In order to reduce the machining time and improve the surface quality of holes, a high speed self adjusting electrical discharge machining (EDM) approach is needed with independent flushing system that were able to remove the debris in the machining process. With the change in the gap distance and depth of the hole drilled, the electrode automatically adjusts the gap with the help of a linear actuator. For that, the optimum gap distance for getting maximum result is crucial. Taguchi L27 orthogonal array technique is used for the preliminary experimental analysis. The study revealed that discharge gap which is proportional to the gap voltage is the most influential parameter that affects the surface finish and material removal rate. The formation mechanism of the hole in the copper plate had found out, in order to get the optimum gap distance for the maximum MRR, TWR, and ROC. The results from the comparison experiment shows that the best result will be get at 0.5 mm gap distance and this can be taken as the optimum gap distance for the automatic feeding mechanism. In addition, low voltage and current would benefit for the EDM process working in micro level and for the removal of the recast layer.
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