Experimental investigation of single spark μ-EDM using electrodes fabricated with μ-turning process

Micro electrical discharge machining (μ-EDM) stands out as a widely employed non-traditional machining process with diverse applications in microfluidics, electronics, medical, aeronautics, and the automotive industry. This study is dedicated to the exploration of the single spark μ-EDM process utilizing a titanium tool electrode fabricated using a μm-turning process. Intriguingly, it is established that achieving a single spark necessitates a minimum tool diameter of 8 μm. Further, the effect of critical parameters such as voltage and capacitance on material removal rate (MRR), tool wear rate (TWR), as well as the shape and size of the resultant craters is investigated. A 7 μm tool electrode when subjected to a voltage of 100 V and a capacitance of 33 pF manifests a remarkably refined surface finish, demonstrating controlled erosion on the workpiece surface. The study also indicates that MRR and TWR vary exponentially with supplied discharge energy. This comprehensive analysis not only identifies optimal conditions for μm turning during tool fabrication but also elucidates the prerequisites for generating a controlled single spark during workpiece erosion. In essence, the findings presented here contribute valuable insights to the advancement of precision μ-EDM processes.