Experimental investigation on low-frequency vibration-assisted µ-ED milling of Inconel 718

The microelectric discharge (µ-ED) milling is a competent process for the fabrication of complex 3-D shapes, but longer machining time limits the wide applications of the process. Therefore, in this work, a novel approach of low-frequency workpiece vibration-assisted µ-ED milling has used intending to improve the process performance. The experimental investigation has been performed using Taguchi L-16 orthogonal array to examine the effects of low-frequency workpiece vibration assistance in the µ-ED milling while fabricating microchannels on Inconel 718. The gap voltage, capacitance, and vibration frequency were selected as input parameters while material removal rate (MRR) and frontal electrode wear (FEW) were chosen as response variables. It has been observed that the MRR increases and FEW decreases with an increase in vibrational frequency up to an optimal value and then decreases for further increase in vibration frequency. The results disclose a positive influence of the low-frequency workpiece vibration of both MRR and FEW during µ-ED milling of Inconel 718. Finally, the effects of vibration and discharge energy on surface quality of fabricated microchannels were analyzed using field emission scanning electron microscopic images.