Surface Integrity of Powder Mixed Electrical Discharge Treated Substrate at High Discharge Energies

The current study presents the investigation of powder mixed electrical discharge machining parameters in terms of surface integrity and machinability of β-type titanium alloy by utilizing three different dielectric medium. The three dielectric mediums, i.e., deionized water, multi-walled carbon nanotubes (MWCNTs) in deionized water and μHydroxyapatite powder (μHAp) in deionized water were employed for examination. To investigate the effectiveness of the powder mixed over the conventional electrical discharge process, the experiments were conducted according to the L18 experimental array, and metal removal rate (MRR) was studied. The results revealed that the machining in MWCNTs dielectric medium at 25 A current with negative polarity by incorporating copper/tungsten (Cu/W) electrode considered as optimal parameters of operation for higher material removal rate (MMR). MWCNTs dielectric medium significantly elevates the MRR to 58.7 mm3/min. However, in the conventional electrical discharge machining, the feasibility of the process for achieving the good surface integrity was constrained at high current. Moreover, the powder mixed electrical discharge machining shifts the efficiency of machining. The best surface integrity was recognized with PM-EDM even at the higher ranges of discharge energies. The presence of powder particles in the dielectric medium generates a uniform-patterned surface without any surface irregularities.