Prediction of electrode loss in micro-EDM drilling based on discharge time

The loss of electrodes in micro-electrical discharge machining (micro-EDM) is inevitable so that the electrode shape is deformed during processing, which seriously affects the final machining accuracy. Therefore, electrode loss prediction and compensation measures must be taken. In this paper, combined with the characteristics of the micro-electrical discharge machining computer numerical control (CNC) machine independently developed by the research group, a method to directly obtain the tool loss length and machined hole depth is put forward by integrating the electric contact method and coordinate transformation. Under the different processing conditions, the trends of electrode loss length with machining hole depth, the trends of electrode loss length with discharge time, and the trends of machining hole depth with discharge time were obtained. Meanwhile, the change rule was discussed and analyzed. Under fixed processing conditions, the hole depth is linearly related to the electrode loss length. The relationship between electrode loss length and hole depth and discharge time is approximately linear. Finally, the validity of the electrode loss prediction model is verified by the micro-EDM through-hole experiment.