Analysis of the Research Potential of Electrical Discharge Machining Process.

Electrical Discharge Machining (EDM) is a non-traditional machining process based on electro-thermal principles, where electrical energy is used to generate electrical spark. In this process, material removal mainly occurs due to thermal energy of the spark. The important challenges in electrical discharge machining process are low material removal rate (MRR), higher tool wear rate (TWR), lower finish of EDMed surfaces and high cost of dielectric fluid. It is evident that the overall efficiency of EDM process is quite low. There are newer technologies developed to overcome the limitations of the EDM process. It is known that most metals can burn in oxygen under normal conditions. Therefore, exploring this aspect leads to introduction of a new high-efficiency process known as EDM-induced ablation machining (EDM-AM) using multi-function electrode technology. Another emerging technology is dry electrical discharge machining. It is a technology that has the potential to replace conventional liquid based EDM, owing to its low tool electrode wear, thin recast layer, and eco-friendliness. Another process is EDM on cryogenically cooled workpiece, which brings out a balance between removal and finish of surfaces. The results of experimentation show an increase in the MRR of the cryogenically cooled workpiece technique, along with a decrease in the surface roughness value (Ra). Therefore, the advanced techniques investigated in this paper indicate newer methods to improve the material removal rate, at the same time surface roughness and overall process efficiency.