The effects of electro-discharge machining block electrode method for microelectrode machining

• Published in: Journal of micromechanics and microengineering 2002-09, Vol.12 (5), p.532-540, Article 304
• Main Authors: Ravi, Nachiappan, Chuan, Shan Xue
• Format: Article
• Language: English
• Subjects: Applied sciences; Electric discharge machining; Exact sciences and technology; Instruments, apparatus, components and techniques common to several branches of physics and astronomy; Mechanical engineering. Machine design; Mechanical instruments, equipment and techniques; Microelectrodes; Micromechanical devices and systems; Physics; Precision engineering; Precision engineering, watch making; Scanning electron microscopy; Wear of materials
• ISSN: 0960-1317; 1361-6439
• DOI: 10.1088/0960-1317/12/5/304

The electro-discharge machining block electrode method is a useful approach for producing microelectrodes due to its low investment cost and quick set-up. However, producing these microelectrodes (rods) to the desired size is a daunting task due to the occurrence of wear on the rod as well as on the cutting block. Hence, further research has been carried out to determine the differential wear between the two electrodes and to correlate the effects of the independent input parameters on the size of the average electrode diameter. The experimental results revealed that the sparking energy and electrode rotational speed influence only a slight variation in the size of the average microelectrode diameter. The electrode feeding length was found to be inversely linear to the size of the average microelectrode diameter at the reverse polarity condition. The SEM examination of microelectrodes machined at various feed lengths revealed that the size effect of the electrode imparts a vital role to the material removal characteristics. The application of several machining passes at different positions of the block is more efficient for producing precise microelectrodes. Finally, some application examples of the fabricated microelectrodes are included and the technological limitations of the block electrode method are discussed.