Experimental investigations to evaluate the effect of magnetic field on the performance of air and argon gas assisted EDM processes

The present paper focuses on the machining characteristics of EDM using the combined assistance of magnetic field and liquid-cum-gaseous dielectric namely, Magnetic Field - Air-Assisted EDM (MF-AAEDM) and Magnetic Field - Argon Gas Assisted EDM (MF-AGAEDM). The experimentation was carried out based on the central composite design to investigate the effect of peak current, pulse duration, duty cycle, magnetic flux density and air/gas pressure. The outcomes of two different processing condition have been compared to understand the effect of these parameters on material removal rate and electrode wear rate. The result shows the magnetic field increased both the material removal rate by 21-41% and electrode wear rate by 7-14% in EDM using liquid-air mixed dielectric. The exothermic reaction between air and work material increased the MRR by 10-18% in MF-AAEDM and the inert nature of argon gas reduced the EWR by 7-16% in MF-AGAEDM. The multi-objective optimization using genetic algorithm has also been performed in MF-AAEDM and MF-AGAEDM to obtain the optimum process parameters for maximum material removal rate and minimum electrode wear rate.