The Effects of Cutting Parameters on the Kerf and Surface Roughness on the Electrode in Electro Erosion Process

Abstract

During the electro erosion process, which is a thermal chip removal method, heating, melting and evaporation occur between the electrode material and the workpiece due to sparking and thermal effects, in this case both the workpiece and the electrode material are worn. In this study, the kerf angle and the electrode wear rate were analyzed by taking into account the size changes in the erosion areas of the copper electrode, which were eroded as a result of different processing parameters. a) b) Figure A. Kerf Angle Calculation (a) Longitudinal kerf measurement, b) Transverse kerf measurement)Purpose: In this study, electrode wear caused by machining from cold work tool steel with heat treated 60-62 HRC hardness was investigated by using electro erosion method and Cupro MAX CuCrZr electrode.In addition, it is aimed to determine the effects of processing parameters on the surface roughness of each electrode and electrode wear rates by going beyond the usual measurements.Theory and Methods: In this study,erosion process was performed using three different current values (6.25, 12.5, 25 A), three different pulse on times (3, 6, 9 µs) and pulse off times (4, 6, 8 µs), respectively, and the electrode wear rate of these processing parameters, the effects on kerf angle and surface roughness were analyzed by macro and analytical measurements.Surface roughness, kerf measurements and macro images of the electrodes were analyzed using Mitutoyo SJ200surface roughness tester, 0.001 mm precision mitutoyo micrometer and Nikon SMZ 745T microscope, respectively. ResultsThe results have shown that with increasing current, machining time decreased due to increased sparking between workpiece and electrode, but the average surface roughness, kerf angle and wear rate of the electrode increased.Theanalytical measurements and experimental results are presented and compared in Section 3. Conclusion:According to the analytical calculations and macro analysis results obtained as a result of experimental studies, it has been determined that as the pulse on time increases, the electrode wear rate decreases. The reduction in electrode wear resulted from the increase in the strength of the electrode due to the protective layer formed by the adhesion of the dielectric fluid and carbon particles released from the workpiece to the electrode surface. Highlights• Copper erosion.• EDM process.• Kerf measurement.