基于DSP—MCU的电火花加工智能控制器的设计

针对电火花加工的实时加工状态稳定问题,设计了一种基于DSP-MCU实现径向基函数(RBF)神经网络控制的电火花加工智能控制器,其能够根据加工工艺指标和加工过程中采集的实时数据,自动完成电火花加工机床在线参数的调整.测试结果证明所设计的控制器具有比较明显的控制效果.     

基于ISA总线的电火花线切割脉冲电源研究

为了提高电火花加工自动化和智能化程度,更方便地实现电火花加工脉冲电源的实时控制,在现有的脉冲电源基础上开发了一种基于ISA总线的电火花脉冲电源。在系统软件中,编制了电火花加工的电参数数据库,用户能根据数据库中提供的电参数或根据用户的需求方便地设置加工电参数。在硬件系统中采用了AT89C51单片机与8253作为核心产生脉冲信号,结构简单,脉冲周期范围大。     

主轴伺服系统参数对混气电火花加工性能影响的研究

利用混气电火花加工装置,进行了HCD-400电火花成形机主轴伺服系统的混气电火花加工实验.介绍了主轴伺服系统参数对混气电火花加工性能的影响规律,并对所产生的加工现象进行了分析.     

弯曲孔电加工工艺的实验研究

实验研究探讨了一种使用线框电极的电火花套料加工的新工艺.根据正交试验方法来分析精加工时加工参数对加工速度、电极损耗和加工表面粗糙度的影响,以确定套料精加工时最佳的电规准参数.依据直孔套料加工参数在模具材料中加工出了圆弧弯曲孔.     

石墨电极在线修复加工条件参数的实验研究

为了解决电火花加工成型电极在线修复问题,基于已有电火花加工机床的加工条件参数,提出了石墨电极在线逆向加工的修复方法。首先根据电火花加工经验设计了加工条件参数的逆向加工实验方案,然后针对不同的放电时间、放电休止时间、峰值电流、辅助回路、伺服速度等主要条件参数进行了电极逆向加工实验,从而得到了它们对石墨电极融蚀的影响,并通过分析与归纳,总结出了石墨电极在线逆向加工所需条件参数,最后通过逆向加工修复和逆向加工制作石墨电极对这些加工条件参数进行了验证。实验研究结果表明,在现有电火花加工机床上通过选择合适的加工条件和参数,在线逆向加工修复石墨电极的方法是可行而且高效的。     

基于智能技术的电火花加工过程建模和参数优化

根据电火花加工工艺特点 ,建立基于遗传算法的加工过程人工神经网络模型 ,实现加工结果的预测。根据预测结果 ,在保证表面粗糙度要求的前提下 ,以最大加工速度为目标 ,用遗传算法实现加工参数的优化。实验结果表明以上算法可有效解决电火花加工条件优化的问题 ,自动生成加工参数 ,而且收敛速度较快 ,满足机床控制的要求。     

基于GA-RBF神经网络的电火花成形加工电参数优化

针对电火花成形加工的电参数选择问题,先建立RBF神经网络,将加工电参数和工艺指标参数分别作为神经网络的输入和输出.然后用GA优化RBF神经网络,建立用于电火花成形加工电参数优化的GA-RBF神经网络模型.试验结果表明,该网络的精度是令人满意的.     

工程陶瓷材料电火花线切割加工的机理研究

针对如何提高工程陶瓷材料加工质量这一问题,对碳化硼工程陶瓷进行了电火花线切割加工的试验研究.介绍了工程陶瓷材料的电火花放电加工原理,通过对碳化硼工程陶瓷进行的电火花线切割加工工艺试验,探讨了电参数对工程陶瓷电火花线切割加工表面质量的影响规律.该研究对进一步深化电火花加工技术的基础理论,促进该技术在实际生产中的推广应用具有重要意义.     

先进的电火花成形机床的技术性能

由于电火花加工具有机床切削加工所不具备的许多特点,因而在民用、国防生产部门以及科学研究领域都已得到越来越广泛的应用.根据加工过程中工具与工件相对运动的特点和用途,电火花加工可分为以下几类:电火花成形(包括电火花穿孔和型腔加工)、电火花线切割、电火花磨削、电火花展成加工、电火花表面强化、非金属电火花加工以及其他电火花加工等.其中又以电火花成形加工和电火花线切割应用最广,两者分别占电火花加工总量的45%左右.本文着重介绍电火花成形机床的先进技术性能.     

电火花线切割五轴联动加工运动规律及仿真研究

为研究空间曲面的加工过程和规律,提出电火花线切割五轴加工计算机仿真技术研究方法.分析了空间曲面电火花线切割加工的特点及运动规律,建立了电火花线切割多轴加工系统运动的数学模型.通过运行相应的仿真程序,可以在计算机上直接观察到电火花线切割加工的全部过程,获得了比较理想的仿真结果.仿真所得到的理想加工参数为复杂零件加工提供了理论基础.从而拓宽了电火花线切割加工的工艺范围,解决了空间曲面零件的加工难题.     

模糊控制微细孔电火花加工研究

分析了微细孔电火花加工脉冲识别,提出以间隙平均电压、火化率偏差和火化率偏差变化为模糊控制器的3个输入控制参数,建立了微细孔电火花模糊控制加工策略,同时比较说明了模糊控制器对微孔电火花加工性能影响,实验结果说明模糊控制器对微细孔电火花加工系统更为有效,加工过程更加平稳。     

An experimental investigation into the micro-electrodischarge machining behavior of p-type silicon

The present study aims to investigate the feasibility of micro-structuring in p-type silicon, using conventional die-sinking electrodischarge machining (EDM). The EDM behavior of the silicon material is studied in terms of the effect of major operating parameters on the performance characteristics during the micro-hole machining. In addition, microelectrodes are fabricated successfully on the conventional EDM machine for machining different micro-structures in silicon. Three different types of micro-structures??micro-hole, blind slots, and through slots??are fabricated in p-type silicon successfully by using optimum parameters setting. It has been observed that p-type silicon is machinable by EDM using both the polarities. Moreover, like other electrodischarge machinable materials, the selection of optimum operating parameters is very important for improved performance, as those parameters are found to influence the EDM performance of silicon significantly. Finally, it has been concluded that p-type silicon is machinable into different forms of micro-structures by understanding its electrodischarge machining behavior and by careful selection of optimum parameters.     

基于Windows平台智能模糊控制电火花数控系统

利用Ｗ ｉｎｄｏｗ ｓ 消息驱动机制和时钟中断,成功地解决了数控电火花加工中多任务和实时任务处理的问题。介绍了该数控系统的功能组成和主画面的构成,并针对系统主要模块,即电火花加工智能自选规准、电火花加工过程模糊控制系统、多轴联动控制等进行分析和介绍,最后介绍了系统的应用情况。     

Comprehensive servo control strategies for flexible and high-efficient wire electric discharge machining. A systematic review

The increasing adoption of exotic and hard to cut materials in high-end applications makes electric discharge machining (EDM) process more relevant than ever. In particular, wire EDM variant (WEDM) deserves attention due to its ability to cut the workpiece's surroundings without completely evaporating the unused portion of the rare and expensive exotic materials. However, WEDM is a stochastic process that still lacks complete mathematical models and is driven by a myriad of parameters that will make its control a complex task. In WEDM, whenever the wire is fed too fast, the process will be interrupted not only by short circuits, but the wire electrode is most likely to break, jeopardising process efficiency in many ways. Currently, most of the literature has focused efficiency efforts in proposing a trade-off among parameters without a complete correlation with servo and control strategies. Therefore, this review aims to find and analyse the state-of-the-art approaches for controlling the Wire EDM process. A systematic literature review is conducted to identify and provide an adequate understanding of the best control strategies, fundamental parameters, and role. With no previous studies found, the present review focuses exclusively on servo control. First, it provides a comprehensive literature framework covering four decades, to next glimpse future developments of WEDM control strategies. Potential adoption of the findings can result in a deeper understanding of control variables and a broader and more efficient concept for WEDM servo feed control.     

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。     

Assessing the effects of different dielectrics on environmentally conscious powder-mixed EDM of difficult-to-machine material (WC-Co)

Electrical discharge machining (EDM) is a well-known nontraditional manufacturing process to machine the difficult-to-machine (DTM) materials which have unique hardness properties. Researchers have successfully performed hybridization to improve this process by incorporating powders into the EDM process known as powder-mixed EDM process. This process drastically improves process efficiency by increasing material removal rate, micro-hardness, as well as reducing the tool wear rate and surface roughness. EDM also has some input parameters, including pulse-on time, dielectric levels and its type, current setting, flushing pressure, and so on, which have a significant effect on EDM performance. However, despite their positive influence, investigating the effects of these parameters on environmental conditions is necessary. Most studies demonstrate the use of kerosene oil as dielectric fluid. Nevertheless, in this work, the authors highlight the findings with respect to three different dielectric fluids, including kerosene oil, EDM oil, and distilled water using one-variable-at-a-time approach for machining as well as environmental aspects. The hazard and operability analysis is employed to identify the inherent safety factors associated with powder-mixed EDM of WC-Co.     

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.     

基于支持向量机的电火花加工8418钢表面粗糙度预测模型

由于电火花加工过程的复杂性,单纯通过电火花加工实验方法研究各种放电参数及非电参数对工件表面粗糙度Ra的影响不但耗费大量时间,而且实验成本较高,为此基于支持向量机提出了一种适用于电火花加工表面粗糙度预测的模型。利用遗传算法对该模型中的各参数进行优化,预测不同电火花加工参数组合下的表面粗糙度;以电火花加工8418模具钢为例,将预测值与实验值进行对比,并且通过实验验证了电火花加工8418钢表面粗糙度预测模型参数的准确性;最后进行了误差分析,模型的最大误差值为2.27%。     

Optimization of machining parameters in rotary EDM process by using the Taguchi method

Electrical discharge machining (EDM) is one of the advanced methods of machining. Most publications on the EDM process are directed towards non-rotational tools. But rotation of the tool provides a good flushing in the machining zone. In this study, the optimal setting of the process parameters on rotary EDM was determined. A total of three variables of peak current, pulse on time, and rotational speed of the tool with three types of electrode were considered as machining parameters. Then some experiments have been performed by using Taguchi's method to evaluate the effects of input parameters on material removal rate, electrode wear rate, surface roughness, and overcut. Moreover, the optimal setting of the parameters was determined through experiments planned, conducted, and analyzed using the Taguchi method. Results indicate that the model has an acceptable performance to optimize the rotary EDM process.