Analysis of electrochemical machining process with ultrashort pulses considering stray inductance of pulse power supply

Machining characteristics of electrochemical machining with ultrashort pulses were investigated using numerical analysis considering the inductance of a power supply circuit. In a pulse power supply circuit of ECM, stray inductance occurs in the electric feeders. Because stray inductance influences the flow of the pulse current, the formation of the electric double layer is affected by the inductance. In order to investigate the influence of the inductance on the machining characteristics, numerical analysis was conducted considering the inductance of the power supply circuit. The electric field was analyzed by numerical simulation considering the electric double layer and faradaic current, and the circuit equation of the pulse power supply was solved considering stray inductance of the pulse power supply. Analytical results show that the inductance increases the rise time of electric current flowing through the machining gap when pulse voltage is applied. Therefore, longer pulse duration of pulse power supply is necessary to form the electric double layer when the inductance is larger. The voltage continues to be applied to the working gap even after the pulse voltage becomes low, limiting the effect of ultrashort voltage pulses due to inductance.