Theoretical analysis of micro/nano electrochemical machining with ultra-short voltage pulses

The effect of pulse-on and pulse-offtimes on the efficiency of micro/nano ECM with ultra-short voltage pulses is theoretically analyzed. A new approximate analytical equation for the time of charging electrical double layer (EDL) is obtained. The equation takes into account all main parameters of the process. It enables one to determine the pulse-on time that provides a high localization of Faradaic process in the zones with small interelectrode gap and a high productivity of ECM process. The results of numerical calculations agree well with the data calculated by the proposed approximate analytical equation. The numerical calculations of the pulse-offtime are performed. The effect of reverse voltage pulse imposed in the pauses on the EDL relaxation time is analyzed. The amplitude of reverse voltage pulse is limited by the condition of the absence of the tool-electrode wear. The proposed algorithm for calculating the pulse-offtime and amplitude of reverse voltage pulse provides the required high coefficient of metal dissolution localization in the zone of small interelectrode gaps at a given pulse-on time. (C) 2020 Elsevier Ltd. All rights reserved.