Minimum roughness value in PMEDM with low-frequency vibration applied to workpiece

In powder-mixed electrical discharge machining (PMEDM), the application of low-frequency vibrations to a workpiece is considered beneficial to the machining quality. This study evaluates the average surface roughness (Ra) of SKD61 steel workpieces subjected to low-frequency vibrations during PMEDM using a Cu electrode and titanium powder. Specifically, Taguchi’s L25 experimental design method is used to evaluate the influence of the following process parameters: current, pulse-on time, concentration, push pressure, frequency, and amplitude. The analysis of variance technique is used to determine the minimum Ra (Ra${}_{min}$) value. The results show that Ra is most and least strongly influenced by $I$ and $A$, respectively. Further, Ra${}_{min}$ is found to be 1.03 $\mu$m.