Drilling of Difficult-to-Cut Steel by Electrochemical Discharge Machining

In the case of workpieces made of difficult-to-cut materials, the small-diameter holes (1 mm diameter below) can be obtained by means of various nonconventional machining methods, one of these being the hybrid electrochemical discharge machining (ECDM). In the literature they researched, the authors could not find enough information that would allow them to establish adequate work conditions for the ECDM of small diameter holes by using an electrolyte. The use of a spring in order to obtain the work motion required to drill thin workpieces, and the need to remove the insulating film appearing on the workpiece, including in the last stage of the machining, were considered. The experimental research ended in the development of a power type function, which emphasizes the influence of the electrode tool diameter, of the voltage applied to the electrodes, of the capacity of the electric circuit involved in obtaining the electrical discharges, and of the density of the electrolyte upon the absolute axial wear of the electrode tool.