粉末特性对混粉电火花镜面加工的影响

用实验方法研究了粉末粒度、形状及导电性对混粉电火花镜面加工表面粗糙度的影响,同时对混粉电火花加工表面的耐磨性和耐蚀性进行了研究。结果表明,粉末粒度和导电性对混粉电火花加工表面粗糙度有较大的影响;混粉电火花镜面加工不但能改善加工表面粗糙度,且能提高加工表面的耐磨性和耐蚀性。     

混粉电火花镜面加工表面性能研究

利用自行研制的混粉电火花镜面加工装置,以淬火状态的8407模具钢为例,对多种添加粉末下的混粉电火花镜面加工表面性能进行了研究。研究结果表明,混粉电火花镜面加工不但能够显著降低加工表面粗糙度值,而且能够提高加工表面的耐磨性、耐蚀性和表层显微硬度。     

混粉电火花加工工艺初探

介绍了混粉电火花加工工艺的发展概况，解释了混粉电火花加工中出现的一些现象。文章认为，在一定加工时间的保证下（１５ｈ） ，选择合理的加工规准，能够用混粉电火花加工机床加工出面积为１００ｃｍ２ 、表面粗糙度Ｒａ 为０ ．１８３μｍ 的镜面。     

超声磨料混粉电火花复合加工的研究

阐述了超声磨料混粉电火花复合加工基本原理和基本设备，在试验研究的基础上对加工参数进行详细的讨论，分析了主要参数对表面粗糙度的影响。     

电参数对混粉镜面电火花加工表面粗糙度影响的研究

介绍了混粉镜面电火花加工的实验装置 ,并应用单因素法初步研究了脉冲电参数对混粉大面积镜面电火花加工工件表面粗糙度的影响规律。取得了 5 9mm加工表面最小表面粗糙度为 Ra0 .3μm的结果     

混粉电火花加工机理的分析

论述了混粉电火花加工的发展概况 ,并以实验为基础对其机理进行了分析 ,认为加工表面粗糙度的迅速降低主要是放电通道对熔融金属平整作用的结果。对于这一工艺的加工效率进行了剖析 ,认为从改善表面质量的角度来看 ,混粉电火花加工具有很高的加工效率。通过对电极损耗情况的观察 ,发现电极损耗特性也有一临界点 ,这一点与普通电火花加工相似     

基于神经网络的混粉电火花加工效果的预测模型

针对混粉电火花加工的工艺特点及其复杂性,提出了一个基于径向基函数（RBF）神经网络的混粉电火花加工效果的预测模型,并通过该模型对混粉电火花加工试验研究的工件表面粗糙度进行了预测,预测结果与实际试验结果有较好的一致性,说明RBF神经网络对混粉电火花加工效果的预测是有效的.     

电参数对混粉镜面电火花加工表面粗糙度影响的研究

介绍了混粉镜面电火花加工的实验装置,并应用单因素法初步研究了脉冲电参数对混粉大面积镜面电火花加工工件表面粗糙度的影响规律。     

混粉电火花加工在型腔模中的应用

混粉电火花加工是一种改善电火花加工表面粗糙度与加工效率的先进工艺方法,近几年在像手机外壳模具、遥控器外壳模具等型腔模的电火花精加工中发挥着越来越重要的作用.通过对型腔模混粉电火花加工应用技术的探讨,对模具制造企业吸收与消化当前先进的电火花加工工艺具有实际的应用价值.     

混粉准干式电火花精密加工技术研究

提出了一种混粉准干式电火花加工技术,其加工介质是气液固三相流混合物。研究了其单脉冲放电过程,一次放电过程可分为电离、击穿放电、抛出电蚀物及消电离4个阶段。并对比了气中放电、准干式电火花加工、混粉准干式电火花加工的材料去除率和表面粗糙度。实验结果表明,这3种加工方法材料去除率依次升高,表面粗糙度值依次降低。     

Machining characteristics of magnetic force-assisted EDM

The gap conditions of electrical discharge machining (EDM) would significantly affect the stability of machining progress. Thus, the machining performance would be improved by expelling debris from the machining gap fast and easily. In this investigation, magnetic force was added to a conventional EDM machine to form a novel process of magnetic force-assisted EDM. The beneficial effects of this process were evaluated. The main machining parameters such as peak current and pulse duration were chosen to determine the effects on the machining characteristics in terms of material removal rate (MRR), electrode wear rate (EWR), and surface roughness. The surface integrity was also explored by a scanning electron microscope (SEM) to evaluate the effects of the magnetic force-assisted EDM. As the experimental results suggested that the magnetic force-assisted EDM facilitated the process stability. Moreover, a pertinent EDM process with high efficiency and high quality of machined surface could be accomplished to satisfy modern industrial applications.     

Surface modification of Al–Zn–Mg alloy by combined electrical discharge machining with ball burnish machining

The study investigated the feasibility of modifying the surface of Al–Zn–Mg alloy by a combined process of electric discharge machining (EDM) with ball burnish machining (BBM). A novel process that integrates EDM and BBM is also developed to conduct experiments on an electric discharge machine. Machining parameters of the combined process, including machining polarity, peak current, power supply voltage, and the protruding of ZrO₂, are chosen to determine their effects on material removal rate, surface roughness and the improvement ratio of surface roughness. In addition, the extent to which the combined process affects surface modification is also evaluated by microhardness and corrosion resistance tests. Experimental results indicate that the combined process of EDM with BBM can effectively improve the surface roughness to obtain a fine-finishing and flat surface. The micropores and cracks caused from EDM are eliminated during the process as well. Furthermore, such a process can reinforce and increase the corrosion resistance of the machined surface after machining.     

Machining performance on hybrid process of abrasive jet machining and electrical discharge machining

To develop a hybrid process of abrasive jet machining (AJM) and electrical discharge machining (EDM),the effects of the hybrid process parameters on machining performance were comprehensively investigated to confirm the benefits of this hybrid process.The appropriate abrasives delivered by high speed gas media were incorporated with an EDM in gas system to construct the hybrid process of AJM and EDM,and then the high speed abrasives could impinge on the machined surface to remove the recast layer caused by EDM process to increase the efficiency of material removal and reduce the surface roughness.In this study,the benefits of the hybrid process were determined as the machining performance of hybrid process was compared with that of the EDM in gas system.The main process parameters were varied to explore their effects on material removal rate,surface roughness and surface integrities.The experimental results show that the hybrid process of AJM and EDM can enhance the machining efficiency and improve the surface quality.Consequently,the developed hybrid process can fit the requirements of modern manufacturing applications.     

石墨电极电火花加工工艺与电火花机床的适应性研究

通过正交实验,讨论电火花机床对石墨电极电加工的影响,并分析了石墨电极电火花加工工艺与电火花机床的适应性,得出主轴性能影响放电加工的稳定性,脉冲电源可以提高加工速度,工作液可以提高加工表面质量和加工速度。     

A study of EDM and ECM/ECM-lapping complex machining technology

EDM (electrodischarge machining) and ECM (electrochemical machining)/ECM-lapping complex machining is investigated in this paper. First, EDM shaping and ECM finishing technology are investigated. These processes are carried out in sequence on the same machine tool with the same electrode (copper) and the same machining liquid (water). Two types of EDM and ECM complex machining are investigated. One is with a formed electrode, and the other is with simple-shape electrode scanning. The complex machining with electrode scanning is applied to produce small and various-shaped components without making a formed electrode. The EDM surface of 1 μm Ra is improved to 0.2 μm Ra by applying ECM. Second, in order to get a smoother surface, a new EDM and ECM-lapping complex machining technology is developed. The surface roughness of a machined hole is improved to 0.07 μm Ra by applying 2 min of ECM lapping. The surface finishing of a hole shape is demonstrated with the complex machining technology.     

Performance and Surface Integrity of Ti6Al4V After Sinking EDM with Special Graphite Electrodes

Titanium and its alloys have high chemical reactivity with most of the cutting tools. This makes it difficult to work with these alloys using conventional machining processes. Electrical discharge machining (EDM) emerges as an alternative technique to machining these materials. In this work, it is investigated the performance of three special grades of graphite as electrodes when ED-Machining Ti6Al4V samples under three different regimes. The main influences of electrical parameters are discussed for the samples material removal rate, volumetric relative wear and surface roughness. The samples surfaces were evaluated using SEM images, microhardness measurements, and x-ray diffraction. It was found that the best results for samples material removal rate, surface roughness, and volumetric relative wear were obtained for the graphite electrode with 10-μm particle size and negative polarity. For all samples machined by EDM and characterized by x-ray (XRD), it was identified the presence of titanium carbides. For the finish EDM regimes, the recast layer presents an increased amount of titanium carbides compared to semi-finish and rough regimes.     

GT35钢结硬质合金电火花加工工艺试验

研究了GT35电火花加工时,峰值电流、脉冲宽度、放电时间等参数对工件加工效率、加工面粗糙度和电极耗损速度等的影响规律,并分析了其作用机理,优化了GT35钢结硬质合金电火花加工工艺参数,为加工复杂型腔GT35钢结硬质合金模具提供了试验依据。     

Influence of sonotrode texture on the performance of an ultrasonic consolidation machine and the interfacial bond strength

Ultrasonic consolidation (UC) has been successfully used in rapid tooling, prototyping and moulding, fibre and sensor embedding, and electronics embedding. To ensure consistent transfer of ultrasonic energy into workpieces, the surface texture of sonotrode is very important. This paper studied the effects and importance of the texture on the UC process. Monolithic Al 3003 H18 samples were consolidated by the alpha ultrasonic weld machine with a worn sonotrode and a newly electrical discharge machining (EDM)-modified sonotrode, and during the process the performance of the UC machine was monitored. Peel tests were conducted for the consolidated samples and the peel strength and linear weld density were compared. As expected, the results showed that UC machine performance improved with the EDM-modified sonotrode. After improving the surface texture of sonotrode, problems such as foil overlap and crinkling were solved. The results showed that an even and rough texture was necessary for the UC machine to achieve a good performance and a high energy transmission efficiency and the surface roughness of sonotrode may have a two-side influence, i.e. increasing void level and introducing more energy, on consolidation.     

超声振动磨削放电复合加工SiCp／Al试验研究

针对SiCp／Al的加工,提出一种超声振动磨削放电复合加工的方法．从加工效率、加工稳定性及表面质量等方面与电火花加工进行了对比试验研究。分析了两种加工方法的脉冲宽度和峰值电流对加工速度和表面粗糙度的影响,结果表明：电火花加工的表面粗糙度平均值为尺04．5μm,超声振动磨削放电复合加工的表面粗糙度平均值为Ra2μm：超声振动磨削放电复合加工的稳定性比电火花加工好,但加工速度较低。通过扫描电镜对两种加工方法下零件表面形貌和重熔层进行了观测,对试件表面进行了X射线衍射分析,表明采用超声振动磨削放电复合加工SiCp／Al复合材料可获得较好的表面质量。