Process Abrasive machining method in which a controlled spark discharges from an electrically charged electrodes creates a small hole in the workpiece.
Process Electrochemical process in which a grinding wheel of abrasive material rotates along with the surface that is covered with an electrolyte and in which both the electrolyte and the abrasive wheel contributes to the grinding.
Process Electrochemical process in which an electrolyte is pumped under pressure through the tool quickly corroding the surface of the workpiece to a cavity shaped like the tool.