Advantages and Disadvantages of Electrical discharge machine (EDM)

The EDM process is most widely used by the mould-making tool and die industries, but is becoming a common method of making prototype and production parts, especially in the aerospace, automobile and electronics industries in which production quantities are relatively low.


Some of the advantages of EDM include machining of:

(a) Complex shapes that would otherwise be difficult to produce with conventional cutting tools.

(b) Extremely hard material to very close tolerances.

(c) Very small work pieces where conventional cutting tools may damage the part from excess cutting tool pressure.

(d) There is no direct contact between tool and work piece. Therefore delicate sections and weak materials can be machined without any distortion.

(e) A good surface finish can be obtained.

(f) Very fine holes can be easily drilled.

(g) Electrically non-conductive materials can be machined only with specific set-up of the process.


Some of the disadvantages of EDM include:

(a) The slow rate of material removal.

(b) The additional time and cost used for creating electrodes for ram/sinker EDM.

(c) Reproducing  sharp  corners  on  the  work  piece  is  difficult  due  to electrode wear.

(d) Specific power consumption is very high.

(e) Power consumption is high.

(f) "Over cut" is formed.

(g) Excessive tool wear occurs during machining.