Fig. 2: The proposed current pulse analysis framework and sample current pulses for ECM and LECM for both samples (rolled and SLMed).

a In the proposed framework, the raw in-process current pulses were analysed to define current and pulse duration indicators. Thresholding approach was used to calculate the current indicators (pulse drop, avg. current, max. current value). Data count approach was used to calculate the pulse duration indicators (tON’, tRON, tOFF’). The indicators were used for pulse classification and subsequent statistical analysis. b The sample pulses show that passivation weakened with increasing voltage and LECM, as demonstrated by decreasing tRON and tOFF’ states. The current values of SLMed samples were lower than rolled samples, indicating a more corrosion-resistant microstructure.