I. About electric discharge machining

"II. How to set machining conditions"

"III. How to design electrodes"

9. Electrode materials 

Copper, graphite, copper and tungsten are used for electrode materials.

The selection guide is as follows.


1) Copper

Copper (Standard JIS: more than 99.96% purity) is used.
As for the temper, H which is the hardest is suitable. H material has limit of the size of the material, and for large electrodes, material around 1/2H is used.

2) Graphite

Graphite fine particles are combined by combination materials called the binder. There are a number of products with the characteristics such as graphite particle size and binder materials. On the choice of materials, not only the performance of discharge machining, cutting efficiency at the time of electrode production is also important.

3) Copper tungsten

On making fine shape electrodes, it is characterized by good machinability.

In addition, the appropriateness of electrode materials should be judged with "the material of the workpiece," "contents of discharge machining" and "method of making the electrode" and so on.