Electrochemical Discharge Machining under Thrust Force Control in Lathe-type Machine

Abstract

This paper deals with a lathe-type machine for electrochemical discharge machining (ECDM) and its machining performance under controlling the thrust force of a tool electrode onto a workpiece with an active tool electrode holder. In ECDM, the tool electrode has been generally pressed onto the workpiece at a small force by the gravity. In order to enhance the removal rate and compensate for the effect of the electrode weight, the electrode was suspended with coil springs and moved by electromagnetic attractive force generated with a solenoid. The applied voltage was calculated by calibration based on the reference thrust force and measured electrode displacement. This device was used on the lathe-type machine for straight turning. The tool electrode, workpiece and working fluid were tungsten, silica glass and NaCl solution, respectively. A one -way motion of the tool electrode allowed a straight contour of the workpiece periphery.