode was experimentally tested out to evaluate the rationality of the flow field, and the fluctuation of current during the process was less than 1 %, which means that the process that uses the Π-shaped flow mode is stable. The feeding velocity of the cathode with the Π-shaped flow mode is approximately 70 % higher than that with the other two flow modes, and the incidences of short circuiting are obviously decreased. The surface roughness of the blisk hub is only 0.15 μm, and the machining error of the hub is less than 0.1 mm. The results demonstrate that using the Π-shaped flow mode can enhance the quality, stability and efficiency of blisk cascade passage ECM.     

长窄型薄壁叶片的套料电解加工

为实现长窄型薄壁叶片的套料电解加工,设计了电解液沿叶片轮廓四周进液的流动方式,开展了导流式出液和开放式出液的仿真对比分析,结果表明,导流式出液可以明显改善加工区域内流场的均匀性。开展了薄壁叶片套料电解加工试验研究,在进给速度1.4 mm/min下实现了薄壁叶片的套型加工,轮毂表面粗糙度从0.532 μm 降低至0.307 μm,叶片型面粗糙度从0.816 μm 降低至0.583 μm。