电解加工电源研究现状及发展趋势

电解加工电源是电解加工装备中的关键核心基础设备,其性能直接影响着电解加工的精度、稳定性、表面质量和经济性.为了更加充分发挥电解工艺的潜力和优势,实现精密、高效、稳定的电解加工,有必要对电解加工电源的研究现状及发展趋势进行系统梳理和全面总结.系统分析了宏观尺度电解加工和微细电解加工的工艺原理,加工质量、效率和工艺稳定性等的影响因素,归纳总结出不同类别、不同应用场合下电解工艺对加工电源的性能指标要求.较为全面地介绍了近年来国内外在电解加工电源方面的相关研究进展及应用情况.对电解加工电源在控制高频脉冲产生、信号处理与输出、加工间隙监测、电源保护等几个方面的关键技术进行了评述,同时对电解加工电源的发展趋势进行了预测和展望,为促进我国电解加工技术的快速发展和广泛应用提供有益的参考.     

电解加工电源的发展及特点

本文介绍了近几十年来电解加工电源的发展和性能特点。另外 ,还详细介绍了一种新型电解加工电源 :用于微小型零件加工的高频群脉冲电解加工电源。     

高频窄脉冲电流微细电解加工

微细电解加工是微细加工领域很有发展前景的微细加工技术之一。适合于微细电解加工的装置被研制出来, 它包括机床进给机构、线电极电火花磨削在线制作微细电极装置、短路检测模块、脉冲电源及其他一些辅助装置, 其中,高频窄脉冲电源是微细电解加工最重要的核心技术之一。根据微细电解加工的特点,设计了微细电解加工 MOSFET脉冲电源,该微能脉冲电源能很好地满足微细电解加工的要求。运用该微细电解加工装置进行加工试验, 在低的加工电压和低的钝化电解液浓度条件下,利用高速旋转的微细电极加工微小孔和像小铣刀一样进行微细电解铣削加工微结构,得到了满意的工艺效果,因而进一步说明电解加工在微细加工领域很有发展潜力。     

电解加工脉冲电源研制

介绍逆变式电解加工高频脉冲电源的设计原理、特点和各部分的电路结构，通过工艺试验对这种电源进行分析和说明。较高精度的加工效果，表明了逆变式电源方案的可行性。该电源具有重量轻、体积小、效率和频率高等优点。     

电解加工在微细制造技术中的应用研究

电解加工是利用阳极金属电化学溶解原理来去除材料的制造技术,这种微去除方式使得电解具有微细加工的可能,这里着重探讨了高频窄脉冲微细电解加工技术、电液束微细电解加工技术和利用电解制备微细电极的工作原理,技术特点,应用领域和加工精度,并详细的讨论了目前微细电解加工脉冲电源和加工设备的研制和发展。     

双极性高频脉冲电解电源的研制

根据电解-机械复合加工方法的特点,分析了加工所需脉冲电源的要求,设计了一种双极性脉冲电源.该电源采用PIC18F458单片机作为控制系统的核心,主电路采用双电源斩波结构,可实现双极性方波交流、直流、脉冲电流等多种输出.正负半波的幅值、频率及占空比均可调节,经实际使用,证明该电源具有稳定、可靠的特点,能满足电解复合磨削的工艺要求.     

电解加工脉冲电源间隙电压检测方法

脉冲电源在电解加工过程中需要控制脉冲电压与间隙配合,使加工稳定以提高精度,电压检测则是脉冲电源检测中重要环节。介绍了脉冲电源在电解加工过程脉冲电压的常用检测方法,分析其原理及特点,设计出一种简单稳定可靠,适用于高频可调脉冲电源电压隔离检测电路。     

高频群脉冲电解加工中IGBT反向尖峰电压的数学模型

在高频群脉冲电解加工电源的研究中发现电源的核心元件IGBT在关断瞬间会出现反向尖峰电压,由于对他的适当 控制对提高电解加工的精度和加工产品的表面质量起着至关重要的作用,针对这个问题我们建立了反向尖峰电压的数学模 型。本文就此数学模型进行了介绍,同时阐述了该模型的建立对抑制反向尖峰电压的作用。     

脉冲电解加工技术在精微加工领域中的新发展

介绍了高频、窄脉冲成形加工技术新的研究成果，考察了国外微细加工技术的新发展状况，结果表明：精密窄脉冲电解加工近年来向提高频率、缩短脉宽方向发展；大电流、高频、窄脉冲电流源加工精密复杂型腔、型面的新工艺及新电源已投入模具、叶片的试生产中，显示出良好的技术经济效果，成形精度可达0．05mm；近期国外又发展了数百兆赫、数百纳秒级微小电流加工数十微米级零件的微细加工技术，开拓了电解加工用于微细加工的新领域，显示了脉冲电解加工巨大的发展潜势。试验研究表明，随着频率的提高、脉宽的变窄，引起阳极集中蚀除能力进一步加强，加工间隙进一步缩小，最终导致加工精度相应提高。所研制的1000A、20kHz矩形波电流源的脉冲前沿上升时间迭微秒级，快速短路保护时间仅为数十微秒级。     

离心压缩机闭式叶轮电解加工方法的研究

以离心式压缩机闭式叶轮为例,采用电解加工方法加工整体叶轮.介绍了电解加工闭式叶轮的思想,电解加工系统设计,阴极(刀具)的设计及制作方法.并结合实际加工工艺,对电解加工所造成的误差进行了说明,给电解加工在工业上的应用打下了更坚实的基础.     

Surface characteristics of ECMed titanium work samples for biomedical applications

Electrochemical machining (ECM) process has great potential on account of the versatility of its applications. ECM is being widely used in the manufacturing industry because hard metals can be machined regardless of the mechanical property of a work piece. Titanium is broadly used in a number of fields such as aerospace, power generation, automotive, chemical including petrochemical, and sporting goods. Apart from these applications, it has tremendous prospective in dental, medical industries, and biomedical engineering. The biological performance of titanium implant depends on their surface topography and form accuracy that includes various surface parameters. ECM is one of the alternative machining processes that can be applied to the machining of titanium implant for biomedical applications. The aim of this paper is to present experimental result of surface characteristics obtained on titanium samples, utilizing developed cross-flow electrolyte supply system in electrochemical machining. It is observed that electrolyte flow velocity and voltage between electrodes are some of the influencing parameters, which affect the surface characteristics. Titanium oxide layer has been generated on the machined surface, which facilitates the improvement of the corrosion and chemical resistance of titanium implant. Effects of electrolyte flow velocity and voltage during electrochemical machining process for generation of various surface characteristics have been successfully studied through experimentation. In the present work, the obtained surface roughness values on the titanium sample machined by ECM were in the range of 2.4 to 2.93???m, which is within acceptable value for the implants. Effects of electrolyte flow velocity and voltage on the material removal rate and machining accuracy in the form of overcut are also presented in the paper.     

高频脉冲电解加工电源的研制

近些年研究发现脉冲电流电解加工比起直流电解加工有更高的加工精度,为此研制了一套以IGBT(绝缘栅双极型晶体管)作为斩波元件的全桥逆变高频脉冲电解加工电源。详述了电源的总体结构、全桥逆变电路、以SG3525A为PWM(脉冲宽度调制)控制芯片的脉冲信号发生电路及调节电路和IGBT驱动电路的原理和过程。提出了一种使用大容量IGBT作为泄流元件的快速短路保护系统。该电源可输出占空比可调,频率达40kHz,最大为2kA的脉冲电流,输出波形稳定、不失真。     

高频群脉冲电化学微小型加工中的反向电流与压力波

针对脉冲电化学加工，建立了反向电流和压力波的数学模型，提出了高频群脉冲电化学加工方法。结果表明，充分发挥反向电流作用的电源频率在10～24kHz之间，压力波频率在400～1333Hz之间。反向电流仅与电极本身有关，它决定了高频群脉冲电化学加工的主脉冲频率；压力波则除了电极外，还与电解质性质和流速、极间间隙和电压等有关，它决定了高频群脉冲电化学加工的调制脉冲频率。根据模拟结果设计的实验表明，良好的加工质量来源于高频群脉冲带来的较小极间间隙。     

Electrochemical machining of the spiral internal turbulator

Electrochemical machining (ECM) is promising to machine the complex surface due to the advantages of no tool wear, stress free, and good machining accuracy. In this study, a machining method of the spiral internal ribs by ECM is presented. Firstly, the ECM experimental system is developed, which consists of electrolyte supply module, power supply unit, and workpiece-holding device. Then, a shaped cathode was used to process the spiral-turbulated hole on the built system. The shaped cathode was prepared by means of ultraviolet-curing mask method considering the expected spiral turbulator’s shape. Furthermore, parameters affecting the machining accuracy in shape duplication and machining efficiency are analyzed and discussed, especially the voltage and electrolyte concentration which have the main effect on the processed results.     

Discussion of ultrashort voltage pulses electrochemical micromachining: a review

One of the most effective way of electrochemical machining (ECM) accuracy increase is to carry out process with application of voltage pulses. In one of the variants of ECM, ultra short (nono- or picosecond range) voltage pulses are applied. It gives possibility to achieve high localization of electrochemical dissolution process and allows to machine microparts with accuracy less than 0.01 mm. However, because of the process principles, this variant of ECM has number of limitations which stop its wider application in micromanufacturing industry. Based on the literature review, the physical principles of ultrashort voltage pulses electrochemical machining were presented and anodic dissolution localization issues were discussed. Also, differences between other electrochemical machining variants were underlined. It gave possibility to identify limitations and future perspectives of industrial applications.     

IGBT半桥逆变式电火花加工脉冲电源

提出了逆变式电火花加工脉冲电源的工作原理,选用了半桥主回路结构和ＩＧＢＴ功率开关器件研制新型脉冲电源,总结了新型脉冲电源中高频变压器工作磁通密度、输出回路滤波电感和ＲＣ吸收网络的设计方法。工艺实验表明,新型脉冲电源在满足电火花粗、中加工性能要求的同时,将电能利用率由低于２５％提高到８０％以上,体积降低到原来的十分之一。     

脉冲电化学光整加工电源的设计

根据脉冲电化学光整加工PECM工艺需要大功率、窄脉宽、高频率电源的这一特殊要求,以绝缘栅极双极晶体管IGBT为主控元件设计了一种高频脉冲加工电源.重点介绍了其主电路以及IGBT的驱动保护电路的设计方法.实验结果表明,这种高频脉冲电源在高频、窄脉宽、大功率等方面均能满足该工艺的要求.