Electric discharge machining also is known as spark erosion. It is the process of material removal based on the principle of metals by an interrupted electric spark discharge between the electrode tool and workpiece. Let us have a deep insight into the pros and cons that this process provided.
Advantages of EDM :
- It can be applied to all electrically conducting metals.
- Any complicated shape that can be machined.
- Machining time is less than conventional machining processes.
- It can also be employed for the extremely hardened workpiece.
- No mechanical stress is present in this process because of no contact between the tool and the workpiece.
- No burrs.
- Tolerances range +/- 0.005 can be achieved.
- Good surface finish can be attained.
- Creating small holes is not easily achieved by any other process other than EDM.
- Fragile and slender workplaces can be machined without distortion.
- The heat treatment process can be eliminated.
- Hard and corrosion-resistant surfaces, essentially needed for die making, can be developed by this process.
- Little or no polishing is required after the completion of the process.
Disadvantages of EDM :
- Machining time is too long.
- Excessive tool wear.
- High specific power consumption.
- Profile machining of complex contours is not possible.
- Only able to machine conductive materials.
- The metal removal rate is slow.
- Reproduction of sharp corners is the limitation of the process.
- Surface cracking may take place in some materials owing to their affinity to become brittle at room temperature.
- Especially when higher energy per pulse is used.