30. Design and Development of Tool Electrode for Electrochemical Micromachining Using Reverse EMM Technique

The leaning of micro components is being utilized in various fields such as electronics, aerospace, automotive, biomedical, avionics, and optics industry. The surface finish of micro parts is enhanced by using electrochemical micro machining (EMM). Tool shape and size plays a major role in dimensional accuracy and shape of micro parts being produced. This paper presents design and fabrication of micro tool in reverse electrochemical micro machining with a usage of special fixture arrangement. Micro conical tools were fabricated by reverse polarity or reverse electrochemical micro machining aids to enhance material removal rate (MRR) and reduce overcut during machining processes. EMM is more favorable in the fabrication of a microelectrode due to no heat affected zone, lower machining time, absence of residual stress, and good surface quality. A hollow conical shaped micro tool of ɸ300 µm was fabricated from a hollow cylindrical shaped micro tool of Φ800 µm and the same hollow conical micro tool was used to machine the micro holes on 304 stainless steel of 400 µm thickness by EMM. The effect of electrolyte concentration with and without reciprocating feed was studied. The fabricated micro tools by reverse EMM is analyzed with output responses like MRR and overcut. It is inferred that hollow conical tool gives more MRR and produces lesser overcut.