Discharge characteristics of cool electrode in EDM based on monopulse discharge

A monopulse discharge system was created to study the discharge characteristics of cool electrode under different temperatures. A model of the discharge channel was developed to analyze the influence of electrodes on the formation and expansion of the discharge channel and the maintaining voltage between the electrode and workpiece because of varying temperature. Under the same discharge conditions, the initial maintaining voltage of the hot electrode (22 V) was higher than that of the cool electrode (14 V). Pits on the surface of the hot electrode (about 610 μm) were larger than those of the cool electrode (about 425 μm). The diameters of the pits on the surface of the workpiece machined by the two electrodes were similar (about 820 and 830 μm). Cool electrode can compress the discharge channel and reduce electrode wear but only slightly influences the material removal rate.