ABSTRACT
Electric discharge machining (EDM) is presently considered a primary process as much as other conventional machining processes. Irrespective of hardness, it offers the ability to cut any electrically conductive material in the absence of cutting forces. This makes EDM the preferred choice in the manufacturing sector over other advanced machining technologies. In keeping with the progressive demand for miniaturized devices for technological applications, machining at small length scales has warranted increased attention of industrial R&D efforts. Consequently, different variants of the microscale version of EDM (micro-EDM, or µ-EDM) extend their application domains to all sectors that make use of micro-components or micro-features. Some of the potential application sectors in this regard are the biomedical, aerospace, automobile, microelectronics, jewelry, and precision equipment industries. The present chapter provides an introductory overview of micro-EDM technology and its variant processes. Tracing its history up to the present-day advancements, the chapter discusses the working principle of μ-EDM, and summarizes the crucial roles played by its principal machine components, and discusses their most important features. An overview of the varied forms of micro-EDM techniques are presented. The features 228and potential application domains of die-sinking micro-EDM and µ-EDM milling are briefly discussed. The working principle and machining behavior of micro-EDM drilling and other variants of micro-EDM are also addressed. The salient process parameters and their effects on the surface quality (SQ) of the machined faces are discussed with respect to the multi-physics nature of the length and time scales involved, as well as the geometric error and surface features. In addition, the chapter outlines the modeling techniques for the micro-EDM and the methodologies for theoretical estimation of temperature, crater-size distribution, etc. An exhaustive list of published works is included as References for an in-depth study of this novel art of machining.
