Investigation of concurrent tool rotation with ultrasonic vibration on dimensional accuracy in ECDM

A systematic investigation elucidates the impact of process variables (voltage, pulse on time, tool vibration amplitude, and tool rotation) on responses, namely, hole deviation (HD), entrance hole overcut (EHOC), and depth of penetration (DOP) during micro-drilling of glass using ultrasonic vibration-assisted rotary tool electrochemical discharge machining (UA-RT-ECDM). The experimental study employed a face-centered central composite design. Voltage has negligible influence on hole deviation and depth of penetration, with only a minor effect on entrance hole overcut. Pulse on time is insignificant for hole deviation and entrance hole overcut. A linear model fits hole deviation and entrance hole overcut. For HD, tool rotation and vibration amplitude contribute 72.86% and 20.2%, respectively. Tool rotation is the leading cause of EHOC, contributing 83.66%. A quadratic model describes DOP, which also includes the interaction effect between vibration amplitude and rotation speed. All developed models demonstrate strong agreement with the experimental data within the considered range.