文章介绍了电火花成型加工、电火花线切割加工的工艺原理、加工特点,通过对电火花加工原理和加工特点的介绍,进而介绍了电火花加工在模具制造中广泛应用。

This paper describes the process principle, process characteristics of EDM and WEDM, introduces the principle and characteristics, then introduces the application electrical discharge machining in mould manufacturing.

宏观力小、可控性好、加工质量高是电火花加工的显著优点,特别是能加工各种复杂表面工具和高硬度、特殊性能的材料。因此,电加工在模具等精密零件加工中得到广泛应用。但是,模具精度要求越来越高,对应的加工设备性能指标要求也越来越苛刻。因此提高电火花线切割加工精度面临十分迫切的需求,这其中主要涉及到电火花放点过程、电火花加工机理、电火花加工工艺参数优化关键理论,这些都是目前国内外研究的热点问题。

EDM electrode and the workpiece with macroscopic force is small,good controllability,etc.,so that it can process a variety of special properties of materials and a variety of complex surface of the workpiece, such as precision machining parts in the mold has been widely used. However, more and more high precision molds, and the corresponding processing equipment requirements are also increasing. Thereby, increasing the accuracy of WEDM is a very pressing need, which mainly related to the spark discharge point process,EDM mechanism and optimization of process parameters. These are currently hot research issues.

微小孔加工时的放电间隙较小,排屑、消电离状态差,放电效率低,直接影响加工效率和电极损耗;超声振动可改善排屑、消电离状态,能提高放电效率。将超声引入微细电火花加工,通过工件的超声振动,进行超声功率、小孔孔径、脉冲频率的微小孔电火花加工工艺试验研究,结果表明:加工不同孔径时,超声功率及电源频率都存在一个最佳值;加工条件合适时,超声复合微细电火花加工优于常规微细电火花加工。

The discharge gap was very small,the state of chip removal and deionization was poor and discharge rate is low when the micro hole was machining. Ultrasonic vibration assisted could improve the state of chip removal,deionization and discharge rate. While ultrasonic vibration was used to micro eletro-discharge machining ,the experiments of micro eletro-discharge machining were carried out on ultrasonic power,hole diameter,pulse frequency. The result shows that ultrasonic power and power frequency had optimum values when hole of different sizes were machined. If machining conditions were right,ultrasonic assisted micro electro-discharge machining would be better than conventional micro electro-discharge machining.

提出了一种使用超声振动辅助混粉电解电火花铣削加工硬脆性非导电材料的方法。通过对高硼玻璃进行超声振动作用下的混粉电解电火花铣削加工实验,研究了超声振动对电解电火花铣削加工表面质量的影响规律。结果表明:采用超声振动辅助混粉电解电火花加工,可获得较好的表面质量。

A machining method of non-conductive hard and brittle materials with ultrasonic vibration assisted powder -mixed electrochemical discharge machining is proposed. Through the experiment of milling pyrex glass in powder-mixed electrochemical discharge machining assisted with ultrasonic vibration,the effect rules of ultrasonic vibration on the milling surface quality is researched. The experiment results show that powder-mixed electrochemical discharge machining with ultrasonic vibration assisted can acquire better surface quality.

为克服传统电火花加工的复杂形状电极制备周期长、大面积复杂型腔加工效率低的弊端,提出了一种用于粗加工的多孔质电极电火花加工新方法。采用紫铜颗粒高温烧结的方式实现多孔质电极的快速制备,利用多孔质电极中的孔隙实现内冲液,以达到电火花粗加工过程中快速去除材料的目的。并可采用电极端部、侧部冲液相结合的方式,提高复杂型腔电火花加工的效率。通过对多孔质电极烧结制备的实验研究,初步确定了多孔质电极的烧结工艺参数。通过加工实验证明了多孔质电极电火花加工的可行性。

To address the long preparation period of complexity electrode and the low efficiency of large and complicated cavity machining in traditional EDM ,a new method by using porous electrode in EDM roughing machining is proposed. A high temperature sintering of copper particles way to achieve rapid preparation of porous electrode is utilized ,to provide pores of porous electrode for inner flushing to improve the material removal ratio during EDM roughing machining. By means of applying flushing on both tip and side part of the electrode ,the efficiency of complex cavity EDM process is improved. Through the fabrication of porous electrodes sintering ,the sintering process parameters of porous electrode is identified. Feasibility of EDM with a porous electrode is proved by a series of processing experiment results.