Investigating the effect of process parameters on EDM performance of Inconel 725 alloy

In aerospace and automotive sectors, electrical discharge machining is essential for shaping hard-to-machine materials like Inconel 725. Using Taguchi's L16 orthogonal array, this study examines how electrode shape (round and square), peak current (8 and 12 A), pulse-on time (100 and 200 µs), and pulse-off time (1.2 and 1.6 µs) affect material removal rate and surface roughness. The study found that raising peak current from 8 to 12 A considerably improved material removal rate from 0.0593 to 0.1417 mm³/min. The maximum material removal rate was reached with a round electrode, 12 A current, 200 µs pulse-on, and 1.2 µs pulse-off duration. However, this setting resulted in the roughest surface finish (9.407 µm). However, the square electrode had better surface quality, with the lowest SR value of 5.965 µm at 8 A, 100 µs pulse-on, and 1.6 µs pulse-off. enhanced pulse-on time (200 µs), enhanced material removal rate by 47.77%, but shorter pulse-off time (1.2 µs) led to more efficient erosion owing to higher discharge frequency. The findings help precision machine advanced alloys like Inconel 725 by emphasizing the need for electrical discharge machining parameter selection to balance high material removal rate and surface integrity.