Abstract
This paper describes a simulation of workpiece geometry eroded by the die-sinking EDM. The geometry of workpiece is determined by the worn geometry of the tool electrode and the gap width distribution. The paper found that the local gap width is a function of the curvature and the inclination of the surface of the tool electrode from the feed direction, and that the local wear ratio of the tool electrode is affected by the local gap width. Moreover, the geometrical factors such as the curvature and the inclination are closely related to the local wear of the tool electrode. Starting with given contours of thin plate electrodes, the change of the workpiece geometry was simulated considering the tool wear and the gap width distribution. The erosion experiment was carried out by placing the tool and workpiece electrodes in a level position and feeding the tool electrode in a horizontal direction. Under these conditions, the debris concentration and the deposited carbon layer thickness, which influence the gap width and the anode wear, respectively, are thought to be uniform over the working surface. The simulation result coincided well with the measured geometry of the workpiece.
