Comparative Assessment of the Transient Temperature Response during Single Discharge Machining by Micro-EDM and LIP-MM Processes

Abstract

The micro-EDM is a well-established subtractive type of micro-manufacturing process and has been at the center of research for the last 15 years. The laser induced plasma micro-machining (LIP-MM) is a novel multimaterial and tool-less micro-machining process that also removes material through plasma. Since, both processes remove material through melting and vaporization, machining is always accompanied with heat affected zone. Since different materials have different thermo-physical properties, the plasma discharge energy level for minimal HAZ is material-dependent. The plasma discharge energy level corresponding to minimal HAZ can be experimentally determined by examining the dependence of the spatial distribution of the transient temperature response near the machined zone on the energy level. This paper, for the first time, presents an experimental investigation on real time measurement of the transient temperature response during single discharge machining at different pulse energy levels by the micro-EDM and the LIP-MM processes. The experimental data establishes a relationship between the pulse energy level and the transient temperature response and thus can be used for identifying the conditions for minimal HAZ in the two processes.