Electrodischarge machining (EDM) is a non-conventional manufacturing process, which is being used extensively in tool and die industries. In order to improve the performance of EDM process, it is essential to understand the mechanism of formation of cracks, and their size and distribution for each material machined at different machining conditions. Tungsten carbide cermet is an extensively used material for the manufacturing of dies for different applications in industries. An experimental study was conducted to see the formation of cracks and their morphology on electrodischarge machined tungsten carbide cermet under high current load. The copper tungsten electrode has been used for the study. Current and pulse duration have been selected as variable parameters. The objective of this investigation is to study the phenomenon of formation of microcracks at different energy input levels. It was observed that minimum cracks can be observed at low pulse energy per unit surface area. The detail of this study has been presented in the paper.
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