Electrical discharge machining (EDM) is a machining technology that uses the erosive power of electrical discharges. It can only be used on good conductors, primarily metals.

Over the years, PCM MECCANICA Srl has specialized in wire EDM. In this application, a taut conductive wire is used as an electrode to cut or profile the workpiece.

Machining Characteristics

The main characteristics of EDM machining are:

Ability to machine very hard metals (special steels, high-speed steels, hard metals, etc.) or metals hardened by heat or chemical treatments (tempered, carburized, etc.). Indeed, the hardness of the material being machined has a secondary influence on the removal rate or the energy required for machining.
Ability to machine the workpiece to create any geometric or volumetric shape. This is due to the fact that EDM does not require a rotating tool. It is possible to obtain sharp edges and create ribs and cavities with shapes or profiles impossible to achieve with other technologies. How it works

The machining process involves bringing a tool (the electrode) close to the material to be machined (the workpiece), all within an environment filled with a liquid dielectric. The electrode is charged with a positive polarity relative to the workpiece, as negatively charged material is more susceptible to erosion.

When the electrode and workpiece are sufficiently close, discharges are triggered between the two, eroding the workpiece in a manner complementary to the electrode's shape. As the workpiece is eroded, the electrode is advanced until the machining operation is complete. During machining, the electrode never comes into contact with the workpiece; this would create a short circuit instead of the sparks that cause erosion.