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.
There is no direct contact between tool and work piece. Therefore, delicate sections and weak materials can be machined without perceivable distortion.
A good surface finish can be obtained; a very good surface may be obtained by redundant finishing paths.
Very fine holes can be attained.
Tapered holes may be produced.
Pipe or container internal contours and internal corners down to R .001".
Disadvantages of EDM include:
Difficulty finding expert machinists.
The slow rate of material removal.
Potential fire hazard associated with use of combustible oil based dielectrics.
The additional time and cost used for creating electrodes for ram/sinker EDM.
Reproducing sharp corners on the workpiece is difficult due to electrode wear.
Specific power consumption is very high.
Power consumption is high.
"Overcut" is formed.
Excessive tool wear occurs during machining.
Electrically non-conductive materials can be machined only with specific set-up of the process.