When working with metal, whether it’s cutting a tool or machining a final part, some features are too small to produce using traditional machining methods. For these applications, a process called electrical discharge machining (EDM) is used. EDM is also referred to as spark machining, spark eroding, burning, die sinking or wire erosion.

What is EDM?

Electrical discharge machining (EDM) is a metal working process in which controlled sparking is used to erode away a work piece. The EDM system consists of an electrode and the part (work piece). Material is removed from the work piece by a series of rapidly recurring current discharges between the two electrodes, separated by a dielectric liquid and subjected to an electric voltage. It is one of the most accurate manufacturing processes available for creating complex or simple shapes and geometries within parts and assemblies.

When is EDM used?

EDM is primarily used for hard metals or those that would be very difficult to machine with traditional techniques. EDM typically works with materials that are electrically conductive and can cut intricate contours or cavities in pre-hardened steel without the need for heat treatment to soften and re-harden them. This process is most widely used by the mold making tool and die industries, but is becoming a more common method of producing prototype and production parts where quantities are relatively low. EDM manufacturing is a very desirable manufacturing process when low counts or high accuracy is required.

Some of the advantages of EDM include machining of:

  • Complex shapes that would otherwise be difficult to produce with conventional cutting tools
  • Extremely hard material to very close tolerances
  • Very small work pieces where conventional cutting tools may damage the part from excess cutting tool pressure
  • Delicate sections and weak materials – can be machined without any distortion since there is no direct contact between tool and work piece

Some of the disadvantages of EDM include:

  • The slow rate of material removal
  • The additional time and cost used for creating electrodes for ram/sinker EDM
  • Reproducing sharp corners on the work piece is difficult due to electrode wear
  • Specific power consumption is very high

Have questions about EDM and how it can help you?  Call your Sales Manager at 770-901-3200 to discuss your project today!