Multi-objective parameter optimization of ultrasonic vibration–assisted micro-EDM of Ti-6Al-4V alloys

Abstract

Regarding the low machining efficiency and poor surface quality in micro-electrical discharge machining (μ-EDM) of large depth-to-diameter ratio micro-holes, this paper focuses on ultrasonic vibration–assisted multi-objective optimization in μ-EDM to achieve high material removal rate (MRR) and low tool wear rate (TWR). In this work, second-order quadratic models were developed for MRR and TWR, considering the peak voltage (Up), peak current (Ip), pulse width (Width), frequency (Freq.), ultrasonic amplitude (UA), and rotation speed (Rot.) as the machining parameters, using the Plackett–Burman design and Box–Behnken design. The developed models were used for multi-objective optimization by desirability function approach to determine the optimum machining parameters. The optimized parameters were processed for micro-holes, and it was found that the surface quality of the micro-holes was significantly improved.