微制造系统中的微细电火花加工技术

文章系统地研究和综述了微细电火花加工技术的研究现状和发展趋势，论述了微细电火花加工技术在微三维结构制作及微制造系统中的应用。     

微细电火花加工及其关键技术

综述了微细电火花加工的基本原理及最新研究进展。比较了LIGA技术与微细电火花加工的特点与应用。简要分析了微细电火花加工的关键技术：微细电极的在线制作、微进给装置、微小能量的脉冲电源、微小电极的运动轨迹规划、电极的损耗及补偿策略。展望了微细电火花加工在微三维结构加工中的应用前景。     

民火花微细加工系统研制

根据电火花微细加工的技术特点，设计研制适应电火花微细加工要求的伺服控制系统，微能脉冲电源和微细电极制造机构，整个系统工作稳定，能够较好地达到微细加工的要求。     

微细机械加工技术

随着微型机械的应用领域进一步拓展,微细机械制造加工技术得到了快速发展.在介绍了微细切削加工、微细电火花加工、微细蚀刻以及微细电解加工的基础上,对其加工特点和性能进行了比较,讨论了微细机械加工发展的方向与关键问题.     

电蚀产物对微细电火花电极形状损耗影响的实验研究

针对微细电火花加工技术特点，开展电极形状损耗形成机理的研究，设计了开放状态微细电火花加工实验方法,实现电蚀产物浓度的改变；通过实验对比不同加工状态下微细电火花加工电极形状损耗变化、工件表面微观形貌和重熔层情况，系统研究不同电蚀产物浓度作用下电极形状损耗的影响规律；分析微细电极形状损耗的影响机制，总结内凹坑形状变化与电蚀产物的内在关系。研究成果为实现微细电极的形状控制提供了一定的实验及理论依据，达到了提升微细电火花加工质量和加工稳定性的目标。     

微细电火花加工技术

本文介绍了微细电火花加工技术的研究开发现状,讨论了传统的电火花加工、线放电磨削加工等微细加工的方法及其应用。     

微细电火花加工中微细电极的制作与检测技术研究

分析了微细电火花加工技术中各种微细电极制作方法的特点,提出了一种加工效率与尺寸精度相兼顾的微细电极在线制作方法.充分利用微细电火花加工机床的数控和接触感知功能,探索并提出了一种微细电极的在线检测方法,并对检测误差进行了分析.实验表明,该方法具有广泛的实用性.     

新型多功能微细电火花加工机床及应用

微细电火花加工是微机电系统制造技术中最关键的技术手段之一。这里综述了当前国外生产厂家和研究机构的已经商品化和正在研制中的几种微细电火花加工机床的构成、功能、技术要点和典型应用,希望能为从事微细电火花加工机床的研制者提供一些有价值的信息。     

电致伸缩器件在电火花细微孔加工中的应用

本研究提出了一种新的电火花复合微细加工方法。采用电致伸缩器件使工件产生微幅激振，利用工件的微幅激振改善微细电火花加工工作液循环，提高了电火花微细孔加工的深径比。简单分析了这一加工机理和介绍了这一加工系统的组成，并用实验结果给予了验证。     

新型微能可控的MWEDM脉冲电源

分析了以往的微细电火花线切割加工(MWEDM)脉冲电源的不足。在现代电力电子技术基础上，开发出新型微能可控的微细电火花线切割加工脉冲电源。试验表明，这种高质量的脉冲电源为改善微细电火花线切割加工整体性能、拓展加工领域提供了技术保证。     

UV-LIGA和微细电火花加工技术组合制作三维金属微结构

为了制作三维金属微结构,研究了UV-LIGA和微细电火花加工技术组合的工艺方法。使用UV-LIGA技术制作了准三维金属微结构,然后,对该微结构进行微细电火花加工制作三维金属微结构。使用提出的方法制作出了局部为梯形凸台和锥形凹槽三维微结构的镍模具,给出了梯形凸台和锥形凹槽的尺寸。分析了微细电火花加工中放电参数对表面粗糙度的影响,在工作电压为65V,标称电容为100pF时得到了Ra为0.08μm的微细电火花加工表面。研究结果表明,使用该方法可实现三维金属微结构的制作;通过减小工作电压和标称电容的方法可降低微细电火花加工的表面粗糙度。     

High-efficiency approach for fabricating MTE rotor by micro-EDM and micro-extrusion

Micro-gas turbine engine（MTE） rotor is an important indicator of its property, therefore, the manufacturing technology of the microminiature rotor has become a hot area of research at home and abroad. At present, the main manufacturing technologies of the MTE rotor are directed forming fabrication technologies. However, these technologies have a series of problems, such as complex processing technology high manufacturing cost, and low processing efficiency, and so on. This paper takes advantage of micro electric discharge machining（micro-EDM） in the field of microminiature molds manufacturing, organizes many processing technologies of micro-EDM reasonably to improve processing accuracy, presents an integrated micro-EDM technology and its process flow to fabricate MTE rotor die, and conducts a series of experiments to verify efficiency of this integrated micro-EDM. The experiments results show that the MTE rotor die has sharp outline and ensure the good consistency of MTE rotor blades. Meanwhile, the MTE rotor die is applied to micro extrusion equipment, and technologies of micro-EDM and micro forming machining are combined based on the idea of the molds manufacturing, so the MTE rotor with higher aspect ratio and better consistency of blades can be manufactured efficiently. This research presents an integrated micro-EDM technology and its process flow, which promotes the practical process of MTE effectively.     

Scale effects and a method for similarity evaluation in micro electrical discharge machining

Electrical discharge machining(EDM) is a promising non-traditional micro machining technology that offers a vast array of applications in the manufacturing industry. However, scale effects occur when machining at the micro-scale, which can make it difficult to predict and optimize the machining performances of micro EDM. A new concept of “scale effects” in micro EDM is proposed, the scale effects can reveal the difference in machining performances between micro EDM and conventional macro EDM. Similarity theory is presented to evaluate the scale effects in micro EDM. Single factor experiments are conducted and the experimental results are analyzed by discussing the similarity difference and similarity precision. The results show that the output results of scale effects in micro EDM do not change linearly with discharge parameters. The values of similarity precision of machining time significantly increase when scaling-down the capacitance or open-circuit voltage. It is indicated that the lower the scale of the discharge parameter, the greater the deviation of non-geometrical similarity degree over geometrical similarity degree, which means that the micro EDM system with lower discharge energy experiences more scale effects. The largest similarity difference is 5.34 while the largest similarity precision can be as high as 114.03. It is suggested that the similarity precision is more effective in reflecting the scale effects and their fluctuation than similarity difference. Consequently, similarity theory is suitable for evaluating the scale effects in micro EDM. This proposed research offers engineering values for optimizing the machining parameters and improving the machining performances of micro EDM.     

微细电火花成形加工设备关键技术研究

基于微细电火花加工的要求,对微细电火花成形加工设备中的关键技术进行研究,成功研制了一套高精度的微细放电加工设备产品,包括一台微细电火花加工机床和一台精密脉冲电源。优化机床关键零/部件的结构后,机床的变形小,运动精度高;电源放电稳定,控制精确。经加工试验表明,该设备加工效果较好,加工精度和稳定性较高,加工出的窄槽工件的尺寸精度可达到5μm,加工直径为300μm的小孔,其圆度误差达到3μm,可满足微细电火花加工的要求。     

Review of size effects in micro electrical discharge machining

Electrical discharge machining (EDM) is one of the most promising non-traditional micro-scale machining methods. Because several operating parameters that are insignificant in macro EDM cannot be neglected during micro EDM process, models derived from the macro EDM process may be inappropriate at the micro scale. This paper contains a comprehensive review of size effects in traditional micro-machining and characteristics specific to micro EDM compared to macro EDM techniques. The very concept of size effects in micro EDM is thoroughly defined and three categories of effects are presented: material microstructure, processing parameter and thermal conduction size effects. Future potential research directions on the subject are also summarized. We assert that careful research and precise attention must be given to size effects in micro EDM. Size effect information especially benefits the machining speed and machining precision of micro EDM.     

微细电火花加工脉冲电源及智能控制器设计

设计了以DSP和CPLD为控制单元的微细电火花脉冲电源,满足微细电火花加工单个脉冲能量小而可控的要求。针对加工过程难以用数学模型描述的问题,利用智能控制不依赖数学模型的优势,设计了模糊神经网络控制器,根据间隙放电状态,对在线参数实时调整。通过微小孔加工实验表明,采用智能控制的加工方式可以提高加工速度,有很好的应用前景。     

A computer-aided design system for foot-feature-based shoe last customization

The micro-electrical discharge machining (micro-EDM) process has proved to be an appropriate nonconventional machining method for manufacturing accurate and complex three-dimensional structural micro-features which are difficult to be produced by conventional processes. However, the miniaturisation of the EDM process requests special requirements on the machining equipment. Pulse generators which can produce small input energy pulses and high precision systems are the two major requirements. In this paper, newly developed technologies regarding these aspects are explored with the aid of a commercial micro-EDM machine. By examining the pulses, innovative strategies implemented in the pulse generator are studied. Pulse measurements reveal the correlation between the discharge pulses and the machine parameters in order to provide an overview of process capability. Conclusions are applied on machining of a ceramic composite Si₃N₄-TiN and optimised machining settings for different machining conditions are achieved. Accordingly, applications of two- and three-dimensional micro-structures on different types of materials such as a stainless steel micro-compressor and a ceramic miniature gas turbine are demonstrated. By inspecting the machining geometry and surface integrity, process characteristics of micro-EDM are discussed.     

RESEARCH OF MICRO ELECTRO DISCHARGE MACHINING EQUIPMENT AND PROCESS TECHNIQUES

Micro electro discharge machining (micro EDM) is a feasible way to manufacture micro structures and has potential application in advanced industrial fields. For the realization of micro EDM, it is necessary to pay careful attention to its equipment design and the development of process techniques. The present status of research and development of micro EDM equipment and process techniques is overviewed. A micro electro discharge machine incorporated with an inchworm type of micro feed mechanism is introduced, and a micro electro discharge machine for drilling micro holes suitable to industrial use is also introduced. Some of the machining experiments carried out on the micro EDM prototypes are shown and the feasibility of the micro EDM technology to practical use is discussed.     

电火花成形机床微细加工相关探索

首先简要介绍了电火花微细加工目前的发展状况。并概括地分析了商品电火花成形机用于微细加工所具有的一些特殊优势。最后通过微轴的加工实例来证实其进行实用微细加工的可行性。