Electrical discharge machining

Metal fabrication process

Electrical discharge machining (EDM), also sometimes known as spark machining or spark eroding, is a metal cutting process whereby a desired shape is obtained by using electrical discharges (sparks). Material is removed from the work piece by a series of rapidly recurring current discharges between two electrodes, separated by a dielectric liquid and subject to an electric voltage. One of the electrodes is called the tool electrode (or simply the tool or electrode), while the other is called the workpiece electrode, or workpiece.

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