Modeling, Analysis, Evaluation, Selection and Experimental Investigation of EDM Process

Abstract

Electrical discharge machining (EDM) is one of the earliest non-traditional machining processes. EDM process is based on thermoelectric energy between the work piece and an electrode. A pulse discharge occurs in a small gap between the work piece and the electrode and removes the unwanted material from the parent metal through melting and vaporizing. The electrode and the work piece must have electrical conductivity in order to generate the spark. There are various types of products which can be produced using EDM such as dies and moulds. Parts of aerospace, automotive industry and surgical components can be finished by EDM. This study presents a methodology for evaluation, ranking and selection of parameters of Electric Discharge Machine by using MADM approach. A three stage selection procedure is used for identification of pertinent attributes and ranking is done with TOPSIS and graphical methods (Line graph and Spider Diagram. Then results of MADM approach are validated by comparing with results of experimental work done with ANOVA. This study also presents methodology for calculating the permanent function and numerical index of EDM system by dividing EDM into four subsystems and interactions between subsystems are represented into matrix form. This study provides a general formula which can be applied to any EDM system.