Experimental investigation into material removal mechanisms in High Speed Wire EDM

Abstract

High Speed Wire EDM (HSWEDM) is characterized by high relative velocities between its electrodes which appear in almost no other field of electrical discharge machining (EDM). Also, it previously has been described as a hybrid process. Consequently, material removal mechanisms show significant differences compared with other EDM processes. In this research, single discharge craters of HSWEDM processes were examined, and their geometrical features were associated with the underlying parameters. Discharge crater geometries on the workpiece electrode (anode) could be investigated by measurements whilst those on the wire electrode (cathode) were calculated. Results show that the high wire velocity leads to moving foot points on both electrodes. Pulse duration and the type of working medium influence the generation of discharge craters and thus their geometry and the modes of material removal. Static discharges and anodic dissolution could also be identified as material removal mechanisms and characterized in their geometrical properties. However, they are of secondary importance.

Recent Trends and Developments in the Electrical Discharge Machining Industry: A Review

“…Moreover, the parameters and factors of the technological process can impact not only the final result but also the material removal mechanism. In high-speed WEDM, for instance, anodic dissolution may be observed as a material removal mechanism [101]. In ceramic composites, depending on the strength of the discharge, it is possible to observe the breakage or fracture of reinforcing fibers and brittle fracture of the matrix [102].…”