AN EXPERIMENTAL INVESTIGATION OF MACHINING PARAMETERS O N ELCTRICAL DISCHARGE MACHINING OF M - 250 (MARAGING) STEELS

Maraging steel (M 250) exhibits high level of strength and hardness and possesses an extreme resistance to crack propagation, even in the most extreme environments. Optimization of present work is essential for effective machining. The present work is aime d at characterizing the electric discharge machining of maraging steels on EDM. 27 experiments are conducted by varying EDM parameters such as current, pulse - on - time, and duty factor. The performance measures like Material removal rate, surface roughness, and hardness are assessed. It is concluded that metal removal rate, and surface roughness increases with increase in current, duty factor. But, as the pulse - on - time increases MRR and surface roughness decreases. Hardness value increases as the current valu e increases from 5A to 10A amps and then decreases as the current increases from 10A to 15A. The same effect is observed as in case of duty factor and pulse on - time. Average crack length and recast layer thickness increases with increase in current and dut y factor. But, there will be decreasing trend in case of pulse - on - time.