Synergistic roles of steady dwell tool feeding and ultrasonic vibrations in electrochemical discharge machining of alumina
Anurag Shanu, Ramver Singh, Pradeep Dixit
Abstract
A novel steady-dwell tool feeding approach is presented to create microfeatures in alumina substrate by ultrasonic-assisted electrochemical discharge machining (UA-ECDM). Comparisons among conventional ECDM, UA-ECDM, and UA-ECDM with steady-dwell feeding show distinct gas film formation. The impact of dwell time, step size, vibrational amplitude, and machining voltage on hole depth, overcut, and cross-sectional area removal rate (ARR) were assessed. Varying dwell time improved machining consistency,with material removal rates 1.8 to 2.3 times higher than continuous feeding. Ultrasonic assistance ensured uniform material removal beneath the tool, increasing ARR by 1.6 to 1.8 times. Combining steady-dwell tool feeding with ultrasonic assistance resulted in a 50% depth increase and a 33% ARR increase. The step size of 20 µm yielded the best results regarding depth, ARR, and smaller overcut. An ultrasonic vibration amplitude of 8 µm produced the maximum depth (365 µm) and ARR (20 × 10−3 mm3/min); additionally, higher voltage correlated with higher depth, overcut, and ARR.